1. Lower-Tropospheric Temperature (TLT) Climate Data Record Using NOAA/NESDIS/STAR Recalibrated MSU Observations Wenhui Wang1 & Cheng-Zhi Zou2 1IMSG at NOAA/NESDIS/STAR 2NOAA/NESDIS/Center for Satellite Applications and Research IGARSS Vancouver, Canada July 25-29, 2011
2. Outline Background Methods for Developing TLT Product Using NOAA/NESDIS/STAR Recalibrated MSU Radiances Results and Discussion Summary and Future Works
7. MSU Lower Tropospheric Temperature (TLT)TMT Affected by stratosphere cooling effect TLT: weighted average of TMT Tb at different view angles (Spencer and Christy, 1992,2003; Mears and Wentz, 2009) TLT=T3+T4+T8+T9-0.75(T1+T2+T10+T11) i=1-4, 8-10 scan positions Reduce stratosphere cooling effect
14. Methods for STAR TLT Product Diurnal Drift Effect Correction same as STAR TMT products (Zou and Wang 2009)Using RSS monthly averaged diurnal anomaly climatology Before Diurnal Correction NOAA 11 - NOAA 10 Adjust the scene radiances at different observation time to the local noon time After Diurnal Correction
15. Results 5-day averaged MSU global mean TLT & TMT time series Temporal Coverage: 1978/11-2006/9 Spatial Coverage: -82.5° – +82.5 °
16. Results: Spatial Trend Patterns (1978-2006) TLT After Orbital Drift Effect Correction TMT (channel 2) TLT Without Orbital Decay Effect Corr.
18. Summary and Future Works Generated MSU TLT product using NOAA/NESDIS/STAR recalibrated channel 2 radiances STAR TLT shows a global warming trend of 0.145 K/dec (1978-2006), STAR TLT has the smallest warming trends compared to UAH and RSS TLT products Larger differences exist during 1979 – 1986 Next Step Generate TLT product using recalibrated Advanced Microwave Sounding Unit A (AMSU-A) observations (1998 – present) Generate MSU/AMSU-A TLT merged Product
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20. Results TLT show similar trend stability as TMT (Zouand Wang, 2010) Christy bias correction (almost horizontal lines) Constant bias correction