Assessing Atmospheric Response to Surface Forcing in the Observations. Part II: Cross Validation of Seasonal Response Using GEFA and LIM

Abstract

he authors compared the assessment of the seasonal cycle of the atmospheric response to surface forcing in three statistical methods, generalized equilibrium feedback analysis (GEFA), linear inverse modeling (LIM), and fluctuation?dissipation theorem (FDT). These methods are applied to both a conceptual climate model and the observation. It is found that LIM and GEFA are able to reproduce the major features of the seasonal response consistently, whereas FDT tends to generate a bias of the phase of the seasonal cycle. The success of LIM and GEFA for the assessment of the seasonal response is due to the slowly varying nature of the annual cycle relative to the atmospheric response time. Therefore, the authors recommend GEFA and LIM as two independent methods for the assessment of the seasonal atmospheric response in the observation.