BLM REA CYR 2013 Near-term Future (2020s) Cliomes

Some of the CYR rasters intentionally do not align or have the same extent. These rasters were not snapped to a common raster per the authors' discretion. Please review selected rasters prior to use. These varying alignments are a result of the use of differing source data sets and all products derived from them. We recommend that users snap or align rasters as best suits their own projects. - This file includes a downscaled projection of decadal cliomes for the decades 2010-2019, 2020-2029, and 2060-2069 at 2km spatial resolution. It represents the projection for the A2 emissions scenario and the spatial extent is the Central Yukon REA study area. "Cliomes" can be considered to be assemblages of species and aggregated communities that might be expected to occur based on linkages with prevailing climate conditions. They are not the same as actual biomes, since actual species shift incorporates significant and variable lag times, as well as factors not directly linked to climate. However, results serve as indicators of potential change and/or stress to ecosystems, and can help guide in the management of areas of greatest and lowest resilience to changing climate. Input data used to calculate cliomes came from downscaled global climate projections created by Scenarios Network for Alaska and Arctic Planning (SNAP). Analysis of these data involved use of the Partitioning Around Medoids (PAM) clustering methodology, which defined regions of similar temperature and precipitation based on a Random Forests (Breiman, 2001) generated proximity matrix. Each cluster is defined by 24 input variables (monthly mean temperature and precipitation) and equates to one cliome, with a total of 18 identified. Further, the Random Forests algorithm was used to take the PAM classification and predict the spatial configuration of the cliomes given a changing climate. Alaska was modeled at the 2km resolution. Descriptions of the 18 cliomes are as follows: 1. The coldest, driest cliome particularly in summer and fall. Very harsh winters, very late springs, almost no summers, and very early falls. Sparsely vegetated tundra with up to 25% bare ground and ice, with an extremely short growing season. 2. Winters as cold as Cliome 1 (-31°C), but slightly more moderate in other seasons with a little more precipitation, although still very dry. Vegetated cold northern arctic tundra. 3. Similar to Cliome 2 in summer and fall, but more moderate winters and springs. Dry. More densely vegetated arctic tundra with up to 40% shrubs, but no tree cover. 4. Winter and fall similar to Cliome 3, but earlier springs and summers (8°C). Dry, despite slight increases in precipitation. Arctic tundra with denser vegetation and more shrub cover including some small trees. 5. Increased precipitation (243mm). Winters similar to coldest cliomes (1 and 2) but summer and fall similar to Cliome 4. Spring intermediate, most similar to Cliome 3. Dry, sparsely vegetated southern arctic tundra. 6. Warmer summer and fall conditions than any preceding cliomes with increased precipitation (272mm). Northern boreal/southern arctic shrubland, with an open canopy. 7. Winters similar to Cliomes 2, 3, and 5, but warmer spring, summer, and fall than all preceding cliomes. Still fairly dry. Northern boreal coniferous woodland, open canopy. 8. Markedly higher rainfall-equivalent (355mm) and much more temperate fall, winter, and spring temperatures. Dry boreal wooded grasslands - mixed coniferous forests and grasses. 9. Precipitation and summer/fall temperatures similar to Cliome 7, but warmer winters (-24°C) and springs. Mixed boreal forest. 10. Much milder winter, spring, and fall conditions and much higher precipitation than all preceding cliomes (561mm) with summers comparable to Cliome 8. Boreal forest with coastal influence and intermixed grass and tundra. 11. Temperatures similar to Cliomes 7 and 9 in summer (12°C). Intermediate between these two in winter and spring, but warmer than both in the fall, with higher precipitation, although drier than Cliome 10. Cold northern boreal forest. 12. Moderate precipitation similar to Cliome 11 (420mm), but warmer in all seasons. More densely forested closed-canopy boreal. 13. Cool falls and and summers similar to Cliome 5, but spring comparable to Cliome 11 (-7°C) and winter similar to Cliome 12. Relatively wet, like Cliome 10. Sparsely vegetated boreal with elevation influences. 14. Slightly warmer than Cliome 10 in all seasons, with even higher precipitation (857mm, the second highest of all 18 cliomes). Densely forested southern boreal. 15. Early springs, late falls, hot summers (16°C), and moderately cold winters. Moderate precipitation (474mm). Southern boreal/aspen parkland. 16. Moderately wet, with winters almost as cold as Cluster 13 (-20°C), but spring, fall, and summer almost as warm as Cluster 15. Southern boreal, mixed forest. 17. By far the wettest of all the clusters. Warmest winters of all clusters (-4°C), with warm spring and fall conditions and moderate summers similar to Clusters 8 and 10. Coastal rainforest, wet, more temperate. 18. The hottest of all clusters in spring, summer, and fall. Winters similar to Cluster 14. Moderate precipitation. Prairie and grasslands.