Atmospheric forcing fields have been prepared for 06Z 1 August - 06Z 15 September 2009. Available variables include wind stress,
net heat flux, evaporation-precipitation, and shortwave radiation. These fields have been primarily prepared from the direct fluxes of an
18km resolution COAMPS archive; the wind stress is a combination of the 18km COAMPS archive winds and a set of nested 15km/5km COAMPS winds
(available in real-time).
The final fields are the result of a two-year study during which we carefully compared and evaluated available data sets: flux by flux and field
by field. We subsequently selected what we determined was the most appropriate combination of re-analysis products and gridded those on 4 different
grids at different resolutions. We then selected the highest resolution among all available fields and compiled/combined/merged them into our best
estimates of the atmospheric forcing.
A complete description of the numerous comparisons and evaluations carried out, the fields and their composition is available
The 18km COAMPS and nested 15km/5km COAMPS data sets were chosen as the basis
for the final product set because:
- all the direct observations necessary to calculate the MSEAS forcing are available
- no bulk formula calculations are required
- there is complete spatial and temporal coverage of the area of interest
- spatial and temporal resolutions are adequate
- available observations are self-consistent (from one model)
The available physical regions are shown below:
- 7.24S-45.6N, 94.88-185.08E at 5km resolution
- 16-31N, 115-131E at 5km resolution
- the 4.5km resolution MSEAS real-time modeling domain
- the 1.5km resolution MSEAS real-time modeling domain.
A subset of the specific evaluations carried out includes:
- Precipitation - compared COAMPS and NOGAPS total precipitation for
7-9 Aug., 30-31 Aug. and 9-10 Sep
- Direct versus bulk formulae - compared direct and bulk
formulae calculations of E-P, net heat and wind stress from COAMPS and NOGAPS
- Components of net heat - compared components of
heat flux (shortwave radiation, sensible heat, latent heat and backscatter) from direct and bulk formulae calculations
- Cloud cover - determined ramifications of cloud cover and SST availability
in the various products
- Real-time versus nested - compared real-time COAMPS and NOGAPS
with nested 15km/5km COAMPS
- Real-time - compared fields received daily in real-time from
COAMPS and NOGAPS
We thank the Office of Naval Research for generous support of this research. At ONR we thank Ching-Sang Chiu, Ben Reeder, Terri Paluszkiewicz, and
Ellen Livingston for their assistance throughout the QPE program. In addition, we thank G. Gawarkiewicz, T. Duda, J. Sen, B. Cornuelle, J. Lynch, P. Niiler,
L. Centurioni, C. Lee, R.-C. Lien, T. Sanford, L. Mayer, B. Calder, and Y.-T. Lin for data and discussions. We also thank J. Doyle, D. Marble, J.
Nachimkin, and J. Cook as well as the FNMOC for providing us with atmospheric fluxes.