Empirical Orthogonal Function Analysis of Observed and Modeled Solar Spectral Irradiance

Guoyong Wen [wen@climate.gsfc.nasa.gov], Goddard Earth Sciences and Technology Center (GEST) and NASA/Goddard Space Flight Center;Robert F. Cahalan, NASA/Goddard Space Flight Center; and Juan Fontenla, University of Colorado, Boulder.

Empirical orthogonal function (EOF) analysis is a useful method for statistical analysis of large data sets. The EOF analysis has been widely used in meteorology and climate research. This paper demonstrates that this is a powerful tool for analyzing solar spectral irradiance (SSI) and a method to test our understanding of variations in SSI. We will compare EOF components from time series of daily observed SSI from the SORCE Spectral Irradiance Monitor (SIM) preliminary data and that from the SRPM model (Solar Radiation Physical Modeling). Agreement of EOFs may indicate the validity of the model, while the disagreement in major EOF components may indicate limitations of the model or potential problems in instrument degradation