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These
include the
Southern Great Plains
site in north-central Oklahoma, the
North Slope of Alaska
with a site near Barrow, and the
Tropical Western Pacific
with sites on Manus and Nauru Islands. Eventually, we will
display cloud property imagery from all these sites.
As ARM science team members and active participants of the cloud working group, we are charged with conducting research that has, as its ultimate goal, the improvement of cloud and radiation parameterization in global climate models. Specifically, we and several other groups are examining the data record being generated by the ARM program and are attempting to extract information from that record that will further our scientific understanding of the role clouds play in the global climate. In time, this improved understanding will foster development of improved representations of cloud in global climate models.
The data we use in this endeavor is quite varied and includes surface-based active and passive remote sensors, radiosonde data and observations collected in situ by research aircraft. More detailed information regarding the operational ARM instruments can be found on the ARM instrumentation WWW sites. The cornerstone instruments used for cloud research at the ARM sites consists of the Millimeter Cloud Radar, the micropulse lidar and the Raman lidar. Our own research centers around use of MMCR data augmented by other data including the Atmospheric Emission Radiance Interferometer, microwave radiometer and laser ceilometers.
The MMCR is a Doppler radar that operates in the Ka frequency band (~8 mm wavelength). The radar points vertically and probes cloud layers as they pass overhead. The MMCR was developed by scientists at the NOAA Environmental Technology Laboratory in Boulder, CO with Dr. Ken Moran as Chief Engineer. Unlike research grade radars operated by several university groups and government labs, the MMCR operates continuously and demonstrates unparalleled sensitivity and versatility in probing non-precipitating cloud systems. Much of the initial data processing system was expertly designed by Dr. Eugene Clothiaux, a senior member of the Penn State University atmospheric radiation group headed by Dr. Thomas Ackerman. We utilize the end products of this processing in much of our research work.
In order to document cloud properties suitable for the eventual improvement of cloud parameterization in climate models, we examine a wide range of specific quantities ranging from simple frequency distributions of cloud occurrence to the derived microphysical properties of cloud layers and individual resolution volumes. Production of all these products require some degree of processing. Our methodology is based on a growing suite of algorithms that perform various tasks such as sorting the data, deciding what data are available, when certain cloud and meteorological conditions are satisfied and when other higher order processing can be initiated. The higher order schemes typically combine various data streams, apply theoretical approaches to the data, and generate output graphics and data files. The output of files and graphics can be found in the daily archive below. Statistics are then generated from the individual days. We will eventually make monthly, seasonal, and annual statistics available on this site. Presently, only a subset of the monthly statistics are accessible.
This archive is intended to evolve as our ability to generate output products improves over the coming months and years. As with any research operation, our schedule is quite fluid and is dictated by how fast we can generate computer code and come up with new ideas. Therefore, if you do not see a specific product you think would be useful, either wait for us to catch up with your needs or contact us by email (mace@atmos.met.utah.edu) or by phone (Jay Mace- 801-585-9489). We are very interested in comments and criticisms as to how this archive can best suit the needs of those conducting global change research. So, don't be shy about sending us your thoughts. Also, if you have generated products you think would be useful for inclusion in this archive, we are more than happy to post them here giving credit where it is due, of course.
A detailed description of what products are available on this site
can be found elsewhere: