Evidence for Enhanced Land–Atmosphere Feedback in a Warming Climate

• DOI: 10.1175/jhm-d-11-0104.1
• Publication Date: 2012-06-27T21:41:52Z
• Authors: Paul A. Dirmeyer; Benjamin A. Cash; James L. Kinter; Cristiana Stan; Thomas Jung; Lawrence Marx; Peter Towers; Nils Wedi; Jennifer M. Adams; Eric L. Altshuler; Bohua Huang; Emilia K. Jin; Julia Manganello
• Keywords: Water cycle

Abstract Global simulations have been conducted with the European Centre for Medium-Range Weather Forecasts operational model run at T1279 resolution multiple decades representing climate from late twentieth and twenty-first centuries. Changes in key components of water cycle are examined, focusing on variations short time scales. Metrics coupling feedbacks between soil moisture surface fluxes properties planetary boundary layer (PBL) inspected. Features precipitation other trends coupled consensus projections well simulated. Extreme 6-hourly rainfall totals become more intense over much globe, suggesting an increased risk flash floods. Seasonal-scale droughts projected to escalate subtropics midlatitudes during summer, while tropical winter less likely. These changes accompanied by increase responsiveness evapotranspiration variations. Even though daytime PBL depths most locations next century, greater latent heat also occur land areas, contributing a larger energy effect per unit mass air, except some semiarid regions. This general land–atmosphere is represented combined metric as “land index” that incorporates terrestrial atmospheric effects together. The enhanced consistent changes, but causal connection cannot be made without further sensitivity studies. Nevertheless, this approach could applied output traditional change assess feedbacks.