Forcings in GISS Climate Model
Land Use/Land Cover
Conversion of Natural Vegetation to Cropland and Pasture
The dominant mode of land-cover change over the last millennium is the replacement of natural vegetation with crops and pasture, and occasionally vice versa. We have used a number of estimates of these changes from Pongratz et al. (2008), Kaplan et al. (2010) and the HYDE3.1 database (Klein Goldewijk et al., 2011), which can be downloaded from:
Prior to CMIP5, we used data from Ramankutty and Foley (1999).
Irrigation
The use of transient irrigation estimates as a climate forcing in the GISS GCM was pioneered by Puma and Cook (2010) and Cook et al (2015).
The gridded monthly data for irrigation (mm/day) from 1848 to 2002 are available here (netCDF).
Contact
Please address inquiries about these data to Dr. Benjamin Cook.
References
Cook, B.I., S.P. Shukla, M.J. Puma, and L. Nazarenko, 2015: Irrigation as an historical climate forcing. Clim. Dyn., 44, 1715-1730, doi:10.1007/s00382-014-2204-7.
Kaplan, J. O., Krumhardt, K. M., Ellis, E. C., Ruddiman, W. F., Lemmen, C., and Klein Goldewijk, K., 2010: Holocene carbon emissions as a result of anthropogenic land cover change, The Holocene, 21, 775-791, doi:10.1177/0959683610386983.
Klein Goldewijk, K., Beusen, A., van Drecht, G., and de Vos, M., 2011: The HYDE 3.1 spatially explicit database of human-induced global land-use change over the past 12,000 years, Global Ecol. Biogeogr., 20, 73-86, doi:10.1111/j.1466-8238.2010.00587.x.
Pongratz, J., C. H. Reick, T. Raddatz, and M. Claussen, 2008: A reconstruction of global agricultural areas and land cover for the last millennium. Glob. Biogeochem. Cycles, 22, no. 3, GB3018. doi:10.1029/2007GB003153.
Puma, M.J., and B.I. Cook, 2010: Effects of irrigation on global climate during the 20th century. J. Geophys. Res., ,115, D16120, doi:10.1029/2010JD014122.
Ramankutty, N. and J. A. Foley, 1999: Estimating historical changes in global land cover: Croplands from 1700 to 1992. Glob. Biogeochem. Cycles, 1, 997–1027, doi:10.1029/1999GB900046.
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This page was written by Dr. Gavin Schmidt.
