Jonathan Karr
Hydrology
of altered tropical forest
Notes
- Forest
- High rates
of evapotranspiration
- High rate of
water infliltration into soil, high values of saturated hydraulic conductivity
(Ks)
- 25-56% of rainfall
due to recycling of water evaporated with in basin (Eltahir EAB, Bras
RL. 1996. Precipitation recycling. Reviews of
Geophysics 34: 367–378
- Deforestation
- Lowers rate
of evapotranspiration
- Causes streamflow
to increase
- May cause
increased flood frequency
- Lowers Ks value
due to compaction of soil by humans, animals, vehicals
- Replacement
of entire Amazon Basin with pasture could result in 20% decrease in rainfall.
- Regional evapotranspiration
may be greater in an area composed of small patches
- Regrowth
- Ks values increase
with time
References to Pursue
- Circulation Model
- Nobre CA, Sellers
PJ, Shukla J. 1991. Amazonian deforestation and regional climate change.
Journal of Climate 4: 957–988.
- Polcher J,
Laval K. 1994. The impact of African and Amazonian deforestation on tropical
climate. Journal of Hydrology 155: 389–405.
- McGuffie K,
Henderson-Sellers A, Zhang H, Durbridge TB, Pitman AJ. 1995. Global sensitivity
to tropical deforestation. Global and Planetary Change 10: 97–128.
- Henderson-Sellers
A, Zhang H, Howe W. 1996. Human and physical aspects of tropical deforestation.
In Climate Change: Developing Southern Hemisphere Perspectives, Giambelluca
TW, Henderson-Sellers A (eds). John Wiley and Sons: Chichester, UK.
- Xue Y, Bastable
HG, Dirmeyer PA, Seller PJ. 1996. Sensitivity of simulated surface fluxes
to changes in land surface parameterizations—a study using ABRACOS data.
Journal of Applied Meteorology 35: 386–400.
Diurnal Variability of Tropical Rainfall Retrieved from Combined
GOES and TRMM Satellite Information
Notes
- Diurnal rainfall
measurement is made possible through the Tropical Rainfall Measuring Mission
(TRMM) Microwave Imager (TMI) and precipitation radar (PR) instruments
- When precipitation
occurs regularly during particular time periods of the day the atmospheric
system usually is characterized by conditions and physical processes that
suggest strong convection during the favored periods
- Infared (PR)
- High frequency
of monitoring
- Use only information
of cloud-top temperature to determine surface rainfall
- Microwave (TMI)
- Based on the
distribution of hyrdrometeors within the cloud
- Explain instantaneous
rainfalls more realistically, but can only monitor twice / day for any location
- Housed on low-orbiting
satellites
References to
Pursue
- Algorithm (Precipitation
Estimation from Remotely Sensed Information using Artificial Neural Networks
(PERSIANN) system) used to estimate rainfall
- Hsu, K., X.
Gao, S. Sorooshian, and H. V. Gupta, 1997: Precipitation estimation from remotely
sensed information using artificial neural networks. J. Appl. Meteor., 36,
1176–1190.
- Sorooshian,
S., K. Hsu, X. Gao, H. V. Gupta, B. Imam, and D. Braithwaite, 2000: Evaluation
of PERSIANN system satellite-based estimates of tropical rainfall. Bull.
Amer. Meteor. Soc., 81, 2035–2046.