Atmospheric Radiation Measurement Climate Research Facility US Department of Energy

Southern Great Plains


The Southern Great Plains (SGP) atmospheric observatory was the first field measurement site established by the ARM Climate Research Facility. This observatory, also known as a megasite, is the world’s largest and most extensive climate research facility.

Scientists use data from the SGP to learn about cloud, aerosol, and atmospheric processes, which in turn leads to improvements in models of the Earth’s climate.

Laboratory Without Walls

The SGP observatory consists of in situ and remote-sensing instrument clusters arrayed across approximately 9,000 square miles in north-central Oklahoma and south Kansas.

Located on 160 acres of cattle pasture and wheat fields, the heart of the SGP observatory is the heavily instrumented Central Facility southeast of Lamont, Oklahoma. Technicians, along with support staff and observers, monitor data from the Central Facility instruments and from smaller, unstaffed facilities throughout the site.

The SGP site offers high-quality data and simulations for atmospheric scientists to use. Data are used in a variety of ways from single observation analyses, to multi-observation process studies, to assimilation into Earth system models.

Instruments and Data

The ARM Facility has placed more than 50 instrument platforms or suites at the SGP observatory, including:

  • Radiometers
  • Radars
  • Lidars
  • Surface meteorological instrumentation
  • Aerosol instrumentation
  • Total sky imager
  • Ceilometer
  • Radiosondes

Explore SGP Instruments

Researchers supplement the continuous observations with guest instruments during field research campaigns or by requesting increases in the frequency of measurements, such as sonde launches.

The ARM Facility transmits all data gathered at the SGP to the ARM Data Center and they are made freely available via Data Discovery.

Modeling Capabilities

In addition to taking measurements, the ARM Facility recently began building data sets that can be incorporated into atmospheric models. These data are used in large-eddy simulation (LES) models, which simulate atmospheric air currents and cloud processes, to provide context and a self-consistent representation of the atmosphere surrounding the SGP.

The LES ARM Symbiotic Simulation and Observation (LASSO) workflow is the pilot project developing a framework to offer modeling capabilities alongside instrument data.