Simulating Multi-Season Past Droughts
Abstract

Abstract Author: Sumant Nigam

Abstract Title: North American Droughts in the 20th Century: Role of SST Variability and Trend

Abstract:

• Models are improving but still challenged in simulating the regional-to-subcontinental scale hydroclimate anomalies, especially in summer
• Insights into regional climate projections can, perhaps, be obtained in the interim by mining the observational record itself
• An evolution-centric analysis of Pacific SSTs (and residual Atlantic SSTs) leads to characterization of the secular trend in context of natural low-frequency variability. The clarified struture of decadal variability and the non-stationary secular trend result in an unprecedented reconstruction of summer/fall droughts and wet periods from the concurrent SST anomalies.
• To be insightful, empirical drought reconstruction will need grounding in mechanisms. Findings from ongoing analysis will be reported.
• Observational analysis indicates an important role for the Atlantic basin SSTs (both tropical and extratropical) in North American summer/fall droughts.