Field Campaigns

Now accepting proposals for use of the ACRF sites, mobile facilities, and AVP in FY2011

Annual Meeting

Plan to attend the 2009 Science Team Meeting; register today!

Events

Program highlights at American Meteorological Society Annual Meeting

Update

Scout team surveys Storm Peak area

Publications

October Workshop Report on ACRF's role in solving climate science issues available

Research Spotlight

Second Version of Long-Term Climate Modeling Best Estimate Data Released

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. A summary of all the changes in version 2 can be found on the CMBE web page.

To access these data, log in to the Data Archive. To request an account, go here. (Please contact the Archive if you have any login questions.)

Research Spotlight

Revised Convective Triggering Mechanism Improves Precipitation Forecast

An improved convective triggering mechanism developed by ARM scientists based on ARM observations was implemented recently in the Global Spectral Model at the Japan Meteorological Agency (JMA) to improve surface precipitation forecasts. The revised triggering mechanism uses a dynamic convective available potential energy generation rate (DCAPE) to control the onset of deep convection. It assumes that deep convection occurs only when the large-scale dynamic forcing makes a positive contribution to the existing positive CAPE, i.e., DCAPE >0. This simple dynamic constraint emulates the collective effects of lower-level moistening and upward motion of the large-scale circulation.

With the new triggering mechanism, the revised JMA's Global Spectral Model with T959 truncation and 60 vertical levels (T959L60DCP) substantially reduced the precipitation bias in the original Global Spectral Model (T959L60).

For more information, read the research highlight.

Research Spotlight

Black Forest, Germany, WACR- ARSCL Evaluation Products Now Available

Observations from the 95 GHz W-band ARM Cloud Radar (WACR), Micropulse Lidar, and ceilometer have been combined using the new WACR-Active Remote Sensing of Clouds (WACR-ARSCL) value-added process (VAP) (Kollias and Miller, 2007) to produce cloud boundaries and time-height profiles of cloud location, radar moments, and linear depolarization ratio fields for the ARM Mobile Facility deployment in Heselbach, Germany (3/29/2007 – 1/2/2008). The basic algorithm used in the WACR-ARSCL VAP is similar to that employed by the ARSCL VAP, which is based on 35-GHz Millimeter Cloud Radar observations (Clothiaux et al., 2000).

These data are available as an ARM evaluation product from the ACRF Data Archive. Please contact the Archive if you have any login questions.