SUMMARY OF COAST FLIGHT 4

Date: Fri, 25 May 2001 14:06:59 -0400
From: JOHN M BANE
To: coast@OCE.ORST.EDU
Subject: COAST Flight Report- May 24

COAST Flight Number 4 was conducted on May 24, 2001. The flight covered the Big Box, with lines 8 through 1 being flown from south to north. Measurements were made of: SST, ocean color, and ocean subsurface temperature; atmospheric winds, temperature and humidity. We saw the R/V Thompson near the inshore end of Line 2 and the R/V Wecoma nearshore, just south of Newport.

AXBTs were deployed on four lines: 2, 4, 6 and 8. A data return of 100% was obtained with the AXBTs. Deployments were as follows:
Line 2: 6 AXBTs
Line 4: 6 AXBTs
Line 6: 7 AXBTs
Line 7: 5 AXBTs

SST profiles showed a strong temperature front located near the 50m isobath from about Line 2 southward to at least Newport. Very cold water inshore of the front was apparent, but our shallowest AXBT drops are made on the 50m contour, so no subsurface temperature data were gained from this flight in the coldest water.

To obtain data for vertical sections of the atmospheric variables, we flew a two-cycle "sawtooth" pattern (climb from 60m altitude to 800m altitude, descent to 60m, then again to 800m, then finally to 60m) along each of Lines 1, 3, 5 and 7. The offshore extent of each pattern was just west of 125W. A moderate atmospheric temperature inversion was seen at all locations near 400m height. There appeared to be little lateral temperature variation along each E-W section within the atmospheric boundary layer. Boundary layer winds were strong and from the north throughout the flight, with maximum speeds around 25-35 knots. There was a bit of a jet structure to the boundary layer airflow, but the speed maximum was not always coincident with the temperature inversion. Instead, the boundary layer wind speeds were rather constant throughout the 60m to ~400m height range.

(Disclaimer - These descriptions are from looking at computer graphical displays while aboard the aircraft, and closer inspection of post-flight data products will provide more accurate conclusions, some of which may differ from statements here.)

Data products will be available from http://www.marine.unc.edu/cool/COAST or they may be retrieved from the real-time results area. Both of these are buttons off of the main COAST site.

Submitted by:
John Bane
May 25, 2001