Selected GEOBASE "Amazon" Results

Record 1 of 40 in GEOBASE 2001/12-2002/08

TI: TRMM observations of intraseasonal variability in convective regimes over the Amazon .
AU: Petersen-W.A.; Nesbitt-S.W.; Blakeslee-R.J.; Cifelli-R.; Hein-P.; Rutledge-S.A.
AD: Dr. W.A. Petersen, Dept. of Atmospheric Science, Colorado State University, Fort Collins, CO 80523-1371, United States
EML: walt@radarmet.atmos.colostate.edu
SO: Journal-of-Climate. 2002 JUN 01; 15(11): 1278-1294
PY: 2002
LA: English
LS: English
AB: This study utilizes the Tropical Rainfall Measuring Mission (TRMM) satellite precipitation radar (PR), lightning imaging sensor (LIS), and passive microwave imager (TMI) data together with ground-based lightning data to investigate the vertical structure, lightning, and rainfall characteristics of Amazonian and subtropical South American convection for three separate wet seasons. These characteristics are partitioned as a function of 850-mb zonal wind direction, motivated by observations collected during the 6-week TRMM-Large-scale Biosphere-Atmosphere Experiment in Amazonia (LBA) field campaign. The TRMM-LBA field campaign observations suggest that systematic variations in Amazonian convective vertical structure, lightning, and rainfall are all linked to bimodal variations in the low-level zonal wind (e.g., easterly and westerly regimes). The more spatially and temporally comprehensive TRMM dataset used in this study extends the TRMM-LBA observations by examining regime variability in Amazonian and South American convective structure over a continental-scale domain. On a continental scale, patterns of east and west regime 850-700-mb winds combined with LIS lightning flash densities suggest the presence of synoptic-scale controls [e.g., intrusion of extratropical frontal systems and interaction with the South Atlantic Convergence Zone (SACZ) on regional-scale variability in convective vertical structure. TRMM PR, TMI, and ground-based lightning data suggest that regional variability in wetseason convective structure is most evident over the southern Amazon, Mato Grosso, Altiplano, southern Brazil, and eastern coastal regions of central and southern South America. Convective vertical structure, convective rainfall rates, and lightning activity are all more pronounced during easterly (westerly) regimes over the southern Amazon and Mato Grosso (Altiplano, and southern Brazil). Importantly, when considered with case study results from TRMM-LBA, the systematic differences in convective structure that occur as a function of regime suggest that associated regime differences may exist in the vertical distribution of diabetic heating. Hence the discrimination of convective vertical structure "regimes" over parts of the Amazon and vicinity based on a resolved variable such as the 850-700-mb zonal wind direction, while far from being perfect, may have important applications to the problems of cumulus parameterization, rainfall estimation, and retrievals of latent heating over the Amazon.
IS: 0894-8755
CP: United-States
DE: Convection-and-cloud-microphysics
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-METEOROLOGY-AND-CLIMATOLOGY (71-7-10)
KW: vertical-profile; rainfall; convection; lightning; remote-sensing
GE: South-America-Amazon
PT: Journal; Article
RF: 54
AN: 2423692
UD: 200207
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 2 of 40 in GEOBASE 2001/12-2002/08

TI: Hydrology of altered tropical forest .
AU: Giambelluca-T.W.
AD: T.W. Giambelluca, Department of Geography, University of Hawaii at Manoa, 2424 Maile Way, Honolulu, HI 96822, United States
EML: thomas@hawaii.edu
SO: Hydrological-Processes. 2002 JUN 15; 16(8): 1665-1669
PY: 2002
LA: English
LS: English
AB: The influences of land cover change on hydrologic processes, especially the effects of clearing forest, are a major environmental concern and the subject of much scientific research. In recognition of the rapid pace of deforestation in the Amazon and Southeast Asia, some of this work has been focused in the tropics in recent years. This research has tended to concentrate on the extremes: undisturbed forest versus recently cleared, actively utilized land. But, the landscape of tropical areas undergoing deforestation is not well represented by a two-class land-cover taxonomy. In the tropics, significant portions of cleared land revert quickly to secondary vegetation, which increasingly resembles forest with time. Remaining tropical forest, both remnant primary forest and forest regrowth, is being found in ever smaller patches. With primary tropical forest quickly disappearing, we may soon find that the only forest-like land cover in the tropics is composed of a patchwork of secondary vegetation and old forest, interspersed with more recently cleared patches. The hydrology of this 'altered forest' is not necessarily predictable from knowledge of the characteristics of original forest and cleared land only. How, then, does secondary vegetation differ from original forest and new clearings, and what are the effects of land cover fragmentation on the hydrologic cycle?
IS: 0885-6087
CP: United-Kingdom
DE: Plant-ecology:-communities; Land-use,-forestry-and-agriculture
SC: ECOLOGICAL-ABSTRACTS: TERRESTRIAL-ECOLOGY (73-4-6-6); GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-HYDROLOGY (71-6-13)
KW: tropical-forest; land-use-change; deforestation; succession; hydrological-change; old-growth-forest
GE: South-America-Amazonia
PT: Journal; Article
RF: 34
AN: 2422670
UD: 200207
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 3 of 40 in GEOBASE 2001/12-2002/08

TI: Diurnal variability of tropical rainfall retrieved from combined GOES and TRMM satellite information .
AU: Sorooshian-S.; Gao-X.; Hsu-K.; Maddox-R.A.; Hong-Y.; Gupta-H.V.; Imam-B.
AD: Dr. S. Sorooshian, Dept. of Hydrology and Water Rsrc., University of Arizona, P.O. Box 210011, Tucson, AZ 85721-0011, United States
EML: soroosh@hwr.arizona.edu
SO: Journal-of-Climate. 2002 MAY 01; 15(9): 983-1001
PY: 2002
LA: English
LS: English
AB: Recent progress in satellite remote-sensing techniques for precipitation estimation, along with more accurate tropical rainfall measurements from the Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI) and precipitation radar (PR) instruments, have made it possible to monitor tropical rainfall diurnal patterns and their intensities from satellite information. One year (August 1998-July 1999) of tropical rainfall estimates from the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks (PERSIANN) systems were used to produce monthly means of rainfall diurnal cycles at hourly and 1< degrees > x 1< degrees > scales over a domain (30< degrees >S-30< degrees >N, 80< degrees >E-10< degrees >W) from the Americas across the Pacific Ocean to Australia and eastern Asia. The results demonstrate pronounced diurnal variability of tropical rainfall intensity at synoptic and regional scales. Seasonal signals of diurnal rainfall are presented over the large domain of the tropical Pacific Ocean, especially over the ITCZ and South Pacific convergence zone (SPCZ) and neighboring continents. The regional patterns of tropical rainfall diurnal cycles are specified in the Amazon, Mexico, the Caribbean Sea, Calcutta, Bay of Bengal, Malaysia, and northern Australia. Limited validations for the results include comparisons of 1) the PERSIANN-derived diurnal cycle of rainfall at Rondonia, Brazil, with that derived from the Tropical Ocean Global Atmosphere Coupled Ocean-Atmosphere Response Experiment (TOGA COARE) radar data; 2) the PERSIANN diurnal cycle of rainfall over the western Pacific Ocean with that derived from the data of the optical rain gauges mounted on the TOGA-moored buoys: and 3) the monthly accumulations of rainfall samples from the orbital TMI and PR surface rainfall with the accumulations of concurrent PERSIANN estimates. These comparisons indicate that the PERSIANN-derived diurnal patterns at the selected resolutions produce estimates that are similar in magnitude and phase.
IS: 0894-8755
CP: United-States
DE: Precipitation-assessment
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-HYDROLOGY (71-6-1)
KW: diurnal-variation; tropical-meteorology; precipitation-assessment; remote-sensing; precipitation-intensity
GE: Pacific-Ocean; Australia-North; Asia-East; Malaysia; Bay-of-Bengal; Mexico; Caribbean-Sea; South-America-Amazon; Brazil-Rondonia-State
PT: Journal; Article
RF: 37
AN: 2418374
UD: 200207
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 4 of 40 in GEOBASE 2001/12-2002/08

TI: Nitrogen controls on climate model evapotranspiration .
AU: Dickinson-R.E.; Berry-J.S.; Bonan-G.B.; Collatz-G.J.; Field-C.B.; Fung-I.Y.; Goulden-M.; Hoffmann-W.A.; Jackson-R.B.; Myneni-R.; Sellers-P.J.; Shaikh-M.
AD: R.E. Dickinson, School of Earth/Atmospheric Sciences, Georgia Institute of Technology, 221 Bobby Dodd Way, Atlanta, GA 30332-0340, United States
EML: robted@eas.gatech.edu
SO: Journal-of-Climate. 2002 JAN 01; 15(1): 278-295
PY: 2002
LA: English
LS: English
AB: Most evapotranspiration over land occurs through vegetation. The fraction of net radiation balanced by evapotranspiration depends on stomatal controls. Stomates transpire water for the leaf to assimilate carbon, depending on the canopy carbon demand, and on root uptake, if it is limiting. Canopy carbon demand in turn depends on the balancing between visible photon-driven and enzyme-driven steps in the leaf carbon physiology. The enzyme-driven component is here represented by a Rubisco-related nitrogen reservoir that interacts with plant-soil nitrogen cycling and other components of a climate model. Previous canopy carbon models included in GCMs have assumed either fixed leaf nitrogen, that is, prescribed photosynthetic capacities, or an optimization between leaf nitrogen and light levels so that in either case stomatal conductance varied only with light levels and temperature. A nitrogen model is coupled to a previously derived but here modified carbon model and includes, besides the enzyme reservoir, additional plant stores for leaf structure and roots. It also includes organic and mineral reservoirs in the soil; the latter are generated, exchanged, and lost by biological fixation, deposition and fertilization, mineralization, nitrification, root uptake, denitrification, and leaching. The root nutrient uptake model is a novel and simple, but rigorous, treatment of soil transport and root physiological uptake. The other soil components are largely derived from previously published parameterizations and global budget constraints. The feasibility of applying the derived biogeochemical cycling model to climate model calculations of evapotranspiration is demonstrated through its incorporation in the Biosphere-Atmosphere Transfer Scheme land model and a 17-yr Atmospheric Model Inter comparison Project II integration with the NCAR CCM3 GCM. The derived global budgets show land net primary production (NPP), fine root carbon, and various aspects of the nitrogen cycling are reasonably consistent with past studies. Time series for monthly statistics averaged over model grid points for the Amazon evergreen forest and lower Colorado basin demonstrate the coupled interannual variability of modeled precipitation, evapotranspiration. NPP, and canopy Rubisco enzymes.
IS: 0894-8755
CP: United-States
DE: Boundary-layer-meteorology
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-METEOROLOGY-AND-CLIMATOLOGY (71-7-7)
KW: evapotranspiration; nitrogen-cycle; canopy-exchange; climate-modeling
PT: Journal; Article
RF: 59
AN: 2417001
UD: 200207
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 5 of 40 in GEOBASE 2001/12-2002/08

