Speaker: David Battisti, Professor of Atmospheric and Climate Science, University of Washington
The leading pattern of year-to-year variability in summertime (JJA) temperature in the western US spans the entire domain and explains over half the total variance in temperature and in total forest area burned in the western US. In observations, this pattern is linked to springtime (MAM) soil moisture anomalies in the southwest (SW) US that are, in turn, linked to wintertime (DJF) precipitation anomalies; as an example, negative precipitation anomalies in DJF are followed by soil moisture deficits in MAM the SW US that give rise to warmer-than-normal JJA temperatures throughout the western US. Climate models (with and without interactive oceans) reproduce the observed relationships. We present new experiments that show the variance in summertime temperature throughout the western US is causally linked to preceding springtime soil moisture anomalies in the southwest US and that illuminate aspects of the underlying physics.
**The CPEP Seminar Series is partnering with the AOS Colloquium Series on this lecture. Please note the different than usual date, time, and location**