Grace Su ( grace@seawifs.gsfc.nasa.gov) (301) 286-9494
Applicant's Name: Andrew Thomas
Institution: University of Maine
Address: School of Marine Sciences
Libby Hall
Orono, ME 04469-5741
Telephone: 207-581-4335
Fax Number: 207-581-4388
E-mail Address: thomas@maine.edu
Type of Temporary Agreement requested:
An agreement that temporarily allows an existing real-time SeaWiFS HRPT
station to release data to the Authorized Users listed below.
Time period of temporary agreement:
(1) Start Date (month/day/year): 04/17/2003
End Date (month/day/year): 05/21/2003
(2) Start Date (month/day/year): 07/10/2003
End Date (month/day/year): 08/11/2003
SeaWiFS HRPT Station to provide data: HUAF
List of Authorized Users to access real-time data.
1. Andrew Thomas
2. P. Ted Strub
3. Peter Brickley
Project Title: GLOBEC: Northeast Pacific
Principal investigator(s): Andrew Thomas
Funding Agency(s): NSF/NOAA COP
Description of the Research Project and Justification for Real-time SeaWiFS Data:
GLOBEC Northeast Pacific field studies require both spatial and temporal context. Our primary
goal is to quantify variability in small scale and mesoscale circulation patterns in each of the
process studay sites, and to relate changes in this variability in the strength of forcing by local
winds and basin scale circulation. We approach this goal through a systematic analysis of spatial/
temporal scales utilizing satellite data measurements at appropriate resolutions. Our work defines
and quantifies a) small event-scale coastal features such as fronts, eddies and convergences (order
50m - 100km)(These are most directly linked to local success/survival of the GLOBEC target
species.). b) mesoscale circulation/seasonal variability over the shelf, upwelling fronts, coastal
jets, buoyant plumes and eddies (order 10km - 500km). A second, related goal is to quantify
changes in the timing and strength of seasonal transitions in both study regions. Temporal
variability is an integral component of biological/physical interaction. We begin with an analysis
of the spring transition in the California Current and then apply our analysis protocols to the
Coastal Gulf of Alaska (CGOA). A thrid goal is to determine changes in the upwelling strength,
cross-margin transport and potential for entrainment of biological populations into the seasonal
offsore jet as characterized by high resolution satellite measurements of evolving fronts, jets and
the width of the upwelling zone. Our analysis will include mesoscale and small scale variability
studies to coincide with GLOBEC process studies and other (e.g. LTOP) field work.
Specific objectives of the proposed work are divided into two mutually dependent aspects of
satellite oceanography. 1) We will acquire process, subset QC, archive and make available
electronically, surface temperature (SST), ocean color (chlorophyll), altimeter and high resolution
SAR imagery of the NEP region at multiple scales suitable for basin, mesoscale and small scale
coastal analyses. 2) We will analyze these data, in conjunction with ancillary data, to both define
optimal products and to address our GLOBEC research goals at each of the spatial/temporal
scales. Our core data sets are altimeter fields, NOAA AVHRR and NASA SeaWiFS data at both
1km and 4km resolution and synthetic aperture radar (SAR) imagery. These are supplemented
with model and buoy winds, tide gauge sea levels and in situ data. Close collaboration with
investigators carrying out field measurements will link scales and patterns determined in the
satellite data to 3D in situ processes.
Real-Time SeaWiFS Data Justification
In the coastal Gulf of Alaska, hydrographic processes are driven primarily by salinity rather than
temperature. In such a regime, surface patterns evident in satellite ocean color data often provide
better (or at least very complimentary) indicators of hydrographic and biological fronts and
circulation features than satellite sea surface temperature. We request Real-Time SeaWiFS data
immediately preceding and during two GLOBEC cruises in the coastal Gulf of Alaska on the
shelf in the vicinity of Seward. These will be used for overall cruise design and optimal station
planning.