TI: Regional controls on geomorphology, hydrology, and ecosystem integrity in the Orinoco Delta, Venezuela .
AU: Warne-A.G.; Meade-R.H.; White-W.A.; Guevara-E.H.; Gibeaut-J.; Smyth-R.C.; Aslan-A.; Tremblay-T.
AD: A.G. Warne, US Geological Survey, 651 Federal Drive, Guaynabo, Puerto Rico
EML: agwarne@usgs.gov
SO: Geomorphology. 2002; 44(3-4): 273-307
PY: 2002
LA: English
LS: English
AB: Interacting river discharge, tidal oscillation, and tropical rainfall across the 22,000 km2 Orinoco delta plain support diverse fresh and brackish water ecosystems. To develop environmental baseline information for this largely unpopulated region, we evaluate major coastal plain, shallow marine, and river systems of northeastern South America, which serves to identify principal sources and controls of water and sediment flow into, through, and out of the Orinoco Delta. The regional analysis includes a summary of the geology, hydrodynamics, sediment dynamics, and geomorphic characteristics of the Orinoco drainage basin, river, and delta system. Because the Amazon River is a major source of sediment deposited along the Orinoco coast, we summarize Amazon water and sediment input to the northeastern South American littoral zone. We investigate sediment dynamics and geomorphology of the Guiana coast, where marine processes and Holocene history are similar to the Orinoco coast. Major factors controlling Orinoco Delta water and sediment dynamics include the pronounced annual flood discharge; the uneven distribution of water and sediment discharge across the delta plain; discharge of large volumes of water with low sediment concentrations through the Rio Grande and Araguao distributaries; water and sediment dynamics associated with the Guayana littoral current along the northeastern South American coast; inflow of large volumes of Amazon sediment to the Orinoco coast; development of a fresh water plume seaward of Boca Grande; disruption of the Guayana Current by Trinidad, Boca de Serpientes, and Gulf of Paria; and the constriction at Boca de Serpientes. < copyright > 2002 Elsevier Science B.V. All rights reserved.
IS: 0169-555X
CP: Netherlands
DE: Regional-physiography
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-LANDFORMS (71-2-6)
KW: regional-geography; geomorphology; hydrology; aquatic-ecosystem
GE: Venezuela-Orinoco-Delta
PT: Journal; Article
RF: 94
AN: 2415918
UD: 200207
PI: S0169555X01001799
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 6 of 40 in GEOBASE 2001/12-2002/08

TI: Spatial and temporal analysis of a tidal floodplain landscape - Amapa, Brazil - Using geographic information systems and remote sensing.
AU: Pereira-V.F.G.; Congalton-R.G.; Zarin-D.J.
AD: V.F.G. Pereira, Department of Natural Resources, University of New Hampshire, Durham, NH 03824, United States
EML: russ.congalton@unh.edu
SO: Photogrammetric-Engineering-and-Remote-Sensing. 2002; 68(5): 463-472
PY: 2002
LA: English
LS: English
AB: For at least 12,000 years, Amazonian floodplains (varzea) have been exploited by human populations. Although they represent a small fraction of the Amazon basin, floodplains contain the most productive ecosystems of the region. Easy access and the abundance of valuable forest products have historically led to higher human population densities and higher resource use than in many interfluvial areas. Recent research has brought attention to land-use and land-cover change in upland Amazonian forests, but relatively little research has been conducted on similar dynamics in the floodplains. In this project, we used photointerpretation of 1970s aerial photographs and digital image classification of Landsat Thematic Mapper (TM) 5 imagery from the 1990s to produce land-cover maps used for change detection analysis. A study area in the tidal floodplains of the State of Amapa, in the northern Brazilian Amazon, was evaluated. The accuracy of the Landsat TM classification and errors inherent to the techniques used were assessed. Several changes in the study site were observed, including increases in the areal extent of secondary growth and palm forests and corresponding decreases in intact varzea forest area.
IS: 0099-1112
CP: United-States
DE: Applications:-biosphere
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-REMOTE-SENSING-GIS-AND-MAPPING (71-8-8-3)
KW: GIS; remote-sensing; floodplain; digital-image; aerial-photograph; Landsat-thematic-mapper; land-use-change
GE: Brazil-Amazon-Basin
PT: Journal; Review
RF: 39
AN: 2415213
UD: 200207
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 7 of 40 in GEOBASE 2001/12-2002/08

TI: The River Amazon at Obidos (Brazil): Statistical studies of the discharges and water balance.
OT: L'Amazone a Obidos (Bresil): Etude statistique des debits et bilan hydrologique.
AU: Callede-J.; Guyot-J.L.; Ronchail-J.; Molinier-M.; De-Oliveira-E.
AD: J. Callede, IRD, Brasilia CEP 71050-191, Brazil
EML: cld@apis.com.br
SO: Hydrological-Sciences-Journal. 2002; 47(2): 321-333
PY: 2002
LA: English; French
LS: English; French
AB: New discharge measurements carried out within the "Hidrologia e geoquimica na Bacia Amazonica" (HiBAm) Project at Obidos have improved the knowledge about the hydrological characteristics of the Amazon at this station, which controls the highest discharges in the world. A new correction method determines the daily discharge with an accuracy of ±3.0%. The reconstruction of the missing data, using observations from Manaus, makes it possible to build a chronology for almost one century. With this sample starting in 1902, the interannual average discharge of the Amazon at Obidos is 163 000 m3 s-1, with an extremely weak irregularity coefficient (K3 = 1.28). The decennial low water (78 000 m3 s-1) is similar to the centenary flood of the River Congo at Brazzaville. The decennial flood is estimated to be 260 000 m3 s-1. Water balance studies indicate an outflow deficit of 1193 mm, which can be identified with actual evapotranspiration. In conclusion, the Amazon is confirmed to be the most powerful and regular river of the planet.
IS: 0262-6667
CP: United-Kingdom
DE: Runoff,-streamflow-and-basins
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-HYDROLOGY (71-6-5)
KW: river-discharge; hydrological-regime; water-budget; statistical-analysis
GE: Brazil-Para-State-Obidos; Brazil-Amazon-River
PT: Journal; Article
RF: 19
AN: 2409847
UD: 200207
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 8 of 40 in GEOBASE 2001/12-2002/08

TI: The JERS-1 Amazon Multi-season Mapping Study (JAMMS): Science objectives and implications for future missions .
AU: Freeman-A.; Chapman-B.; Siqueira-P.
AD: A. Freeman, Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, United States
EML: tony.freeman@jpl.nasa.gov
SO: International-Journal-of-Remote-Sensing. 2002 APR 10; 23(7): 1447-1460
PY: 2002
LA: English
LS: English
AB: In late September 1995, the National Space Development Agency of Japan (NASDA) began a new phase of operations for the Japanese Earth Remote Sensing satellite (JERS-1) Synthetic Aperture Radar (SAR)-the Global Rain Forest Mapping (GRFM) project. The first rainforest area to be mapped was the Amazon basin, between September and November of that year (the low flood season for much of the region), in support of the JERS-1 Amazon Multi-season Study (JAMMS), sponsored by NASA. This data acquisition was repeated 6 months later to acquire a second map of the Amazon, during the high flood season in May/June of 1996. The main objective of the JAMMS project was to generate a map of inundation over the Amazon basin by comparing data from the high- and low-flood seasons. Most of the data collected during these two phases of the JAMMS project, a total of < similar-to > 5000 frames of data, was received and processed by the Alaska SAR Facility (ASF), then sent to the Jet Propulsion Laboratory (JPL) and NASDA for post-processing and analysis. The quality of the data processed by ASF for the JAMMS project has proved to be exceptional. This paper is a summary of the JAMMS project, which has resulted in a scientific dataset of very high value-a multi-season snapshot of one of the most difficult areas on Earth to monitor, even from space.
IS: 0143-1161
CP: United-Kingdom
DE: Applications:-biosphere
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-REMOTE-SENSING-GIS-AND-MAPPING (71-8-8-3)
KW: JERS-1; seasonal-variation; rainforest; synthetic-aperture-radar; flooding; vegetation-mapping
GE: Brazil-Amazonia
PT: Journal; Article
RF: 17
AN: 2408885
UD: 200207
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 9 of 40 in GEOBASE 2001/12-2002/08

TI: The JERS Amazon multi-season mapping study (JAMMS): Observation strategies and data characteristics .
AU: Chapman-B.; Siqueira-P.; Freeman-A.
AD: B. Chapman, Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109, United States
EML: bruce.chapman@jpl.nasa.gov
SO: International-Journal-of-Remote-Sensing. 2002 APR 10; 23(7): 1427-1446
PY: 2002
LA: English
LS: English
AB: The Japanese Earth Resources Satellite (JERS-1) Amazon Multi-season Mapping Study (JAMMS), part of the Global Rain Forest Mapping (GRFM) project led by the National Space Development Agency of Japan (NASDA), had an ambitious agenda to map the entire Amazon river floodplain (and surrounding areas) twice at high resolution. The observation strategy carried out by NASDA for the JAMMS project and the other elements of the GRFM project (1995-1997) constituted the first time that a spaceborne Synthetic Aperture Radar (SAR) successfully implemented a continental scale, coordinated seasonal mapping campaign. This observation strategy, chosen around the flooding cycle of the major river system, was designed to provide the first high-resolution measurement of inundation extent by the Amazon river and its tributaries. In order for the scientific community at large to be able to exploit this dataset, the characteristics of the data (resolution, radiometric and geometric calibration, coverage, and ability to be mosaicked) must be well understood. We find that the quantization of the Alaska SAR Facility (ASF) imagery impacts the range of backscatter values that may be observed, in contrast to the NASDA processed imagery. The noise equivalent < sigma >0 is - 15 dB at worst, but improves to about - 20 dB at the centre of the swath. The resolution of the ASF imagery is slightly worse than that processed by NASDA. The initial geolocation accuracy of the ASF processed imagery is quite poor, but may be improved during the mosaicking process. The relative radiometric calibration of the data may be improved to about 0.2 dB by comparing the calibration of overlapping imagery, and through a careful analysis of cross-track trends in the data.
IS: 0143-1161
CP: United-Kingdom
DE: Applications:-biosphere
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-REMOTE-SENSING-GIS-AND-MAPPING (71-8-8-3)
KW: JERS-1; floodplain; seasonal-variation; vegetation-mapping; flooding; synthetic-aperture-radar; rainforest
GE: Brazil-Amazonia
PT: Journal; Article
RF: 22
AN: 2408884
UD: 200207
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 10 of 40 in GEOBASE 2001/12-2002/08

TI: Spectral remote sensing reflectances of coastal waters in French Guiana under the Amazon influence .
AU: Froidefond-J.-M.; Gardel-L.; Guiral-D.; Parra-M.; Ternon-J.-F.
AD: J.-M. Froidefond, UMR EPOC no. 5805, CNRS, Universite Bordeaux-1, Avenue des Facultes, Talence Cedex 33405, France
EML: jm.froidefond@geocean.u-bordeaux.fr
SO: Remote-Sensing-of-Environment. 2002; 80(2): 225-232
PY: 2002
LA: English
LS: English
AB: The French Guiana coast, located about 500 km north of the Amazon mouth, is characterized by mangroves and large mud banks migrating northwestwards. These banks are composed of fine clay sediments originating from the Amazon Riven In November 1998, field work was carried out on the Mahury River to measure the water colour and the concentration of suspended particles in surface water. An increase of the remote sensing reflectance due to high concentration of mineral particles was observed. The Mahury River survey (November 1998), together with an oceanographic survey onboard the ANTEA vessel (PRECHICO cruise, April 1999), enabled us to identify several classes of remote sensing reflectance spectra characterizing the continental shelf between Cayenne and the Brazil frontier: (1) light blue waters above the shelf break; (2) low salinity dark brown waters above the continental shelf, originating from the Amazon River; (3) green waters above the 20-m isobath; and (4) beige waters close to the coast and in the rivers mouths. The normalized water leaving radiances (nLw) computed from these spectra in the spectral bands of SeaWiFS are examined. The standard OC2 performs poorly in retrieving chlorophyll from the reflectance data because of the relatively high suspended particulate matter concentrations. < copyright > 2002 Elsevier Science Inc. All rights reserved.
IS: 0034-4257
CP: United-States
DE: Remote-sensing:-numerical-and-image-analysis; Remote-sensing
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-REMOTE-SENSING-GIS-AND-MAPPING (71-8-5-4); OCEANOGRAPHIC-LITERATURE-REVIEW: MARINE TECHNOLOGY (76-14-3)
KW: remote-sensing; mangrove; coastal-zone; color; spectral-reflectance
GE: French-Guiana; Atlantic-Ocean
PT: Journal; Article
RF: 34
AN: 2414218
UD: 200207
PI: S0034425701003017
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 11 of 40 in GEOBASE 2001/12-2002/08

