An update from Mark about the Proba satellite: http://www.wired.com/wiredscience/2013/07/new-global-vegetation-map/.
Proba-V is a Belgian-built satellite - the latest in the European Space Agency’s PROBA series of small satellites and will take over vegetation monitoring duties from the Spot-4 and Spot-5 satellites, which are at the end of a 15-year mission. The Proba-V satellite is barely bigger than a washing machine. It was launched just two months ago has already made a wall-to-wall map of the world’s vegetation.
It orbits the Earth 14 times a day, covering the entire globe every two days with 100m resolution imager. Every 10 days, a new 200,000 megapixel image of the world’s vegetation is produced.
Background: the current Vegetation-1 and Vegetation-2 instruments onboard the SPOT 4 and SPOT 5 satellites will only be available till May 2014. For almost 15 years now, these instruments have daily monitored and mapped the worldwide vegetation, thus providing essential information on crop yields, droughts, desertification, changes in the type of vegetation, deforestation, etc. to an ever extending user community.