Operations Updates
ARM Climate Research Facility Operations Update - November 30, 2007
This bimonthly report provides a brief summary of significant accomplishments and activities in the operations area of the ARM Climate Research Facility (ACRF).
Interferometers Compared for ARM Mobile Facility Deployment in China
During the 2-week instrument comparison, the AERI planned for Linze was rolled outside of the SGP Guest Instrument Facility each day—weather permitting—to obtain its measurements. The SGP AERI took its measurements through a special window from inside the facility.
One instrument scientists use to obtain measurements important for climate studies is an atmospherically emitted radiance interferometer, or AERI. This sophisticated instrument measures the absolute infrared spectral radiance of the sky directly above the instrument. Two AERIs will be deployed with the ARM Mobile Facility in 2008 for a field campaign to study Aerosol Indirect Effects in China. One will be deployed at the primary ARM Mobile Facility site in Shouxian, and the other will be located with an ancillary facility to the northeast, at Linze. For 2 weeks in mid-November, the AERI planned for Linze operated continuously next to the AERI at the ACRF Southern Great Plains (SGP) site for calibration and comparison purposes prior to deployment in China. This comparison will ensure that AERI data obtained at the northern and southern locations are comparable and allow scientists to quantify regional differences in aerosol, cloud, and atmospheric properties.
As part of the AMF baseline instrument suite, an AERI is currently deployed in Germany for the Convective and Orographically Induced Precipitation Study. At the conclusion of that campaign in December, the AMF will be packed up and shipped to China for its 9-month deployment at Shouxian beginning in March 2008. Meanwhile, the second AERI and other ancillary facility instruments are scheduled to begin operating at Linze in February for 4 months, then move west to Xianghe for 4 more months of operation. Both AERIs will provide important data about the microphysical, optical, and radiative properties of Asian dust aerosols, which in turn will assist scientists in studying the long-range transport of heavy dust and pollution from East Asia over the Pacific Ocean and North America.
High-Speed Internet Deflects Information Overload
Covering approximately 143,000 square kilometers in Oklahoma and Kansas, instruments at the various facilities throughout the SGP site generate approximately 27 gigabytes of data every day. Click for a larger image.
A little more room in the internet link at the ACRF Southern Great Plains site is providing needed relief to the crowded lines that keep data flowing from the site. In July 2007, the internet service from the SGP Central Facility was switched to a higher speed (6 megabits) link, increasing the bandwidth by almost four times and providing a significant cost savings. In addition, a number of SGP extended facilities, boundary facilities, and intermediate facilities have been converted from dial-up connections to digital subscriber lines to improve both bandwidth and reliability.
Established in 1992, the SGP site remains the flagship ACRF site, with the most instruments and the longest data record. Continued increases in data flowing through the SGP Central Facility began approaching the critical limits of the original bandwidth. Recognizing the need for faster data transfer to keep the lines from bogging down, ACRF operations staff pursued new internet services for this critical component of the site data system. Cost savings was achieved by moving from an offsite T1 connection to a local internet provider. The physical length of the original T1 service line contributed significantly to its higher cost.
Internet access to and from the site was disrupted for only a few hours as the new routing mechanism propagated through the internet; a small price to pay for a smooth-running infrastructure. Infrastructure at the SGP Central Facility will now support a 20-megabits link, if needed, for future instrument enhancements. Operations personnel continue to monitor the availability of more cost efficient network connectivity for those extended and intermediate facilities still on dial-up links.