TI: Outgassing from Amazonian rivers and wetlands as a large tropical source of atmospheric CO<inf>2</inf> .
AU: Richey-J.E.; Melack-J.M.; Aufdenkampe-A.K.; Ballester-V.M.; Hess-L.L.
AD: J.E. Richey, School of Oceanography, University of Washington, Seattle, WA 98195, United States
EML: jrichey@u.washington.edu
SO: Nature. 2002 APR 11; 416(6881): 617-620
PY: 2002
LA: English
LS: English
AB: Terrestrial ecosystems in the humid tropics play a potentially important but presently ambiguous role in the global carbon cycle. Whereas global estimates of atmospheric CO<inf>2</inf> exchange indicate that the tropics are near equilibrium or are a source with respect to carbon, ground-based estimates indicate that the amount of carbon that is being absorbed by mature rainforests is similar to or greater than that being released by tropical deforestation (about 1.6 Gt Cyr-1). Estimates of the magnitude of carbon sequestration are uncertain, however, depending on whether they are derived from measurements of gas fluxes above forests or of biomass accumulation in vegetation and soils. It is also possible that methodological errors may over-estimate rates of carbon uptake or that other loss processes have yet to be identified. Here we demonstrate that outgassing (evasion) of CO<inf>2</inf> from rivers and wetlands of the central Amazon basin constitutes an important carbon loss process, equal to 1.2 ± 0.3 Mg C ha-1 yr-1. This carbon probably originates from organic matter transported from upland and flooded forests, which is then respired and outgassed downstream. Extrapolated across the entire basin, this flux - at 0.5 Gt C yr-1 - is an order of magnitude greater than fluvial export of organic carbon to the ocean. From these findings, we suggest that the overall carbon budget of rainforests, summed across terrestrial and aquatic environments, appears closer to being in balance than would be inferred from studies of uplands alone.
IS: 0028-0836
CP: United-Kingdom
DE: Biogeochemical-cycles
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-SYNOPTIC-GEOGRAPHY (71-1-3)
KW: degassing; river-water; wetland; tropical-forest; carbon-dioxide; biogeochemical-cycle
GE: South-America-Amazonia
PT: Journal; Article
RF: 30
AN: 2412931
UD: 200207
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 12 of 40 in GEOBASE 2001/12-2002/08

TI: Spatial and temporal variabilities of rainfall in tropical South America as derived from climate prediction Center merged analysis of precipitation .
AU: Matsuyama-H.; Marengo-J.A.; Obregon-G.O.; Nobre-C.A.
AD: H. Matsuyama, Department of Geography, Graduate School of Science, Tokyo Metropolitan University, 1-1, Minami-Ohsawa, Hachiouji-shi, Tokyo 192-0397, Japan
EML: matuyama@geog.metro-u.ac.jp
SO: International-Journal-of-Climatology. 2002; 22(2): 175-195
PY: 2002
LA: English
LS: English
AB: We investigated the spatial and temporal variabilities of Climate Prediction Center merged analysis of precipitation (CMAP) in tropical South America from 1979 to 1998. First, we validated CMAP using other hydrometeorological data. In comparison with the high-density precipitation data of the Global Historical Climatology Network (GHCN) Ver. 2, CMAP reproduces the spatial pattern well, although it underestimates (overestimates) heavy (light) precipitation. CMAP also reproduces the interannual variability well, compared with the discharge data of the River Amazon. Next, we applied the rotated empirical orthogonal function (REOF) to CMAP after subtracting the annual cycle. Simultaneous and lag correlations were calculated among the scores of REOFs 1 to 4, the southern oscillation index, and the dipole index of the Atlantic. REOF 1 (15%) represents the north-south pattern that exhibits the maximum precipitation in the summer hemisphere. REOF 2 (12%) indicates the gradual decrease of precipitation in the northern part of tropical South America, reflecting the effect of the Atlantic. REOF 3 (11%) exhibits an east-west pattern related to El Nino. In REOF 4 (7%), the centre of the factor loading is located in Colombia, and the score jumps abruptly around 1985-86. The Lepage test detected the abrupt increase of CMAP in 1985-86 around Colombia. Since such a jump is not found in GHCN Ver. 2, the discontinuous changes of CMAP and REOF 4 around 1985-86 are artificial and peculiar to CMAP. In this region, CMAP should be applied with caution when evaluating recent trends and the interannual variability. The importance of the abrupt increase of precipitation around Colombia is also addressed. Copyright < copyright > 2002 Royal Meteorological Society.
IS: 0899-8418
CP: United-Kingdom
DE: Weather-and-climate-forecasting
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-METEOROLOGY-AND-CLIMATOLOGY (71-7-12)
KW: spatiotemporal-analysis; precipitation-climatology-; prediction; water-budget; annual-variation
GE: South-America
PT: Journal; Article
RF: 53
AN: 2404633
UD: 200207
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 13 of 40 in GEOBASE 2001/12-2002/08

TI: Effects of penetrative radiation of the upper tropical ocean circulation .
AU: Murtugudde-R.; Beauchamp-J.; McClain-C.R.; Lewis-M.; Busalacchi-A.J.
AD: Dr. R. Murtugudde, ESSIC/CSS, University of Maryland, College Park, MD 20742, United States
EML: ragu@essic.umd.edu
SO: Journal-of-Climate. 2002 MAR 01; 15(5): 470-486
PY: 2002
LA: English
LS: English
AB: The effects of penetrative radiation on the upper tropical ocean circulation have been investigated with an ocean general circulation model (OGCM) with attenuation depths derived from remotely sensed ocean color data. The OGCM is a reduced gravity, primitive equation, sigma coordinate model coupled to an advective atmospheric mixed layer model. These simulations use a single exponential profile for radiation attenuations in the water column, which is quite accurate for OGCMs with fairly coarse vertical resolution. The control runs use an attenuation depth of 17 m while the simulations use spatially variable attenuation depths. When a variable depth oceanic mixed layer is explicitly represented with interactive surface heat fluxes, the results can be counterintuitive. In the eastern equatorial Pacific, a tropical ocean region with one of the strongest biological activity, the realistic attenuation depths result in increased loss of radiation to the subsurface, but result in increased sea surface temperatures (SSTs) compared to the control run. Enhanced subsurface heating leads to weaker stratification, deeper mixed layers, reduced surface divergence, and hence less upwelling and entrainment. Thus, some of the systematic deficiencies in the present-day climate models, such as the colder than observed cold tongue in the equatorial Pacific may simply be related to inaccurate representation of the penetrative radiation and can be improved by the formulation presented here. The differences in ecosystems in each of the tropical oceans are clearly manifested in the manner in which biological heat trapping affects the upper ocean. While the tropical Atlantic has many similarities to the Pacific, the Amazon, Congo, and Niger Rivers' discharges dominate the attenuation of radiation. In the Indian Ocean, elevated biological activity and heat trapping are away from the equator in the Arabian Sea and the southern Tropics. For climate models, in view of their sensitivity to the zonal distribution of SST, using a basin mean of the ocean color-derived attenuation depth reduces the SST errors significantly in the Pacific although they occur in regions of high mean SST and may have potential feedbacks in coupled climate models. On the other hand, the spatial variations of attenuation depths in the Atlantic are crucial since using the basin mean produces significant errors. Thus the simplest and the most economic formulation is to simply employ the annual mean spatially variable attenuation depths derived from ocean color.
IS: 0894-8755
CP: United-States
DE: Circulation; Air-sea-interaction
SC: OCEANOGRAPHIC-LITERATURE-REVIEW: PHYSICAL-OCEANOGRAPHY (76-1-5); GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-METEOROLOGY-AND-CLIMATOLOGY (71-7-8)
KW: oceanic-general-circulation-model; heat-flux; solar-radiation; upper-ocean
GE: Pacific-Ocean-Equatorial-East
PT: Journal; Article
RF: 49
AN: 2403331
UD: 200207
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 14 of 40 in GEOBASE 2001/12-2002/08

TI: Insolation, moisture balance and climate change on the South American Altiplano since the Last Glacial Maximum .
AU: Rowe-H.D.; Dunbar-R.B.; Mucciarone-D.A.; Seltzer-G.O.; Baker-P.A.; Fritz-S.
AD: H.D. Rowe, Geological and Envtl. Sciences, Bldg. 320, Stanford University, Stanford, CA 94305-2115, United States
EML: harry@pangea.stanford.edu
SO: Climatic-Change. 2002; 52(1-2): 175-199
PY: 2002
LA: English
LS: English
AB: Sediment cores from Lake Titicaca contain proxy records of past lake level and hydrologic change on the South American Altiplano. Large downcore shifts in the isotopic composition of organic carbon, C/N, wt. %Corg, %CaCO<inf>3</inf>, and % biogenic silica illustrate the dynamic changes in lake level that occurred during the past 20,000 years. The first cores taken from water depths greater than 50 meters in the northern subbasin of the lake are used to develop and extend the paleolake-level record back to the Last Glacial Maximum (LGM). Quantitative estimates of lake level are developed using transfer functions based on the < delta >13C of modern lacustrine organic sources and the < delta >13C of modern sedimented organic matter from core-tops. Lake level was slightly higher than modern during much of the post-LGM (20,000-13,500 yr BP) and lake water was fresh under the associated outflow conditions. The Pleistocene/Holocene transition (13,500-7,500 yr BP) was a period of gradual regression, punctuated by minor trangressions. Following a brief highstand at about 7250 yr BP, lake level dropped rapidly to 85 m below the modern level, reaching maximum lowstand conditions by 6250 yr BP. Lake level increased rapidly between 5000 yr BP and 4000 yr BP, and less rapidly between 4000 yr BP and 1500 yr BP. Lake level remained relatively high throughout the latest Holocene with only minor fluctuations (< 12 meters). Orbitally induced changes in solar insolation, coupled with long-term changes in El Nino-Southern Oscillation variability, are the most likely driving forces behind millennial-scale shifts in lake level that reflect regional-scale changes in the moisture balance of the Atlantic-Amazon-Altiplano hydrologic system.
IS: 0165-0009
CP: Netherlands
DE: Palaeoclimatology; Palaeoclimatology
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-THE-QUATERNARY (71-3-2); GEOLOGICAL-ABSTRACTS: THE-QUATERNARY (72-7-2)
KW: insolation; water-budget; climate-change; Last-Glacial-Maximum; lake-level; proxy-climate-record
GE: South-America-Lake-Titicaca
PT: Journal; Article
RF: 61
AN: 2398700
UD: 200204
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 15 of 40 in GEOBASE 2001/12-2002/08

TI: Holocene vegetational and coastal environmental changes from the Lago Crispim record in northeastern Para State, eastern Amazonia .
AU: Behling-H.; Lima-Da-Costa-M.
AD: H. Behling, Center for Tropical Marine Ecology, Fahrenheitsstrasse 6, D28359 Bremen, Germany
EML: hbehling@zmt.uni-bremen.de
SO: Review-of-Palaeobotany-and-Palynology. 2001; 114(3-4): 145-155
PY: 2001
LA: English
LS: English
AB: Vegetational and coastal environmental changes have been interpreted from a 600 cm long and 7640 14C yr B.P. old sediment core from Lago Crispim located in the northeastern Para State in northern Brazil. The radiocarbon dated sediment core was studied by multi-element geochemistry, pollen and charcoal analysis. Holocene Atlantic sea-level rise caused an elevation of local water table, which allowed the formation of organic deposits in a probably former inter-dune valley. Dense, diverse and tall Amazon rain forest, and some restinga (coastal vegetation) covered the study area at the beginning of the record ar 7640 14C yr B.P. Mangrove vegetation developed along rivers close to the core site at that time. Subsequent decrease in less mangrove vegetation near the study site indicates a sea-level regression, beginning since around 7000 14C yr B.P. Lower sea-levels probably favoured the formation of a local Mauritia/Mauritiella palm swamp at 6620 14C yr B.P. Oscillations of higher and lower sea-level stands probably changed the size of the local palm swamp area several times between 6620 and 3630 14C yr B.P. Sea-level transgression at around 3630 14C yr B.P., caused marked coastal environmental changes: the development of mangroves near the site, the replacement of the local palm swamp by a Cyperaceae swamp, the substitution of the surrounding former Amazon rain forest and some restinga vegetation mainly by salt marshes. High amount carbonised particles suggest a strong human impact by burning on the coastal ecosystems during this late Holocene period. Highest concentrations of NaCl and also Ca, Mg and K in the upper sediment core indicate that the Atlantic was close during the late Holocene period. The core site, which is today 500 m from the coastline and only 1-2 m above modern sea-level, was apparently never reached by marine excursions during the Holocene. Less representation of mangrove since ca. 1840 14C yr B.P., may be related due to a slightly lower sea-level or to human impact in the study region. The modern shallow lake seems to be formed recently by road construction, forming an artificial dam. < copyright > 2001 Elsevier Science B.V. All rights reserved.
IS: 0034-6667
CP: Netherlands
DE: The-Holocene; The-Holocene
SC: GEOLOGICAL-ABSTRACTS: THE-QUATERNARY (72-7-7); GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-THE-QUATERNARY (71-3-7)
KW: Holocene; palynology; coastal-evolution; mangrove; sea-level-change; rainforest; saltmarsh
OD: Mauritia; Mauritiella
GE: Brazil-Para-State
PT: Journal; Article
RF: 24
AN: 2393361
UD: 200204
PI: S0034666701000446
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 16 of 40 in GEOBASE 2001/12-2002/08

