Satellite images show the beauty of our terrestrial home — and also provide vital information about its health and future.
From space, Earth is a magnificent sight, splashed with vivid colors, patterns, textures, and abstract forms. But such views can also reveal some of our planet's biggest problems: deforestation, urban sprawl, intensive farming, pollution and natural disasters.
In his new book, Earth from Space, aerial photographer and environmental activist Yann Arthus-Bertrand explores our planet from above. His pictures, along with insights from scientists, activists, and other experts, point out environmental and sociological problems and suggest how satellite imagery can be used to solve them.
Shown here, an image of the Mississippi delta released by NASA two months after the explosion of the Deepwater Horizon oil rig. Red indicates plant cover, which contrasts with the shades of white and blue representing the water.
Oil slicks increase reflection on the surface and therefore appear as brighter white. The image reveals the extent to which hydrocarbon pollution penetrated the delta's marshlands, which are so rich in biodiversity.
A UNESCO World Heritage site, Uluru (as it is called by the Aborigines) or Ayers Rock (to certain Anglophones) is a geological structure standing 1,141 feet tall and 8,200 feet long.
Uluru is located in the heart of a natural park intended to protect it. But the hundreds of thousands of tourists that visit every year disturb both the Aborigines' sacred traditions and the site's fragile biodiversity.
The Great Wall has been on UNESCO's World Heritage List since 1987. The largest architectural structure in the world, it is 19.6–22.9 feet tall and approximately the same across — generally, less than 32 feet.
Its length has been reevaluated several times. In June 2012, the Chinese authorities announced their latest estimate of its length as being 13,170 miles — versus the approximate 4,038 miles reported just a few years earlier...
Approximately 62 miles southeast of Riyadh, the Slamiyah and Dilam oases combine traditional and modern irrigation methods.
The remnants of former palm groves are visible, concentrated right next to the road, surrounded by the circles typical of aspersion irrigation zones: Pivots with ranges of approximately 650 feet provide water to grain plots over an area of approximately 15 square miles.
Bombetoka Bay, the Betsiboka River's sludgy estuary, spans some 6 miles on Madagascar's west coast.
Alluvial islands stretch out in the direction of the current, preceded and extended by sandbanks; they are partially covered by mangrove trees, seen in red in this image.
In the surrounding area, the heavily cleared forest gives way to brush and cassava and rice plantations.
Here we see a vast alluvial cone between the Altun and Kunlun mountains on the southern edge of the Taklamakan Desert.
Formed by the draining of water from the two neighboring mountains, this cone is 37 miles long and 34 miles wide. Its western part, in light blue, is considered active, because it is continuously irrigated.
Flora, seen in red at the top left of the image, can therefore develop; local farmers cultivate small plots of land there.
Over the last thirty years, Saudi Arabia has drilled its soil in search of a resource far more precious than oil: water. The Wadi as-Sirhan Basin's engineers and farmers have used little-known reservoirs to farm grains, fruits, and vegetables in the Saudi desert.
This artificially colored series of images taken in 1987, 1991, 2000, and 2012 shows farming's evolution in the basin. Recently planted surfaces are in green, dry vegetation and fallow land are rust-colored, and dry and bare surfaces (principally desert) are pink and yellow.
No one knows how much water lies under the desert; estimates vary from 60 to 208 cubic miles. Hydrologists have stated that, from an economic perspective, it will only be realistic to pump this resource for a period of fifty years.
The deadly hostage crisis perpetrated by Islamist terrorists on the Algerian gas plant of Tiguentourine took place 25 miles west of the city of In Almenas.
This picture, taken by the SPOT-6 satellite on January 8, 2013, about one week before the crisis, is an example of satellites' potential use for military or security intelligence.
On the left of the shot, you can see the storage tanks of a former oil refinery. To the right, you can distinguish the Sonatrach company's residential base, outlined in black, and farther east, the Y-shaped airfield. The two landing strips, 1.2 miles and 1.8 miles long, respectively, provide a sense of scale.
The city of Angkor Wat was the capital of the Khmer kingdom from the ninth to the fifteenth century. Today, the site is on the UNESCO World Heritage List and includes the remains of temples and a vast network of canals, ornamental lakes, and dikes stretching over approximately 150 square miles.
A NASA study conducted in 2007 used aerial sensors and satellites to show that, at its peak, Angkor extended over more than 380 square miles and had more than one million inhabitants.
The grid patterns of fields and pastures borders the majestic whirlpools of the Mississippi, which boasts the largest hydrographic basin in North America.
Numerous oxbow lakes underline the river's meanders south of Memphis, Tennessee, at the border of Arkansas and Mississippi.