ROBERT C. BALLING, JR. and Contributing Editor RANDY CERVENY are climatologists at Arizona State University.
E ight downed World War II planes trapped under the ice in Greenland . . . a massive recovery effort to return them to the surface . . . and global climate change. Three apparently very different stories, yet they are all tied together in an unusual climate puzzle involving the fate of the Lost Squadron.
At the height of World War II, eight brand-new airplanes--two B-17 Flying Fortresses and six P-38 Lightnings--were flying to Iceland, headed for the war in Europe. On July 15, 1942, due to deteriorating weather conditions, the pilots were forced to ditch their warplanes in a never-before-attempted landing on Greenland's frozen icecap. After eight dangerous but successful landings and a harrowing rescue of the crew across the ice, the warplanes were abandoned to the whims of Greenland's weather. [Read about the rescue of the lost squadron crew.]
Dreams of Recovery
For the next 40 years, aviators and adventurers dreamed of recovering the eight planes, dubbed the "Lost Squadron." Initially, recovery was thought to be a fairly straightforward operation: Simply locate the planes under the snow and ice, dig a little, and pull them out. As one of the initial searchers remarked, "The planes are still there. All we have to do is shovel the snow and fly 'em into the sunset!"
Of course, the biggest unknown was the amount of ice covering the planes. Since that ice is directly related to how much snow falls, the question "How much snow had fallen over the area in 40 years?" was raised. Early on, the two leading aviation buffs and adventurers searching for the Lost Squadron, Pat Epps and Richard Taylor, had estimated that the planes would be only 40 feet below the surface.
Their estimates were based on three factors. First, even though continental ice sheets like those in Greenland and Antarctica are covered with ice and snow, these frozen lands are deserts--very little precipitation falls there. For example, although the Greenland ice sheet is nearly 10,000 feet thick at its summit, that ice took an extraordinarily long time--over 250,000 years--to accumulate.
Second, study of near-surface ice lenses suggested that comparatively little ice would have accumulated from 1942 to 1982. These lenses are sheets of ice that form part of the layered sequence of snow and ice found in glaciers. Each layer generally consists of an amount of snow accumulated during the winter underneath an ice lens of melted, then refrozen, water formed during summer melting.
Subsequent snow then covers that lens and compacts it, gradually changing it from snow into a sludgy material called firn and finally, after several decades and with much additional accumulation adding weight above, into glacial ice. The intrepid airplane hunters computed, based on the depth of the upper ice lenses in Greenland, that 40 years of ice accumulation would have buried the planes to about 40 feet.
Third, the team factored in global warming,
burst onto the global stage in the early 1980s. Widely popularized
predictions in the early 1980s suggested the entire Earth was
massively warming; consequently, the major ice sheets were seen as
being in danger of melting. They reasoned that if the Greenland ice
sheet was actually melting, the planes would be relatively easy to
Refining the Search
In August 1981, Epps and Taylor traveled to
vicinity of the crash. Using photographs taken by the crews and their
rescuers in 1942, the aircraft hunters began to slowly narrow and
refine their search. By the mid-1980s, they were confident enough of
the location to begin a detailed hunt through the snow and ice with
magnetometers, devices that measure magnetic fluctuations associated
with rocks and metals and consequently can act as extremely sensitive
Still, success was not easy. Incredibly bad weather (including blizzards and intense snow-melting warm spells), a lack of polar experience, and nasty infighting between the hunters caused delays and confusion.
After repeated unsuccessful expeditions to
the area, and
following an amazing story of perseverance to finance and continue
the search over the next several years, Epps and Taylor finally
located the planes on July 2, 1988. They attributed much of the
success to the use of subsurface radar.
Part of the hunters' problem in locating the planes was the actual depth of the ice in which the planes were entombed. By 1988, their readings had suggested that the aircraft could be under several hundred feet of snow and ice--far more than had been anticipated. Epps and Taylor returned the following summer with a coring device to bring a small piece of a plane to the surface. There was no doubt that the planes of the Lost Squadron had been found. And, to the initial dismay of the hunters, the planes were fully 268 feet below the surface!
