Paleoclimate synthesis research

Farm in Monument Valley, AZ, on the Navajo Nation. Photo by J. Cole.

Some of the most interesting questions in paleoclimate research involve syntheses or comparisons among published datasets. I am actively involved in such work along two fronts:

Understanding drivers of drought in the western US: I've worked with Ed Cook and Jonathan Overpeck to describe how ENSO variability relates to SW drought in tree-ring records. Building on these results (piblished in GRL in 1998 and 2002), we are expanding our approach to develop a synthesis of drought in the Holocene using multiple proxy records across the region. We are collaborating with Bette Otto-Bliesner at NCAR to explore how drought is represented in global climate models and whether the statistics of past droughts can be captured by paleoclimate model simulations. We will use paleo model runs from Holocene intervals to explore potential mechanisms of drought initiation and persistence as seen in the paleo data, and to assess how well models reproduce past observed conditions. Finally, we will produce a public, well-documented database of drought records useful for a wide range of drought-related analysis. This work is the doctoral research of Toby Ault and is funded by NOAA's CCDD program and an NSF doctoral fellowship. Undergraduate Alena Kimbrough is also contributing, supported by a Mellon fellowship.

Aerial view of Nonouti Atoll, Kiribati, Central Pacific. With maximum elevation <5m, Kiribati is threatened by the rising seas that accompany global warming. Photo by A. Tudhope.