AR5 Climate Simulations

The NCAR GIS Program provides access to climate change projections that have been generated for the 5th Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC) by the Community Climate System Model (CCSM-4).  

 

Statistically downscaled (4,5km) monthly means for Total Precipitation and Air Temperature.

Total Precipitation and Air Temperature monthly means ( individual ensemble members as well as ensemble averages) of historical (1850-2005) and future (2006-2100) emissions scenario.

 

Statistically downscaled (4.5km) 20-year monthly and annual averages for Total Precipitation Anomalies and Air Temperature Anomalies.

20-year monthly and annual average for Total Precipitation Anomaly and Air Temperature Anomaly, (ensemble averages) for future emissions scenarios.

 

Global (1 degree) monthly means 

 Monthly mean (ensemble members and ensemble averages) for a number of 2D variables for historical and future emissions scenarios. A list of of the variables we have available.

 

Global (1 degree)  20- year monthly and annual averages for Total PrecipitationAir Temperature Total Precipitation Anomaly and Temperature Anomaly

20-year monthly and annual average for Total Precipitation (ppt), Total Precipitation Anomalies (appt), Air Temperature (tas), and Air Temperature Anomalies (atas) for future emissions scenarios.

 

Data Access

Data can be assessed from our THREDDS data server as WMS, WCS, OPeNDAP, or through a netCDF sub selector. 

 

Filename structure

<variable>_<atmospheric component>_<model>_<RCP emission scenario>_<ensemble member>_<date range available>

tas_Amon_CCSM4_rcp45_r5i1p1_200601_210012.nc 


Variables available

ppt - Total Precipitation (mm/year)

tas - Air Temperature (degrees Celsius) 

appt20y – 20-year annual average for Total Precipitation Anomaly (mm/year)

appt240m – 20-year monthly average for Total Precipitation Anomaly (mm/year)

atas20y - 20-year annual average for Temperature Anomaly (degree Celsius)

atas240m – 20-year monthly average for Temperature Anomaly (degree Celsius)

 

Emission Scenario

Representative Concentration Pathways (RCPs) provide concentrations of atmospheric greenhouse gases (GHG) and the trajectory that is taken over time to reach those concentrations. These RCPs are named according to the level of radiative forcing (enhanced greenhouse effect or warming) that they produce by the year 2100

RCP 2.6 – 2.6 Watts per square meter (Wm-2) by 2100

RCP 4.5 – 4.5 Watts per square meter (Wm-2) by 2100

RCP 6.0 – 6.0 Watts per square meter (Wm-2) by 2100

RCP 8.5 – 8.5 Watts per square meter (Wm-2) by 2100

 

Ensemble members

Individual ensemble members (rXi1p1) and ensemble member average, minimum, and maximum (ensave).  Where X idicates the ensemble member and ensave is the average of all ensemble members.

 

Years

Data with 20y or 240m in the variable name are 20-year averages. 

The date stamp for the annual climate simulations is the middle year in the 20-year average. For example if you download data for the year 2050 you are actually getting the average from 2040-2059.

 

The date stamp for the monthly climate simulations is the beginning year in the 20-year average. For example if you download data for the year 2050 you are actually getting the average from 2050-2069.