BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20250512T102047EDT-1470OIX4Ja@132.216.98.100 DTSTAMP:20250512T142047Z DESCRIPTION:Atmospheric and Oceanic Sciences Departmental Seminar Series\n \npresents\n\nWhy does climate sensitivity go up as ocean heat uptake decl ines? A linear systems perspective\n\na talk by\n Brian Rose\n Assistant Pro fessor\, Atmospheric and Environmental Sciences\, University of Albany\, S tate University of New York\, New York\n\nTransient climate sensitivity te nds to increase on multiple timescales in climate models subject to an abr upt CO2 increase\, which suggests that (1) we may be systematically undere stimating equilibrium sensitivity in the models\, and (2) constraining equ ilibrium sensitivity from observations is a tricky business at best. I wil l argue that the radiative feedback and ocean heat uptake processes govern ing transient sensitivity are intimately and physically connected. Idealiz ed GCM experiments show that the global climatic impact of spatially local ized ocean heat uptake patterns are very sensitive to their geographical d istribution. I will discuss these results in terms of the efficacy concept and a linear systems perspective in which responses to individual climate forcing agents are additive. Heat uptake can be treated as a slowly varyi ng forcing on the atmosphere and surface\, whose efficacy is strongly dete rmined by its spatial pattern. An illustrative linear model demonstrates t he emergence of increasing climate sensitivity as a simple consequence of the slow decay of high-efficacy sub-polar heat uptake. Shortwave cloud fee dbacks are a key player in this increasing climate sensitivity\, both in i dealized and comprehensive models. I propose a causal physical mechanism l inking sub-polar heat uptake to a global-scale increase in lower-troposphe ric stability.\n\nMonday Sep 23/ 3:30 PM/ Burnside Hall/ Room 934\n DTSTART:20190923T193000Z DTEND:20190923T210000Z LOCATION:Room 934 SUMMARY:Why does climate sensitivity go up as ocean heat uptake declines? A linear systems perspective URL:/meteo/channels/event/why-does-climate-sensitivity -go-ocean-heat-uptake-declines-linear-systems-perspective-300718 END:VEVENT END:VCALENDAR