Teleconnection between the tropical Pacific and Antarctica

Typography

In April 2016, a large-scale breakup of land-fast ice was observed in Lutzow-Holm Bay near Syowa Station, a Japanese research facility. It was the first comparably large calving in the region since 1998. Land-fast ice is sea ice that grows along the Antarctic coast and does not move much once formed. Syowa Station is normally surrounded by land-fast ice, which makes it very difficult for even an icebreaker to reach.

In April 2016, a large-scale breakup of land-fast ice was observed in Lutzow-Holm Bay near Syowa Station, a Japanese research facility. It was the first comparably large calving in the region since 1998. Land-fast ice is sea ice that grows along the Antarctic coast and does not move much once formed. Syowa Station is normally surrounded by land-fast ice, which makes it very difficult for even an icebreaker to reach.

Such a large calving has been reported several times in the past, but the cause of ice calving in Antarctica has mostly been shrouded in mystery.

Associate Professor Shigeru Aoki of Hokkaido University’s Institute of Low Temperature Science has studied satellite imagery from 1997 to identify possible correlations between land-fast ice breakups and the climate condition data gathered at Syowa Station as well as sea surface temperature data from around the world. Land-fast ice breakup is most commonly observed in April, so Aoki investigated the latitudes where breakups of land-fast ice were observed and compared them with the data of April’s climatological variable averages, such as atmospheric pressures on the ground and seawater surface temperatures.

Read more at Hokkaido University

Image: Map showing the correlation values between the latitude of the land-fast sea ice edge in Lutzow-Holm Bay and sea surface temperature in April. Reddish parts and blue parts show positive correlations and negative correlations respectively, suggesting that ice calving occurs when seawater temperatures are high in the tropical pacific. Water temperature data were provided by the U.S. National Oceanic and Atmospheric Administration. (Credit: Aoki S., Geophysical Research Letters, April 7, 2017)