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ChArctic Interactive Sea Ice Graph
How to use ChArctic
Developed at NSIDC with support from NASA, the ChArctic Interactive Sea Ice Graph enables users to more easily access and explore NSIDC’s Sea Ice Index data set.
With this tool, you can:
- Visualize sea ice extent (area of ocean with at least 15 percent sea ice concentration) data for the Arctic and Antarctic.
- View and compare sea ice extent data for any year or any combination of years from 1979 to present (including near-real-time daily data).
- Alternate climatology displays between either average matched with standard deviation, or median matched with interquartile and interdecile ranges.
- Choose from a variety of palettes to distinguish between different years, and toggle on/off vertical gridlines.
- Start the graph at any month of the year.
- Zoom in on an area of interest and reset to the standard display.
- Get daily sea ice extent values by rolling your cursor over a line in the graph.
- See a corresponding daily sea ice concentration image by clicking on a line in the graph.
- Download your customized graph or any of the corresponding daily sea ice concentration images.
About ChArctic data
Data and images shown in Charctic use passive microwave data from the Defense Meteorological Satellite Program (DMSP) F17 and F18 Special Sensor Microwave Imager/Sounder (SSMIS). Data sets include the Sea Ice Index, Near-Real-time DMSP SSM/I-SSMIS Daily Polar Gridded Sea Ice Concentrations, and the NASA-produced Sea Ice Concentrations from Nimbus-7 SMMR and DMSP SSM/I Passive Microwave Data.
The underlying data used to produce these images and graphs may be obtained from NSIDC. NSIDC produces the daily extent values using a five-day trailing mean. Graphs shown here may vary slightly from graphs displayed in Arctic Sea Ice News & Analysis, due to differences in handling leap years. However, the underlying data values are the same that NSIDC displays for its daily extent image and graph.
If you have questions or problems, please contact NSIDC User Services at nsidc@nsidc.org.