IMET BUOY - FLUX DATA (Release 2.5b)

S. Anderson (WHOI, USA)
R. Weller (WHOI, USA)

Announced availability: 1 October 1994

Data Access

Updated processed IMET buoy air-sea flux data are available from the COARE Moored Data Archive at NOAA/PMEL's Tropical Atmosphere-Ocean Array (TAO) Project Office, (http://www.pmel.noaa.gov/coare/coare-data.html), where COARE mooring data reside. The original processed data are available from (1) the Florida State University Center for Ocean-Atmospheric Prediction Studies (COAPS) (http://www.coaps.fsu.edu/coare/), the repository for COARE surface meteorology and flux data, and (2) the Pennsylvania State University Department of Meteorology Field Project Data Archive (http://wwwarc.essc.psu.edu), which holds the COARE radiation datasets.

The original data have also been archived at NOAA's National Climatic Data Center (NCDC) in Asheville, North Carolina (http://www.ncdc.noaa.gov), along with other meteorological COARE data, and at the National Center for Atmospheric Research (NCAR) in Boulder, Colorado (http://dss.ucar.edu/pub/toga_coare/), the site of the TOGA COARE deep archive.

The subsurface data obtained from the WHOI IMET mooring are available from the NOAA/PMEL site as well.

Background

The Woods Hole Oceanographic Institution (WHOI) surface mooring was deployed in the center of the Intensive Flux Array (IFA) at 156 E, 1 45'S during the COARE Intensive Observing Period (IOP).

Data File Information

Directory name: IMET_flux
Number of data files: 1 (WHOIbuoy2b.dat)
Number of documentation files: 1 (IMET_flux.readme)
Dataset format: ASCII
Dataset volume: 135 KB

Release 2.5b (27 December 1995)

Notes: An error in the calculation of time of solar noon was discovered and corrected. The Bulk Flux code version 2.5 was modified and re-run to produce version 2.5b of the flux dataset.

Release 2.5a (31 October 1995)

Notes: The TOGA COARE Bulk Flux code vers.2.5 is used. A change in the exchange coefficient effectively lowers the sensible and latent heat fluxes on average by 3-5%. There are also slight changes to latent heat flux, skin temp, and wind stresses. These changes in the algorithm are the result of the TOGA COARE Air-Sea Flux Working Group meeting held at the University of Hawaii, 2 - 4 August 1995.

The sign of the heat fluxes are now consistent so that a positive heat flux is a positive heat gain of the ocean.

The time stamp marks the beginning of each hourly average.

Release 1.0b (8 August 1994))

Notes:
- The wind speed is now the measured wind speed rather than the relative as given in the previous release.
- The surface temperature (stmp) is now the measured temperature at .45 m depth. The Tskin is the sea surface skin temperature and is now an additional output.
- The TOGA COARE Bulk Flux Code vers.2.0.b is used. The output of Tskin is corrected in this version to include the cool skin which was previously not included.

Release 1.0 (3 August 1994)

WARNING: This is a preliminary processed file and should be used with caution. Please forward an email message to S. Anderson or R. Weller after picking up the data. Users will be placed on a mailing list and notified when the file is updated.

The surface fluxes were estimated using the TOGA COARE Bulk Flux Code, Ver. 2.0. (Fairall et al. 1996a). The warm layer and cool skin estimates are from Fairall et al. (1996b). The rain data were derived from a combination of observations from various surface-observing platforms. These platforms include the WHOI surface buoy, R/V Wecoma, R/V Moana Wave and the ATLAS buoy at 2S. The wet bulb temperature was used as an estimate of the rain temperature. The rain data have been block-averaged over 24 hours.

Wind velocities are relative to the sea surface and calculated by subtracting the surface currents from the observed winds. Wind vectors are given as oceanographic convention (direction towards).

The sea surface temperature was estimated using the COARE bulk flux algorithm which includes a warm layer extrapolation of the measured sea surface temperature (at 0.45 m) to the surface and a cool skin correction.

A four-day gap from 9 December 00:33:45 to 13 December 1992 05:11:45 was filled with hourly data from Mike McPhaden's (NOAA/PMEL) nearby ATLAS buoy (156 E, 2 S). Data were regridded to IMET buoy sample interval (wind, rh, sst, atmp). The previous four days of SW and BP were duplicated and patched into the gap as a temporary solution for these missing variables.

Notes:
- The file is uniformly spaced in time; averaging interval = 60 minutes.
- Some gaps were present and the time series was linearly interpolated in time to fill these gaps.
- Magnetic variation correction has been applied = +7.67 degrees

Release 1.0b (8 August 1994))

Notes:
- The wind speed is now the measured wind speed rather than the relative as given in the previous release.
- The surface temperature (stmp) is now the measured temperature at .45 m depth. The Tskin is the sea surface skin temperature and is now an additional output.
- The TOGA COARE Bulk Flux Code vers.2.0.b is used. The output of Tskin is corrected in this version to include the cool skin which was previously not included.

