Lake Records of Hydroclimate Variability in the Southeastern United States from the Middle Holocene to Present-Day
Abstract
The Southeastern United States is an important agricultural region, but recent flooding and drought events have caused billions of dollars in economic losses. There is a decided lack of understanding regarding the drivers of hydroclimate variability in this region in part because there are fewer paleoclimate records. We present here data from two lakes in southeastern Alabama and Georgia and aim to characterize changes in lake level and vegetations response to changing climatic conditions over the last several millennia. Preliminary data, including physical, biological, and geochemical proxies, suggest that pronounced increases in effective moisture occurred in the middle Holocene and Little Ice Age, in general agreement with a few previous studies from several decades ago and more recently. We suggest that shifts in the mean state of the Pacific North American (PNA) pattern have played an important role in influencing rainout from Gulf moisture sources. If our hypothesis is correct, we expect to see a precipitation dipole with lakes in the northeast parts of Alabama and Georgia, which future work will investigate. Future work will also include the collection of transect cores to further quantify lake levels.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2021
- Bibcode:
- 2021AGUFMPP25E0976H