CLOUD CLIMATOLOGY BASED ON SURFACE WEATHER OBSERVATIONS

The basic cloud cover statistics from the Surface OBServations (SOBS) cloud climatology for December 1981 through November 1991 are illustrated here. More detailed climatology statistics can be found at the Land Cloud Atlas site. There are three datasets available from the Carbon Dioxide Information Analysis Center (CDIAC): 1) Climatological Data for Clouds Over the Globe from Surface Observations, 1982-1991: The Total Cloud Edition, 2) Edited Synoptic Cloud Reports from Ships and Land Stations Over the Globe, 1982-1991, 3) Extended Edited Synoptic Cloud Reports from Ships and Land Stations Over the Globe, 1952-1996, the original individual observations from each surface site, and the climatological statistics for land and ocean. The first versions of the latter two datasets were also released in four atlases (Warren et al. 1986, 1988, Han et al. 1994, 1995). New, revised and extended versions are now being prepared: The land results are available at the Land Cloud Atlas site. A comparison of SOBS and ISCCP cloud type statistics can be found in Hahn et al. 2001.

The original map grid interval of the SOBS cloud statistics datasets varies from 2.5 degree latitude-longitude over land areas to 5-10 degrees latitude-longitude over ocean areas. For display purposes, these datasets have been merged and re-mapped to a 2.5 degree (equivalent to the ISCCP's equal-area grid) and then converted to a globally uniform 2.5 degree grid interval.

Selections may be viewed as GIF images or downloaded in one of two formats (see the browse data format description).

Note that the variable "Land Fraction Area (%)" is used as a flag variable and the same is applied to all datasets.

References

Hahn, C.J., W.B. Rossow, and S.G. Warren, 2001: ISCCP cloud properties associated with standard cloud types identified in individual surface observations. J. Climate, 14, 11-28. (Read abstract.)

Hahn, C.J., and S.G. Warren, 1999: Extended edited cloud reports from ships and land stations over the globe, 1952-1996. Numerical data package NDP-026C, Carbon Dioxide Information Analysis Center (CDIAC), Department of Energy, Oak Ridge, Tennessee (Documentation, 79 pages).

Hahn, C.J., S.G. Warren, and J. London, 1994: Climatological data for clouds over the globe from surface observations, 1982-1991: Data tape documentation for the total cloud edition. Numerical data package NDP-026A. Available from Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee (Documentation, 39 pages).

Hahn, C.J., S.G. Warren, and J. London, 1995: The effect of moonlight on observation of cloud cover at night, and application to cloud climatology. J. Climate, 8, 1429-1446.

Hahn, C.J., S.G. Warren, J. London, R.M. Chervin, and R. Jenne, 1984: Atlas of simultaneous occurrence of different cloud types over land. NCAR Tech. Note, NCAR/TN-241+STR, 216 pp., National Center for Atmospheric Research.

Hahn, C.J., S.G. Warren, J. London, R.M. Chervin, and R. Jenne, 1990: Atlas of simultaneous occurrence of different cloud types over land. NCAR Tech. Note, NCAR/TN-241+STR, 21 pp. + 188 maps.

Hahn, C.J., S.G. Warren, J. London, R.M. Chervin, and R. Jenne, 1982: Atlas of simultaneous occurrence of different cloud types over the ocean. NCAR Tech. Note, NCAR/TN-201+STR, 212 pp., National Center for Atmospheric Research.

Hahn, C.J., S.G. Warren, J. London, R.M. Chervin, and R. Jenne, 1990: Atlas of simultaneous occurrence of different cloud types over the ocean. NCAR Tech. Note, NCAR/TN-201+STR, 35 pp. + 188 maps.

Hahn, C.J., S.G. Warren, J. London, R.L. Jenne, and R.M. Chervin, 1988: Climatological data for clouds over the globe from surface observations. Numerical data package NDP-026, Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee (Documentation, 54 pages).

Warren, S.G., and C.J. Hahn, 2002: Cloud climatology. Commissioned article for Encyclopedia of Atmospheric Sciences (Oxford University Press), in press.

Warren, S.G., C.J. Hahn, and J. London, 1985: Simultaneous occurrence of different cloud types. J. Clim. Appl. Meteorol., 24, 658-667.

Warren, S.G., C.J. Hahn, J. London, R.M. Chervin and R.L. Jenne, 1986: Global distribution of total cloud cover and cloud type amounts over land. NCAR Tech. Note, NCAR/TN-273+STR, 29 pp. + 200 maps.

Warren, S.G., C.J. Hahn, J. London, R.M. Chervin and R.L. Jenne, 1988: Global distribution of total cloud cover and cloud type amounts over the ocean. NCAR Tech. Note, NCAR/TN-317+STR, 41 pp. + 170 maps.

Warren, S.G., J. London, and C.J. Hahn, 1991: Cloud hole over the United States? Bulletin of the American Meteorological Society, 72, 237-238.

ISCCP Data Available On-Line