Ice-Spy: Declassified Satellite Images Measure Glacial Loss

U.S. spy pilot, Gary Powers (RIAN/Creative Commons).
U.S. spy pilot, Gary Powers (RIAN/Creative Commons).

Since the 1960s, images from spy satellites have been replacing the use of planes for reconnaissance intelligence missions. Making the transition from planes to satellites was prompted by an infamous U-2 incident during the Cold War when U.S. pilot Francis Gary Powers’ U-2 spy plane was shot down in Soviet air space. Five days later, after considerable embarrassment and controversy, President Eisenhower approved the first launch of an intelligence satellite, part of a new scientific electronic intelligence system termed ELINT. Today, declassified images from satellites have resurfaced to support scientific research on glaciers and climate change.

Scientists from Columbia University and the University of Utah created 3-D images of glaciers across the Himalayas, and Bhutan specifically, by using satellite imagery to track glacial retreat related to climate change. Joshua Maurer et al. published the results of their Bhutan study in The Cryosphere to help fill in the gaps of “a severe lack of field data” for Eastern Himalayan glaciers.

Looking down the valley from a glacier the team visited in Bhutan in 2012 (Source: Joshua Maurer).
Looking down the valley from a glacier the team visited in Bhutan in 2012 (Source: Joshua Maurer).

Being able to understand and quantify ice loss trends in isolated mountain areas like Bhutan requires physical measurements that are currently not available due to complex politics and rugged terrain. Luckily, the scientists found an alternative route to reach their measurement goals by comparing declassified spy satellite images from 1974 with images taken in 2006 using the ASTER, Advanced Spaceborne Thermal Emission and Reflection Radiometer, a spaceborne imaging instrument aboard NASA’s earth-observing Terra satellite.

Bhutan has hundreds of glaciers and glacial lakes. Physical data collection can be a daunting process in such a region considering the vast quantity of glaciers in combination with freezing weather conditions and high winds. The lead researcher of the Bhutan study, Joshua Maurer from Columbia University, experienced firsthand the logistical challenges associated with directly measuring changes in glacial ice density when conducting research on glacial change in the remote and high-altitude regions of Bhutan. Inspired by this difficult experience, Maurer collaborated with other scientists from the University of Utah to find alternative methods for quantifying trends in glacial ice density.

Camera system for a Discoverer-Corona spy satellite (Tim Evanson/Creative Commons).
Camera system for a Discoverer-Corona spy satellite (Tim Evanson/Creative Commons).

Maurer and the team of researchers devised a strategy to use declassified satellite images to collect data by a process of photogrammetry, the use of photographs to survey and measure distances. More than 800,000 images from the CORONA Satellite program, taken in the 1970s and 1980s, have been sent to the U.S. Geological Survey from the Central Intelligence Agency (CIA), and made available to the public.

Several advanced mathematical tools are necessary for making measurements from raw image files. For this particular study, the team used the declassified photos from the 1970s to track changes in glacial ice coverage over time when compared to more recent images from the Hexagon Imagery Program database taken by the Swiss-based Leica Geosystems’ airborne sensors in 2006. Once a timeline was created from the pictures, measurements were made using NASA’s space tool ASTER. This method, Maurer argues, is the solution for measuring massive amounts of hard-to-access data.

Landsat 8 satellite image, with studied glaciers outlined in white (Source: Joshua Maurer).
Landsat 8 satellite image, with studied glaciers outlined in white (Source: Joshua Maurer).

But making precise measurements integrating several sets of images from different periods of time is no simple task. Pixel blocks, minute areas of illuminations from which images are composed, were processed to correspond with regions designated on the film. The blocks of pixels were then selected to maximize coverage of glaciers and avoid regions with cloud cover. Computer-generated algorithms transform these blocks of image into measurements using automated point detectors and descriptors.

Images from the declassified satellite database may suffer from a lack of clarity, so it was also important for the researchers to address these issues. For example, debris-covered glaciers are difficult to distinguish from surrounding terrain using visible imagery only. Furthermore, loud cover and poor radiometric sensing data in remote areas can prevent complete observation. In order to address challenges like these, images were analysed by a computer and then manually edited to more accurately match glacial extent in the year that the image was taken. In order to prevent statistical errors, the research team focused on a select sample size of glaciers representative of the area being studied.

