Record Details
Air-sea heat exchange along the northern sea surface temperature front in the eastern tropical Pacific
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Air-sea heat exchange along the northern sea surface temperature front in the eastern tropical Pacific |
| Names |
Thum, Nicolai
(creator) Esbensen, Steven K. (advisor) |
| Date Issued | 2001-02-22 (iso8601) |
| Note | Graduation date: 2001 |
| Abstract | The atmospheric response to the oceanic forcing in the eastern Pacific along the northern equatorial sea surface temperature (SST) front is investigated in terms of sensible and latent heat flux during the 6-month period 28 July 1999 through 27 January 2000. Of particular interest is the atmospheric boundary layer (ABL) response to oceanic Tropical Instability Waves (TIWs) that distort the SST front during May through January in normal years. In previous studies, time series of boundary layer properties clearly show the influence of TIWs but the relationship to spatial patterns of SST and wind stress has been inferred only from sparse in situ data. In this study, satellite observations are used to composite in situ data from moorings to compensate for the lack of a spatially dense mooring array. The variability in the position of the SST front caused by propagating TIWs enables fixed mooring locations to measure the atmospheric boundary layer (ABL) response from a large range of locations relative to the front. The satellite data enable determination of the precise location of the mooring relative to the front. The advantage of this strategy is the recurring measurement of the ABL response to the SST front over the six month period considered here. The results indicate that the TIW-induced perturbations of sensible and latent heat flux are spatially shifted in phase towards the east relative to the perturbations of SST. The maximum fluxes are not centered directly over the warmest water, but are shifted towards the portion of the frontal region where a disequilibrium boundary layer is expected due to the advection of colder air from the equatorial region. The changes of sensible and latent heat fluxes across the SST front have magnitudes of about 11 Wm⁻² and 126 Wm⁻², respectively. The sensible and latent heat flux patterns are interpreted in two complementary ways: (1) as an atmospheric response to the change of oceanic forcing as air flows across the SST front; and (2) as the atmospheric response to westward propagating TIWs along the SST front. |
| Genre | Thesis/Dissertation |
| Topic | Ocean-atmosphere interaction -- South Pacific Ocean |
| Identifier | http://hdl.handle.net/1957/28703 |