TI: The state of water in Brazil-1999.
AU: De-Freitas-M.A.V.; Lima-J.E.F.W.; Ferreira-R.S.A.
AD: M.A.V. De Freitas, Brazilian Electricity Regulatory Age, SGAN 603 Modulo J Sala 105, Dist. Federal, Brasilia 70830-030, Brazil
EML: werneck@aneel.gov.br
SO: IAHS-AISH-Publication. 2001; -(272) : 145-150; See Barker Library - Stacks | GB651.I61 No.272
PY: 2001
LA: English
LS: English
AB: Brazil's water supply is about 187 170 m3 s-1, which means an annual volume of 5744 km3. However, the resource is distributed unevenly throughout the country. The East Atlantic Basin, for example, can supply only 1835 m3 year-1 per person, while the Amazon Basin can supply 628 938 m3 year-1 per person. Because conflicts involving water are becoming frequent in some areas of the country, the government is structuring a National System of Water Resources. Up-to-date information is a fundamental part of the process and, consequently, the Brazilian Electricity Regulatory Agency (ANEEL), in cooperation with other institutions, has published The State of Water in Brazil (1999), a book surveying the water resources of the country. The main objective of this paper is to provide information about the present state of water resources in Brazil, including political, social, economic, environmental, and technical data.
IS: 0144-7815
CP: United-Kingdom
DE: Water-Resources:-Planning; Water-resources-and-management; Water-supply-and-sanitation
SC: GEOGRAPHICAL-ABSTRACTS: HUMAN-GEOGRAPHY-ENVIRONMENTAL RESOURCES AND RESOURCES MANAGMENT (70-4-3-2); GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-HYDROLOGY (71-6-14); INTERNATIONAL-DEVELOPMENT-ABSTRACTS: WATER (74-13-2)
KW: water-supply; water-resource
GE: Brazil
PT: Journal; Article
RF: 4
AN: 2388502
UD: 200204
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 17 of 40 in GEOBASE 2001/12-2002/08

TI: Amazon river mainstem floodplain Landsat TM digital mosaic .
AU: Shimabukuro-Y.E.; Novo-E.M.; Mertes-L.K.
AD: Y.E. Shimabukuro, National Institute for Space Res., Remote Sensing Division, Av. dos Astronautas, 1758, Sao Jose dos Campos 12227-010, Brazil
EML: yosio@ltid.inpe.br
SO: International-Journal-of-Remote-Sensing. 2002 JAN 10; 23(1): 57-69
PY: 2002
LA: English
LS: English
AB: This paper presents the methodology used to build a Landsat Thematic Mapper (TM) digital mosaic for the Amazon River mainstem floodplain. Twenty-nine almost cloud-free TM Landsat scenes covering a period from 1985 to 1995 were selected from the National Institute for Space Research (INPE) archive. Most of the scenes were acquired from July to September, a period that begins with high waters and ends with receding water up to about the beginning of the low waters. Radiometric rectification was applied to the images to reduce variability of environmental conditions during Landsat TM data acquisition. The radiometric rectification applied had a good performance for bands 3, 5, and 7, for most of the scenes. For bands 1 and 2 the radiometric rectification was limited, especially for scenes with intense haze. Nevertheless, the overall performance of radiometric normalization allowed the production of a uniform dataset for the entire Brazilian Amazon River mainstem floodplain.
IS: 0143-1161
CP: United-Kingdom
DE: Fluvial-landforms
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-LANDFORMS (71-2-2)
KW: floodplain; Landsat-thematic-mapper; low-flow; data-acquisition; environmental-change
GE: South-America-Amazon-River
PT: Journal; Article
RF: 14
AN: 2385964
UD: 200204
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 18 of 40 in GEOBASE 2001/12-2002/08

TI: Spatial and temporal patterns of Amazon rainfall: Consequences for the planning of agricultural occupation and the protection of primary forests.
AU: Sombroek-W.
AD: Dr. W. Sombroek, ISRIC, P.O. Box 353, 6700 AJ Wageningen, Netherlands
EML: sombroek@isric.nl
SO: Ambio. 2001; 30(7): 388-396
PY: 2001
LA: English
LS: English
AB: The spatial and temporal pattern of annual rainfall and the strength of the dry season within the Amazon region are poorly known. Existing rainfall maps are based on the data from full-scale, long-term meteorological stations, operated by national organizations linked to the World Meteorological Organisation, such as INMET in Brazil. Stations with 30 or more years of uninterrupted and reliable recordings are very few, considering the size of the region, and most of them are located along the major rivers. It has been suggested that rainfall conditions away from these rivers are substantially different. An analysis has been made of the records of a network of simple pluviometric sites in the Brazilian part of the region as maintained by the National Agency for Electric Energy (ANEEL) since 1970. The latter data sets were used to draw more detailed maps on annual rainfall, and on the strength of the dry season in particular; average number of consecutive months with less than 100 mm, 50 mm, and 10 mm, respectively. Also, some data were obtained on the spatial expression of El Nino events within the region. Subregional differences are large, and it is argued that they are important for the success or failure of agricultural settlements; for the hazard of large-scale fire damage of the still existing primary forest vegetation; for the functioning of this land cover as stock and sink of CO<inf>2</inf>, and for the likelihood that secondary forests on abandoned agricultural lands will have less biomass. The effects of past El Nino rainfall anomalies on the biodiversity of the natural savannahs within the forest region are discussed.
IS: 0044-7447
CP: Sweden
DE: Precipitation-assessment
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-HYDROLOGY (71-6-1)
KW: rainfall; El-Nino; spatial-distribution; temporal-distribution
GE: Brazil-Amazonia
PT: Journal; Conference-Paper
RF: 61
AN: 2384053
UD: 200204
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 19 of 40 in GEOBASE 2001/12-2002/08

TI: Interannual variability of the rainy season and rainfall in the Brazilian Amazon Basin .
AU: Liebmann-B.; Marengo-J.A.
AD: B. Liebmann, Climate Diagnostic Center, R/CDCI, 325 Broadway, Boulder, CO 80303-3328, United States
EML: bl@cdc.noaa.gov
SO: Journal-of-Climate. 2001 NOV 15; 14(22): 4308-4318
PY: 2001
LA: English
LS: English
AB: Interannual variability of seasonal rainfall in the Brazilian Amazon basin is examined in context of its relationship to sea surface temperatures in the tropical Pacific and Atlantic Oceans. Linear correlations reveal strong relationships, but rainfall patterns are of regional scale. Areas of rainfall exhibiting strong relationships with SST are confined to the equatorial region of the Brazilian Amazon. The best relationships are found either during the season of transition between wet and dry regimes, or entirely within the dry season. It is hypothesized, and results are shown in support, that during the transition seasons, an important contributor to the SST control on seasonal totals is its influence on the timing on the rainy season onset or end. That influence appears to be stronger than the SST influence on the rainy season rain rate.
IS: 0894-8755
CP: United-States
DE: Air-sea-interaction; Air-sea-interaction
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-METEOROLOGY-AND-CLIMATOLOGY (71-7-8); OCEANOGRAPHIC-LITERATURE-REVIEW: MARINE-METEOROLOGY (76-2-5)
KW: annual-variation; rainfall; sea-surface-temperature; air-sea-interaction
GE: Brazil-Amazon-Basin; Pacific-Ocean-Tropical; Atlantic-Ocean-Tropical
PT: Journal; Article
RF: 27
AN: 2379178
UD: 200201
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 20 of 40 in GEOBASE 2001/12-2002/08

TI: True winter range of the Veery (Catharus fuscescens): Lessons for determining winter ranges of species that winter in the tropics.
AU: Remsen-J.V. Jr.
AD: J.V. Remsen Jr., Museum of Natural Science, Louisiana State University, Baton Rouge, LA 70803, United States
EML: najames@unix1.sncc.lsu.edu
SO: Auk. 2001; 118(4): 838-848
PY: 2001
LA: English
LS: English
AB: Most recent references describe the winter range of the Veery (Catharus fuscescens) as including an extensive area from northern Colombia, Venezuela, and Guyana south to south-central Brazil. Analysis of seasonal distribution of specimen records in South America, however, shows that 91 of 105 specimens were taken during spring and fall, not winter; the remaining 14, taken from 2 December to 20 February, are all from three small areas at the periphery or south of the Amazon basin. Thus, the true winter range is almost completely south and east of the area generally described. The seasonal distribution of specimen records is consistent with observational data from South America and banding data from the Neotropics. Although those data must be treated cautiously, it appears that the true winter range of the Veery is in south-central and southeastern Brazil, an area where habitat destruction threatens many natural habitats, rather than in the relatively undisturbed areas of western Amazonia. Widespread erroneous portrayal of the winter range of the Veery seems to have been caused largely by the assumption that the species winters in South America wherever it has been recorded and by overlooking a previously published analysis of its winter distribution.
IS: 0004-8038
CP: United-States
DE: Animal-ecology:-birds:-population-ecology
SC: ECOLOGICAL-ABSTRACTS: TERRESTRIAL-ECOLOGY (73-4-7-4-3)
KW: winter; migration; geographical-distribution
OD: Catharus-fuscescens
GE: South-America
PT: Journal; Article
RF: 73
AN: 2380359
UD: 200201
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 21 of 40 in GEOBASE 2001/12-2002/08