Satellite image analysis like that performed in Bhutan has become increasingly important in the study of climate change. In terms of glaciers, these analyses have proven valuable to scientists in reaching otherwise hard to access data. The main findings of the study were that glacial retreat in the last fifty years is significantly contributing to the creation of glacial lakes in the East Himalayan region and associated flood outbursts. A glacial lake outburst flood is a type of flood that occurs when the dam containing a glacial lake fails due to a buildup of water pressure. Bhutan has low lying river planes that are vulnerable to such floods, so measuring ice loss can help scientists identify which dams are at risk of bursting. This can further help policy makers take appropriate action to mitigate potential disaster.

Declassified Corona spy satellite image from the year 1974 showing the glaciers in Bhutan (Source:Joshua Maurer).
Declassified Corona spy satellite image from the year 1974 showing the glaciers in Bhutan (Source: Joshua Maurer).

Following the successful completion of the Bhutan study, Maurer and his team were granted additional funding from a NASA Earth and Space Science fellowship to expand the same methodology to other regions of the Himalayas. Understanding ice loss is important, and the effort to overcome logistical barriers is worthwhile.

“Ice loss will impact hydropower, agriculture, and ecosystems in the region,” Maurer told GlacierHub. Understanding the glacial ice balance in the Himalayan region and the rates of ice loss assists adaption plans for building strategic dams and reservoirs for seasonal water storage. These actions could result in more people being better off, more people receiving reliable electricity, and a reduced risk of moraine dam outbursts.

While observation of changing trends in glacier mass may not be complete, the information that is available due to declassified spy satellite imagery positively contributes to the Himalayan people’s capabilities regarding future impacts linked to ice loss, according to Maurer et al. Overall, results from spy satellite images have enhanced the understanding of potential glacier contribution to sea-level rise, impacts on water resources, and hazard potential for high mountain regions and downstream populations in Asia.

 

 

Oxonians Retrace Paths Through Spitsbergen 93 Years Later

The team and their guide on the summit of Poincarétoppen (Source: Liam Garrison/Spitsbergen Retraced
The team and their guide on the summit of Poincarétoppen (Source: Liam Garrison/Spitsbergen Retraced).

During summer, a team of four students from Oxford University, led by undergraduate James Lam, completed a 184-mile expedition across the Ny-Friesland ice cap in Spitsbergen, Norway. Accompanied by a guide, Endre Før Gjermundsen, they skied across the ice cap from July 31 to August 29, retracing the route of a similar expedition conducted by four Oxford University undergraduates in 1923, and collecting scientific data about glaciers along the way.

Spitsbergen is the largest island in the Svalbard archipelago, a territory located within the Arctic circle. Svalbard has more than 2,100 glaciers, constituting 60 percent of its land area, many of which are found on Spitsbergen. The island is also home to many mountains and fjords, giving rise to its name, which means ‘pointed mountains’ in Dutch.

Chydeniusbreen as seen in a photograph taken in 1923 (Source: R. Frazer/The Geographical Journal)
Chydeniusbreen as seen in a photograph taken in 1923 (Source: R. Frazer/The Geographical Journal).

Ny-Friesland in east Spitsbergen has received limited attention from scientists, with little data having been recorded since the 1923 expedition. As such, the team of undergraduates worked with researchers from Oxford University and the University Centre in Svalbard (UNIS) to collect different forms of data on the island’s environment, glaciers and climate.

The expedition was inspired by the discovery of original maps and photos from the 1923 expedition in the archives of the Oxford University Exploration Club. All of the team members, James Lam, Jamie Gardiner, Will Hartz and Liam Garrison, have personal skiing and mountaineering experience spanning three different continents. Nevertheless, they undertook nine months of rigorous training and extensive preparations to ensure the success of both the scientific and physically strenuous aspects of the expedition.

Apart from skiing trips, the training regime included tyre-dragging in Port Meadow, Oxford. (Source: Liam Garrison/Spitsbergen Retraced)
Apart from skiing trips, the training regime included tyre-dragging in Port Meadow, Oxford (Source: Liam Garrison/Spitsbergen Retraced).

