File:21st Century Temperature and Precipitation Scenarios.ogv

English: This data visualization from the NASA Center for Climate Simulation and NASA's Scientific Visualization Studio at Goddard Space Flight Center, Greenbelt, Md., shows how climate models used in the IPCC Fifth Assessment Report from the United Nations' Intergovernmental Panel on Climate Change (IPCC) estimate possible temperature and precipitation pattern changes throughout the 21st century.

The United Nations' Intergovernmental Panel on Climate Change publishes a report on the consensus view of climate change science about every five to seven years. The first findings of the IPCC's Fifth Assessment Report (AR5) were released on Sept. 27, 2013, in the form of the Summary for Policymakers report and a draft of IPCC Working Group 1's Physical Science Basis. The IPCC does not perform new science but instead authors a report that establishes the established understanding of the world's climate science community.

The report not only includes observations of the real world but also the results of climate model projections of how the Earth will respond as a system to rising greenhouse gas concentrations in the atmosphere. The IPCC's AR5 relies on the Coupled Model Intercomparison Project Phase 5 (CMIP5) effort, an international effort among the climate modeling community to coordinate climate change experiments.

This visualization represents the mean output of how a certain group of CMIP5 models responded to a scenario defined by the IPCC called Representative Concentration Pathways (RCPs). RCPs 8.5 represents potential worldwide greenhouse gas emissions and sequestration scenarios for the coming century. The pathways is numbered based on the expected Watts per square meter - essentially a measure of how much heat energy is being trapped by the climate system. The pathways is partly based on the ultimate concentrations of carbon dioxide and other greenhouse gases. The current carbon dioxide concentration in the atmosphere is around 400 parts per million, up from less than 300 parts per million at the end of the 19th century.

The carbon dioxide concentrations in the year 2100 for this RCP is 936 ppm.

This visualization represents the mean output of the RCP, because data from all models in the CMIP5 project was not available in the same format for visualization for all RCPs. The model compares a projection of temperatures and precipitation from 2006-2099 to a baseline historical average from 1971-2000.

Thus, the values shown for each year represent the departure for that year compared to the observed average global surface temperature from 1971-2000. The IPCC report used 1986-2005 as a baseline period, making its reported anomalies slightly different from those shown in this visualization.