DOI: 10.1594/pangaea.845883
title: Gridded climate data from 5 Global Climate Models (GCM) of the Last Glacial Maximum (LGM) downscaled to 30 arc seconds for Europe, with links to NetCDF files

description: Studies on the impact of historical, current and future global change require very high-resolution climate data (less or equal 1km) as a basis for modelled responses, meaning that data from digital climate models generally require substantial rescaling. Another shortcoming of available datasets on past climate is that the effects of sea level rise and fall are not considered. Without such information, the study of glacial refugia or early Holocene plant and animal migration are incomplete if not impossible. Sea level at the last glacial maximum (LGM) was approximately 125m lower, creating substantial additional terrestrial area for which no current baseline data exist. Here, we introduce the development of a novel, gridded climate dataset for LGM that is both very high resolution (1km) and extends to the LGM sea and land mask. We developed two methods to extend current terrestrial precipitation and temperature data to areas between the current and LGM coastlines. The absolute interpolation error is less than 1°C and 0.5 °C for 98.9% and 87.8% of all pixels for the first two 1 arc degree distance zones. We use the change factor method with these newly assembled baseline data to downscale five global circulation models of LGM climate to a resolution of 1km for Europe. As additional variables we calculate 19 'bioclimatic' variables, which are often used in climate change impact studies on biological diversity. The new LGM climate maps are well suited for analysing refugia and migration during Holocene warming following the LGM.
description: Current longterm monthly climate data were obtained in 30 arc seconds resolution from Worldclim (wc) http://www.worldclim.org/current. Precipitation (prec) and maximum (tmax), minimum (tmin), average (tave) surface air temperatures are extended to the LGM coastline. In addition, temperatures are corrected to preindustrial conditions (wcpi) around 1750 using the reconstructed monthly temperature data. The reconstructed monthly temperature time series for 1659-1998 (Luterbacher et al., 2004, doi:10.1126/science.1093877 and Xoplaki et al., 2005, doi:10.1029/2005GL023424) was corrected for spatial and temporal shift and the 20th century replaced by CRU TS version 1.1 obtained from http://www.cru.uea.ac.uk/cru/data/hrgThe Global Climate Model data for the Last Glacial Maximum (LGM, 21k) stem from the PMIP2 website http://pmip2.lsce.ipsl.fr. They are downscaled to 30 arc seconds resolution and contain monthly precipitation (pr), maximum (tasmax), minimum (tasmin), average (tas) surface air temperature of the LGM.19 bioclimatic variables (bioclim) of the LGM are calculated according to http://www.worldclim.org/bioclim using the downscaled GCMs. The resulting gridded data sets largely cover Europe (eu) between 13W to 40E and 35N to 70N. The resolution is 30 arc seconds (6360x4200 grid cells).
description: Supplement to: Schmatz, Dirk R; Luterbacher, Jürg; Zimmermann, Niklaus E; Pearman, Peter B (2015): Gridded climate data from 5 GCMs of the Last Glacial Maximum downscaled to 30 arc s for Europe. Climate of the Past Discussions, 11(3), 2585-2613