Arctic Sea Ice Continues a Trend of Shrinking Maximum Extents

This visualization shows the Arctic sea ice as it expands from October 1, 2017 to its annual maximum extent that occurred on March 17th, 2018.This video is also available on our YouTube channel. || Sea ice in the Arctic grew to its annual maximum extent on March 17, 2018, joining 2015, 2016, and 2017 as the years with the lowest maximum extents on record, according to scientists at the National Snow and Ice Data Center (NSIDC) and NASA. The Arctic sea ice cover peaked at 5.59 million square miles (14.48 million square kilometers), making it the second lowest maximum on record, at about 23,000 square miles (60,000 square kilometers) higher than the record low maximum reached on March 7, 2017. This animation runs from October 1, 2017 to March 17, 2018, the date that the maximum sea ice extent occurred. The images shown here portray the sea ice as it was observed by the AMSR2 instrument onboard the Japanese Shizuku satellite. The opacity of the sea ice shown in this animation is derived from the AMSR2 sea ice concentration. The blueish white color shown on the sea ice is derived from the AMSR2 89 GHz brightness temperature data. || This image shows the maximum extent of the Arctic sea ice that occurred on March 17th, 2018. The yellow line indicates the 30 year average maximum extent calculated from 1981 through 2010. The date is shown in the upper left corner. || This image shows the maximum extent of the Arctic sea ice that occurred on March 17th, 2018. The yellow line indicates the 30 year average maximum extent calculated from 1981 through 2010. On this image, the date is not displayed. || This image shows the maximum extent of the Arctic sea ice that occurred on March 17th, 2018. The date is not displayed. || The above visualization without dates. || Dates with transparency that correspond to the above visualization.

This visualization shows the age of the Arctic sea ice between 1984 and 2016. Younger sea ice, or first-year ice, is shown in a dark shade of blue while the ice that is four years old or older is shown as white. A bar graph displayed in the lower right corner quantifies the area in square kilometers covered by each age category of perennial sea ice. || One significant change in the Arctic region in recent years has been the rapid decline in perennial sea ice. Perennial sea ice, also known as multi-year ice, is the portion of the sea ice that survives the summer melt season. Perennial ice may have a life-span of nine years or more and represents the thickest component of the sea ice; perennial ice can grow up to four meters thick. By contrast, first year ice that grows during a single winter is generally at most two meters thick.Below is an animation of the weekly sea ice age between 1984 and 2016. The animation shows the seasonal variability of the ice, growing in the Arctic winter and melting in the summer. In addition, this also shows the changes from year to year, depicting the age of the sea ice in different colors. Younger sea ice, or first-year ice, is shown in a dark shade of blue while the ice that is four years old or older is shown as white. A color scale identifies the age of the intermediary years.A graph in the lower, right corner the quantifies the change over time by showing the area in millions of square kilometers covered by each age category of perennial sea ice. This graph also includes a memory bar - the green line that here represents the current maximum value seen thus far in the animation for the particular week displayed. For example, when showing the first week in September, the memory bar will show the maximum value seen for all prior years on 10/30/2016. || This visualization is the same as the one above, except that the areas where no data is available are displayed in the first 330 frames. || This animation is the same as the one above, except that the animation begins in January of 2000. || A still image of the sea ice age for week 37 of 2016 with a graph overlay showing the remaining millions of kilometers of sea ice by age. || A still image of the sea ice age for week 37 of 1984 with a graph overlay showing the remaining millions of kilometers of sea ice by age. || The weekly sea ice age without the graph overlay. || The overlay with the graph of the annual sea ice minimum showing the perennial sea ice by age in square kilometers with transparency.