The paleo record permits study of the climate system in widely
varying conditions, providing constraints on climate variability and
the potential range of climate states. For example, the
glacial-interglacial cycles of the last 400,000 years show a highly
regular, repeating pattern of high CO2 during warm periods
(interglacials) and low CO2 during cold periods (glacials). The
most recent of the glacial periods, the Last Glacial Maximum (LGM),
occurred about 20,000 years ago. Well-constrained aspects
of the LGM climate include atmospheric CO2 levels about 90 ppm lower
than pre-industrial levels, large ice sheets across northern N.
America
and N. Europe, and sea-level about 120 m lower than today's.
Although less well-constrained, several other changes in key climate
characteristics have been proposed. In the Atlantic
basin, these include an increase in zonal and meridional sea surface
temperature gradients, changes in the westerly winds, and a shift in
deep ocean water mass distributions.
I am studying the extent to which these and other proposed changes
are consistent with (1) a range of observational evidence and (2)
known oceanic physics. To do this, I have built an LGM Atlantic
Ocean state estimate -- a synthesis of observational records and a
numerical model of ocean circulation. This approach also permits
quantitative study of uncertainties and potential biases in the
model and data.
Invited seminars related to this work:
- H. Dail, University of Rhode Island GSO Physical Oceanography
Seminar, May 2011
A model/data synthesis of the Last Glacial
Maximum Atlantic: SSTs and wind field changes
- H. Dail, Harvard University ClimaTea, April 2011
Synthesizing proxy records and an ocean circulation
model to characterize the Last Glacial Maximum
- H. Dail, WHOI Paleo Lunch Seminar, November 2010
N. Atlantic circulation at the LGM: what can we
learn by synthesizing ocean dynamics and proxy records?
Recent contributed presentations:
- Graduate Climate Conference, Woods Hole, MA, Oct. 2011
- Patullo Conference, Airlie Center, VA, Oct. 2011
- Advanced Climate Dynamics Courses: Dynamics of Past
Warm Climates, Friday Harbor Labs, WA, Sep. 2011
- Atmosphere and Ocean Science Days, MIT, June 2011
- ECCO2 Meeting, MIT, May 2011
- European Geosciences Union (EGU), Vienna, April 2011
[abstract,
poster]
- International Conference on Paleoceanography (ICP),
San Diego, Sep. 2010
[abstract]
- European Geosciences Union (EGU), Vienna, May 2010
[abstract,
presentation]
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