Third mobile facility completes first year of data collection in northern Alaska

This fall, the AMF3 installation was completed with the addition of scanning and vertical-pointing radars, as well as a Raman lidar.
This fall, the AMF3 installation was completed with the addition of scanning and vertical-pointing radars, as well as a Raman lidar.
Another first of many to come for the North Slope site, the third mobile facility (AMF3) for the ARM Climate Research Facility completed 1 year of data collection at Oliktok Point, Alaska, on September 30, 2014, with 4 years remaining in this extended deployment as currently planned. Led by Sandia National Laboratories, data are being gathered by the AMF3 to better understand Arctic aerosol, cloud and radiative transfer processes that may play an important role in Arctic climate change. Data from the AMF3 will complement data collected since 1997 by ARM’s long-term site in Barrow, Alaska.

In September 2014, the Department of Energy Climate and Environmental Sciences Division, within the Office of Biological and Environmental Science, held a workshop focused on scientific priorities for observational and high resolution modeling activities in the North Slope of Alaska (NSA) region. The workshop was the second in a series focusing on key scientific needs, gaps, and priorities in linking ARM observational data to improved process model understanding and climate model prediction through the strategic deployment and operation of routine high-resolution modeling at the future ARM megasites at the NSA and Southern Great Plains (SGP). The AMF3 is expected to be an essential part of the North Slope megasite, although details are still under discussion with the ARM user community. The North Slope workshop report will be available in spring 2015.

"The workshop was an intense day and a half of brainstorming and information gathering," said Mark Ivey, NSA site manager from Sandia. "We feel it was a great success thanks to the efforts of participants and contributors who were willing to help us distill more than a dozen white papers to lists of essential science needs, gaps, and observations."

Expanding Measurements in a Challenging Environment

The challenging environment at Oliktok Point made itself known in December 2014 with snow drifts reaching the tops of the AMF3 shelters.
The challenging environment at Oliktok Point made itself known in December 2014 with snow drifts reaching the tops of the AMF3 shelters.
Phase two of the AMF3 installation was completed in October 2014 with the installation of scanning and vertically-pointed cloud radars and two Raman lidar shelters. With only a handful of Raman lidars (light detection and ranging capability) around the world, this unique instrument uses pulses of laser radiation to probe the atmosphere. A telescope collects the backscattered radiation that returns and the optics inside the laboratory shelter use that radiation to derive time- and altitude-resolved profiles of atmospheric water vapor, aerosols, clouds, and temperature. The system is housed in two standalone shelters; one serves as a laboratory enclosure, and the other contains support systems such as HVAC services and power conditioning.

Dedicated technicians stay with the AMF3—even during the severest of weather conditions.
Dedicated technicians stay with the AMF3—even during the severest of weather conditions.
A group of radars—the Ka-ARM Zenith Radar (KAZR), Ka-Scanning ARM Cloud Radar (KA-SACR) and W-Band Scanning ARM Cloud Radar (W-SACR), and Radar Wind Profiler (RWP)—were also installed at Oliktok this past year. The KAZR, KA-SACR, W-SACR, and RWP will provide the high-resolution cloud data needed to achieve megasite modeling goals.

"We operated our new radars at Oliktok successfully during the first winter following their installation during the summer of 2014, although we are facing big challenges with wind and drifting snow occurring this winter. We are looking forward to an innovative evaluation of the dual-frequency radar at Oliktok this spring." Ivey said.

In December 2014, the challenges of operating the AMF3 in the harsh arctic climate became a reality. The microturbines that generate electricity for the site were affected and power had to be supplemented with back diesel generators. The AMF3 shelters and exterior instruments iced over during phase 3 weather conditions—whiteout weather with visibility limited to feet or even inches. Low temperatures and high winds required staff to stay inside. Keeping the instruments warm and operating in these circumstances required extreme dedication by the two site technicians who stay at the site full time. Through their hard work and the arctic hardening of instrumentation, the AMF3 did not sustain irrevocable damage. The microturbines were fixed in January 2015 and full power was restored.

New Capabilities, New Uses

The team is preparing for the Evaluation of Routine Atmospheric Scientific Measurements using Unmanned Systems (ERASMUS), a two-week campaign at Oliktok Point in April 2015. This campaign serves two main purposes: to support the set of atmospheric measurements obtained concurrently by the third ARM Mobile Facility stationed at Oliktok Point; and to evaluate the potential for future routine unmanned aerial systems operations to gather atmospheric measurements at Oliktok Point. The campaign will improve understanding of the lower Arctic atmosphere, including aerosols and clouds, by providing vital data for analyses and model studies.

Also in 2015, the ARM Airborne Carbon Measurement (ACME) campaign moves to the North Slope of Alaska. The ARM Aerial Facility’s Gulfstream-159 (G-1) will be based out of Deadhorse, Alaska, near AMF3 at Oliktok Point. For three months in the summer of 2015, the G-1 will obtain measurements in this area to continue the study of atmospheric composition and carbon cycling.

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The ARM Climate Research Facility is a national scientific user facility funded through the U.S. Department of Energy's Office of Science. The ARM Facility is operated by nine Department of Energy national laboratories.