AMF Science

Locale: Anywhere in the World!

The purpose of an ARM Mobile Facility (AMF) is to collect essential information about the cloudy and clear atmospheres in climatically important regions that are under sampled at present. In some of these regions, even the macroscopic cloud structure is relatively unknown. An AMF will produce a datastream that will be used by the atmospheric community to test and improve parameterizations in global climate models. The data from the AMF instruments will be processed using specialized routines that will produce cloud and clear sky data products specifically designed to address the scientific issues in a particular climatic region.

The ARM science community has put forth numerous ideas on what science issues could be addressed by a mobile facility. The ARM Science Board will decide what specific science is to be addressed by an AMF deployment and a science plan will be written accordingly. The AMFs are designed to collaborate with experiments (especially aircraft) from other agencies. For AMF1, the ability to host instruments other than the baseline set of instruments is a key requirement. For AMF2, the ability to obtain measurements in a marine environment is a key priority. To learn more about using an AMF, see the Submitting Proposals page.

These mobile laboratories have been designed to collect climate-related data from under sampled regions and typical deployments range from six to twelve months. Active remote sensors are used to characterize the location and evolution of the cloud, aerosol, and thermodynamic profiles above the deployment location. Cloud radar is used to determine cloud location, reflectivity, particle vertical velocity, and velocity distribution above the facility. Aerosol structure in the subcloud layer and optical cloud base height is measured with a Micropulse Lidar and laser ceilometer. Data from radiosondes and two Microwave Radiometers are used to quantify the vertical thermodynamic structure and to measure the precipitable liquid water and water vapor. A boundary layer wind profiler continuously measures the wind profile and refractive index structure above the site.

A full complement of radiometers is used to measure upwelling and downwelling radiation. The surface latent, sensible, and CO2 fluxes are measured, along with standard surface meteorological variables.

AMF1 is also equipped with instrumentation that enables research on aerosol-cloud relationships. Measurements of light absorption by aerosols and cloud nucleating properties are made routinely. By separating cloud and aerosol particles, the following scientific questions can be addressed depending on the instrumentation used in a particular deployment:

  • What are the differences in chemistry between interstitial and activated aerosol?
  • What role do organics play in aerosol formation and activation?
  • How do clouds change the optical properties of the aerosol?
  • How do the CCN spectra differ between interstitial and activated aerosol?

Aircraft and satellite data have been used to quantify spatial variability in the vicinity of past and present AMF deployments. These aircraft have been equipped with a variety of probes that coincide and complement AMF measurements.