Evidence for Local and Nonlocal Barotropic Responses to Atmospheric Forcing during Bempex
نویسندگان
چکیده
The coherence between single bottom pressure .4 barotropic velocity records collected in the North •c during BEM• and air pressure, wind stress, and wind stress cuff derived from FNOC products are examined •ov• the 2-'00-1 day period band. Strong coherence between the bottom pressure and all atmospheric variables is seen, with nonlocal coherence (maximum up to 1000 km to the southeast) dominating at periods longer than =!0 d and local coherence being prevalent at shorter periods, consistent with predictions from existing models of •mospherically-forced barotropic motion. The azimuth of be .nonlocal coherence maximum relative to the ocean stafirm is a function of frequency, which is not expected from the models. The coherence between the barotropic velocity (as measured by the electric field) and the atmospheric variables is weaker, but nonlocal coherence with the wind stress and wind stress curl at periods greater than a week, .aM local coherence with the wind stress at shorter periods, •is statis.•cally significant.
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