DOI: 10.5061/dryad.sn02v6xf9
title: Projected increases in exposure to climate extremes across global vertebrate diversity hotspots

description: Climate change intensifies climate extremes globally, threatening
 biodiversity. Vertebrates vulnerable to climate extremes are identified by
 the International Union for Conservation of Nature (IUCN), though future
 changes in exposure to climate extremes for these species remain unclear.
 Using CMIP6 climate models under four Shared Socio-economic Pathways, we
 projected changes in extreme drought, heat, and precipitation frequencies
 globally between 1974–2014 and 2050–2090 for 1,634 terrestrial vertebrates
 considered threatened by climate extremes, focusing on 33 global
 vertebrate diversity hotspots. Results indicate substantial increases in
 climate extremes, with tropical regions facing the highest increases in
 extreme heat and drought. Hotspots with few climate extreme-threatened
 vertebrates often face the highest increases in climate extreme
 frequencies, suggesting vertebrate vulnerability within numerous hotspots
 is understudied. These results highlight the need to incorporate climate
 projections into conservation assessments, and for targeted research on
 climate extreme effects on tropical vertebrates, which may have lower
 tolerances to climatic change than temperate counterparts.
description: We used global standardized precipitation index (SPI) and
 temperature data to calculate past and future climate extreme occurrence.
 To this end, we used four Global Climate Models (GCM) and four
 Representative Concentration Pathways (RCP), for a historical and future
 period, from CMIP6 projections.  We analyzed changes in drought exposure
 across species ranges considered by IUCN to be threatened by three types
 of climate extremes, and across 33 global vertebrate diversity hotspots
 holding about 85% of global vertebrate diversity.
description: # Projected increases in exposure to climate extremes across global
 vertebrate diversity hotspots
 [https://doi.org/10.5061/dryad.sn02v6xf9](https://doi.org/10.5061/dryad.sn02v6xf9) ## Description of the data and file structure There are three scripts associated with this analysis: **1.Rawdata_Processing.R** - Contains all code necessary to transform the raw climate data from C3S repository of CMIP6 data into monthly rasters. -Associated files: none **2.Change_calculations.R** -  Contains all code necessary to transform the SPI and Temperature data for historical and future periods into rasters of change climate extremes. -Associated files: none **3.Fig 1** - Contains all code necessary to run the analysis used to obtain the results and result visualizations. **4.Fig 2** - Contains all code necessary to run the analysis used to obtain the results and result visualizations. **5.Fig 3** - Contains all code necessary to run the analysis used to obtain the results and result visualizations. -Associated files:   jenkinshotspots.shp ### Files and variables #### File: Jenkinshotspots.zip **Description:** 33 global hotspots of vertebrate diversity, based on [https://doi.org/10.1073/pnas.130225111](https://doi.org/10.1073/pnas.1302251110) ## Code/software All analysis was performed using R Studio version 4.3.2. Packages needed to run all analysis are contained within their respective scripts. ## Access information Data was derived from the following sources: * The 33 hotspots of global vertebrate diversity were based on data from [https://doi.org/10.1073/pnas.130225111](https://doi.org/10.1073/pnas.1302251110) * The shapefiles of vertebrates considered by the IUCN to be threatened by the three types of climate extremes were downloaded from the IUCN website. The shapefiles may not be reuploaded in Dryad, but instructions on how to replicate our database search are found within the R script to create Figure 1.