Climate Models Need Closure Too

 
Published: 28 February 2009
These radiometers at the Southern Great Plains site match those on the aircraft for the RACORO field campaign. They will operate there for the duration of the campaign. The radiometers will take measurments continuously throughout the campaign, allowing scientists to compare measurements from the aircraft against those collected routinely by radiometers at the site.
These radiometers at the Southern Great Plains site match those on the aircraft for the RACORO field campaign. The radiometers will take measurements continuously throughout the campaign, allowing scientists to compare measurements from the aircraft against those collected routinely by radiometers at the site.

In late January, scientists initiated a five-month field campaign involving routine flights above the ARM Southern Great Plains (SGP) site. The airborne observations from RACORO will, among other things, be used to test and refine capabilities for sensing the atmosphere from the surface. To help validate and tie in the aircraft measurements to the SGP ground measurements, scientists involved in a related field campaign, called Surface Radiation Comparison Transfer Measurements, are deploying a set of the aircraft-style radiometers at the SGP Central Facility for the duration of the campaign.

An important aspect of RACORO is radiative “closure” experiments, or studies to “close the gap” between actual measurements of solar and terrestrial radiation and the associated calculations produced by models. Therefore, accurate radiation measurements are critical. However, the radiometers onboard the RACORO aircraft are of different make and manufacture than those ARM deploys at its surface sites, and were additionally modified for aircraft use. Measurements from the surface-based aircraft-style radiometers will be directly compared to the aircraft-mounted radiometers before, during and after the RACORO campaign. This comparison will provide a means of relating the possibly differing performance and characteristics of both the airborne and surface radiation measurements. As a result, the measurements will be better linked to enhance their usefulness in future radiative closure efforts.