Changes in the cryosphere among other things, challenge the stability of our present time, i.e., the Holocene - a 10,000-year era that followed the retreat of glaciers from mid-latitudes. The shrinking of the cryosphere has implications for water availability, food security, energy and public health, globally. Ultimately, potential changes in thermohaline circulation and extension of polar ice caps are the greatest threats to our society.

Sea-ice can be monitored from space. For example the ice-extent in the Arctic, directly associated to the intensity of the thermohaline circulation in the Atlantic, can be assessed using remote sensing.

More generally, Sea Ice Index consists of graphics showing trends and anomalies in monthly mean Arctic and Antarctic sea ice concentration and extent. The NSIDC Near-Real-Time DMSP SSM/I Daily Polar Gridded Sea Ice Concentrations and the DMSP SSM/I Daily and Monthly Polar Gridded Sea Ice Concentrations data sets are used to generate the monthly mean, trend, and anomaly images so that users of the product can monitor monthly mean ice conditions. The product is intended to illustrate sea ice conditions, and to inform users with general questions about recent ice concentration and extent.

Global Snow coverage can be monitored from space as well as sea ice temperature (the animated example is provided by NASA from Sept. 2002 until May 2003).