File Header
 

Latitude = -1.755540 Longitude = 155.994507
Output file processing depth bins
     start rec =     1  0.000000m
       end rec =     1  0.000000m
Output file processing records
     start rec  10/21/1992  19:33:45
       end rec  03/04/1993  00:03:45
The following are positive for ocean cooling.
     qlat      W/m**2       Latent heat flux
     qsen      W/m**2       Sensible heat flux
     qlw       W/m**2       Net Longwave radiation
The shortwave radiation is positive for ocean heating.
     qsw       W/n**2       Net Shortwave radiation
     taue      N/m**2       East component of wind stress
     taun      N/m**2       North component of wind stress
     rain      mm/hr        rainfall rate
     Train     degC         rainfall temperature (wet bulb temp)
     atmp      degC         air temperature (adjusted for solar heating error)
     time      UTC          Time at beginning of the averaging interval
     wnde      m/s          relative wind east component
     wndn      m/s          relative  wind north component
     hrh       percent      relative humidity
     bpr       mb           barometric pressure
     stmp      degC         sea surface temperature (measured)
     Tskin     degC         sea surface skin temperature (from Ver.2 code)
Measurement heights above the sea surface:
     wind cup       3.54m
     wind vane      3.26m
     hrh            2.74m
     atmp           2.78m
     bpr            3.00m
     stmp           0.45m
     swadj2         3.54m
     lwadj          3.54m

Data Example
 

year      month    day     hour    min     sec    Qlat     Qsen    Qlw     Qsw     Rain   Train    Taue    Taun    Atmp    Stmp     HRH    BPR     Wnde   Wndn    Tskin

   1992      10      21      19      33      45  231.31   32.62   74.73   72.83    0.02   24.49 0.00626 0.23299   27.29   29.49   85.97 1008.40    0.53   11.08   29.28
   1992      10      21      20      33      45  221.64   24.03   76.09  210.41    0.00   24.21 0.00171 0.18407   27.67   29.46   83.02 1009.35    0.39   10.13   29.26
   1992      10      21      21      33      45  198.07   17.79   65.24  438.26    0.00   24.48 -0.02044 0.15655   28.06   29.45   82.79 1010.01   -0.74    9.51   29.31
   1992      10      21      22      33      45  190.81   17.84   65.14  646.51    0.00   24.83 -0.05513 0.15978   28.15   29.46   84.05 1010.11   -2.76    9.27   29.38
   1992      10      21      23      33      45  168.46   13.02   59.64  511.21    0.02   24.92 -0.05605 0.11415   28.41   29.49   83.54 1009.90   -3.36    7.98   29.40
   1992      10      22       0      33      45  161.41   15.54   57.06  699.03    0.08   25.24 -0.05739 0.11403   28.30   29.51   85.42 1009.25   -3.54    7.98   29.48
   1992      10      22       1      33      45  165.35   15.04   48.17  531.61    0.42   25.21 -0.07677 0.11719   28.33   29.53   85.24 1008.37   -4.64    7.77   29.45

For more information, please contact:

Robert Weller
Physical Oceanography Department
Clark 204A
Woods Hole Oceanographic Institution
Woods Hole, MA 02543
USA

email: rweller@whoi.edu
Phone: (508) 457-2000 x2508
FAX: (508) 457-2181

OR

Steven Anderson
Physical Oceanography Department
Clark 204A
Woods Hole Oceanographic Institution
Woods Hole, MA 02543
USA

email: sanderson@whoi.edu
Phone: (508) 457-2000 x2876
FAX: (508) 457-2181

References

Fairall, C.W., E.F. Bradley, D.P. Rogers, J.B. Edson, G.S. Young 1996: Bulk parameterization of air-sea fluxes for TOGA COARE. JGR (in press).

Fairall, C.W., E.F. Bradley, J.S. Godfrey, G.A. Wick, J.B Edson, and G.S. Young, 1996: The cool skin and the warm layer in bulk flux calculations. JGR (in press).

Weller, R.A., and S.P. Anderson, 1996: Surface meteorology and air-sea fluxes in the western equatorial Pacific warm pool during TOGA Coupled-Ocean Atmosphere Response Experiment. J Climate, Vol 9., No. 8, pp 1959-1990.

Acknowledgements

These data were collected with support from the U.S. National Science Foundation (Grant OCE91-10559). If any of these data are being used in a publication, please acknowledge Dr. Robert Weller and the Woods Hole Oceanographic Institution.

We gratefully acknowledge Clayton Paulson (OSU, USA), Chris Fairall (NOAA/WPL, USA) and Mike McPhaden (NOAA/PMEL, USA) for sharing their observations.

Return to Mooring Data Overview
Return to TOGA COARE Data User's Guide Table of Contents
Return to the COARE Homepage