Record Details
Large-scale response to atmospheric forcing of shelf currents and coastal sea level off the west coast of North America : May-July 1981 and 1982
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Large-scale response to atmospheric forcing of shelf currents and coastal sea level off the west coast of North America : May-July 1981 and 1982 |
| Names |
Denbo, D. W.
(creator) Allen, John S. (creator) |
| Date Issued | 1987-02-15 (iso8601) |
| Note | copyrighted by American Geophysical Union |
| Abstract | The response of alongshore currents V over the continental shelf and of coastal sea level ζ along the Pacific coast of North America to atmospheric forcing on large alongshore scales (100-2000 km) during May-July 1981 (Coastal Ocean Dynamics Experiment (CODE) 1) and May-July 1982 (CODE 2) has been studied using sea level and wind measurements from coastal stations and buoys between 33°N and 48°N and using current measurements from five locations between 35°N and 48°N. Characteristics of the large scale response of V and ζ to fluctuations in the alongshore component of the wind stress t varied with latitude and with year in relation to variations in τ. In 1981, large-scale fluctuations were coherent within, but not between, separate domains north and south of 42°N. In 1982, large-scale coherent fluctuations were found only in a northern domain that extended much farther south to near 37°N. Accordingly, in 1981, alongshore current V fluctuations from 39°N (CODE) were coherent with V from 35°N, while in 1982, V fluctuations from 39°N were coherent with those north to 48°N. In 1981 the northern domain fluctuations were forced by r between 42°N and 45°N with southern domain forcing at 35°-36°N. In 1982, northern domain fluctuations were forced by τ over a region of much larger alongshore extent (37°-48°N). High values of space-lagged coherences between V and τ(y) (y is the alongshore coordinate) indicate that V at 39°N was strongly wind driven. Maximum squared coherences of V versus τ(y) are found with to the south by 100-300 km for low frequencies (w ≤ 0.23 cpd in 1981, w ≤ 0.14 cpd in 1982) and with r from near-local stations at higher w, indicating the importance of remote forcing at low frequencies and local forcing at high frequencies. The response of V to τ(y) at 35°N and 43°N was more complicated, but evidence for strong wind forcing is found in several frequency bands for V at 43°N during 1981 and 1982 and at 35°N during 1981. At 48°N, V was forced in 1982 for w ≤ 0.18 cpd by τ from locations 300-1400 km to the south. |
| Genre | Article |
| Identifier | Allen, J. S., Denbo, D. W. (1987) Large-scale response to atmospheric forcing of shelf currents and coastal sea level off the west coast of North America : May-July 1981 and 1982. J. Geophys. Res., 92, C2, 1757-1782. |
