Data and code for Winter conditions structure extratropical patterns of species richness of amphibians, birds, and mammals globally

This repository contains the dataset analyzed in 'Winter conditions
structure extratropical patterns of species richness of amphibians, birds,
and mammals globally' - published in the journal Global Ecology and
Biogeography - and the R code used to generate the correlations,
generalized additive models, and related figures presented in the
manuscript. Column descriptions for the data can be found in the
associated README.txt file. Please refer to the manuscript for further
detail on the variables and how they were derived. The Winter Indices
(WIs) were derived using satellite remote sensing data from optical
(MODIS, snow cover) and microwave (MEaSUREs freeze/thaw, frozen ground)
sensors. The species richness maps were derived using IUCN range maps for
individual species of amphibians, birds, and mammals (data requests can be
made here: https://www.iucnredlist.org/resources/spatial-data-download).
Climatic varibales were derived from WorldClim v2.0 data, elevation from
USGS GMTED2010 data, and primary productivity from the cumulative dynamic
habitat index available here: http://silvis.forest.wisc.edu/maps-data/.