Screen capture from the National Climate Change Viewer

National Climate Change Viewer

Display maps, climographs, and histograms of projected change in temperature and precipitation from models in the CMIP5 experiment. Focus on any state, county, or hydrologic unit in the contiguous United States.
This tool offers historical (1950-2005) and future (2006-2099) climate and water balance projections derived from 20 downscaled CMIP5 climate models for the RCP4.5 and RCP8.5 scenarios. Updated in 2021, the newest version of the tool adds new measures of statistical significance and a plotting feature that lets users visualize underlying relationships between two selected variables and any number of the 20 climate models. 
The NCCV gives users a way to
  • visualize projected changes in climate (maximum and minimum air temperature, precipitation, vapor pressure deficit) and water balance (snow water equivalent, runoff, soil water storage, and evaporative deficit) for any state, county and USGS Hydrologic Units (HUC4 and HUC8) using a variety of graphics and tools.
  • view annual, seasonal, and monthly time series and averages for the historical period (1981-2010) and three future time periods (2025-2049, 2050-2074, and 2075-2099).
  • characterize climate change on maps, climographs (plots of monthly averages), histograms that show the distribution or spread of the model simulations, time series plots, and tables that summarize projected changes.
  • generate comprehensive, summary reports in PDF format and CSV files for the climate and water balance variables for each geographic area. Reports include national and regional maps for each variable and scenario
  • check the statistical significance of future changes for each region from the data table and model agreement charts.
  • export any chart in the NCCV in a range of graphic formats. Chart data can be exported in a compressed JSON format.

About the dataset

The NCCV displays the MACAv2-METDATA dataset, which is based on advanced methods of bias correction and downscaling. The MACAv2-METDATA dataset comprises results from 20 Global Climate Model on a 4 km by 4 km grid over the contiguous U.S.

Important Notice for Using Climate Projections

Climate projections can be useful for making decisions about the future, but the limitations of climate models make it easy to misinterpret or misuse their results. Be aware that:

  • Climate projections are not predictions. Projections are based on assumptions about future human emissions of greenhouse gases and other policy choices.
  • Climate projections do not attempt to predict the timing of meteorological events such as storms, droughts, or El NiƱos. The location and timing of future extreme weather events cannot be deduced from climate model projections.
  • Projections vary from model to model: the best projection dataset for one location and purpose may not be the best for other situations. Considering a range of projections may help you gain a more complete picture of potential future risks.
  • The increased spatial resolution of statistically downscaled projections available for temperature and precipitation may not be available for all parameters. In addition, increased resolution does not necessarily equate to greater fidelity or reliability.

For decisions involving the use of climate model projections, you may want to consider seeking expertise.

Last modified
26 May 2023 - 2:52pm