Farrell racks up frequent flyer mileage thru IceBridge

The flight is eight hours long.

The plane is no commercial airliner; there are limited seats, lots of equipment. The flight can get quite noisy, and passengers often wear headsets to talk to each other. They also wear thermal clothing and bring their own food.

“There’s certainly no in-flight service,” joked ESSIC Assistant Research Scientist, Dr. Sinead Farrell.

Cruising at 1,200 feet above miles of sea ice is just another routine flight for Farrell and other researchers of NASA’s Operation IceBridge team.

Initiated in 2009 after the ICESat polar observations satellite stopped collecting data, the mission for IceBridge seeks to study the features and behavior of both ice sheets and floating sea ice in the Arctic and Antarctic oceans, as well as to assess how Polar Regions interact with global climate systems.

“IceBridge … was designed to literally bridge the gap between the NASA ICESat and ICESat-2 satellites,” Jackie Richter-Menge, the leader for the IceBridge sea ice science team, said. ICESat-2 will acquire more detailed and more frequent measurements than its predecessor.

To accomplish its mission, IceBridge operates out of three bases: Kangerlussuaq, Greenland, Thule, Greenland, and Fairbanks, Alaska. According to Farrell, researchers conduct sea ice expeditions from the latter two locations, which when combined, offer surveillance across nearly 50 percent of the Arctic Ocean.

The researchers employ a wide range of airborne instruments to collect data; Laser altimeters that measure the elevation of the ice, snow radars, and cameras capturing high-resolution digital imagery are just a few examples.

Also new to IceBridge’s 2014 campaign is a device that collects data on the albedo or light reflection of the sea ice.

As the ice surface melts in summer, it forms dark pools. The darker parts of a sea ice floe absorb more light energy and consequently become warmer, not unlike how a black car becomes warmer than a white car while sitting in the summer sun. As these darker parts increase in temperature, the ice surrounding them begins to melt.

This series of events forms the albedo feedback system, which according to Farrell, researchers have been monitoring to determine trends in the polar melting season.

“One big discovery over the past decade is that the melt season is [getting] longer,” Farrell said.

In a 2014 NASA and National Snow and Ice Data Center (NSIDC) study, researchers found melt seasons spanned an average of five days longer per decade between 1979 and 2013.

Beyond the lengthening summer melt season, IceBridge helps determine which Polar Regions are the most vulnerable to climate change. As an example, Farrell noted that IceBridge measurements collected in the Beaufort Sea near Alaska reveal a decline in ice thickness and stability compared to sea ice north of Greenland.

Longevity is another key factor researchers utilize to determine both regional stability and the health of its sea ice. As ice ages, it thickens and becomes more resilient to melting. Older ice is also less flat, which may make it harder for melting pools to spread across its surface.

While the length of the melt season is growing, the longevity of the Arctic sea ice pack is diminishing. Despite increases between 2013 and 2014, only 43 percent of Arctic Ocean ice is more than one year old and just 7 percent is more than five years old, according to the NSIDC.

IceBridge has collected data on snow depths, ice thickness and ice age, but not without overcoming hurdles. Like many government-funded science endeavors, IceBridge has suffered from increasing budget cuts.

“The primary obstacle is adequate funding to support the mission and, importantly, the research projects that look to use IceBridge data,” Richter-Menge said.

IceBridge scientists also must deal with problems innate to working in the Arctic, such as sharing field space with researchers from other universities, countries and government agencies or coping with storms.

“Our biggest [challenge] is the weather,” Farrell said. “We can only fly on good weather days. [We need] good weather at the airfield, and good weather over the survey location.”

Fortunately for IceBridge’s spring campaign, it was able to survey on 12 of its 13 initial flight days. And with the project nearing completion, researchers are hoping for such luck to continue, as further data collection and a foray into conducting summertime flights are on the horizon for late summer 2014.

“We’re going to try and fly in the summer time … [which we’re] really looking forward to,” Farrell said. “That’s going to bring us lots of new information, particularly on the impact of surface melt ponds on the health of the sea ice pack.”