NSIDC's State of the Cryosphere provides an overview of the status of snow, ice, and permafrost as indicators of climate change. This site provides time-series data for Northern Hemisphere snow cover, mountain glacier fluctuations, sea ice extent and concentration, changes in ice shelves, and global sea level. It also provides a snapshot of current permafrost conditions.

Image credits clockwise from top left: Formosat image of icebergs © 2008 Dr. Cheng-Chien Liu, National Cheng-Kung University and Dr. An-Ming Wu, National Space Organization, Taiwan; photo of ptarmigan tracks by Andrew Slater, NSIDC; photo of James Ross Island by Rob Bauer, NSIDC; International Space Station astronaut photo of Pared Norte Glacier courtesy NASA.

Introduction: Are global temperatures rising?

Northern Hemisphere Snow: What satellite sensors are telling us about snow cover

Glaciers: Mountain glacier fluctuations

Permafrost and Frozen Ground: Insights from a Northern Hemisphere map and field observations

Sea Ice: What satellite sensors are telling us about global sea ice extent and concentration

Ice Shelves: Rapid response to climate change

Ice Sheets: Is ice sheet mass changing?

Sea Level: Is global sea level rising?

Scientific References

NSIDC Data via Google Earth
Download NSIDC data (KML file, 5.2 KB) for viewing NSIDC data in Google Earth (includes links to snow and ice, permafrost and glacier data sets). For details and instructions, see View NSIDC Data on Virtual Globes: Google Earth.

State of the Cryosphere reviews in Science
Volume 306, Issue 5700 (http://science.sciencemag.org/content/306/5700/netwatch)
Volume 288, Issue 5474 (http://science.sciencemag.org/content/288/5474/netwatch)
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