noaa environmental technology laboratory gary a. wick observed differences between infrared and...

Gary A. Wick NOAA Environmental Technology Laboratory

Observed Differences BetweenInfrared and Microwave Products

Detailed comparisons between infrared and microwave SST products show complex spatial and temporal differences.


Data Sources

• Infrared– AVHRR

• Operational NLSST - Naval Oceanographic Office

• Microwave– TRMM Microwave Imager (TMI)

• Remote Sensing Systems – Wentz and Gentemann

• Buoys– QC’d GTS buoys via NCEP/CDC


Potential Microwave Error Contributions

3-D look-up table considering wind speed, SST, and water vapor


Estimated Microwave Bias


Stability Impact


Potential Infrared Error Contributions

2-D look-up table considering water vapor and SST


Estimated Infrared Bias


Infrared Aerosol Error Contributions

• Derived from matches with TMI


Impact of Bias Corrections

Bias: 0.21 K

STD: 0.44 K

Bias: -0.02 K

STD: 0.27 K


Impact on OI Analysis

August 2000

• No Corrections– bias: 0.08 K– rms: 0.61 K

• With Corrections– bias: -0.01– rms: 0.59


New Humidity and Temperature Products

• Produced new near-surface specific humidity and air temperature products

• Combination of SSM/I and AMSU• Retrieval derived through regression to cruise

observations


What Factors Explain the Differences

• Simple linear correlation analysis• Quantities readily in MW products + Ta/qa

• Leading terms qs-qa and Ts-Ta

• Applies to both TMI and MCSST• Highly sensitive to choice of surface

temperature


TMI Results


MCSST Results


Additional MCSST Impact

noaa environmental technology laboratory gary a. wick observed differences between infrared and...

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