Mapping change in the Arctic

If you live in, work in, or study the Arctic, you may have noted firsthand the evidence of warming felt more strongly there than in most other places on Earth. Summer sea ice is drawing back from coasts, glaciers are waning, ice sheets are discharging rivers of summer melt; once permanently frozen ground is turning to mush, and landscapes are changing as shrubby vegetation advances northward and plants have a longer growing season. This outsized warming in the Arctic is called Arctic amplification, and was predicted by climate scientists to occur as global atmospheric carbon dioxide concentrations rise.

Longer growing seasons and warmer temperatures provide a more favorable environment for this alder seedling to colonize the Arctic tundra, which once was covered only by lichens and low-growing plants. As taller vegetation and shrubbery increase, they serve as an indicator of a strongly warming Arctic. (Photograph courtesy Gerald Frost, University of Virginia/NOAA Climate Watch)

Longer growing seasons and warmer temperatures provide a more favorable environment for this alder seedling to colonize the Arctic tundra, which once was covered only by lichens and low-growing plants. As taller vegetation and shrubbery increase, they serve as an indicator of a strongly warming Arctic. (Photograph courtesy Gerald Frost, University of Virginia/NOAA Climate Watch)

But exactly how much change is occurring in the Arctic’s vital signs, and where? Warming and change do not affect every place in the Arctic equally. The pace and place of change are also influenced by other variables, such as weather patterns. NASA possesses a wealth of data on Arctic change from its Earth observing missions and related studies. But until now, unlocking the information in these data has required considerable technical and scientific expertise and time.

This map shows NDVI anomalies for May 2010, compared to the long-term average for the period 1982 to 2010.

This map from Satellite Observations of the Arctic for May 2010 indicates a strong increase in Arctic greenness, as indicated by strong positive Normalized Difference Vegetation Index (NDVI) anomalies (greens), compared to the long-term average for the period 1982 to 2010. NDVI is a measure of plant greenness.

To make data on Arctic change accessible to a wider audience of non-specialist scientists, policymakers, and others, NSIDC has developed a new Web site that lets you explore data on change in the Arctic over time, without any programming or specialized tools. The site, Satellite Observations of Arctic Change (SOAC), allows you to view and interact with data on a map. You can animate a time series, zoom in or out, and view a bar graph of anomalies over time. Links to the source data and documentation are also included. Additional pages provide brief scientific discussion, and overviews of the scientific importance of these data.

Presently, SOAC offers seven data sets:

·      Air temperatures: Near-surface air temperature anomalies, from MERRA, 1979 – 2012
·      Water vapor: Total column water vapor anomalies, from MERRA, 1979 – 2012
·      Sea Ice: Monthly mean sea ice concentration anomalies, from the NSIDC Sea Ice Index, 1979 – 2012
·      Snow cover: Snow cover duration anomalies, from Rutgers Snow Cover Lab, 1966 – 2012
·      Vegetation/greenness: Monthly mean NDVI anomalies, from GIMMS, 1982 – 2010
·      Frozen ground: Soil non-frozen period anomalies, from NASA MEaSUREs, 1981 – 2010
·      Snow and ice cover: Annual minimum exposed snow and ice, from MODICE, 2000 – 2013

More data types and extended temporal coverage may be added in the future, if interest warrants and funding continues. SOAC was developed with support from NASA Earth Sciences (http://science.nasa.gov/earth-science/).

Visit Satellite Observations of Arctic Change.

Comments are closed.