Molecules are forever… and in their structural formulae, they record environmental conditions: temperature, precipitation, nutrient availability, pH. My lab's research focuses on how we can use molecules preserved in sedimentary archives - lake and ocean cores - to learn about past climate change. Why study past climate change (paleoclimate)? Just as history informs us about human behavior, paleoclimate informs us about the nature of climate change on Earth. In doing so, it also helps the climate community predict the effects of anthropogenic global warming. All this, from tiny bits of fat.
[5/20/13] Our paper comparing proxy hydroclimate data and climate model simulations during the Last Glacial Maximum is out today in Nature Geoscience. Read the WHOI press release and check out the article online at Nature Geoscience (requires library access). If you would like a reprint please contact me directly.
Pedro N. DiNezio & Jessica E. Tierney, Nature Geoscience
During the Last Glacial Maximum, temperatures within the warm pool were cooler than today and precipitation patterns were altered, but the mechanism responsible for these shifts remains unclear. Here we use a synthesis of proxy reconstructions of warm pool hydrology and a multi-model ensemble of climate simulations to assess the drivers of these changes. Only one model out of twelve simulates a pattern of hydroclimate change similar to our reconstructions, as measured by the Cohen’s κ statistic. Exposure of the Sunda Shelf by lower glacial sea level plays a key role in the hydrologic pattern simulated by this model, which results from changes in the Walker circulation driven by weakened convection over the warm pool. We therefore conclude that on glacial–interglacial timescales, the growth and decay of ice sheets exert a first-order influence on tropical climate through the associated changes in global sea level.