The severe drought in 2010-2011 across the Horn of Africa caused widespread famine and a humanitarian crisis. Such events remind us of how vulnerable this region is to climate variability. Though we know that El Niño can affect precipitation in this region, very little is known about long-term (decadal and longer) trends, making future prediction of drought and food security challenging. With support from the National Science Foundation, we are developing the first paleoclimate record of drought in the Horn of Africa region, based on hydrogen isotopes measured on terrestrial leaf waxes. We will also reconstruct local SSTs in the Gulf of Aden, and use climate model simulations to understand the influence that the Indian and Pacific Oceans may have on decadal-scale precipitation.

Multidecadal variability in East African hydroclimate controlled by the Indian Ocean
Jessica E. Tierney, Jason E. Smerdon, Kevin J. Anchukaitis and Richard Seager Nature, 493, 389-392.
Multidecadal variability in East African rainfall is an important but poorly understood component of the climate of the region. Here we use paleoclimate records of relative moisture balance from the last millennium and general circulation model simulations to provide perspective on multidecadal variability in East Africa and insight on the mechanisms that drive it.