Pattern scaling technique will play an essential role in AR5. The basic assumption of the pattern scaling is that spatial response pattern per one degree increase in the global mean surface air temperature is common between emission scenarios. In this study, we investigated the dependencies of scaling pattern of annual mean surface air temperature on RCPs emission scenarios. Dependency of scaling pattern on emission scenario is shown to be large in mid-latitude and high-latitude of the Northern hemisphere. The difference of pattern scaling over northern hemisphere mid-latitude are induced by the differences in sulfate aerosol emission, and that over high latitude of the Northern hemisphere are mainly induced by the nonlinear response of sea ice and ocean heat uptake to global warming.

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