TI: How do tropical sea surface temperatures influence the seasonal distribution of precipitation in the equatorial Amazon?
AU: Fu-R.; Dickinson-R.E.; Chen-M.; Wang-H.
AD: Dr. R. Fu, Earth and Atmospheric Sciences, Georgia Institute of Technology, 221 Bobby Dodd Way, Atlanta, GA 30332-0340, United States
EML: fu@eas.gatech.edu
SO: Journal-of-Climate. 2001 OCT 15; 14(20): 4003-4026
PY: 2001
LA: English
LS: English
AB: Although the correlation between precipitation over tropical South America and sea surface temperatures (SSTs) over the Pacific and Atlantic has been documented since the early twentieth century, the impact of each ocean on the timing and intensity of the wet season over tropical South America and the underlying mechanisms have remained unclear. Numerical experiments have been conducted using the National Center for Atmospheric Research Community Climate Model Version 3 to explore these impacts. The results suggest the following. 1) Seasonality of SSTs in the tropical Pacific and Atlantic has an important influence on precipitation in the eastern Amazon during the equinox seasons. The eastern side of the Amazon is influenced both by the direct thermal circulation of the Atlantic intertropical convergence zone (ITCZ) and by Rossby waves. These processes are enhanced by the seasonal cycles of SSTs in the tropical Atlantic and Pacific. SSTs affect Amazon precipitation much less during the solstice seasons and in the western Amazon. 2) The seasonality of SSTs in the Atlantic more strongly affects Amazon rainfall than does that of the Pacific. Without the former, austral spring in the eastern equatorial Amazon would be a wet season, rather than the observed dry season. As a consequence of the lag at that time of the southward seasonal migration of the Atlantic SSTs behind that of the insolation, the Atlantic ITCZ centers itself near 10< degrees >N, instead of at the equator, imposing subsidence and low-level anticyclonic flow over the eastern equatorial Amazon, thus drying the air above the planetary boundary layer and reducing the low-level moisture convergence. Consequently, convection in the eastern Amazon is suppressed despite strong surface heating. 3) Seasonality of the SSTs in the tropical Pacific also tends to reduce precipitation in the eastern Amazon during both spring and fall. In spring, subsidence is enhanced not only through a zonal direct circulation, but also through Rossby waves propagating from the extratropical South Pacific to subtropical South America. This teleconnection strengthens the South Atlantic convergence zone (SACZ) and the Nordeste low, in both cases reducing precipitation in the eastern Amazon. A direct thermal response to the Pacific SSTs enhances lower-level divergence and reduces precipitation from the northern tropical Atlantic to the northeastern Amazon.
IS: 0894-8755
CP: United-States
DE: Air-sea-interaction; Air-sea-interaction
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-METEOROLOGY-AND-CLIMATOLOGY (71-7-8); OCEANOGRAPHIC-LITERATURE-REVIEW: MARINE-METEOROLOGY (76-2-5)
KW: tropical-environment; sea-surface-temperature; seasonal-variation; precipitation-assessment; air-sea-interaction
GE: Pacific-Ocean-Tropical; Atlantic-Ocean-Tropical; South-America-Amazon
PT: Journal; Article
RF: 45
AN: 2371101
UD: 200201
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 22 of 40 in GEOBASE 2001/12-2002/08

TI: Onset and end of the rainy season in the Brazilian Amazon Basin .
AU: Marengo-J.A.; Liebmann-B.; Kousky-V.E.; Filizola-N.P.; Wainer-I.C.
SO: Journal-of-Climate. 2001 MAR 01; 14(5): 833-852
PY: 2001
LA: English
LS: English
AB: Onset and end of the rainy season in the Amazon Basin are examined for the period 1979-96. The onset and end dates are determined by averaging daily rainfall data from many stations, and then constructing 5-day averages (pentads). Onset (end) is defined as the pentad in which rainfall exceeds (falls below) a given threshold, provided that average rainfall was well below (above) the threshold for several pentads preceding onset (end), and well above (below) the threshold for several pentads after onset (end). For the criteria chosen, the climatological onset progresses toward the southeast, arriving in mid-October, and then toward the mouth of the Amazon, arriving near the end of the year. The end dates are earliest in the southeast and progress toward the north, but withdrawal is slower than onset. The onset dates, however, are quite sensitive to changes in the threshold. If the threshold is doubled, for example, the sense of onset is reversed, with onset occurring toward the northwest. Changes in threshold do not change the direction of the progression of the end of the rainy season. The central Amazon shows the largest variation in the date of onset. In several years, onset in the southeast occurs before that in the central Amazon, but onset near the mouth is always latest. There is an unexpectedly low relationship between the length of the rainy season and total accumulation. Likewise, there is little relationship between the onset (and end) date and the total accumulation. Composites of outgoing longwave radiation and the low-level wind field show that in the central Amazon, onset is associated with an anomalous anticyclone and enhanced trade winds in the Atlantic. Near the mouth of the Amazon, however, onset is associated with large-scale northerly anomalies, and the zonal component of the trade winds is reduced. There is an apparent association between sea surface temperature anomalies in the tropical Atlantic and Pacific and the pentads of onset and end of the rainy season in the northern and central Amazon, and near its mouth. The sense is that a warm Pacific and cold Atlantic result in a delayed onset and early withdrawal. Although the strong El Nino of 1982/83 and La Nina 1988/89 were examples of a delayed and early onset, respectively, the relationships it still holds these years are not considered.
IS: 0894-8755
CP: United-States
DE: Regional-weather-patterns
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-METEOROLOGY-AND-CLIMATOLOGY (71-7-5)
KW: precipitation-climatology-; annual-variation; climatology; atmospheric-circulation
GE: Brazil-Amazon
PT: Journal; Article
RF: 46
AN: 2370562
UD: 200201
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 23 of 40 in GEOBASE 2001/12-2002/08

TI: Landscape change in tidal floodplains near the mouth of the Amazon River.
AU: Zarin-D.J.; Pereira-V.F.G.; Raffles-H.; Rabelo-F.G.; Pinedo-Vasquez-M.; Congalton-R.G.
AD: D.J. Zarin, Sch. Forest Resources/Conservation, University of Florida, P.O. Box 110760, Gainesville, FL 32611, United States
EML: zarin@ufl.edu
SO: Forest-Ecology-and-Management. 2001 DEC 01; 154(3): 383-393
PY: 2001
LA: English
LS: English
AB: Recent analyses of human impacts on Amazonian landscapes have focused primarily on upland forests that have been deforested as roads have penetrated the frontier. In contrast, relatively little priority has been given to documenting and understanding landscape changes in the roughly 400 000 km2 of Amazonia's floodplains, where an extensive network of waterways has long provided the transportation infrastructure. Amazonian floodplains generally support higher rural population densities than the uplands and provide critical habitat and food for fish and shrimp species, a principal source of protein for millions of rural and urban Amazonians. We examined cover type changes in a 52 304 ha tidal floodplain near the mouth of the Amazon River in Amapa, Brazil (tidal range = 2-3 m). We found five major cover types discernible in both black-and-white infrared aerial photographs taken in October-November 1976, and Landsat Thematic Mapper (TM) data from November 1991. The cover types were: (1) water and unvegetated banks, (2) herbaceous cover, both natural and agricultural, (3) early regrowth or degraded forest, (4) palm forest, and (5) mixed species varzea forest. From 1976 to 1991, the areal extent of the aquatic, herbaceous, early regrowth and degraded forest, and palm forest cover types increased from 2833 to 3406, 10708 to 15074, 3842 to 5446, and 1250 to 3208 ha, respectively, while the areal extent of the mixed species varzea forest decreased from 33 671 to 25 170 ha. Logging, heart-of-palm extraction and agricultural conversion are interacting disturbances which, combined with the rapid regrowth that occurs in the tidal floodplains of Amazonia, have produced a landscape characterized by a high rate of cover type transitions and a substantial loss of the mixed species varzea forest. The annualized forest conversion rate is comparable to that reported elsewhere for upland Amazonian landscapes. < copyright > 2001 Elsevier Science B.V. All rights reserved.
IS: 0378-1127
CP: Netherlands
DE: Regional
SC: ECOLOGICAL-ABSTRACTS: NATURE-CONSERVATION (73-8-3)
KW: GIS; floodplain-forest; land-cover; landscape-change; landscape-ecology; remote-sensing
GE: Brazil-Amapa-State
PT: Journal; Article
RF: 37
AN: 2374797
UD: 200201
PI: S0378112701005102
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 24 of 40 in GEOBASE 2001/12-2002/08

TI: The altitude effect on the isotopic composition of tropical rains .
AU: Gonfiantini-R.; Roche-M.-A.; Olivry-J.-C.; Fontes-J.-C.; Zuppi-G.M.
AD: R. Gonfiantini, Ist. Geocron. Geochim. Isotopica, Area della Ricerca di Pisa, Via G. Moruzzi 1, Pisa 56124, Italy
EML: R.Gonfiantini@iggi.pi.cnr.it
SO: Chemical-Geology. 2001; 181(1-4): 147-167
PY: 2001
LA: English
LS: English
AB: Data on the Isotopic composition of yearly and monthly precipitation samples collected at various altitudes on Mount Cameroon, Africa, and in two transects from the Amazon to the Altiplano in Bolivia, South America, are presented. In Bolivia, the 2H/1H and 18O/16O ratios show seasonal variations, with lower values in the summer rainy months with respects to the winter dry ones. The < delta >2H and < delta >18O values are linearly correlated with a slope of 7.5 in all seasons, but the intercept is higher in winter than in summer. The < delta >-gradient vs. altitude is larger in rainy periods. The isotopic data are fitted by using a numerical model based on Rayleigh adiabatic condensation process. Model simulations show that the < delta >-altitude relationship slightly deviates from linearity, because the slope increases with altitude due to the lowering of temperature and the consequent increase of the condensation rate of atmospheric vapour. The parameters which most affect the shape of < delta >-altitude relationships are the temperature vertical gradient (lapse rate) and the initial relative humidity of the ascending air masses, while a change of the initial isotopic composition of water vapour determines a shift of the curve along the < delta >-axis. In addition, the model explains the observed increase of the deuterium excess with altitude. < copyright > 2001 Elsevier Science B.V. All rights reserved.
IS: 0009-2541
CP: United-Kingdom
DE: Hydrochemistry; Precipitation-quality
SC: GEOLOGICAL-ABSTRACTS: GEOCHEMISTRY (72-2-4); GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-HYDROLOGY (71-6-2)
KW: tropical-meteorology; rainfall; precipitation-quality; water-chemistry; isotopic-composition; altitude
GE: Africa; South-America
PT: Journal; Article
RF: 38
AN: 2369577
UD: 200201
PI: S0009254101002790
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 25 of 40 in GEOBASE 2001/12-2002/08

TI: Cloud cover in Landsat observations of the Brazilian Amazon .
AU: Asner-G.P.
AD: G.P. Asner, Dept. Geol. Sci. Envrn. Stud. Prog., University of Colorado, Boulder, CO 80309, United States
EML: gregory.asner@colorado.edu
SO: International-Journal-of-Remote-Sensing. 2001 DEC 15; 22(18): 3855-3862
PY: 2001
LA: English
LS: English
AB: High spatial resolution Landsat imagery is employed in efforts to understand the impact of human activities on ecological, biogeochemical and atmospheric processes in the Amazon basin. The utility of Landsat multi-spectral data depends both on the degree to which surface properties can be estimated from the radiometric measurements and on the ability to observe the surface through the atmosphere. Clouds are a major obstacle to optical remote sensing of humid tropical regions, therefore cloud cover probability analysis is a fundamental prerequisite to land-cover change and Earth system process studies in these regions. This paper reports the results of a spatially explicit analysis of cloud cover in the Landsat archive of Brazilian Amazonia from 1984 to 1997. Monthly observations of any part of the basin are highly improbable using Landsat-like optical imagers. Annual observations are possible for most of the basin, but are improbable in northern parts of the region. These results quantify the limitations imposed by cloud cover to current Amazon land-cover change assessments using Landsat data. They emphasize the need for improved radar and alternative optical data fusion techniques to provide time-series analyses of biogeophysical properties for regional modelling efforts.
IS: 0143-1161
CP: United-Kingdom
DE: Applications:-atmosphere
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-REMOTE-SENSING-GIS-AND-MAPPING (71-8-8-1)
KW: cloud-cover; Landsat-multispectral-scanner; land-use-change
GE: Brazil-Amazon
PT: Journal; Article
RF: 17
AN: 2369067
UD: 200201
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 26 of 40 in GEOBASE 2001/12-2002/08

