This image over a remote area in southern Iran was acquired by Japan’s ALOS satellite on 10 December 2009.
To the west we can see the waters of the Strait of Hormuz, which lies between the Gulf of Oman to the south and Persian Gulf to the north. The brown areas along the coast are sediments carried from rivers that flow only after erratic rainfall in the interior, usually in the winter months.
On the whole, the area pictured is extremely arid, as evident by the lack of vegetation. But in the upper left and slightly inland, we can see a green area that appears to be standing water from a human-made dam on the river.
The dark zones along the coast are wetlands at the deltas of the Rud-e-Gaz and Rud-e-Hara rivers. This extensive complex of tidal mudflats, creeks, salt marshes, mangroves, sandbanks and offshore islands is an important site for wintering waterbirds.
This is just one of the over 2000 sites worldwide considered to be wetlands of international importance by the Ramsar Convention, an intergovernmental treaty for the sustainable use of wetlands.
Dedicated ESA programs assist the convention by providing satellite data to be used to monitor these important areas. With their repeating global coverage, satellites are ideal for imaging remote areas that require monitoring – like the wetland pictured here.
This picture is featured on the Earth from Space video program.
Image credit: JAXA/ESA
This satellite image was acquired over the edge of a salt marsh near the northeast Caspian Sea in southwestern Kazakhstan.
The Caspian Sea (not pictured) is the largest inland body of water by surface area. With an average depth of about 5 m, the northern part of the Caspian is very shallow, while the central and southern parts of the sea are much deeper. The salinity of the waters also change from north to south, being more saline in the northern, shallow waters and less in the south.
The salt marsh in the upper section of this image was once a gulf of the Caspian Sea, but fluctuating sea levels over the last decades cause it to be cut off occasionally from the main body of water and even dry up. In this image, it appears that the water has evaporated, leaving behind a white salt crust.
Rock formations dominate the central part of the image, while a plateau stretches south and east (not pictured). The visible shapes in combination with the dark color of the rocks may indicate that they are volcanic, with water erosion evident in the finger-like runoff patterns.
The grey rim between the land and salt pan comes from the sedimentary runoff from the land mixing with the saltwater. When the marsh is dry, a greyish color is left behind.
The arid climate in this region makes it easy to acquire optical imagery from satellites, without the obstruction of visibility by clouds.
This image was acquired on 6 November 2012 by the Korea Aerospace Research Institute’s Kompsat-2 satellite and is featured on the Earth from Space video program.
Photo credit: KARI/ESA
