This Envisat image shows West Africa around the Gulf of Guinea, with parts of Nigeria to the north and Cameroon to the east visible. Cameroon’s largest city of Douala is located near the Wouri estuary near the center of the image. North of the Wouri estuary, the Mount Cameroon volcano is clearly visible. The island of Bioko is pictured just off the coast.
Reflections of Envisat’s radar signal appear like specks of white throughout the image. They are particularly concentrated around cities such as Malabo on the island, Douala near the Wouri estuary and the populated areas of southern Nigeria. These white specks are the typical appearance of built-up areas in radar images, owing to the multiple reflection of the radar beam by buildings and especially metal constructions.
This image is a compilation of three images from Envisat’s radar, acquired on 6 February, 7 March and 6 April 2012 – just two days before communication with the satellite was lost.
Model of vertical movement across Santorini from January 2011 to present, derived from data from the Envisat and TerraSAR-X missions. Over the past year and a half, parts of Santorini have risen by 14 cm, such as the Kameni islands in the center. Scientists believe that new molten rock has been squeezing up beneath the volcano at a depth of about 4 km, pictured here as a red dot.
This ALOS satellite image shows an area with extensive agricultural use in western Russia, with roads and rivers cutting through the cropland. This area, part of Russia’s Black Earth Region, is about 400 km directly south of Moscow. Many grains are grown here, such as winter wheat and rye.
This image is a compilation of three passes by the Japanese Advanced Land Observation Satellite’s radar on 14 June 2009, 14 September 2009 and 2 August 2010. Each image at the different recording date is assigned a color (red, green or blue) and combined to produce this representation. The colors reveal changes in the surface between the satellite’s passes.
As the U.S. Midwest continues to suffer from near-historic drought conditions, farmers in southwestern Kansas are among the hardest hit. According to the U.S. Department of Agriculture, the area is under "exceptional drought" conditions. This has led to significant reductions of the corn, soybean and pea crops. The two satellite images shown here, obtained about 10 years apart, clearly illustrate the effects of the drought. The top half of this image was acquired on September 6, 2012 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument on NASA's Terra spacecraft; the bottom half of the image was acquired by the Landsat Thematic Mapper on September 15, 2002. Vegetation appears in red, and bare fields are gray or greenish in color. Both images cover an area of 9.3 by 27.9 miles (15 by 44.5 kilometers) and are located near 38.2 degrees north latitude, 100.8 degrees west longitude.
This animation shows Arctic ice cover from 1978 to 2010. The past five years have seen the lowest Arctic sea-ice extent since satellite measurements began in the 1970s.