TI: RADARSAT-1 image quality and calibration - A continuing success.
AU: Srivastava-S.K.; Hawkins-R.K.; Banik-B.T.; Adamovic-M.; Gray-R.; Murnaghan-K.; Lukowski-T.I.; Jefferies-W.C.
AD: S.K. Srivastava, Satellite Operations, Canadian Space Agency, 6767 Route de l'Aeroport, Saint-Hubert, QC J3Y 8Y9, Canada
SO: Advances-in-Space-Research. 2001; 28(1): 99-108
PY: 2001
LA: English
LS: English
AB: The Canadian earth observation satellite, RADARSAT-1 was launched on November 4, 1995 with the first image acquired on November 28 of that year. After commissioning it was put into routine operation on April 1, 1996. Since then more than four years of successful operation have been completed, utilizing data for their intended applications. Significant effort has been extended in the provision of radiometrically and geometrically calibrated products to users by the Canadian Data Processing Facility (CDPF). Particular emphasis has been on the maintenance of image quality and calibration as monitored using images of the Amazon Rainforest and of the RADARSAT-1 Precision Transponders (RPT). This first part of the paper will review the image quality and calibration evolution of RADARSAT-1, complementing previously presented reviews on this subject. Data will be given on various image quality parameters related to impulse response, location error, antenna pattern and noise equivalent measures, and on calibration accuracy as achieved to date. Recent work on calibration and image quality improvements for ScanSAR products are also presented. The latter part of the paper describes methodologies developed for maintenance of radiometric calibration performance of RADARSAT-1, including a statistical technique useful for early detection of radiometric problems associated with single calibrated beams. < copyright > 2001 COSPAR. Published by Elsevier Science Ltd. All rights reserved.
IS: 0273-1177
CP: United-Kingdom
DE: Remote-sensing:-primary-data-capture
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-REMOTE-SENSING-GIS-AND-MAPPING (71-8-5-1)
KW: image-analysis; calibration; RADARSAT; EOS
PT: Journal; Article
RF: 14
AN: 2368023
UD: 200201
PI: S0273117701003052
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 27 of 40 in GEOBASE 2001/12-2002/08

TI: Landscape degradation in the XI<inf>th</inf> region of Chile within the framework of growing environmental problems in western Patagonia.
OT: Landschaftsdegradation in der XI. region chiles vor dem hintergrund wachsender umweltproleme in westpatagonien - ein geookologischer und geostatistischer ansatz.
AU: Vott-A.; Endlicher-W.
AD: Dr. A. Vott, Fachbereich Geogr./Phillips-Univ., Deutschhausstr. 10, Marburg D-35032, Germany
EML: voett@aol.com
SO: Erde. 2001; 132(3): 239-268
PY: 2001
LA: English; German
LS: English; German
AB: Together with the Amazon Basin the 'Southern Cone' of South America is the less populated part of the continent and far away of the Argentine and Chilean capitals of Buenos Aires and Santiago de Chile. Nevertheless, even in this remote parts environmental problems and processes of landscape degradation are more and more evident. Soil erosion processes due to overgrazing started in Argentine Eastern Patagonia at least at the end of the 19th century with the introduction of sheep from the Falkland Islands (Endlicher 1991; Baruth, Endlicher and Hoppe 1998). Chilean Western Patagonia with its archipelagos, fjords, channels, mountain ranges and ice caps, however, has been considered until now as a sanctuary for virgin temperate rain forests, untouched coasts, clean air and beautiful lakes, the 'last frontier of America'. A closer evaluation of the natural potential, the natural hazards as well as the human impacts shows a growing number of problems with a clear west-east differentiation. Larger environmental impacts in Western Patagonia were initiated by the colonization programs of the chilean government only about 70 years ago (Weischet 1970, Borsdorf 1987). The main aspect of this paper deals with landscape degradation in the drainage area of Rio Coyhaique, east of the region's capital, which is responsible for extensive losses of soil resources and therefore the source of strong economic, above all agricultural problems. The results of geoecological and geostatistical investigations allow to register degradation forms and processes as well as, by means of discriminant analysis, to locate landscape areas with a high potential for future degradation.
IS: 0013-9998
CP: Germany
DE: Nature-Society-Relations; Erosion-and-Conservation; Land-degradation,-reclamation-and-erosion-control
SC: GEOGRAPHICAL-ABSTRACTS: HUMAN-GEOGRAPHY-ENVIRONMENT (70-3-2); GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-SOILS (71-5-15); INTERNATIONAL-DEVELOPMENT-ABSTRACTS: ENVIRONMENT-AND-DEVELOPMENT (74-2-3)
KW: land-degradation; environmental-degradation; nature-society-relations; soil-erosion
GE: Chile-Patagonia
PT: Journal; Article
RF: 46
AN: 2367461
UD: 200201
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 28 of 40 in GEOBASE 2001/12-2002/08

TI: Atmospheric circulation features associated with rainfall variability over Southern Northeast Brazil.
AU: Chaves-R.R.; Cavalcanti-I.F.A.
AD: Dr. I.F.A. Cavalcanti, INPE/CPTEC Rod. Pres. Dutra., C. Paulista, SP 12630-000, Brazil
EML: iracema@cptec.inpe.br
SO: Monthly-Weather-Review. 2001; 129(10): 2614-2626
PY: 2001
LA: English
LS: English
AB: The atmospheric circulation features associated with rainfall variability during the main rainy period of the region of southern Northeast Brazil (sNEB) are determined through principal components analysis and cluster analysis. Daily rainfall, NCEP reanalysis, and OLR data are used from 1979 to 1997. The analyses are performed considering a large area including South America and the Pacific and Atlantic Oceans and also considering a regional area over tropical South America. The influence of synoptic systems, as well as the phenomena associated with their variability, such as El-Nino-Southern Oscillation (ENSO) and baroclinic waves over the Pacific Ocean and South America are discussed. Positive (negative) rainfall anomalies over sNEB are related to cold (warm) episodes in the tropical Pacific. On the intraseasonal timescale there are interrelationships among the South Atlantic convergence zone (SACZ), Bolivian high, and the northeast upper-cyclonic vortex. It is noted that rainy periods in sNEB are associated with a northward displacement of the SACZ. an upper-level cyclonic vortex situated over the Atlantic Ocean, intense convection over the eastern Amazon, and an eastward shift in the position of the Bolivian high. At low levels the flow is directed from the Amazon toward the sNEB and there is a shift of the South Atlantic subtropical anticyclone eastward with a weakening of the southeast trade winds over the northeast coast. The dry pattern is associated with a southward displacement of the SACZ, an upper-level cyclonic vortex either close to or over the continent, and a westward displacement of the Bolivian high. In this case, the low-level flow is directed from the Amazon to the south and there is a strengthening and/or westward shift of the South Atlantic anticyclone with an intensification of the southeast trade winds along the northeast coast.
IS: 0027-0644
CP: United-States
DE: Dynamic-meteorology:-mesoscale
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-METEOROLOGY-AND-CLIMATOLOGY (71-7-9-2)
KW: atmospheric-circulation; rainfall; spatial-variation; principal-component-analysis; cluster-analysis; baroclinic-wave; El-Nino-Southern-Oscillation
GE: Brazil-Northeast; South-America; Pacific-Ocean; Atlantic-Ocean
PT: Journal; Article
RF: 39
AN: 2365561
UD: 200201
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 29 of 40 in GEOBASE 2001/12-2002/08

TI: Regional variability in tropical convection: Observations from TRMM.
AU: Petersen-W.A.; Rutledge-S.A.
AD: Dr. W.A. Petersen, Department of Atmospheric Science, Colorado State University, Fort Collins, CO 80523-1371, United States
EML: walt@radarmet.atmos.colostate.edu
SO: Journal-of-Climate. 2001 SEP 01; 14(17): 3566-3586
PY: 2001
LA: English
LS: English
AB: Observation of the vertical profile of precipitation over the global Tropics is a key objective of the Tropical Rainfall Measuring Mission (TRMM) because this information is central to obtaining vertical profiles of latent heating. This study combines both TRMM precipitation radar (PR) and Lightning Imaging Sensor (LIS) data to examine "wet-season" vertical structures of tropical precipitation across a broad spectrum of locations in the global Tropics. TRMM-PR reflectivity data (2A25 algorithm) were utilized to produce seasonal mean three-dimensional relative frequency histograms and precipitation ice water contents over grid boxes of approximately 5< degrees >-10< degrees > in latitude and longitude. The reflectivity histograms and ice water contents were then combined with LIS lightning flash densities and 2A25 mean rainfall rates to examine regional relationships between precipitation vertical structure, precipitation processes, and lightning production. Analysis of the reflectivity vertical structure histograms and lightning flash density data reveals that 1) relative to tropical continental locations, wet-season isolated tropical oceanic locations exhibit relatively little spatial (and in some instances seasonal) variability in vertical structure across the global Tropics; 2) coastal locations and areas located within 500-1000 km of a continent exhibit considerable seasonal and spatial variability in mean vertical structure, often resembling "continental" profiles or falling intermediate to that of tropical continental and isolated oceanic regimes; and 3) interior tropical continental locations exhibit marked variability in vertical variability in vertical structure both spatially and seasonally, exhibiting a continuum of characteristics ranging from a near-isolated oceanic profile observed over the central Amazon and India to a more robust continental profile observed over regions such as the Congo and Florida. Examination of regional and seasonal mean conditional instability for a small but representative subset of the geographic locations suggests that tropospheric thermodynamic structure likely plays a significant role in the regional characteristics of precipitation vertical structure and associated lightning flash density. In general, the largest systematic variability in precipitation vertical structure observed between all of the locations examined occured above the freezing level. It is important that subfreezing temperature variability in the vertical reflectivity structures was well reflected in the seasonal mean lightning flash densities and ice water contents diagnosed for each location. In turn, systematically larger rainfall rates were observed on a pixel-by-pixel basis in locations with larger precipitation ice water content and lightning flash density. These results delineate, in a regional sense, the relative importance of mixed-phase precipitation production across the global Tropics.
IS: 0894-8755
CP: United-States
DE: Synoptic-meteorology
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-METEOROLOGY-AND-CLIMATOLOGY (71-7-6)
KW: regional-climate; convection; vertical-profile; precipitation-climatology-; lightning; thermodynamics
GE: India; United-States-Florida; Congo
PT: Journal; Article
RF: 93
AN: 2363882
UD: 200201
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 30 of 40 in GEOBASE 2001/12-2002/08

TI: Nutrient fluxes in rainfall, throughfall and stemflow in tree-based land use systems and spontaneous tree vegetation of central Amazonia.
AU: Schroth-G.; Elias-M.E.A.; Uguen-K.; Seixas-R.; Zech-W.
AD: G. Schroth, Biol. Dynam. Forest Fragments Proj., Natl. Inst. for Res. in the Amazon, C.P. 478, 69011-970 Manaus-AM, Brazil
EML: schroth@internext.com.br
SO: Agriculture-Ecosystems-and-Environment. 2001; 87(1): 37-49
PY: 2001
LA: English
LS: English
AB: The quantification of nutrient fluxes is an important step in the development of sustainable land use systems, especially on low-fertility soils of the humid tropics. Nutrient concentrations in rainfall (RF), throughfall (TF) and stemflow (SF) were measured for ten rainfall events in a polyculture (multi-strata agroforestry system) composed of five tree crops, three tree crop monocultures, spontaneous tree fallow and two rainforest tree species in central Amazonia and nutrient fluxes were calculated for a 1 year period. Nutrient inputs in wet deposition during 1 year were 5.5 kg ha-1 of total N, of which 42% were in the organic form, 0.07 kg ha-1 of total P, of which 71% were in the organic form, 2.6 kg ha-1 of K, 0.8 kg ha-1 of Ca and 0.3 kg ha-1 of Mg. The nutrient concentrations in TF and SF were influenced by tree species, land use system, nutrient status of the trees and size of the rain events. The rainforest species had high N but low P concentrations in their TF and SF. The highest P concentrations were measured in SF of annatto (Bixa orellana), which was 115 times richer in total P and 400 times richer in phosphate-P than RF for small rain events. Higher fertilizer application increased the concentrations of P and Mg in TF and SF. On the plot level, the nutrient fluxes in TF and SF were greatest in the systems with the highest plant density and crown cover (fallows and palm monocultures). On the species level, strong increases of the nutrient fluxes in TF and SF were observed close to the stem of certain trees compared with the plot average (more than 10 fold for P, K and Mg under peach palm Bactris gasipaes). In the polycultures and the fallow, the recycling of N, P, Ca and Mg in TF and SF was about 5-10% of the total recycling including litterfall, but was 50-53% for K (77% in the peach palm monocultures). Throughfall and SF are most relevant for K cycling and by influencing small-scale patterns of nutrient inputs into the soil. Stemflow is especially important in vegetation with high stem density, such as certain fallows and in systems dominated by palms. These results can help to devise measurement programs for nutrient cycling in tree-dominated land use systems and spontaneous vegetation in the humid tropics. Possible effects of concentrated nutrient solutions on microbial processes in soil and litter merit further investigation. < copyright > 2001 Elsevier Science B.V. All rights reserved.
IS: 0167-8809
CP: Netherlands
DE: Biogeochemical-cycles
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-SYNOPTIC-GEOGRAPHY (71-1-3)
KW: rainfall; throughfall; stemflow; land-use; nutrient-cycling
OD: Bixa-orellana; Bactris-gasipaes
GE: South-America-Amazonia
PT: Journal; Article
RF: 27
AN: 2365001
UD: 200201
PI: S0167880900002942
CN: Copyright 2002 Elsevier Science Ltd. All rights reserved.
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Record 31 of 40 in GEOBASE 1997/12-2001/11

