FY 2000

Validating the NSCAT winds in the vicinity of the Pacific Intertropical Convergence Zone

Yu, Z., and D.W. Moore

Geophys. Res. Lett., 27(14), 2121–2124, doi: 10.1029/1999GL011250 (2000)

It is known that the NSCAT winds are influenced by precipitation, and so are potentially in error in regions of high rainfall, such as the Pacific ITCZ. We assess this potential error by comparing NSCAT winds to other products and by determining the possible impact on modeling the Pacific NECC. In the latitude band of the ITCZ, there are large differences between wind products from the ECMWF and NSCAT. A comparison with TAO buoy winds shows a bias of NSCAT data towards a higher zonal wind stress at 8°N. The spatial distribution of this bias distorts the Ekman pumping velocity across the ITCZ, and results in a NECC that is 0.1-0.2 m/s weaker than that forced by the ECMWF winds. This is not a trivial amount during the spring, when the strength of the NECC in the eastern Pacific is of the same magnitude.