Cloud Feedbacks



Other MIPs



Google Calendar

Lab Calendar

Site Map


Privacy & Legal Notice

Thanks to Our Sponsors:

PCMDI > WCRP CMIP3 Model Output > Diagnostic Subprojects Printer Friendly Version
<< Back to WCRP CMIP3 Subprojects

Evaluation of climate model simulations of the US Climate Extremes Index and the US Greenhouse Climate Response Index

PI: David Karoly
Institution: University of Oklahoma
Additional Investigators: Aaron Ruppert, Melissa Bukovsky, David Easterling, Jay Lawrimore
Karl et al. (1996) developed two indices to quantify observed changes in climate within the contiguous United States, a US Climate Extremes Index (CEI) and a US Greenhouse Climate Response Index (GCRI). The CEI was based on a combination of climate extreme indicators, while the GCRI was a combination of indicators based on projected changes due to greenhouse climate change. These indices integrate changes in climate over several different temperature and precipitation measures and are likely to provide early detection of important changes in climate in the United States. Karl et al. (1996) noted an increasing trend in the CEI in recent decades and a significant positive trend in the GCRI during the 20th century. However, attribution of these observed changes to specific causes was not possible as they were not directly compared with climate model simulations.

This project has been funded by NOAA OGP CCDD to update the observed CEI and GCRI and to compare them with model simulations. Daily and monthly climate model data for the US region from simulations with several different climate models, including those from NCAR, GFDL, the Hadley Centre and the Canadian Center for Climate Modeling and Analysis, will be collected and analyzed. The interannual and decadal variability of the components of the indices from the model data will be compared with those from observations to assess the quality of the model simulations. Forced climate model simulations of 20th century climate variations will be analyzed. These will include simulations with changes in greenhouse gases, aerosols, and land use (anthropogenic forcing). The observed changes in the indices will be compared with the forced model simulations to assess the likely causes of the observed changes.

The analysis will make use of both daily data and monthly mean data for the US region from both control model simulations and forced simulations for the 20th century. A graduate student, Aaron Ruppert, is already working on this project.

Karl, T.R., R.W. Knight, D.R. Easterling, and R.G. Quayle, 1996: Indices of climate change for the United States. Bull. Am. Meteor. Soc., 77, 279-292.

    Add Publication

    << Back to WCRP CMIP3 Subprojects
    For questions or comments regarding this website, please contact the Webmaster.
    Lawrence Livermore National Laboratory  |  Physical & Life Sciences Directorate