TI: Effect of sub-grid-scale variability of soil moisture and precipitation intensity on surface runoff and streamflow.
AU: Arora-V.K.; Chiew-F.H.S.; Grayson-R.B.
AD: V.K. Arora, Canadian Centre/Climate Modelling, Meteorological Service of Canada, University of Victoria, PO Box 1700, Victoria, BC V8W 2Y2, Canada
EML: vivek.arora@ec.gc.ca
SO: Journal-of-Geophysical-Research-D:-Atmospheres. 2001; 106(15): 17073-17091
PY: 2001
LA: English
LS: English
AB: Land surface scheme simulations, which differ only in their parameterization of surface runoff, are performed for the Amazon and Mississippi River basins at < similar-to > 1.88< degrees > x 1.90< degrees > resolution. In the first simulation, soil moisture and precipitation intensity are assumed to be uniformly distributed. In the second simulation, precipitation intensity is assumed to be exponentially distributed, and soil moisture subgrid variability is expressed in terms of the variable water-holding capacity of the grid cell. The effect of subgrid variability of precipitaiton intensity and soil moisture is taken into account to model surface runoff more realistically. National Center for Environmental Prediction (NCEP) reanalysis data with its precipitation estimates adjusted to long-term values are used to drive the land surface scheme, and flow routing is performed to obtain streamflow at three locations in each river basin. Comparisons with observations indicate that the inclusion of subgrid variability results in slightly improved streamflow simulations in terms of reduced root-mean-square errors and better correlation coefficients. Sub-grid-scale variability also results in significant changes in the magnitude, time, and frequency of surface runoff generation, partitioning of total runoff into surface runoff and drainage and slightly drier soil moisture conditions.
IS: 0148-0227
CP: United-States
DE: Runoff,-streamflow-and-basins
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-HYDROLOGY (71-6-5)
KW: soil-moisture; precipitation-intensity; runoff; streamflow
PT: Journal; Article
RF: 75
AN: 2356952
UD: 200110
CN: Copyright 2001 Elsevier Science Ltd. All rights reserved.
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Record 32 of 40 in GEOBASE 1997/12-2001/11

TI: Tectonics and paleogeography along the Amazon river.
AU: Costa-J.B.S.; Bemerguy-R.L.; Hasui-Y.; da-Silva-Borges-M.
AD: J.B.S. Costa, Centro de Geociencias, Departamento de Geologia, Universidade Federal do Para, P.O. Box 1611, Belem, PA 66.075-900, Brazil
EML: jsena@ufpa.br
SO: Journal-of-South-American-Earth-Sciences. 2001; 14(4): 335-347
PY: 2001
LA: English
LS: English
AB: The main structural and geomorphological features along the Amazon River are closely associated with Mesozoic and Cenozoic tectonic events. The Mesozoic tectonic setting is characterised by the Amazonas and Marajo Basins, two distinct extensional segments. The Amazonas Basin is formed by NNE-SSW normal faults, which control the emplacement of dolerite dykes and deposition of the sedimentary pile. In the more intense tectonic phase (mid-Late Cretaceous), the depocentres were filled with fluvial sequences associated with axial drainage systems, which diverge from the Lower Tapajos Arch. During the next subsidence phase, probably in the Early Tertiary, and under low rate extension, much of the drainage systems reversed, directing the paleo-Amazon River to flow eastwards. The Marajo Basin encompasses NW-SE normal faults and NE-SW strike-slip faults, with the latter running almost parallel to the extensional axes. The normal faults controlled the deposition of thick rift and post-rift sequences and the emplacement of dolerite dykes. During the evolution of the basin, the shoulder (Gurupa Arch) became distinct, having been modelled by drainage systems strongly controlled by the trend of the strike-slip faults. The Arari Lineament, which marks the northwest boundary of the Marajo Basin, has been working as a linkage corridor between the paleo and modern Amazon River with the Atlantic Ocean. The neotectonic evolution since the Miocene comprises two sets of structural and geomorphological features. The older set (Miocene-Pliocene) encompasses two NE-trending transpressive domains and one NW-trending transtensive domain, which are linked to E-W and NE-SW right-lateral strike-slip systems. The transpressive domains display aligned hills controlled by reverse faults and folds, and are separated by large plains associated with pull-apart basins along clockwise strike-slip systems (e.g. Tupinambarana Lineament). Many changes were introduced in the landscape by the transpressive and transtensive structures, such as the blockage of major rivers, which evolved to river-lakes, transgression of the sea over a large area in the Marajo region, and uplift of long and narrow blocks that are oblique to the trend of the main channel. The younger set (Pliocene-Holocene) refers to two triple-arm systems of rift/rift/strike-slip and strike-slip/strike-slip/rift types, and two large transtensive segments, which have controlled the orientation of the modern drainage patterns. < copyright > 2001 Elsevier Science Ltd. All rights reserved.
IS: 0895-9811
CP: United-Kingdom
DE: Regional-structure-and-tectonics
SC: GEOLOGICAL-ABSTRACTS: STRUCRURAL-GEOLOGY-AND-TECTONICS (72-10-2)
KW: paleogeography; Mesozoic; Cenozoic; tectonic-evolution; fluvial-geomorphology; neotectonics
GE: South-America-Amazon-River
PT: Journal; Article
RF: 42
AN: 2353157
UD: 200110
PI: S0895981101000256
CN: Copyright 2001 Elsevier Science Ltd. All rights reserved.
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Record 33 of 40 in GEOBASE 1997/12-2001/11

TI: Cloud condensation nuclei in the Amazon Basin: "Marine" conditions over a continent?
AU: Roberts-G.C.; Andreae-M.O.; Zhou-J.; Artaxo-P.
AD: G.C. Roberts, Biogeochemistry Department, Max Planck Institute for Chemistry, P.O. Box 3060, Mainz D-55020, Germany
SO: Geophysical-Research-Letters. 2001 JUL 15; 28(14): 2807-2810
PY: 2001
LA: English
LS: English
AB: Cloud condensation nuclei (CCN) are linked to radiative forcing, precipitation, and cloud structure; yet, their role in tropical climates remains largely unknown. CCN concentrations (N<inf>CCN</inf>) measured during the wet season in the Amazon Basin were surprisingly low (mean N<inf>CCN</inf> at 1% supersaturation: 267 ± 132 cm-3) and resembled concentrations more typical of marine locations than most continental sites. At low background CCN concentrations, cloud properties are more sensitive to an increase in N<inf>CCN</inf>. Therefore, enhanced aerosol emissions due to human activity in the Amazon Basin may have a stronger impact on climate than emissions in other continental regions. In spite of the large organic fraction in the Amazonian aerosol, a detailed analysis of number distributions and size-dependent chemical composition indicates that sulfate plays an important role in CCN activity.
IS: 0094-8276
CP: United-States
DE: Aerosols
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-METEOROLOGY-AND-CLIMATOLOGY (71-7-15)
KW: cloud-condensation-nucleus; tropical-meteorology; aerosol; climate-forcing; sulfate
GE: South-America-Amazon-Basin
PT: Journal; Article
RF: 25
AN: 2349543
UD: 200110
CN: Copyright 2001 Elsevier Science Ltd. All rights reserved.
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Record 34 of 40 in GEOBASE 1997/12-2001/11

TI: Water level changes in a large Amazon lake measured with spaceborne radar interferometry and altimetry.
AU: Alsdorf-D.; Birkett-C.; Dunne-T.; Melack-J.; Hess-L.
AD: D. Alsdorf, ICESS/Bren School of Env. Sci/Mgmt., UCSB, Santa Barbara, CA 93106, United States
EML: alsdorf@geog.ucla.edu
SO: Geophysical-Research-Letters. 2001 JUL 15; 28(14): 2671-2674
PY: 2001
LA: English
LS: English
AB: We demonstrate that interferometric processing of JERS-1 SAR data over an Amazon lake containing ~1500 islands yields centimeter-scale changes in the height of the water surface from February 14 to March 30, 1997. For the method to work, we qualitatively find that inundation of about one or two leafless trees per 25 m2 multi-look SAR pixel is sufficient to return the radar pulse to the side-looking antenna. Validation is provided by multi-temporal TOPEX-POSEIDON altimetry profiles, which directly measure surface heights relative to a fixed datum. Because SAR provides an image, the water height changes (~12 cm) can be converted to a net volume measurement (280 million m3) over the 44 days separating the JERS-1 acquisitions. Compared to historical gauge records, removal of this volume from the lake required a ~50% greater flow.
IS: 0094-8276
CP: United-States
DE: Applications:-hydrosphere
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-REMOTE-SENSING-GIS-AND-MAPPING (71-8-8-4)
KW: lake-level; interferometry; altimetry; satellite-altimetry; synthetic-aperture-radar
GE: South-America-Amazonia-Lake-Balbina
PT: Journal; Article
RF: 13
AN: 2349509
UD: 200110
CN: Copyright 2001 Elsevier Science Ltd. All rights reserved.
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Record 35 of 40 in GEOBASE 1997/12-2001/11

TI: Alternative successional pathways in the Amazon Basin.
AU: Mesquita-R.C.G.; Ickes-K.; Ganade-G.; Williamson-G.B.
AD: R.C.G. Mesquita, PDBFF-INPA, Cx. P. 478, Manaus-Amazonas 69083-970, Brazil
EML: rita@buriti.com.br
SO: Journal-of-Ecology. 2001; 89(4): 528-537
PY: 2001
LA: English
LS: English
AB: 1. Successional pathways were evaluated in two Amazonian secondary forest communities with different land-use histories. Sites which had been clearcut without subsequent use were dominated after 6-10 years by the pioneer genus Cecropia (Moraceae), whereas those used for pasture before abandonment were dominated by the pioneer genus Vismia (Clusiaceae). 2. There were 58 plant families and 300 species identified in Cecropia stands but only 43 families and 147 species were identified in Vismia stands. There were 77 species in common (Sorensen similarity = 0.34). 3. Differences in species number and composition of recruiting individuals between stand types were significant and were a function of the dominant pioneer genus, stem density, distance from primary forest, and land-use history. Regeneration under Vismia canopy was dominated by small Vistula individuals (25% of plants < 2 cm basal diameter), whereas regeneration under Cecropia canopy was more diverse and did not include a single young Cecropia. 4. The number of regenerating plants in both secondary stand types dropped off sharply with distance (5, 25, 50, and 100 m) from primary forest, suggesting that seed dispersal was limiting plant recruitment. Species richness also declined with distance and could be explained by the decline in plant density. Species richness in Cecropia stands increased linearly with plant density, but in Vismia stands the richness increase with density was a decelerating function. 5. For the central Amazon, secondary succession involves a more rapid return of primary forest species if deforestation is not followed by use as pasture before abandonment.
IS: 0022-0477
CP: United-Kingdom
DE: Plant-ecology:-communities
SC: ECOLOGICAL-ABSTRACTS: TERRESTRIAL-ECOLOGY (73-4-6-6)
KW: succession; secondary-forest; community-composition; regeneration; species-richness
OD: Cecropia; Vismia
GE: Brazil-Amazon-Basin
PT: Journal; Article
RF: 43
AN: 2354576
UD: 200110
CN: Copyright 2001 Elsevier Science Ltd. All rights reserved.
FTXT: Blackwell Science http://www.blackwell-synergy.com/rd.asp?code=JEC&vol=89&page=528&goto=abstract
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Record 36 of 40 in GEOBASE 1997/12-2001/11

