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James Dewar presenting liquid hydrogen: Physics Today, March 2008.

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Presentation on theme: "James Dewar presenting liquid hydrogen: Physics Today, March 2008."— Presentation transcript:

1 James Dewar presenting liquid hydrogen: Physics Today, March 2008

2 Effects of Anomalies in Ancillary Data on Cloud and Radiation Products of the ISCCP and SRB Projects? (Seminar at CIRA, March, 11, 2008) by Ehrhard Raschke (Hamburg) Stefan Kinne (Hamburg) With contributions from Ely Duenas (GISS, NY) Yuan-C. Zhang (GISS, NY) William B. Rossow (GISS, NY)

3 Planetary Albedo: 31, 31, 30 % Surface temperature 15.2, 14, 14 K surface albedo 13, 15,15%

4 We intend to demonstrate that the information by ancillary data has already introduced errors into final products. We will also discuss briefly differences of ISCCP to IPCC results.

5 Ancillary data for ISCCP radiation products

6 SOLAR RADIATION Primarily affected by Insolation, clouds, aerosols, surface reflectance + “second order characteristics”

7 LONGWAVE RADIATION primarily affected by skin temperature atmospheric temperature, water vapor cloud cover and cloud top and base heights + “second order characteristics ”

8 ISCCP: Surface temperature and reflectance; water vapor & air temperature are the most important ancillary data.

9 ISCCP: All clouds: top pressure, optical thickness & amount

10 ISCCP: Cloud amounts: Total, low, middle & high

11 Deseasonalised monthly global averages of the clear sky downward solar radiation at the surface, of the projects ISCCP and SRB.

12 Downward solar at surface: left (monthly - deseasonalised vs. 1/85 to 12/88); right (annual anomalies with respect to 21 year average) ISCCP SRB

13 Anomalies of the effective surface albedo (ratios up-to-down) ISCCP clear SRB clear

14 Upward solar radiation at TOA: left (monthly - deseasonalised vs. 1/85 to 12/88); right (annual averages) ISCCP SRB

15 From

16 Longwave radiation: Skin temperature vs. emission, dw lw and its CE at surface

17 ISCCP SRB Upward (lem) and downward (lds) fluxes of longwave radiation at surface

18 Total net radiation at TOA Total net radiation at surface

19 CE of DIV DIV solarinfrared

20 A = Incident solar at TOA X = Effective surface albedo E = Emission from surface D = Outgoing solar at TOA F = Outgoing infrared at TOA Dd = CE on outgoing solar at TOA Bb = CE on downward solar at surface Ff = CE on outgoing infrared at TOA Hh = CE on downward infrared at surface Annual averages of differences between CERES and ISCCP

21 A = Incident solar at TOA X = Effective surface albedo E = Emission from surface D = Outgoing solar at TOA F = Outgoing infrared at TOA Dd = CE on outgoing solar at TOA Bb = CE on downward solar at surface Ff = CE on outgoing infrared at TOA Hh = CE on downward infrared at surface Annual averages of differences between SRB and ISCCP

22 Conclusion and Recommendation There is very strong evidence that natural and “artificial” anomalies in ancillary data cause anomalies in cloud and radiation products, which may cause (and had already caused in the past) false interpretations with respect to climate variations and their causes. We, therefore, recommend that all such ancillary data must be quality-inspected with respect to natural and “artificial” anomalies before their use in computations of cloud and radiation products. (These conclusions need to be considered also in other GEWEX data assessments!

23 “Trends” in Model results: IPCC-4AR and MPI (only)

24 observed Annual insolation in IPCC-4AR models Global averages (TSI/4) of monthly insolation at TOA: ISCCP minus SRB

25 A = Incident solar at TOA X = Effective surface albedo E = Emission from surface D = Outgoing solar at TOA F = Outgoing infrared at TOA Dd = CE on outgoing solar at TOA Bb = CE on downward solar at surface Ff = CE on outgoing infrared at TOA Hh = CE on downward infrared at surface Standard deviation of monthly radiation products of 22 IPCC- 4AR models

26 Differences to ISCCP of MPI and all IPCC models: 12 year ( ) averages A = Incident solar at TOA X = Effective surface albedo E = Emission from surface D = Outgoing solar at TOA F = Outgoing infrared at TOA Dd = CE on outgoing solar at TOA Bb = CE on downward solar at surface Ff = CE on outgoing infrared at TOA Hh = CE on downward infrared at surface

27 Clear sky emission from ground in ISCCP, SRB and CERES: global monthly averages from January 2001 to December 2003

28 Aerosol optical depth (global average over oceans) from ISCCP radiance data (Mishchenko et al. 2007, in 2 publications and at Gordon Conference) Almost 25% reduction from 1995 to 2005 ?

29 Mishchenko et al., 2007, Science

30 The path to the „truth“ must be kept clean! THANKS !

31

32 Annual average of total outgoing radiative fluxes to space for the period (except for for CERES) in W/m2. Data are displayed for three climatologies (ISC, CER, SRB), the IPCC- 4AR model median and 20 IPCC-4AR models. The ISCCP here refers to the 4 year ( ) CERES time-period.

33 Differences (1984 to 1995) of downward solar (left) and longwave (right) radiation at surface for cloudy (top) and clear skies (middle row) and of the cloud effect (bottom) cloudy clear cloud effects


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