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Scientists blog from Antarctica and provide a glimpse of what it's like to do research in the field. 
What's hot in the news around climate and sea ice and what are scientists talking about now? NOTICE 07/25/18
Sea Ice Index
- Arctic
- Antarctic
- Monthly
- Daily
Blue Marble View
- Extent
- Concentration
- Anomalies
- Trends
The monthly Sea Ice Index provides a quick look at Arctic-wide changes in sea ice. It is a source for consistently processed ice extent and concentration images and data values since 1979. Monthly images show sea ice extent with an outline of the 30-year (1981-2010) median extent for that month (magenta line). Other monthly images show sea ice concentration and anomalies and trends in concentration.
Monthly Sea Ice Extent Anomaly Graph
This graph shows monthly ice extent anomalies plotted as a time series of percent difference between the extent for the month in question and the mean for that month based on the January 1981 to December 2010 data. The anomaly data points are plotted as plus signs and the trend line is plotted with a dashed grey line. Read more ...
More About Monthly Images
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Monthly Sea Ice ExtentThe monthly extent images show the expanse covered by ice at greater than 15 percent monthly mean concentration for the Arctic and Antarctic. The total extent value is given in the bottom margin. It is derived from passive microwave data. The median line (in pink) shows a typical ice extent for that month, based on data from 1981 through 2010. The area around the North Pole that the satellite does not image is assumed to be covered by ice at more than 15 percent concentration.See documentation for details. |
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Monthly Sea Ice ConcentrationThe monthly concentration images show a particular month's ice concentration with each 25 km data cell color-coded in shades of blue to white, where dark blue is zero percent ice (ocean) and white is 100 percent ice. The area around the North Pole that is not imaged by the satellite is left out of the images (dark grey circle).See documentation for details. |
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Monthly Sea Ice Concentration AnomalyThese images of anomalies in ice concentration show, in percent color-coded in shades of blue (negative anomaly) to red (positive anomaly), how much the ice concentration for a month differs from the mean calculated for that month over the 1981 through 2010 time range. The total anomalous area of sea ice for that month is also shown in the bottom margin of the image. The area around the North Pole that is not imaged by the satellite is left out of the images (light grey circle).See documentation for details. |
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Monthly Sea Ice Concentration TrendThese images of trends in sea ice concentration show if the trend in sea ice concentration at a particular grid cell location is positive or negative and give some indication of its magnitude in percent change per decade color-coded in shades of blue (negative trend) to red (positive trend). The area around the North Pole that is not imaged by the satellite is left out of the images (light grey circle).See documentation for details. |
- Extent
- Concentration
The daily Sea Ice Index provides a quick look at Arctic-wide changes in sea ice. It provides consistently processed daily ice extent and concentration images and data since 1979. Daily extent images show ice extent at concentrations greater than 15% for a given day with an outline of the typical extent for that day based on a 30-year (1981-2010) median (orange line).
Daily Sea Ice Extent Time Series
This graph provides a snapshot of changes in ice extent for the last four months. The graph shows a time series for the Northern hemisphere (solid blue line). The graph also includes a comparison line for the 1981 through 2010 average (solid grey line) that is plotted for the previous four months as well as the upcoming month. The light gray area around the 1981-2010 average line shows the two standard deviation range of the data. The graph also includes lines for selected earlier years, for comparison (dashed green line). Read more ...
More About Daily Images
  |
Daily Sea Ice ExtentThese images show the extent of ocean covered by ice at any concentration greater than 15 percent for a given day. This snapshot of current ice conditions may be missing data (missing data appears as gray dots or areas). The median line (orange in images) shows a typical ice extent for that day based on data from 1981 through 2010. The area around the North Pole that the satellite does not image is assumed to be covered by ice at more than 15 percent concentration.See documentation for details. |
  |
Daily Sea Ice ConcentrationThese images show the percentage of ice cover for each roughly 25-kilometer-square data cell that is more than 15 percent covered by ice on a given day. The daily images may be missing data (missing data appears as dark grey dots or areas). The area around the North Pole that is not imaged by the satellite is excluded from the area because there is no way to know what the concentration is within this area.See documentation for details. |
- Extent
- Concentration
- Anomalies
- Trends
The monthly Sea Ice Index provides a quick look at Antarctic-wide changes in sea ice. It is a source for consistently processed ice extent and concentration images and data values since 1979. Monthly images show sea ice extent with an outline of the 30-year (1981-2010) median extent for that month (magenta line). Other monthly images show sea ice concentration and anomalies and trends in concentration.