TI: Forest dynamics in flood plain forests in the Peruvian Amazon: Effects of disturbance and implications for management.
AU: Nebel-G.; Kvist-L.P.; Vanclay-J.K.; Vidaurre-H.
AD: G. Nebel, Department of Economics, Unit of Forestry, Royal Veterinary/Agricultural Univ., Rolighedsvej 23, 1958 Frederiksberg C, Denmark
EML: gne@kvl.dk
SO: Forest-Ecology-and-Management. 2001 SEP 01; 150(1-2): 79-92
PY: 2001
LA: English
LS: English
AB: Forest dynamics were studied from 1993 to 1997 for individuals _10 cm DBH in nine 1 ha permanent sample plots. They were established in natural flood plain forests located on the lower Ucayali river in the Peruvian Amazon. After inventories of three plots in each of three forest types, a light and a heavy felling treatment were applied to each of the two plots, while a third plot was kept untreated. Average annual stem mortality and recruitment rates in the untreated plots were among the highest observed in neotropical rain forests: mortality 2.2-3.2% per year, recruitment 3.0-4.6% per year. Dead individuals deviated significantly from random dispersion towards clumping. The average annual basal area growth was around 1 m2/ha per year, corresponding to average annual basal area growth rates of 3.5-3.8% per year in the untreated plots. No decrease in basal area growth was observed even in the treated plots where annual basal area mortality rates up to 41% during the first year were observed. The average diameter growth increased from 4.0-4.5 mm per year in the untreated plots to 5.3-6.8 mm per year in the treated plots. The stocking of commercial timber species was high with basal areas of 2.6-10.0 m2/ha and volumes of 59-240 m3/ha. The corresponding growth of basal area and volume of commercial timber species were also considerable, reaching values of 0.1-0.3 m2/ha per year and 2-9 m3/ha per year, respectively. These attributes suggested that forest management for timber production in these forests can be flexible and provide relatively high yields on a sustained basis. It appeared that management interventions can be carried out within the range of naturally occurring perturbations, although it should be noticed that only limited proportions of each habitat are disturbed at a time by nature. The patchy occurrence of habitats may provide logistic problems to management. < copyright > 2001 Elsevier Science B.V. All rights reserved.
IS: 0378-1127
CP: Netherlands
DE: Forestry
SC: ECOLOGICAL-ABSTRACTS: ECONOMIC-ECOLOGY (73-9-3)
KW: forest-dynamics; floodplain-forest; disturbance; growth; forest-management
GE: Peru-Amazon
PT: Journal; Article
RF: 62
AN: 2352219
UD: 200110
PI: S0378112700006824
CN: Copyright 2001 Elsevier Science Ltd. All rights reserved.
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Record 37 of 40 in GEOBASE 1997/12-2001/11

TI: Seasonality in ENSO-related precipitation, river discharges, soil moisture, and vegetation index in Colombia.
AU: Poveda-G.; Jaramillo-A.; Gil-M.M.; Quiceno-N.; Mantilla-R.I.
AD: M.M. Gil, Posgrado Aprovechamiento Recr. Hidr., Universidad Nacional de Colombian, Medelli, Colombia
SO: Water-Resources-Research. 2001; 37(8): 2169-2178
PY: 2001
LA: English
LS: English
AB: An analysis of hydrologic variability in Colombia shows different seasonal effects associated with El Nino/Southern Oscillation (ENSO) phenomenon. Spectral and cross-correlation analyses are developed between climatic indices of the tropical Pacific Ocean and the annual cycle of Colombia's hydrology: precipitation, river flows, soil moisture, and the Normalized Difference Vegetation Index (NDVI). Our findings indicate stronger anomalies during December-February and weaker during March-May. The effects of ENSO are stronger for streamflow than for precipitation, owing to concomitant effects on soil moisture and evapotranspiration. We studied time variability of 10-day average volumetric soil moisture, collected at the tropical Andes of central Colombia at depths of 20 and 40 cm, in coffee growing areas characterized by shading vegetation ("shaded coffee"), forest, and sunlit coffee. The annual and interannual variability of soil moisture are highly intertwined for the period 1997-1999, during strong El Nino and La Nina events. Soil moisture exhibited greater negative anomalies during 1997-1998 El Nino, being strongest during the two dry seasons that normally occur in central Colombia. Soil moisture deficits were more drastic at zones covered by sunlit coffee than at those covered by forest and shaded coffee. Soil moisture responds to wetter than normal precipitation conditions during La Nina 1998-1999, reaching maximum levels throughout that period. The probability density function of soil moisture records is highly skewed and exhibits different kinds of multimodality depending upon land cover type. NDVI exhibits strong negative anomalies throughout the year during El Ninos, in particular during September-November (year 0) and June-August (year 0). The strong negative relation between NDVI and El Nino has enormous implications for carbon, water, and energy budgets over the region, including the tropical Andes and Amazon River basin.
IS: 0043-1397
CP: United-States
DE: Climate-change
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-METEOROLOGY-AND-CLIMATOLOGY (71-7-13)
KW: seasonality; El-Nino-Southern-Oscillation; precipitation-assessment; river-discharge; soil-moisture; vegetation-index
GE: Colombia
PT: Journal; Article
RF: 31
AN: 2348007
UD: 200110
CN: Copyright 2001 Elsevier Science Ltd. All rights reserved.
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Record 38 of 40 in GEOBASE 1997/12-2001/11

TI: Hydrologic sensitivity of global rivers to climate change .
AU: Nijssen-B.; O'-Donnell-G.M.; Hamlet-A.F.; Lettenmaier-D.P.
AD: B. Nijssen, Department of Civil Engineering, Box 352700, University of Washington, Seattle, WA 98195-2700, United States
EML: nijssen@u.washington.edu
SO: Climatic-Change. 2001; 50(1-2): 143-175
PY: 2001
LA: English
LS: English
AB: Climate predictions from four state-of-the-art general circulation models (GCMs) were used to assess the hydrologic sensitivity to climate change of nine large, continental river basins (Amazon, Amur, Mackenzie, Mekong, Mississippi, Severnaya Dvina, Xi, Yellow, Yenisei). The four climate models (HCCPR-CM2, HCCPR-CM3, MPI-ECHAM4, and DOE-PCM3) all predicted transient climate response to changing greenhouse gas concentrations, and incorporated modern land surface parameterizations. Model-predicted monthly average precipitation and temperature changes were downscaled to the river basin level using model increments (transient minus control) to adjust for GCM bias. The variable infiltration capacity (VIC) macroscale hydrological model (MHM) was used to calculate the corresponding changes in hydrologic fluxes (especially streamflow and evapotranspiration) and moisture storages. Hydrologic model simulations were performed for decades centered on 2025 and 2045. In addition, a sensitivity study was performed in which temperature and precipitation were increased independently by 2< degrees >C and 10%, respectively, during each of four seasons. All GCMs predict a warming for all nine basins, with the greatest warming predicted to occur during the winter months in the highest latitudes. Precipitation generally increases, but the monthly precipitation signal varies more between the models than does temperature. The largest changes in the hydrological cycle are predicted for the snow-dominated basins of mid to higher latitudes. This results in part from the greater amount of warming predicted for these regions, but more importantly, because of the important role of snow in the water balance. Because the snow pack integrates the effects of climate change over a period of months, the largest changes occur in early to mid spring when snow melt occurs. The climate change responses are somewhat different for the coldest snow dominated basins than for those with more transitional snow regimes. In the coldest basins, the response to warming is an increase of the spring streamflow peak, whereas for the transitional basins spring runoff decreases. Instead, the transitional basins have large increases in winter streamflows. The hydrological response of most tropical and mid-latitude basins to the warmer and somewhat wetter conditions predicted by the GCMs is a reduction in annual streamflow, although again, considerable disagreement exists among the different GCMs. In contrast, for the high-latitude basins increases in annual flow volume are predicted in most cases.
IS: 0165-0009
CP: Netherlands
DE: Climate-change
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-METEOROLOGY-AND-CLIMATOLOGY (71-7-13)
KW: hydrological-response; climate-change; general-circulation-model; sensitivity-analysis; precipitation-assessment; river-flow
PT: Journal; Article
RF: 71
AN: 2346255
UD: 200110
CN: Copyright 2001 Elsevier Science Ltd. All rights reserved.
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Record 39 of 40 in GEOBASE 1997/12-2001/11

TI: Is the Negro River Basin (Amazon) impacted by naturally occurring mercury?
AU: Fadini-P.S.; Jardim-W.F.
AD: W.F. Jardim, Instituto de Quimica, Universidade Estadual de Campinas, Caixa Postal 6154, CEP 13083-970 Campinas, Brazil
EML: wfjardim@iqm.unicamp.br
SO: Science-of-the-Total-Environment. 2001 JUL 25; 275(1-3): 71-82
PY: 2001
LA: English
LS: English
AB: In order to investigate the major sources and cycling of mercury in the Negro River Basin (Amazon), total metal measurements were carried out in soils, in river and lake waters, in the atmosphere, and in bulk precipitation during the period 1995 throughout 1998. Median values of 1.3 ng m-3 in the atmosphere, 172 < mu >g kg-1 in soils, 4.6-7.5 ng l-1 in three different lakes, 4.5 ng l-1 in 17 different Negro River tributaries and 20.3 < mu >g m-2 year-1 in bulk precipitation were found. Mercury concentrations in rivers and lakes waters, as well as in soils and bulk precipitation were high, considering the scarcity of anthropogenic point sources in the region. Mercury leaching from soil, the largest regional reservoir of this metal, was considered to be the major pathway to mercury enrichment in the region. Copyright < copyright > 2001 Elsevier Science B.V.
IS: 0048-9697
CP: Netherlands
DE: Pollution
SC: GEOGRAPHICAL-ABSTRACTS: PHYSICAL-GEOGRAPHY-SYNOPTIC-GEOGRAPHY (71-1-2)
KW: mercury-element-; river-basin; pollution-monitoring
GE: Brazil-Amazonas-Negro-Baisn
PT: Journal; Article
RF: 63
AN: 2343682
UD: 200110
PI: S004896970000855X
CN: Copyright 2001 Elsevier Science Ltd. All rights reserved.
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Record 40 of 40 in GEOBASE 1997/12-2001/11

TI: Introduction: The Brazilian Atlantic Forest.
AU: Morellato-L.P.C.; Haddad-C.F.B.
AD: L.P.C. Morellato, Departamento de Botanica, Plant Phenol./Seed Disper. Res. Grp., Universidade Estadual Paulista, 13506-900 Rio Claro, Sao Paulo, Brazil
SO: Biotropica. 2001; 32(4 B): 786-792
PY: 2001
LA: English
LS: English; Portuguese
AB: The year 2000 marks 500 years of massive destruction for the Brazilian Atlantic Forest, as a consequence of the European colonization of Brazil. Today, the Atlantic Forest is restricted to ca 98,800 km<inf>2</inf> of remnants, or 7.6 percent of its original extension. The Atlantic Forest continues to suffer under severe anthropogenic pressure, risking imminent extinction of the remaining species. Our current knowledge indicates that this complex biome contains a species diversity higher than most of the Amazon forests, and also has high levels of endemism. The 13 selected articles in this special issue present data on the natural history, ecology, sustainable management, and conservation of the Atlantic Forest. These articles represent a sample of the research conducted to date in the region and suggest avenues of future research, particularly with regard to conservation alternatives for the remaining portions of the Atlantic Forest. This special issue represents one of the first general references pertaining to the Brazilian Atlantic Forest.
IS: 0006-3606
CP: United-States
DE: Plant-ecology:-general
SC: ECOLOGICAL-ABSTRACTS: TERRESTRIAL-ECOLOGY (73-4-6-1)
KW: forest-ecosystem; species-diversity; endemism; deforestation
GE: Brazil
PT: Journal; Article
RF: 25
AN: 2334279
UD: 200107
CN: Copyright 2001 Elsevier Science Ltd. All rights reserved.
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