For the airplane rescuers, the story then switched to an incredible "cold drilling" operation in which hot water was used to melt a huge hole through 268 feet of solid glacial ice and an ice cave around the planes. This was incredibly dangerous work. After all, the engineers were working in extraordinarily unstable conditions with melting ice and water periodically threatening to collapse the entire tunnel and cave. Even when one of the P-38 Lightnings was finally selected and disassembled, the hunters were still faced with the problem of getting the pieces to the surface.
In an effort reminiscent of a skyscraper construction job, individual pieces of the sectioned plane were carefully hoisted by chain to the top of the 30-story hole. Successfully recovered, the plane was nicknamed the "Glacier Girl" and transported back to the United States. It now resides in an air museum in Middlesboro, Kentucky, where it is slowly and carefully being reconstructed.
for climatologists, one puzzle remained: Why was there so much ice
over these planes at a time when global warming and the melting of
the polar icecaps were such big news?
It's possible that the massive accumulation of snow and ice above the eight warplanes was merely local; there may have been melting elsewhere on the huge ice sheet. A large accumulation of snow and ice over a 50-year period in one location doesn't necessarily say much about the overall state of the ice sheet.
However, the scientific literature of the 1990s provides some surprising information. For example, in 1991, German scientist Philippe Huybrechts found that a 1 degrees C warming would actually increase the snow and ice mass of Greenland, due to increased snowfall. Another scientist, Roger Braithwaite from the Greenland Geological Survey in Denmark, published an article entitled "Is the Greenland Ice Sheet Getting Thicker?" in which he concluded that the issue is very complex and that no simple answer could be defended at that time.
In 1995, Mikhail Verbitsky of Yale University and Robert Oglesby from Purdue University developed a climate model that indicated a buildup of greenhouse gases would lead to a complex pattern of thickening and thinning of Greenland's ice sheet. And Ian Smith of the Australian Research Agency CSIRO published a scientific article on the subject in 1999 that carefully considered the relationship among temperature, melting, and/or accumulation in Greenland.
Due to the cooling of the surrounding seas, Smith determined that accumulation rates may have decreased from 1950 to 1991, but that melting may have decreased even more. Smith concluded, "This implies that the overall mass balance may have increased over the period 1950�1991," which covers much of time the planes of the Lost Squadron were stranded in the ice.
Finally, area temperature records from the United Nations's Intergovernmental Panel on Climate Change (IPCC) verify what other climatologists have found about cooling in Greenland. Monthly temperature anomalies for the area near the landing site reveal a cooling of 2.25 degrees F from the time the Lost Squadron touched down in southeastern Greenland until the P-38 Glacier Girl was restored to sunlight 50 years later.
What does that climate information mean? Contrary to what people might expect, southeastern Greenland has been cooling for the last 50 years. Scientific literature indicates that linking temperature trends to changes in ice volume involves a complicated set of processes that defy the simplistic notions about global warming.
This point was emphasized in a report published earlier this year in the journal Science. In 1999, NASA researchers surveyed Greenland�s ice sheet using an airborne laser altimeter, which measured the thickness of the entire ice sheet and compared the new thicknesses to 1994 values.
The results gave a mixed story: Above 2,000 meters, on average, the ice sheet was generally the same thickness as it had been five years earlier, but had some regions of local thickening or thinning. In general, melting does predominate at lower elevations, with melting rates exceeding one meter per year close to the coast. In their report, the NASA authors were careful not to link the ice volume changes to global warming.
So again we learn that things in the real world are never as simple as they might seem. But the story of the Lost Squadron remains an amazing saga that stretches across the entire spectrum of climatology and meteorology. From the initial bad weather that forced the planes down, to the saga of locating and returning the planes to the surface, and finally to studies of long-term ice growth and climate change, the story will forever be a part of our continuing relationship with the elements.
For more information about the recovery and restoration of the Lost Squadron, visit their Web site at .
From Weatherwise magazine, November/December 2000