Landsat 7, which launched on April 15, 1999, has been continuing to acquire land images worldwide for 16 years. Landsat 5 may hold the Guinness World Record for longest Earth-observing satellite at 28+ years, but Landsat 7 also has an impressive track record. In fact, Landsat 7 has now acquired over 2 million images.
The Oak Ridge National Laboratory DAAC, has just release a Landsat-based forest disturbance history covering the years between 1986 and 2010.
Ice sheets are in perpetual motion, making their way downslope like a river. If the amount of snow that an ice sheet accumulates does not keep pace with its loss to the sea, sea level will rise. As temperatures have climbed, positive feedback loops have led to an accelerated loss of ice sheet sections that touch the sea, but in an unexpected twist to the global warming saga, scientists have just discovered a negative feedback loop that is slowing down the Greenland Ice Sheet sections that end on land—a sliver of good news for sea-level rise.