During the trip, the students photographed, recorded and collected DNA samples from vascular plants encountered at ten different locations between Duym point in the east and the terminus of Nordernskiold glacier in the west. These samples are currently being analyzed at UNIS and will be added to the Svalbard Flora database. They will provide valuable contributions to understandings of dispersal patterns on glaciers, particularly as there is only one other set of biological data for East Spitsbergen.

The camps of the teams on the 1923 and 2016 expeditions (Sources: R. Frazer/The Geographical Journal and Liam Garrison/Spitsbergen Retraced)
The camps of the teams on the 1923 and 2016 expeditions (Sources: R. Frazer/The Geographical Journal and Liam Garrison/Spitsbergen Retraced).

Using a drone, the students successfully mapped three sections of the Chydeniusbreen glacier. This will be used to create 3D maps of these areas, which will be compared to satellite data and the Norwegian Polar Institute’s models of the glacier to measure glacial change. The team was also able to successfully repeat 25 of the landscape photographs taken on the 1923 expedition. These will be used to practice photogrammetry, the science of measurements done using photographs, to be used in conjunction with the 3-D maps and satellite data to track glacial change in Ny-Friesland.

Two team members ascending the unclimbed west ridge of Newtontoppen (Source: Endre Før Gjermundsen/Spitsbergen Retraced)
Two team members ascending the unclimbed west ridge of Newtontoppen (Source: Endre Før Gjermundsen/Spitsbergen Retraced)

One of the aims of the 1923 expedition was to summit hitherto unclimbed peaks. In the same vein, the 2016 team summitted 8 different peaks, including a number of mountains climbed by the original expedition, such as Poincarétoppen, Mount Chernishev and Mount Irvine. The students also made the first ever ascent of the West Ridge of Newtontoppen, Svalbard’s highest mountain (5,666 ft). These efforts were carried out alongside the scientific aims of the expedition, with the team remaining camped in the base camp of Loven Plateau for a week in order to pursue repeat photography and data collection.

GlacierHub caught up with two of the team members for a short interview about the expedition and what the team intends to do now that they have returned.

GlacierHub: What happens now that the expedition is over?

James Lam, team leader: Now that the expedition is over, I am working to process the data that we collected. I’m collaborating with the Earth Sciences Department in Oxford as well as UNIS and the Norwegian Polar Institute. We hope to be able to publish our findings in due course. We are currently also working with Talesmith (a London-based production company specializing in natural history) to create a film or television series about the expedition.

GH: What was one of the most memorable things about this expedition?

James attempting to recover equipment in a storm (Source: Liam Garrison/Spitsbergen Retraced)
James attempting to recover equipment in a storm (Source: Liam Garrison/Spitsbergen Retraced)

JL: One of the most memorable parts of the expedition was a storm that we were caught in for about three weeks. Despite spending five hours digging into the glacier for shelter and building six foot walls with 100 km/h gusts, it was still too windy to put up the tents, so we were forced to spend the night in a survival shelter. After nine hours huddled together in the shelter, the wind finally died down enough to be able to put up the tents. Luckily, no critical equipment was broken, and we were able to continue after a rest day.

GH: How did it feel embarking on an expedition like this, given the somewhat controversial history of exploration by the British Empire?

A note that the 1923 expedition team left in a thermometer case on the summit of Mt Chernishev (Liam Garrison/Spitsbergen Retraced)
A note that the 1923 expedition team left in a thermometer case on the summit of Mt Chernishev (Liam Garrison/Spitsbergen Retraced).

Jamie Gardiner, team historian: There is quite an anti-intellectual tendency in some quarters to indiscriminately equate the history of exploration with that of imperialism. In 1923, Svalbard was not only terra incognita but terra nulla. Accordingly, it’s rather hard to construct any kind of narrative of exploitation of native peoples. As it happens, in 1925, Britain acted as a signatory of the Svalbard Treaty, which placed Svalbard under Norwegian sovereignty. The treaty expressly forbade militarization and granted unilateral rights to mineral exploitation provided the environmental priorities enshrined were upheld. [The treaty was crafted] without first understanding what it is that is conserved. Therein the mapping of Svalbard had such a key importance.

 

The team will be releasing a publicly available report about their expedition, along with a documentary to share their journey with a wider audience and compare their polar narrative with that found in excerpts of three diaries from the original expedition. The trailer can be viewed here. Updates about their progress and more spectacular photographs can also be viewed on their Facebook and Twitter pages.