Unforced Surface Air Temperature Variability and Its Contrasting Relationship with the Anomalous TOA Energy Flux at Local and Global Spatial Scales

Unforced global mean surface air temperature ((T) over bar) is stable in the long term primarily because warm T anomalies are associated with enhanced outgoing longwave radiation (up arrow LW) to space and thus a negative net radiative energy flux ((N) over bar, positive downward) at the top of the atmosphere (TOA). However, it is shown here that, with the exception of high latitudinal and specific continental regions, warm unforced surface air temperature anomalies at the local spatial scale [T(theta, phi), where (theta, phi) = (latitude, longitude)] tend to be associated with anomalously positive N(theta, phi). It is revealed that this occurs mainly because warm T(theta, phi) anomalies are accompanied by anomalously low surface albedo near sea icemargins and over high altitudes, low cloud albedo overmuch of themiddle and lowlatitudes, and a largewater vapor greenhouse effect over the deep Indo- Pacific. It is shown here that the negative (N) over bar versus (T) over bar relationship arises because warm (T) over bar anomalies are associated with large divergence of atmospheric energy transport over the tropical Pacific [where theN(theta, phi) versus T(theta, phi) relationship tends to be positive] and convergence of atmospheric energy transport at high latitudes [where the N(theta, phi) versus T(theta, phi) relationship tends to be negative]. Additionally, the characteristic surface temperature pattern contains anomalously cool regions where a positive local N(theta, phi) versus T(theta, phi) relationship helps induce negative (N) over bar. Finally, large- scale atmospheric circulation changes play a critical role in the production of the negative (N) over bar versus (T) over bar relationship as they drive cloud reduction and atmospheric drying over large portions of the tropics and subtropics, which allows for greatly enhanced up arrow LW.