New and improved ELOKA Web site


The Exchange for Local Observations and Knowledge of the Arctic (ELOKA) Web site, hosted by NSIDC, has been reformatted and updated for easier navigation. The home page now has a rolling image gallery as well as featured interviews with elders, featured data and background imagery of Arctic landscapes.  Check it out at

image of eloka web site

ELOKA facilitates the collection, preservation, exchange, and use of local observations and knowledge of the Arctic. ELOKA provides data management and user support, and fosters collaboration between resident Arctic experts and visiting researchers.

Learn more about ELOKA at

Satellite Observations of Arctic Change

NSIDC now offers a new Web site, Satellite Observations of Arctic Change (SOAC) with interactive maps of the Arctic based on NASA satellite and related data. The site allows users to explore how conditions in the Arctic have changed over time. SOAC is available at

This sample image

This sample image from Satellite Observations of Arctic Change shows near-surface air temperature anomalies for October 2012, along with a bar chart of anomalies over time.

Presently, SOAC offers seven data sets:

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

Users may 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.

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 Science (

NSIDC User Services welcomes your feedback on SOAC. Please contact us at

New life for old data: Nimbus Data Rescue Project publishes first data set

Back in the 1960s, technology to process massive amounts of data and imagery did not exist. Advancements in technology now allow for the processing of film into a digital format. The Nimbus Data Rescue Project set out on a techno-archeological mission to convert data and images from the NASA Nimbus 1 and 2 satellites that were developed on film into a more manageable digital format. These data extend the satellite record back in time providing the earliest satellite data of polar sea ice extent.

The Nimbus Advanced Vidicon Camera System Visible Imagery L1, HDF5 (NmAVCS1H) is the first data set publicly available from the Nimbus Data Rescue Project. NmAVCS1H consists of black-and-white Advanced Vidicon Camera System (AVCS) images that were acquired by the Nimbus 1 satellite during September 1964 and by Nimbus 2 from May to August 1966. NSIDC researchers and staff scanned the images from archival rolls of 35-mm, black-and-white film. Each HDF5-formatted data file contains an array of 8-bit grayscale values, estimates of the latitude and longitude for each pixel, a grayscale calibration map, and a non-data/data quality mask. Browse images are also available.

For a detailed description of the data see the NmAVCS1H documentation.

To obtain the NmAVCS1H data see the Order Data Web page.

The Nimbus Data Rescue Project was a collaboration between the Lunar Orbiter Image Recovery Project (LOIRP) at NASA Ames Research Park, and NSIDC. For more of the project’s history and development see our Monthly Highlights: Glimpses of Sea Ice Past article and the Nimbus Data Rescue Project Web page.