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Energy Department Dedicates Global Climate Change Research Facility

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November 18, 1992 Share This!

RICHLAND, Wash. — The Department of Energy today dedicated the Cloud and Radiation Testbed (CART), a scientific facility in the Kansas-Oklahoma border region intended to achieve greater certainty in the analysis, determination and prediction of global climate change.

The facility, part of the department's Atmospheric Radiation Measurement (ARM) program, is the first of five planned around the world. It consists of up to 39 small (50 to 160 acres) arrays of weather and climate instruments spread across a 50,000 square mile area in north central Oklahoma and south central Kansas. Four more facilities, planned for the tropical western Pacific Ocean, the North Slope of Alaska, the eastern North Pacific or Atlantic Oceans and the Gulf Stream off the coast of North Carolina, will complete the monitoring network.

During the next seven to 10 years, the remote-sensing instruments at each array in the Cloud and Radiation Testbed will collect and analyze data that will help determine the effects of sunlight, radiated energy and clouds on temperatures, weather and climate.

William Happer, Director of the department's Office of Energy Research, in remarks at the dedication ceremony said, "The ARM program is our highest priority global change research project because it addresses some of the great uncertainties about greenhouse gases and their potential impact on global climate."

One of the greatest scientific uncertainties in climate change prediction is the role of clouds. Different types of clouds contribute to either warming or cooling the atmosphere. In addition, as climate changes, clouds may well change, enhancing or modifying the climate change through a process called the cloud-radiative feedback. While this feedback is of fundamental importance in predicting future climates, it is poorly understood.

The computer models (called General Circulation Models or GCMs) used to predict climate change treat clouds and this feedback simplistically. Knowledge gained through the ARM program will contribute to a better understanding of potential climate changes by improving the GCMs. (The term "radiation" in the ARM program title refers to both sunshine and energy radiated back into space).

The first CART site is the only one planned for the continental U.S. The Southern Great Plains was chosen because of its important climate, atmospheric and land characteristics. A wide variety of cloud types, temperature and humidity exist in the area, providing an excellent test for the GCMs. Additionally, seasonal changes in the area provide a wide spread of surface cover, ranging from bare earth to mature crops, and a full range of moisture conditions. Relatively smooth terrain assure consistency in measurements.

The addition of the ARM instruments to existing National Weather Service facilities and a network of weather instruments funded by the state of Oklahoma will make this the most heavily instrumented region for atmospheric research in the world.

The CART site covers a rectangle, 250 miles by 200 miles, that is similar in size to the individual surface areas, "grid cells," in state of the art GCMs. The models are normally constructed with data collected over relatively short periods of time--usually several weeks or months, raising questions about whether model inputs are truly representative. The ARM program is unprecedented because it will collect data for almost a decade.

The overall result of Atmospheric Radiation Measurement program's efforts will improve scientists' ability to predict how much the Earth's climate might change, how fast that change could occur and what the regional effects of that change might be--information needed by national and world leaders to make important energy and economic policy decisions.

The program is notable in several other ways:


  • ARM scientists are using the latest in laser, radar and other remote-sensing technologies, including lidar, a technology developed at the Los Alamos National Laboratory and currently being used in a joint DOE/Mexico project to investigate and improve air quality in the Mexico City area. In some cases, instruments have been designed specifically to ARM specifications, pushing them to their next generation. One primary example is the use of Radio Acoustic Sounding Systems (RASS), coupled with the latest radar wind profilers to gain additional information on virtual temperature at various altitudes. (See enclosed sheet for detailed descriptions of instruments and the types of data to be collected).
  • The ARM program plans call for the use of small satellites and the newest generation of remotely piloted vehicles. The vehicles can be used to gather data for extended periods at heights of more than 50,000 feet.
  • The ARM program is one of the largest and most successful collaborative efforts involving DOE laboratories. Eighteen universities and several other federal agencies are also taking part in this unique partnership (see attached list). The science team alone numbers more than 300.


The Argonne National Laboratory manages the Southern Great Plains site for the Department of Energy. Today's dedication ceremony was held at the CART central facility--the point at which the CART site's data is collected. There more than 100 instruments ultimately will be arrayed across 160 acres of cattle pasture almost two miles from the nearest residence. The pasture is one of many dotted between the wheat fields of rural Grant County, Oklahoma.

Dr. Happer dedicated the site to the memory of the late atmospheric scientist, Frederick M. Luther (1943-1986). Luther was instrumental in involving more than 60 researchers in an international effort to evaluate and improve the solar and longwave calculations used in climate models. This effort resulted in the recommendation that a dedicated field measurement program be begun to evaluate the performance of climate models. The ARM program was developed in response to that recommendation.

For 14 years, Luther was a member of Lawrence Livermore National Laboratory's Atmospheric and Geophysical Sciences Division; he became associate division leader in 1979.

DOE's ARM program is part of the interagency U.S. Global Change Research Program.

Tags: Environment, Fundamental Science, Operations, Climate Science, Atmospheric Science, Aerosols, Facilities

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