NASA Image Of The Day

Retreat of Yakutat Glacier
NASA Image Of The Day
Located in the Brabazon Range of southeastern Alaska, Yakutat Glacier is one of the fastest retreating glaciers in the world. It is the primary outlet for the 810-square kilometer (310-square mile) Yakutat ice field, which drains into Harlequin Lake and, ultimately, the Gulf of Alaska. The Operational Land Imager on the Landsat 8 satellite captured this image of the glacier and lake on Aug. 13, 2013. Snow and ice appear white and forests are green. The brown streaks on the glaciers are lateral and medial moraines. Over the past 26 years, the glacier?s terminus has retreated more than 5 kilometers (3 miles). What is causing the rapid retreat? University of Alaska glaciologist Martin Truffer and colleagues pointed to a number of factors in their 2013 study published in the Journal of Glaciology. The chief cause is the long-term contraction of the Yakutat Ice Field, which has been shrinking since the height of the Little Ice Age. Once part of a much larger ice field, Yakutat has been contracting for hundreds of years. As other nearby glaciers retreated, Yakutat ice field was cut off from higher-elevation areas that once supplied a steady flow of ice from the north. With that flow cut off, there simply is not enough snow falling over the low-elevation Yakutat ice field to prevent it from retreating. Beyond this natural change, human-caused global warming has hastened the speed of the retreat. Between 1948?2000, mean annual temperatures in Yakutat increased by 1.38° Celsius (2.48° Fahrenheit). Between 2000 and 2010, they rose by another 0.48°C (0.86°F). The warmer temperatures encourage melting and sublimation at all ice surfaces exposed to the air. In the past few years, the breakdown of a long, floating ice tongue has triggered especially dramatic changes in the terminus of Yakutat glacier. For many years, Yakutat?s two main tributaries merged and formed a 5-kilometer (3-mile) calving face that extended far into Harlequin Lake. In the past decade, satellites observed a rapid terminus retreat and the breakup of the ice tongue in 2010. As a result, the calving front divided into two sections, with one running east-west and another running north-south.  > More information and annotated images Image Credit: NASA Earth Observatory image by Robert Simmon, using Landsat data from the U.S. Geological Survey Caption: Adam Voiland...
20 Aug 2014
800x6001024x768Large

Who's Online

We have 18 guests online

Translation

English French German Italian Portuguese Russian Spanish
Latest
The latest videos
Title Filter     Display # 
# Article Title Author Hits
201 Space to Ground - 4/4/14 Administrator 114
202 Expedition 39 - Space Station Live - April 4 Administrator 99
203 Expedition 39 - Space Station Live - April 3 Administrator 93
204 Deep Space Network’s 50th Anniversary NASA Social Administrator 96
205 Expedition 39 - Space Station Live - April 2 Administrator 107
206 Expedition 39 - Space Station Live - April 1 Administrator 113
207 Expedition 39 - Space Station Live - March 31 Administrator 100
208 Expedition 39/40 - Interview with Flight Engineer Cosmonaut Alexander Skvortsov Administrator 139
209 Expedition 39/40 - Interviews with ISS Flight Engineer and Commander Steve Swanson Administrator 164
210 Expedition 39 - Crew Profile Administrator 116
211 Expedition 39/40 - Mission Overview Administrator 173
212 Expedition 39 - Space Station Live - March 28 Administrator 97
213 Expedition 39/40 - Soyuz TMA-12M Hatch Opening and Other Activities Administrator 243
214 Expedition 39/40 - Soyuz TMA-12M Docking Administrator 209
215 Expedition 39 - Space Station Live - March 27 Administrator 94
216 Expedition 39-40 - Soyuz TMA-12M Update Space Station Live Administrator 174
217 Expedition 39 - Space Station Live - March 26 Administrator 88
218 Expedition 39-40 - Soyuz TMA-12M Post-Launch Interviews Administrator 121
219 Expedition 39/40 - Soyuz TMA-12M Update Administrator 199
220 Expedition 39/40 - Soyuz TMA-12M Launch Replay Administrator 168
221 Expedition 39/40 - Soyuz TMA-12M Launch Administrator 253
222 Expedition 39/40 - Soyuz TMA-12M Pre-launch Activities Administrator 145
223 Expedition 39 - In-Flight Event for JAXA - March 25 Administrator 110
224 Expedition 39 - Space Station Live - March 25 Administrator 81
225 NASA Social: Meet Astronaut Karen Nyberg Administrator 90
226 Expedition 39/40 - Pre-Launch Crew News Conference in Baikonur, Kazakhstan Administrator 169
227 Expedition 39 - Space Station Live - March 24 Administrator 76
228 Expedition 39/40 Soyuz TMA-12M Spacecraft Mating and Rollout to the Launch Pad in Baikonur, Kazakhstan plus Launch Pad Interviews Administrator 223
229 Media Teleconference on an Asteroid Initiative Broad Agency Announcement Administrator 145
230 Skylab 4 Pilot William Pogue Honored at United States Astronaut Hall of Fame Administrator 124
231 Expedition 39/40 - Crew Activities in Baikonur, Kazakhstan - March 21 Administrator 149
232 Space to Ground - 3/21/14 Administrator 82
233 Expedition 39 - Space Station Live - March 21 Administrator 83
234 Expedition 38 - Live Interviews with Flight Engineer Michael Hopkins Administrator 143
235 Expedition 39 - Space Station Live - March 20 Administrator 83
236 Expedition 39/40 - Crew Activities in Baikonur, Kazakhstan Administrator 164
237 Expedition 39 - Space Station Live - March 19 Administrator 90
238 Expedition 40/41 - Crew News Conference Administrator 275
239 Expedition 40/41 - Video B-Roll Feed of Crew Training Administrator 202
240 ISS Mission Control On-Console Interview with the Digital Learning Network - March 18 Administrator 92
241 Expedition 39 - Space Station Live - March 18 Administrator 72
242 Expedition 39 - Space Station Live - March 17 Administrator 86
243 Expedition 39 - Space Station Live - March 14 Administrator 103
244 Space to Ground - 3/14/14 Administrator 81
245 Expedition 39/40 - Crew Departure from Star City, Russia for Baikonur, Kazakhstan Administrator 244
246 Expedition 39 - Space Station Live - March 13 Administrator 92
247 Expedition 39 - In-Flight Event with the U S Senate Youth Group and NASA Administrator Charlie Bolden Administrator 141
248 Expedition 39 - In-Flight Event for JAXA for Japanese Reporters - March 13 Administrator 89
249 ESD Quarterly Update #5: Acing the Test Administrator 114
250 Expedition 39 - Space Station Live - March 12 Administrator 66
 
«StartPrev12345678910NextEnd»
Page 5 of 28
Copyright © 2014 Space-multimedia. All Rights Reserved.
Joomla! is Free Software released under the GNU/GPL License.