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Research Spotlight
Data Available for Aerosol Indirect Effects Study in China
Data collected by the ARM Mobile Facility in Shouxian during the Aerosol Indirect Effects Study in China from May through December 2008 are now in the Data Archive. Extensive measurements of clouds, aerosols, radiation, and precipitation will help scientists to examine the role of aerosols in affecting the regional climate and atmospheric circulation.
To check availability, visit the instrument and data plot page. To order the data, go to the ACRF Data Archive.
Please contact the Archive if you have any login questions.
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.
Mobile Facility Begins Marine Cloud Study in the Azores
Today marks the beginning of the 20-month Clouds, Aerosol and Precipitation in the Marine Boundary Layer field campaign in the Azores to study the seasonal life cycle of marine clouds and how they modulate the global climate system. Data obtained by the ARM Mobile Facility on Graciosa Island will provide a long-term record of seasonal statistics needed to improve climate models.
See ARM News Center story
Atmospheric Radiation Measurement Program
The Atmospheric Radiation Measurement (ARM) Program is the largest global change research program supported by the U.S. Department of Energy. The primary goal of the ARM Program is to improve the treatment of cloud and radiation physics in global climate models in order to improve the climate simulation capabilities of these models.
To achieve this goal, ARM scientists and researchers around the world use continuous data obtained through the ARM Climate Research Facility. This scientific user facility provides a unique asset for interdisciplinary global change research among the national and international scientific community.
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