DOI: 10.5061/dryad.t76hdr88v
title: Data from: Climate-driven decreases in aspen’s distribution and opportunities for future expansion across the Southern Rocky Mountains

description: Overview This dataset consists of spatially explicit predictions of aspen
 habitat suitability made in support of the study "Climate-driven
 decreases in aspen’s distribution and opportunities for future expansion
 across the Southern Rocky Mountains". Below, we outlined the
 aims, methods, results, and conclusions of this study. Aim Species
 distribution models (SDMs) are widely used to understand how climate
 change may influence habitat suitability and inform climate-adaptive
 forest management. However, SDMs are often of limited use for
 understanding the range expansion potential for tree species, which often
 exhibit slow migration rates. Here, we integrate remotely sensed data
 products into an SDM to generate predictions of range shifts for quaking
 aspen (Populus tremuloides Michx), a keystone species in North American
 forests. Methods We related remotely sensed maps of aspen presence with
 climate, topographic, and soil predictors to generate an ensemble SDM. We
 then incorporated locations of known populations, information on dispersal
 distances, and future habitat suitability to forecast areas likely to
 experience range retraction and expansion. Results Our ensemble SDM
 explained about 78 % of the variation in aspen occurrence. Relative to the
 1981-2010 period, we found average aspen habitat suitability across the
 SRME decreased by 8.4 % for the 2011-2040 period. We also found that large
 areas of the SRME may be suitable for aspen expansion, but that most of
 these areas are located more than 100 meters from existing aspen patches.
 Conclusions Our modeling suggests that climate change is likely to
 decrease habitat suitability for many aspen populations and that the
 potential expansion will be constrained by dispersal. However, artificial
 regeneration techniques could be used to facilitate range expansion.
 Moreover, our work highlights the potential for using remotely-sensed
 species occurrence datasets in SDMs to provide forest managers with more
 robust forecasts of how climate change may influence tree species
 distributions.
description: # Climate-driven decreases in aspen’s distribution and opportunities for
 future expansion across the Southern Rocky Mountains
 [https://doi.org/10.5061/dryad.t76hdr88v](https://doi.org/10.5061/dryad.t76hdr88v) ## Description of the project This archive contains predictions of habitat suitability for aspen across the Southern Rocky Mountain Ecoregion. Predictions are available for the historical period (1981-2010) and three future periods (2011-2040, 2041-2070, 2071-2100). Future predictions are available under two scenarios (i.e., Shared Socioeconomic Pathways; SSPs) generated under CMIP6, SSP2-4.5, and SSP5-8.5. SSP2-4.5 describes an intermediate scenario characterized by moderate increases in emissions through 2040, followed by a decline, while SSP5-8.5 describes a more extreme situation where emissions increase through 2100. ## Files ### Predictions.zip A zipped file containing the predictions of habitat suitability for aspen across the Southern Rocky Mountain Ecoregion. This compressed archive created using Archive Utility v. 10.15 on macOS Sequoia v. 15.01. The size of the compressed archived file is 561.9 MB. The uncompressed archive consists of 7 GeoTIFF files, each of which is a prediction of aspen habitat suitability based on a different climate change scenarios (X - historical, SSP2-4.5=SSP245, or SSP5-8.5=SSP585) and time periods (YYYY-YYYY). For example, the predicted habitat suitability for the 2011-2040 period under SSP2-4.5 is `predicted_SSP245_2011-2040-ensemble.tif`. File Details ### predicted_X_YYYY-YYYY-ensemble.tif dimensions: 9317, 5715, 1 (nrow, ncol, nlyr) resolution: 90, 90 (x, y) extent: 90170, 604520, 3901800, 4740330 (xmin, xmax, ymin, ymax) coord. ref. : WGS 84 / UTM zone 13N (EPSG:32613) names: suitability Habitat suitability values range from 0 (low) to 1 (high).