Some analyses of updated SSU data –merging Nash data with NOAA-11 and NOAA-14 –derived trends,...

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Some analyses of updated SSU data

– merging Nash data with NOAA-11 and NOAA-14– derived trends, solar cycle– comparisons with NCEP/ERA40/HALOE data

SSU: ~10-15 km thick layer temperatures

data from NOAA operational satellites

NOAA-11

NOAA-14

note flattening of trends since

~1995

small long-term cooling in

middle strat.

MSU4 trends 1979-2004

SSU15x trends 1979-2004

NOAA-14 NOAA-11

NOAA-11 NOAA-14

Annual average trends 1979-2004

Model vs. observed trends (1979-1997)

Shine et al., 2003

x

1979-2003trends

How do we interpret stratopause variability?

?

~45-60 km

How do we interpret stratopause variability?

?

~45-60 km

Model vs. observed trends (1979-1997)

Shine et al., 2003

x

1979-2003trends

x why are middlestratospheretrends so small ?

Seasonal trends (N11)

SSU vs. HALOE

SSU 27~35-50 km

HALOEintegrated toapproximate

SSU 27

SSU vs. HALOE

SSU 47x~43-57 km

HALOEintegrated toapproximate

SSU 47x

Problems in operational analyses / reanalyses due to changes in satellite instruments

verticallyintegrated toapproximateSSU 36x(~35-50 km)

Global mean 100 hPa temps from analyses / reanalyses

Note spurious changes due to evolution

of data / analysis systems

TOVS – ATOVS change

each data setnormed to

zero for1992-1999

Temperature solar cycle 1979-2003

NOAA-11 NOAA-14

Observations vs. model

FUB model, Matthes et al., 2004

Observed ozone andtemp changes

40 km ozone

35-50 kmtemperature

note coherentvariability

(temperaturesrespond to

ozone)

Some key points:

• Significant differences between updated record using NOAA-11 and NOAA-14 data

• Strong upper stratosphere cooling ends after ~1995(reasonable agreement with HALOE data)

• No significant trends in tropical lower stratosphere in MSU4 and SSU15x data (very different from radiosondes)

• Small global trends in middle stratosphere (different from models)

• Reanalysis data sets problematic for trends

• Solar cycle ~1 K, maximizes in tropical middle-upper stratosphere

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