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Satellite Eye on Earth January 2017 in pictures

A sacred Tibetan lake, a crack in the Antarctic ice shelf and deforestation in Cambodia are among images captured by Nasa and the ESA this month

Yamzho Yumco (Sacred Swan) Lake is one of the three largest sacred lakes in Tibet. It is surrounded by snow-capped mountains and is highly crenellated with many bays and inlets. The lake is home to the Samding monastery which is headed by a female reincarnation, Samding Dorje Phagmo. The image covers an area of 49.8km by 60km. Aster images map and monitor the changing surface of our planet, such as glacial advances and retreats; potentially active volcanoes; crop stress; cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

Credits:
Photograph: ISS/Nasa

This distinctive checkerboard pattern lies alongside the Priest river in northern Idaho. The photograph was taken just before sunset, so some mountainsides glow while others are covered in long shadows because of the low sun angle. The squares appear to be the result of forest management. The land here is now managed for wildlife and for timber harvesting. The white patches reflect areas with younger, smaller trees, where winter snow cover shows up brightly to the astronauts. Dark green-brown squares are parcels of denser, intact forest. The checkerboard is used as a method of maintaining the sustainability of forested tracts while still enabling a harvest of trees. The Priest river, winding through the scene, is bordered on both sides by a forest buffer that can serve as a natural filtration system to protect water quality. For nearly a century, the river was used to transport logs. Its function changed in 1968 when the rivers main stem was added to a list of wild and scenic rivers in order to preserve its outstanding natural, cultural, and recreational values in a free-flowing condition for the enjoyment of present and future generations.

Credits:
Photograph: Modis/Terra/Nasa

According to weather forecasts, Denmark was in line to be hit with strong winds, sub-zero temperatures, and precipitation from 4-7 January. Heavy flooding was expected in parts of the west coast, while Jutland and Bornholm were in line for sleet and snow. In this image, a layer of white lies over northern Jutland in the north-west, and additional streaks of snow can be seen as far south as Germany. A bank of cloud, likely part of the storm system, hangs over the blue waters of Skagerrak a strait that lies between the south-east coast of Norway, the south-west coast of Sweden, and Denmarks Jutland peninsula.

Credits:Pleiades/ESA
Photograph: Pleiades/ESA

How do you deliver supplies to one of the most remote research stations on Earth? Put the equipment and food on skis and pull them by tractor across the ice and snow in a long caravan. The convoy of supplies can be seen on the 1,000km trek from Dumont dUrville on the Antarctic coast to Concordia research station. The traverse across Antarctica takes 10 days, climbing more than 3,000 metres to reach Concordias plateau. Pulled by heavy-duty tractors, the caravans carry up to 300 tonnes of fuel, food and heavy equipment in 300 metre-long convoys organised by Frances IPEV polar institute. Once at Concordia, three days are spent unpacking and preparing for the return trip to the coast, which generally takes two days less because it is downhill most of the way.

Concordia sits on a plateau 3,200 metres above sea level. Temperatures can drop to 80C in winter when the sun does not rise above the horizon, forcing the crew to live in isolation without sunlight for four months of the year. For ESA, the isolation and extreme weather offer interesting parallels with spaceflight. Each year an ESA-sponsored medical doctor joins the crew of the ItalianFrench station to monitor and run experiments.

Credits:
Photograph: Sentinel-2A/ESA

Snow-covered St Petersburg on the Neva bay may appear to be in black and white, but it is in fact in true colour the snow and lack of vegetation during winter lend very little colour to the scene. One of the most prominent features is the large area of ice and snow covering the water.

Looking closer to the lower-central part of the image, we can see where icebreakers have created a straight route to and from St Petersburgs port. The boats leaving the port continue west following a channel through the St Petersburg dam south of Kotlin Island and into the Gulf of Finland. There are five other breaks along the northern stretch of the dam without ice because the flowing water prevented freezing. The 25km-long dam complex protects the city from storm surges and also acts as a bridge from the mainland to Kotlin Island. On the right, the Neva flows through the centre of St Petersburg Russias second largest city. Sometimes dubbed the Venice of the North for its numerous canals and more than 400 bridges, the city dates back to 1703 and was built by Tsar Peter the Great. Today, St Petersburg is a Unesco world heritage site.

Credits:
Photograph: VIIRS/Suomi NPP/Nasa

Milky, grey smog shrouds many of the valleys and lowlands of eastern China. The brightest, whiter areas (left, top, and bottom edges) are likely clouds or fog. Outbreaks of smog and haze, like this, tend to occur during the winter because of temperature inversions. Air naturally cools as it rises in altitude; but during an inversion, warm air masses settle over a layer of cool air near the surface. The warm air acts like a lid and traps gases and pollutants near the surface, especially in basins and valleys.

Many of the particles in the haze are sulphate aerosols produced by burning coal. Coal supplies a majority of Chinas energy, and the northern half of the country uses coal widely to heat buildings in the winter. In addition to emitting carbon dioxide, coal fires release sulphur dioxide, a gas that combines with water vapour to make small droplets and crystals of sulphuric acid and other sulphates, which can be detrimental to health.

