FSU-GSM forecast error sensitivity to initial conditions: Application to Indian summer monsoon

The full-physics adjoint of the FSU Global Spectral Model of version T42L12 is applied to carry out sensitivity analysis of the localized model foreca st error to the initial conditions for a case test occurring on June 8, 198 8 during the Indian summer monsoon. The results show that adjoint sensitivi ty based on ECMWF analysis can be used to identify regions with large analy sis uncertainties. The conclusion is that more observations are required ov er the northern Bay of Bengal to improve the quality of analyses so as to a meliorate the model forecast skill.