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CENIntegrated Climate Data Center ICDC

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Cloudcover and -type from ISCCP H-Series

ISCCP H-Series Cloudcover
ISCCP H-Series Cloudcover: Mean cloud amount July 1983. Copyright: UHH/CEN/AJB

Topics

Access

RESTRICTED:This link to the data set is only available for a restricted user group.  The data set is only accessible in CEN/MPI net or accessible from external nets with a customer account.  Please contact ICDC if you would like to access this data from outside the network.

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Description

The aim of the International Satellite Cloud Climatology Project (ISCCP) is to develop a long-term high resolution global data set of cloud parameters. This is done under the umbrella of the "World Climate Research Programme" (WCRP) and "Gloal Energy and Water Experiment" (GEWEX). Data from different satellites sensing the atmosphere of the Earth are used to obtain cloud information which can be used to derive the global cloud coverage, their characteristics and temporal variability as well as their role in the Earths' climate system and its hydrological cycle.

The list of  data which is available from ISCCP is impressive (see parameters). It depends on the data product, however. Here we offer ISCCP H-Series HGH = global gridded, 1° resolution, monthly average 3-hourly observations; the ISCCP H-Series HGG data set (as HGH but without the monthly averaging applied = successor of the ISCCP-D1 product) can be obtained on request. HGH is the final level-4 product with monthly temporal resolution and comprises a statistical analysis of the HGG data which in turn are based on the data sets of the individual sensors HGS (see the ATBD and Fig. 2 in Young et al. (2018) in references).

Available parameters include (among others) coverage (total and of different cloud types), cloud top temperature and pressure, cloud droplet distribution, and opacity. An easy description for the different types of data can be found in the parameter description. More information about the data is given in Young et al. (2018), in the ATBD, and at NOAA's ISCCP Homepage, see references.

Last update of data set at ICDC: June 13, 2019.

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Parameters

The number of parameters offered by ISCCP is too large to list them all here. We therefore refer to the ATBD, appendix C, pages 134-135, or to the HGH parameter list and for the HGG product please take a look at the HGG parameter list (see references).

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Coverage, spatial and temporal resolution

Period and temporal resolution:

  • 07/1983 to 06/2015
  • monthly average of 3-hourly observations
  • HGG: daily 3-hourly

Coverage and spatial resolution:

  • Global
  • Spatial resolution: 1 degree x 1 degree, Equal Angle Grid
  • Geographic longitude: 0.5°E to 359.5°E
  • Geographic latitude: 89.5°S to 89.5°N
  • Dimension: 180 rows x 360 columns
  • Altitude: following terrain (for surface parameters, a topography data set is included), otherwise as given in the ATBD, appendix C.

Format:

  • NetCDF

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Data quality

The ISCCP H-Series data set includes uncertainty information for the variable "cloud amount" and values of spatial and temporal standard deviations resulting from the gridding of single satellite overpass and/or scene data into the equal area grid as well as from the merging of the different satellite products. In addition, the data set includes information about the theoretically possible and actually used number of data.

This successor data set to the ISCCP D-series products benefits from a number of improvements of particularly the input data sets and with respect to the estimation of uncertainties and the accuracy of the daa products. It is noteworthy that little has changed with regard to the retrieval methodologies used between the D- and the H-series products. We refer to the ATBD and Young et al. (2018) in the references for more information.

The data set is not free of inconsistencies which result from the different spatial coverage of the input satellite data as well as from different viewing geometries which partly seem not to be corrected properly. For example, in some regions and cases the spatial extent of the METEOSAT observation disc can be identified by means of jumps in, e.g., the cloud temperature by 10K or more. While Young et al. (2018) do not provide evidence into this direction, Karlsson and Devasthale (2018) and Tzallas et al. (2019)  (see references) illustrate that the enhancements applied in the processing of the ISCCP H-series products have not resulted in a global improvement of the quality of this data set compared to the predecessor ISCCP D-series.

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Contact

Principal Investigator
William B. Rossow
NASA Goddard Institute for Space Studies
email: wbrossow (at) ccny.cuny.edu

NOAA National Centers for Environmental Information (NCEI)
International Satellite Cloud Climatology Project (ISCCP)
E-Mail: ncdc.isccp.team (at) noaa.gov

Stefan Kern
ICDC / CEN / University of Hamburg
E-Mail: stefan.kern@uni-hamburg.de<br />(stefan.kern"AT"uni-hamburg.de)

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References

Websites:

Literature:

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Data citation

Please cite the data as follows:

Young, A. H., K. R. Knapp, A. Inamdar, W. Hankins, and W. B. Rossow, 2018, The International Satellite Cloud Climatology Project H-Series climate data record product, Earth Syst. Sci. Data, 10, 583-593, https://doi.org/10.5194/essd-10-583-2018 .

Rossow, W.B. and R.A. Schiffer, 1999: Advances in understanding clouds from ISCCP. Bulletin of the American Meteorological Society, 80, 2261-2287. doi: http://dx.doi.org/10.1175/1520-0477(1999)080<2261:AIUCFI>2.0.CO;2

The ISCCP H-Series data were obtained from NOAA's National Centers for Environmental Information (NCEI) under the satellite Climate Data Record Program, https://doi.org/10.7289/V5QZ281S, last accessed: May 24, 2019.

and with the following acknowledgments:

Thanks to ICDC, CEN, University of Hamburg for data support.

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