Credits: OLI/Landsat 8/Nasa
Credits: OLI/Landsat 8/Nasa

Several days of heavy rainfall swamped much of southern Thailand in January. While monsoon-related floods are common in the region, the wet season usually ends in November. Much of the tan and yellow colour on the landscape is sediment-laden flood water near the Pra river. For comparison, the second image shows the same area on 2 February 2014, when waters were lower. The rainfall was some of the most severe to hit Thailand in three decades, according to Thai authorities. More than 300,000 homes were affected, and damage to infrastructure was widespread. At least 36 people died.

Credits:
Photograph: ISS/Nasa

A photograph of a variety of agricultural patterns near an oasis in eastern Libya, one of the most remote places in Africa, more than 900km (560 miles) from the nearest major city. The cluster of buildings, roads, and small farming operations near the top of the photo is the town of Al Jawf. Each farming pattern in the image is related to different irrigation methods. The honeycombs in the centre are what remain of the first planned farming method in the Libyan desert, implemented about 1970. The large circles (about 1km wide) of centre-pivot irrigation systems (lower left) replaced the honeycombs in order to conserve water. The grid system (upper left) is perhaps one of the oldest known to planned agriculture, but it is still used alongside the more modern patterns.

Near Al Jawf, the oasis is covered in lush green gardens and palm trees that survive due to pumping from the largest known fossil water aquifer in the world: the Nubian Sandstone Aquifer. More than 20,000 years ago, the Saharan landscape was wet and heavy rainfall continuously refilled the aquifer. Today the region receives less than 0.1in of rain a year, making this aquifer a non-renewable resource. An agreement was recently hashed out between Libya and the UN Food and Agriculture Organisation to improve food security in the region by developing the countrys agriculture industry. This means the use of fossil water will continue, and the agricultural patterns we see today are likely to survive for years to come.

Credits:
Photograph: Planet

The winter landscape in Brussels complements the red clay roofs of the historic Quartier des Squares (centre) and the white tops of the Royal Museum of the Armed Forces (centre right).

Credit:
Photograph: Sentinel-2/ESA

An area over the western end of the state of Texas is rather devoid of colour owing to the landscapes sparse vegetation cover. Some colour appears along the rivers and streams where plants thrive more easily. In the upper left, large circles of agriculture from central-pivot irrigation systems appear green. Centre left, one area appears orange where the land may have a different mineral content. On the upper-right side, we can see a cluster of hills of the Sierra Madera crater, formed less than 100m years ago when a meteorite hit Earth. In the lower-right corner, we can see a network of oil wells connected via a spiderweb-like structure of supply roads. Underground oil reservoirs usually stretch across large areas, and multiple wells are positioned over the reservoirs to best exploit the natural resource. Texas is the top crude oil-producing state in the US, accounting for about a third of the countrys output.

Credits: Copernicus Sentinel-1/ESA
Credits: Copernicus Sentinel-1/ESA

A crack in the Larsen-C ice shelf on the Antarctic peninsula first appeared several years ago, but recently it has been lengthening faster than before. The satellites show that the fissure has opened about 60km since January last year. And, since the beginning of this January, it has split a further 20km so that the 350 metre-thick shelf is held only by a thread. The crack now extends around 175km. When the ice shelf calves, this iceberg will be one of the largest ever recorded. Exactly how long this will take is difficult to predict. The neighbouring Larsen-A and Larsen-B ice shelves suffered a similar fate with dramatic calving events in 1995 and 2002, respectively. These ice shelves are important because they act as buttresses, holding back the ice that flows towards the sea.

Credits:
Photograph: ISS/Nasa

This panorama shows nearly the full length of Lake Powell, the reservoir on the Colorado river in southern Utah and northern Arizona. At full capacity, the reservoir impounds 24,322,000 acre-feet of water, a vast amount that is used to generate and supply water to several western states, while also aiding in flood control for the region. It is the second largest reservoir by maximum water capacity in the US (behind Lake Mead).

Green forests indicate two high places in the image that are cooler and receive more rain than the dry, low country surrounding the lake. The isolated Navajo mountain is a sacred mountain of the Native American Navajo tribe and rises to 3,154 metres (10,348ft). The long, narrow Kaiparowits Plateau rises nearly 1,200 metres from Lake Powell to an elevation of more than 2,300 metres. More than 80km (50 miles) long, the plateau gives a sense of horizontal scale. The region draws nearly 2 million people every year, even though it is remote and has few roads. Most of the area in view is protected as part of the Glen Canyon national recreation area and the Grand Staircase-Escalante national monument the largest area of protected land in a US national monument.

Credits:
Photograph: Planet

The Moroccan city of Nador is sheltered from the Mediterranean by Mar Chica, a sandy saltwater lagoon. Mar Chica has a shallow maximum depth only 8 metres allowing us to see the ebb and flow of tides clearly from space.