Midlatitude Eddies, Storm-Track Diffusivity, and Poleward Moisture Transport in Warm Climates
2012 (English)In: Journal of Atmospheric Sciences, ISSN 0022-4928, E-ISSN 1520-0469, Vol. 69, no 11, 3237-3250 p.Article in journal (Refereed) Published
Recent work using both simplified and comprehensive GCMs has shown that poleward moisture transport across midlatitudes follows Clausius-Clapeyron scaling at temperatures close to modern, but that it reaches a maximum at sufficiently elevated temperatures and then decreases with further warming. This study explores the reasons for this nonmonotonic behavior using a sequence of NCAR Community Atmosphere Model, version 3 (CAM3) simulations in an aquaplanet configuration spanning a broad range of climates. No significant change is found in the scale, structure, or organization of midlatitude eddies across these simulations. Instead, the high-temperature decrease in poleward moisture transport is attributed to the combined effect of decreasing eddy velocities and contracting mixing lengths. The contraction in mixing length is, in turn, a consequence of the decreasing eddy velocities in combination with constant eddy decorrelation time scales.
Place, publisher, year, edition, pages
2012. Vol. 69, no 11, 3237-3250 p.
Meteorology and Atmospheric Sciences
IdentifiersURN: urn:nbn:se:su:diva-83030DOI: 10.1175/JAS-D-12-035.1ISI: 000310652500008OAI: oai:DiVA.org:su-83030DiVA: diva2:574401