Russian researchers are studying images taken by the
\ncrew of the International Space Station to better understand
\nthe catastrophic glacier collapse and landslide that
\noccurred on the northern slope of Mount Kazbek in September
\n— information that may help us better understand our home
\nplanet.<\/p>\n
\nOn Sept. 20, 2002, the collapse of a hanging glacier on the
\nslope of Mount Dzhimarai-Khokh onto the Kolka glacier on
\nMount Kazbek triggered an avalanche of ice and debris that
\nburied several small villages in the Russian Republic of
\nNorth Ossetia. The avalanche killed dozens of people.
\nGlacial debris dammed rivers and formed several lakes. One
\nof these lakes flooded a village, and others are threatening
\nto burst their new banks and form debris flows downstream.<\/p>\n
\nRussian scientists at Moscow State University are using
\nimages taken by the crew aboard the Station to measure small
\nchanges near the glacier. “We can see a slight increase in
\nthe area of a new lake near the Kolka Glacier terminus,”
\nsaid Dr. Olga Tutubalina, a scientist at Moscow State
\nUniversity. “We first sighted this lake during our field
\ntrip on Oct. 5, and the lake surface has increased from Oct.
\n6 to 19. It is potentially dangerous, because it can produce
\ndisastrous outburst mudflows,” she said.<\/p>\n
\nThe Russian investigators also include Moscow State
\nUniversity scientists Dr. Dmitry Petrakov, Dr. Victor
\nPopovnin and Sergei Chernomorets. The Russian Foundation for
\nBasic Research supports their activities. In September 2001,
\nthe team visited the Kolka Glacier to assess its state.
\nAfter the recent collapse, the team conducted an analysis of
\nimages taken by the Station crew and then organized another
\nfield trip to gather additional information. They plan to
\ncontinue monitoring the area using both satellite images and
\nastronaut photography.<\/p>\n
\nDr. Lev Dessinov, of the Russian Academy of Sciences,
\ncollaborated with scientists at NASA’s Johnson Space Center,
\nHouston, to establish global glacier sites as a research
\ntopic for the Crew Earth Observations project. Dessinov was
\nalso part of the team of scientists called to the Kolka area
\nimmediately after the glacier collapsed. “We collected a lot
\nof information and [NASA astronaut photographs] were one of
\nour main data sources,” Dessinov said.<\/p>\n
\nThe Expedition 5 crew, Commander Valery Korzun, Flight
\nEngineer Sergei Treschev and NASA Station Science Officer
\nPeggy Whitson, have been photographing this area since the
\nbeginning of the mission in June as part of the Russian
\nURAGAN and U.S. Crew Earth Observations projects, which are
\nstudying changes in the world’s glaciers. On Aug. 13, about
\none month before the glacier collapsed, the crew
\nphotographed the mountain. Although scientists have
\npredicted the possibility of large glacial collapses, at the
\ntime of the first image, no one predicted that tragedy would
\nstrike the mountain village of Karmadon a little more than a
\nmonth later. On a visit to the Station, Shuttle crewmembers
\nphotographed the aftermath of the collapse on Oct. 17.
\nStation crewmembers then took a spectacular three-
\ndimensional oblique image on Oct. 19.<\/p>\n
\nThe crew has been able to provide international scientists
\nwith images, such as those taken for the glacier
\nresearchers, by using motion compensation techniques
\ndeveloped by previous Station crews. Crewmembers can use
\nhigh-magnification lenses to survey features around the
\nworld from their relatively low orbit, obtaining spatial
\nresolutions as good as six meters. This means scientists can
\nuse photographs taken from the Station to study changes that
\nare occurring in very small features on the Earth’s surface.
\nThese images can augment satellite data, especially when
\nastronauts take advantage of varying Sun angles on the
\nlandscape to capture three-dimensional views. This
\ntechnique, which was used to take a photo of the glacier
\narea on Oct. 19, provides imagery that is both visually
\nspectacular and easy to interpret. <\/p>\n
\n“The (Oct. 19) image gives us a rare opportunity to try and
\nestimate the volume of the initial glacier collapse,” said
\nChernomorets.<\/p>\n
\nThe first five Space Station crews have taken more than
\n41,000 images of the Earth using digital still cameras, 35
\nmm cameras, 70 mm cameras and a variety of lenses.
\nCrewmembers are able to produce higher-resolution
\nphotographs with the high-magnification lenses by learning
\nto compensate for the relative motion of the Earth below
\nthem as they point their cameras through a specially built
\nwindow in the Station’s Destiny laboratory.<\/p>\n
\nThe photographs of the Kolka glacier are on the Internet at:
\n
\nhttp:\/\/www.jsc.nasa.gov\/images\/eol\/kolka.html <\/a><\/p>\n