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EnviroAtlas

Changes over Time

Understanding how and why our environment is changing over time is an important element to ensuring our ability to mitigate and adapt to those changes.  Understanding the potential impact of change helps us decide how to manage our resources in a way that ensures our natural environment can continue to provide the goods and services on which we as a society depend.  To this end, EnviroAtlas provides past and future projections for a subset of variables to investigate historical change and project future change.   

What We Provide

Climate Projections out to 2099 & Historical Climate Data 1950 - 2005 

The NASA Earth Exchange (NEX) scientific collaboration platform has made available downscaled CMIP5 climate projections for the conterminous United States with a spatial grid resolution of 800 meters.  The EnviroAtlas team has converted these large complex files into a geospatial format and has made them available through two tools in the EnviroAtlas Interactive Map.  

Variables  

  • Minimum temperature
  • Maximum temperature
  • Precipitation
  • Potential Evapotranspiration 

Seasons

  • Fall
  • Winter
  • Spring 
  • Fall 
  • All seasons - annual

Representation Concentration Pathways

The Intergovernmental Panel on Climate Change (IPCC) has periodically created climate change scenarios to explore future developments in the global environment with special reference to the production of GHGs and aerosol emissions. These scenarios can be used to make projections about future climate and to understand potential vulnerabilities to climate change. The Representation Concentration Pathways (RCP) used in this work were released in 2014.

RCP 2.6 – This scenario is characterized as having very low greenhouse gas concentration levels. It is a “peak-and-decline” scenario and assumes that GHGs are reduced substantially over time. This is the most benign climate scenario of the four.

RCP 4.5 – This scenario assumes a stabilization will occur shortly after 2100, and assumes less emissions than RCP 6.0, which is also a stabilization scenario.

RCP 6.0 – This is a stabilization scenario in which the increase in GHG emissions stabilizes shortly after 2100 through the application of a range of technologies and strategies for reducing GHG emissions.

RCP 8.5 – This scenario is characterized by increasing GHG emissions over time, and factors in the highest GHG concentration levels of all the scenarios by 2100.

Historical climate – The ensemble average for each RCP model historical run were included. This data is provided for the years 1950-2005.