1. Satellite Data for CLIMODE
Kathie Kelly
Suzanne Dickinson
University of Washington
Applied Physics Lab
CLIMODE PIs Meeting
WHOI, September 2005

2. Satellite Data
Near real time data provided for cruises (from Remote Sensing Systems and CCAR)
See web site for more detail on delivery and Matlab program(s) to read/display data
Feedback on real-time before cruises PLEASE
Research quality data will be archived for use by all (lag for processing/quality control)
Research products (SSH, microwave SST, wind stress, air-sea fluxes)

3. Questions: Over what time period is real-time data needed?
(from 2 weeks before cruise?)
How will data be accessed? (APL or WHOI web site?)
Ship-to-shore link and backup? Inmarsat

4. SST from Microwave Sensors
Optimally interpolated SST from Remote Sensing Systems

5. SSH from Multiple Altimeters
SSH Anomaly from CCAR plus Mean SSH from Dong & Kelly (Hydrobase)

6. QuikSCAT Winds in Swaths
Approximately 0900 UTC
Approx. 110 minutes later
Winds from Remote Sensing Systems

7. QuikSCAT Winds in Swaths
Approximately 2100 UTC
Approx. 110 minutes later
Winds from Remote Sensing Systems

8. Detail of QuikSCAT Winds
Winds from Remote Sensing Systems

9. Weather Forecasts and Warnings
Joseph Sienkiewicz of NCEP’s Marine Forecast Center has offered to provide special forecast and warning support for the cruises (QuikSCAT user and collaborator)

10. CLIMODE-related studies of air-sea interaction
LuAnne Thompson
David Trossman
Kathie Kelly
University of Washington
CLIMODE PIs Meeting
WHOI, September 2005

11. Storm Track Steering by Strong Currents
Meridional QuikSCAT wind stress variance (proxy for cyclone activity)
Maximum along Gulf Stream path (black)
Similar for major current systems (Nakamura et al., 2004)
Gulf Stream currents evident in QuikSCAT winds (Chelton et al., 2004)

12. Are heat content changes related to other climate indices
Are heat content changes related to other climate indices? Heat Content Principal Components (EOFs)
EOF 1: 26% of variance
EOF 2: 16% of variance
Mode 1: WBCs in phase -- Arctic Oscillation Index
Mode 2: Pacific mode -- Pacific Decadal Oscillation
Wrong sign to be ocean response to cooling by winds!
Data from Joint Environmental Data Analysis Center

13. Heat Content and Heat Fluxes
January 2000
Regression of NCEP net flux onto heat content mode 1: high heat content => high oceanic heat loss
Anomalies are about 20% of annual mean flux

14. Ekman pumping estimates including geostrophic currents
QuikSCAT scatterometer wind stress
Geostrophic currents from altimeter
Similar to L. Thomas method, but no assumptions on velocity/current geometry

15. Effect of Ocean Currents on Wind Stress (as measured by scatterometer)

16. TAO - QuikSCAT winds = ADCP velocity

17. Iterative method for estimating Ekman currents
Vertically integrated x-mom equation in the Ekman layer assuming:
No vertical shear in geostrophic currents
Geostrophic currents obey quasi-geostrophic dynamics:
Terms like are small.
Initial guess for Ekman current stepped forward in “time” until a steady state is reached for weekly fields with R =1 day-1 (~ 10 hours)

18. Geostrophic currents from altimeter
Zonal
Merged AVISO altimeter data, weekly at 1/3o
AVISO mean SSH (includes Levitus, drifters, and GRACE data)
Smoothed to remove effects of subtracks
Meridional

19. Mean vorticity from geostrophic currents
Ratio of vorticity to Coriolis parameter

20. Effect of currrents on Ekman suction (wE)
Winter 2000 without currents
Winter 2000 with currents

21. Annual mean Ekman suction (wE, meters per day)

22. . Subduction rate The Ekman vertical velocity is given by
Following Marshall et al (1993) .
Overbar - annual average
No vertical shear in geostrophic velocity
H - Levitus March mixed-layer depth.