Publication Date:
2022-10-26
Description:
© The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Munoz, S. E., Porter, T. J., Bakkelund, A., Nusbaumer, J., Dee, S. G., Hamilton, B., Giosan, L., & Tierney, J. E. Lipid biomarker record documents hydroclimatic variability of the Mississippi River Basin during the common era. Geophysical Research Letters, 47(12), (2020): e2020GL087237, doi:10.1029/2020GL087237.
Description:
Floods and droughts in the Mississippi River basin are perennial hazards that cause severe economic disruption. Here we develop and analyze a new lipid biomarker record from Horseshoe Lake (Illinois, USA) to evaluate the climatic conditions associated with hydroclimatic extremes that occurred in this region over the last 1,800 years. We present geochemical proxy evidence of temperature and moisture variability using branched glycerol dialkyl glycerol tetraethers (brGDGTs) and plant leaf wax hydrogen isotopic composition (δ2Hwax) and use isotope‐enabled coupled model simulations to diagnose the controls on these proxies. Our data show pronounced warming during the Medieval era (CE 1000–1,600) that corresponds to midcontinental megadroughts. Severe floods on the upper Mississippi River basin also occurred during the Medieval era and correspond to periods of enhanced warm‐season moisture. Our findings imply that projected increases in temperature and warm‐season precipitation could enhance both drought and flood hazards in this economically vital region.
Description:
This project was supported by grants to S. E. M and L. G. (NSF EAR‐1804107), T. J. P. (NSERC Discovery Grant), and S. G. D. (NOAA‐NA18OAR4310427).
Keywords:
Lipid biomarker
;
Leaf wax
;
BrGDGT
;
Common Era
;
Paleoclimate
;
Hydroclimate
Repository Name:
Woods Hole Open Access Server
Type:
Article
Permalink
