Version 2 of the Climate Modeling Best Estimate includes the data source information for cloud fraction, as depicted in this data plot. (Larger image.)

With major improvements in the cloud fraction, cloud liquid water path (LWP), precipitable water vapor (PWV), and surface radiative fluxes, a new version of the “Climate Modeling Best Estimate” (CMBE) is now available from the ARM Climate Research Facility (ACRF) Archive. This data set, specifically tailored for use in evaluating global climate models, includes long-term best estimates from 11 selected ACRF measurements and now encompasses data from the ACRF sites in Barrow, Alaska; Nauru Island; Manus Island, Papua New Guinea; and Darwin, Australia; and the Southern Great Plains (SGP) site in Lamont, Oklahoma.

Recent improvements to input datastreams for the CMBE—Microwave Radiometer (MWR) Retrievals (MWRRET) Principal Investigator Data Product and Data Quality Assessment for ARM Radiation Data (QCRAD) Value-Added Product (VAP)—were used in this revision. As a result, LWP and PWV data from the SGP site were reprocessed using the MWRRET algorithm, which resulted in considerable changes in these fields. The surface radiative fluxes at the Manus Island and Darwin sites were revised using the QCRAD data. In addition, a new quality control flag indicates whether the best estimate of cloud fraction is determined by both Millimeter Wavelength Cloud Radar (MMCR) and Micropulse Lidar (MPL) or just one of the instruments.

For a complete summary of all the changes in version 2, see the CMBE web page. To access these data, log in to the Data Archive. (Go here to request an account.)