# Presentation: 919949

## Independent Analysis of MSU2 Temperature Time Series

**F. Wentz, C. Mears, and M. Schabel**
**Remote Sensing Systems, Santa Rosa, CA**
-    Orbit Decay, [Wentz & Schabel, *Nature*, August 1998]
-     NRC Panel on Reconciling Temperature Observations
-     NOAA Climate and Global Change Program Grant to RSS

- RSS:   0.10 Co/decade (1979-2001)
- UAH:   0.01 Co/decade (1979-2001)
- Expected error  0.03 Co /decade (2 sigma)

## Ocean-Only Merging Procedure 1

**Notes:**
Top Plot – Raw Global Pentads From Each Satellite, Color coded by Sat.  Obviously need intersatellite offsets
Middle Plot – Blue dots are Intersatellite differences.  Note that the relative vertical scale is the same – 4K, so much of what looked like noise is actually pentad to pentad variability.  Theres is clearly seaosnal scale structure in the differences.   As pointed out by Spencer and Christy, these are strongly correlated with calibration target temperature.  The red dots are a fit to the differences that includes the calibration target temperature.
Bottom plot.  After the fit residuals.  Note the expanded vertical scale.  Fit accounts for almost all structure – left with noise – instrument noise and sampling noise.

## Ocean-Only Merging Procedure 2

-  =  + TH

**Notes:**
Top Plot – Raw Global Pentads From Each Satellite, Color coded by Sat.  Obviously need intersatellite offsets
Middle Plot – Blue dots are Intersatellite differences.  Note that the relative vertical scale is the same – 4K, so much of what looked like noise is actually pentad to pentad variability.  Theres is clearly seaosnal scale structure in the differences.   As pointed out by Spencer and Christy, these are strongly correlated with calibration target temperature.  The red dots are a fit to the differences that includes the calibration target temperature.
Bottom plot.  After the fit residuals.  Note the expanded vertical scale.  Fit accounts for almost all structure – left with noise – instrument noise and sampling noise.

## Ocean-Only Merging Procedure 3

**Ocean-Only Merging Procedure 3**

-  =  + TH

**Notes:**
Top Plot – Raw Global Pentads From Each Satellite, Color coded by Sat.  Obviously need intersatellite offsets
Middle Plot – Blue dots are Intersatellite differences.  Note that the relative vertical scale is the same – 4K, so much of what looked like noise is actually pentad to pentad variability.  Theres is clearly seaosnal scale structure in the differences.   As pointed out by Spencer and Christy, these are strongly correlated with calibration target temperature.  The red dots are a fit to the differences that includes the calibration target temperature.
Bottom plot.  After the fit residuals.  Note the expanded vertical scale.  Fit accounts for almost all structure – left with noise – instrument noise and sampling noise.

## Comparisons of Target Multiplier  

-  =  + TH

## Ocean-Only Merge, RSS Target Factors

-  =  + TH

**Ocean-Only Merge, ****RSS**** Target Factors**

**Notes:**
Top Plot – Raw Global Pentads From Each Satellite, Color coded by Sat.  Obviously need intersatellite offsets
Middle Plot – Blue dots are Intersatellite differences.  Note that the relative vertical scale is the same – 4K, so much of what looked like noise is actually pentad to pentad variability.  Theres is clearly seaosnal scale structure in the differences.   As pointed out by Spencer and Christy, these are strongly correlated with calibration target temperature.  The red dots are a fit to the differences that includes the calibration target temperature.
Bottom plot.  After the fit residuals.  Note the expanded vertical scale.  Fit accounts for almost all structure – left with noise – instrument noise and sampling noise.

## Ocean-Only Merge, UAH Target Factors

**Ocean-Only Merge, ****UAH ****Target Factors**

-  =  + TH

## Global Trend Comparison MSU Channel 2

- Ocean Only

- Land Only

- Land and Ocean

- C&S

- RSS

- RSS

- RSS

- C&S

- C&S

- RSS:   0.10 Co/decade
- UAH:  -0.01 Co/decade

- RSS:  0.09 Co/decade
- UAH:  0.05 Co/decade

- RSS:  0.10 Co/decade
- UAH:  0.01 Co/decade

- Much of the
- Difference due to NOAA-9

## MSU Channel 2 Trend Map Comparison

- RSS

- UAH

- RSS – UAH

## Comparisons with other Datasets

- Differences

- Radiosondes are warmer in early years
- MSU2 Annual Radiosonde Comparison29 Stations with VIZ Sondes + Minquin
- _Mean Trend at These Sites_
- RSS:	0.17 Co/decade
- UAH:	0.11 Co/decade
- _Global Trend_
- RSS:	0.10 Co/decade
- UAH:	0.01 Co/decade

**NOAA-9**

- SSTs are cooler in early years
- MSU2 Compared to Reynolds SST
- Tropics:  20S to 20 N

**Comparisons with other Datasets**

- 0.50

- 0.25

- 0.00

- -0.25

- -0.50

**Notes:**
The radiosonde data was obtained by digitizing the Figure we got from John Christy via email – We have not done our own radiosonde comparison
We are closer to each other than either of us is to the radiosondes and the main difference is from 1985 and before.

##                            A Way Forward

**  ****Two groups exchange software and data**
**     ****to better understand differences**
**  ****Comparisons with other observational datasets**
-   MSU1 and MSU4
-   Radiosondes (trends and diurnal signals)
-   SST (buoys and satellites)
-   Land Surface temperature from satellite microwave radiometers
-   Vapor from satellite microwave radiometers
**  ****Comparisons with Climate Models**