Abstract
AbstractOcean‐atmosphere interactions play a key role in climate variability on a wide range of timescales from seasonal to decadal and longer. The extratropical oceans are thought to exert noticeable feedbacks on the atmosphere especially on decadal and longer timescales, yet the large‐scale atmospheric response to anomalous extratropical sea surface temperature (SST) is still under debate. Here we show, by means of dedicated high‐resolution atmospheric model experiments, that sufficient daily variability in the extratropical background SST needs to be resolved to force a statistically significant large‐scale atmospheric response to decadal North Pacific SST anomalies associated with the Pacific Decadal Oscillation, which is consistent with observations. The large‐scale response is mediated by atmospheric eddies. This implies that daily extratropical SST fluctuations must be simulated by the ocean components and resolved by the atmospheric components of global climate models to enable realistic simulation of decadal North Pacific sector climate variability.
Highlights
The North Pacific exhibits sea surface temperature (SST) variability on a variety of timescales
By means of dedicated high-resolution atmospheric model experiments, that sufficient daily variability in the extratropical background SST needs to be resolved to force a statistically significant large-scale atmospheric response to decadal North Pacific SST anomalies associated with the Pacific Decadal Oscillation, which is consistent with observations
In order to investigate the dynamics of the atmospheric response to North Pacific SST variability, the European Centre/Hamburg version 5 atmospheric general circulation model [Roeckner et al, 2003] was integrated on a T213 grid with 31 levels up to 10 hPa
Summary
The North Pacific exhibits sea surface temperature (SST) variability on a variety of timescales. Atmospheric forcing and a number of oceanic processes such as the reemergence mechanism [Alexander et al, 1999] have been proposed as influences on the North Pacific SST. Independent of their origin, changes in SST alter the lower boundary condition for the atmosphere and have the potential to drive large-scale atmospheric circulation changes [Czaja and Frankignoul, 1999, 2002; Rodwell and Folland, 2002].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