Monthly Sea Ice Extent Anomaly Graph
This graph shows monthly ice extent anomalies plotted as a time series of percent difference between the extent for the month in question and the mean for that month based on the January 1981 to December 2010 data. The anomaly data points are plotted as plus signs and the trend line is plotted with a dashed grey line. Read more ...
More About Monthly Images
|
Monthly Sea Ice ExtentThe monthly extent images show the expanse covered by ice at greater than 15 percent monthly mean concentration for the antarctic and Antantarctic. The total extent value is given in the bottom margin. It is derived from passive microwave data. The median line (in pink) shows a typical ice extent for that month, based on data from 1981 through 2010. The area around the North Pole that the satellite does not image is assumed to be covered by ice at more than 15 percent concentration.See documentation for details. |
|
Monthly Sea Ice ConcentrationThe monthly concentration images show a particular month's ice concentration with each 25 km data cell color-coded in shades of blue to white, where dark blue is zero percent ice (ocean) and white is 100 percent ice. The area around the North Pole that is not imaged by the satellite is left out of the images (dark grey circle).See documentation for details. |
|
Monthly Sea Ice Concentration AnomalyThese images of anomalies in ice concentration show, in percent color-coded in shades of blue (negative anomaly) to red (positive anomaly), how much the ice concentration for a month differs from the mean calculated for that month over the 1981 through 2010 time range. The total anomalous area of sea ice for that month is also shown in the bottom margin of the image. The area around the North Pole that is not imaged by the satellite is left out of the images (light grey circle).See documentation for details. |
|
Monthly Sea Ice Concentration TrendThese images of trends in sea ice concentration show if the trend in sea ice concentration at a particular grid cell location is positive or negative and give some indication of its magnitude in percent change per decade color-coded in shades of blue (negative trend) to red (positive trend). The area around the North Pole that is not imaged by the satellite is left out of the images (light grey circle).See documentation for details. |
- Extent
- Concentration
The daily Sea Ice Index provides a quick look at Antarctic-wide changes in sea ice. It provides consistently processed daily ice extent and concentration images and data since 1979. Daily extent images show ice extent at concentrations greater than 15% for a given day with an outline of the typical extent for that day based on a 30-year (1981-2010) median (orange line).
Daily Sea Ice Extent Time Series
This graph provides a snapshot of changes in ice extent for the last four months. The graph shows a time series for the Southern hemisphere (solid blue line). The graph also includes a comparison line for the 1981 through 2010 average (solid grey line) that is plotted for the previous four months as well as the upcoming month. The light gray area around the 1981-2010 average line shows the two standard deviation range of the data. The graph also includes lines for selected earlier years, for comparison (dashed dark blue line). Read more ...
More About Daily Images
|
Daily Sea Ice ExtentThese images show the extent of ocean covered by ice at any concentration greater than 15 percent for a given day. This snapshot of current ice conditions may be missing data (missing data appears as gray dots or areas). The median line (orange in images) shows a typical ice extent for that day based on data from 1981 through 2010. The area around the North Pole that the satellite does not image is assumed to be covered by ice at more than 15 percent concentration.See documentation for details. |
|
Daily Sea Ice ConcentrationThese images show the percentage of ice cover for each roughly 25-kilometer-square data cell that is more than 15 percent covered by ice on a given day. The daily images may be missing data (missing data appears as dark grey dots or areas). The area around the North Pole that is not imaged by the satellite is excluded from the area because there is no way to know what the concentration is within this area.See documentation for details. |
