Using meteorological metrics, we were able to forecast two subsequent frostquake events in January 2014 that coincided with reports on social media. These occurrences became the first large-scale documented frostquakes in Canada. These were identified as a rare phenomenon called cryoseism, or more commonly known as frostquakes. Caption by Kathryn Hansen.Following the ice storm of December 2013 in southern Ontario, the general public heard noises that resembled falling trees and reported these occurrences on social media. NASA Earth Observatory images created by Jesse Allen, using digital photographs provided by Kelly Brunt, MABEL campaign. So we were pleasantly surprised when we were able to use the imagery to make a wicked cool observation of quake-induced change.” “It is intended for MABEL validation and not necessarily as a scientific instrument in its own right. “This was the first time that we successfully used the MABEL camera in the field,” said Brunt.
Supraglacial lakes are ephemeral, and they can fill and drain on short timescales even without earthquakes or other dramatic events. Brunt cautions that while she is pretty sure the snow avalanches and debris slides can be attributed to the quake, she is less certain about the drainage event. The uplift displaced the remaining water, changing the shape of the shoreline. In this case, it appears to have lifted up and formed a mound in center of the lake.
When melt water travels through a glacier's plumbing, the ice responds. The third image (below) shows the avalanche in relation to Seward Glacier. When scientists flew back over the site on July 21 (second image), snow from a large avalanche had cascaded down the mountainside and obscured remnants of the older slide. Rocks and debris from a previous landslide are littered across the young, steep slopes alongside Seward Glacier. One effect is apparent in the digital photograph at the top of this page, which was taken on July 16, one day before the quake. Flights over the region just before and after the event provided an uncommon view of an earthquake's effect on the snow-and-ice covered landscape.
Their flight paths were taking them as close as 2 kilometers (1.2 miles) from the epicenter of the earthquake. The MABEL team was already scheduled to make two flights near Seward Glacier in late July when a colleague back in Maryland alerted them to the earthquake. The camera came in handy thanks to some lucky timing. The images from that camera are typically used to visually confirm the type of surface-ice, open water, or melt ponds-being measured by MABEL's laser pulses. Next to MABEL in the nose cone of NASA's high-altitude ER-2 aircraft, scientists placed a digital camera. The instrument has nothing to do with earthquakes rather, scientists are using it to develop processes for interpreting data from ICESat-2, a satellite scheduled for launch in 2017. Meanwhile in Fairbanks, Alaska, NASA glaciologist Kelly Brunt and fellow scientists, engineers, and pilots were gearing up for near-daily flights with an airborne instrument called the Multiple Altimeter Beam Experimental Lidar, or MABEL. On July 17, 2014, a magnitude-6.0 earthquake struck beneath Seward Glacier in northwestern Canada, 99 kilometers (62 miles) north-northwest of Yakutat, Alaska, according to the Alaska Earthquake Information Center. The fortuitous timing of some recent NASA science flights gave scientists a rare opportunity to see what can happen when Earth's polar regions are shaken by an earthquake.
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