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Bering Glacier started to surge again in April, following a 7-month period of minor retreat and near-stagnation. Part of the terminus advanced about 750 m between May 19th and June 1. Bering—the largest surging glacier on Earth—recently experienced a major, 17-month-long surge that ended in September 1994. That surge displaced part of the terminus about 9 km and caused a substantial increase in iceberg production. It also completely or partially covered all the islands within Vitus Lake with ice and caused significant changes in the lake's size, the ocean floor, hydrology, and water chemistry. This latest surge overrode two of the islands that are home to many species of waterfowl at the peak of the nesting season, covering several thousand nests.
On April 14, 1995, the first evidence that a new surge had begun was noted by U.S. Geological Survey volunteers from Cordova, Alaska. They observed that a section of the winter-ice cover of Vitus Lake was being compressed, resulting in a series of accordionlike folds. Many deep, fresh cracks and rifts, as well as a number of blue-water lakes forming on the glacier's surface, were also observed. These features were characteristic of the 1993-1994 surge. Once a week, the volunteers flew over Bering Glacier to observe and monitor changes in the glacier's piedmont lobe. They noted no evidence of surge activity during their weekly flights prior to April 14th. Aerial photographs of the glacier's lower margin taken in late November 1994 and in late January 1995 showed no evidence of surge activity either.
Aerial photography of the eastern piedmont lobe, terminus, and Vitus Lake made by the U.S. Geological Survey on May 1, 1995, confirmed the new fracturing and rifting, and the numerous lakes. These photographs show the terminus advancing over the north end of Beringia Noyava, the largest island in Vitus Lake, and over the south half of Pointed Island. The ice margin showed a significant amount of iceberg production, including several bergs that were more than 0.5 km long.
On May 19, 1995, oblique aerial photography confirmed that the terminus was still advancing. On the southeast shoreline of the lake, the advancing ice margin was forcing the entire drainage from the eastern part of the glacier to flow in a narrow channel, resulting in several tens of meters of shoreline retreat and the development of a high bluff. The advance and bluff cutting continued all summer long.
A 2-day visit to the glacier by Bruce Molnia on June 1 and 2, 1995, confirmed that the surge was not only affecting the eastern terminus region but also the northern piedmont lobe as much as 30 km north of the terminus. There the winter 1994-1995 snow surface was complexly fractured and rifted. Several large ice-surface lakes had reappeared in the same locations where lakes had existed during the previous surge. Whiteout conditions prevented determining whether the surge was active further upglacier. However, surveys in July and August showed that most of this part of the glacier was affected by the surge. Through late July, the terminus continued to advance over the north end of Beringia Noyava. Only the southernmost 15 m of Pointed Island remained exposed by the end of summer; more than 800 m of the island was covered since May 19th.
The USGS continues to monitor this new surge with both aerial and field observations. Emphasis has been placed on monitoring the increase in iceberg production. Of greatest concern is the number of large icebergs that enter the Pacific Ocean through the Seal River, the primary outlet of Vitus Lake. Seal River is located only about 100 kilometers from the Pacific Ocean tanker lanes that exit and enter Prince William Sound.