A worker ties together slabs of salt extracted from the Danakil Depression in northern Ethiopia April 22. Once the caravan find a suitable place to mine salt, they extract, shape and pack as many salt slabs as possible before starting their two-day journey to the town of Berahile. The Danakil Depression in Ethiopia is one of the hottest and harshest environments on earth, with an average annual temperature of 94 degrees Fahrenheit (34.4 Celsius). For centuries, merchants have travelled there with caravans of camels to collect salt from the surface of the vast desert basin. The mineral is extracted and shaped into slabs, then loaded onto the animals before being transported back across the desert so that it can be sold around the country.

A man walks with his camels through the Danakil Depression, northern Ethiopia April 22. Once the caravan find a suitable place to mine salt, they extract, shape and pack as many salt slabs as possible before starting their two-day journey to the town of Berahile. The Danakil Depression in Ethiopia is one of the hottest and harshest environments on earth, with an average annual temperature of 94 degrees Fahrenheit (34.4 Celsius). For centuries, merchants have travelled there with caravans of camels to collect salt from the surface of the vast desert basin. The mineral is extracted and shaped into slabs, then loaded onto the animals before being transported back across the desert so that it can be sold around the country.

A man lifts slabs of salt onto a truck in the town of Berahile in Afar, northern Ethiopia April 19. The Danakil Depression in Ethiopia is one of the hottest and harshest environments on earth, with an average annual temperature of 94 degrees Fahrenheit (34.4 Celsius). For centuries, merchants have travelled there with caravans of camels to collect salt from the surface of the vast desert basin. The mineral is extracted and shaped into slabs, then loaded onto the animals before being transported back across the desert so that it can be sold around the country.

A man walks on sulphur and mineral salt formations near Dallol in the Danakil Depression, northern Ethiopia on April 22.

A man prepares bars of salt to be sold in the main market of the city of Mekele, northern Ethiopia on April 24.

Farmer Donald O'Reilly searches for sheep or lambs trapped in a snow drift in the Aughafatten area of County Antrim, Northern Ireland on March 26. At least 140,000 homes and businesses in Northern Ireland were left without power over the weekend following heavy snowfall, causing snowdrifts of up to 5 metres (18 feet).

Lambs are pictured on snow covered fields in the hills of Domore, Northern Ireland, on March 26. A Royal Air Force (RAF) helicopter was deployed in Northern Ireland in a bid to reach remote farms where estimates suggest up to 10,000 animals have been buried beneath snowdrifts 20 feet (six metres) high. Thousands of cattle and sheep are already feared to have died in the cold at the height of the lambing season. The bad weather has claimed at least two lives on the British mainland.

Donald O'Reilly rescues a sheep trapped in a snow drift in the Aughafatten area of County Antrim, Northern Ireland on March 26. At least 140,000 homes and businesses in Northern Ireland were left without power over the weekend following heavy snowfall, causing snowdrifts of up to 5 metres (18 feet).

Seven-year-old Achta stands in the door of her family's cooking hut, as her mother prepares dinner over a wood fire by the light of a flashlight, in the village of Louri, in the Mao region of Chad, Nov. 1. Achta's birth seven years ago coincided with the first major drought to hit the Sahel this decade. Climate change has meant that the normally once-a-decade droughts are now coming every few years. The droughts decimated her family's herd. With each dead animal, they ate less. (AP Photo/Rebecca Blackwell)

A woman walks toward a well through clouds of dust raised by cattle in the wadi outside Louri village in the Mao region of Chad, Nov. 1. For generations, the people of this bone-dry region lived off their herds, but climate change has meant that the normally once-a-decade droughts are now coming every few years.

Teacher Djobelsou Guidigui Eloi works with a student at the blackboard in Louri village's school hut in the Mao region of Chad, Nov. 2. Many of the children, unable to read, attempted to pass the lesson by memorizing the sounds and their order on the blackboard. In 2011, 78 boys and girls enrolled in the equivalent of first grade in Chad's school system. Of those children, 42 failed the test to graduate into the next grade, a percentage that almost exactly mirrors the number of children stunted in the county.

Young men walk in the wadi alongside Louri village, in the Mao region of Chad, Nov. 2. Climate change has meant that the normally once-a-decade droughts are now coming every few years, decimating food production.

Health workers measure the height of a boy during a mobile clinic to identify cases of underweight, stunted, or malnourished children, in Michemire, in the Mao region of Chad, Nov. 4.

A boy watches as women pump water from the village borehole in Louri, in the Mao region of Chad, Nov. 3.

A little girl cries as she is weighed as part of a mobile nutrition clinic to examine local children and identify cases of underweight, stunted, or malnourished children, in Michemire, in the Mao region of Chad, Nov. 4.

Children gather under a sole shade tree as they take a break from class outside their schoolhouse made of reeds in the village of Louri, in the Mao region of Chad, Nov. 2.

In this Nov. 1, 2012 photo, 7-year-old Achta, right, walks with her mother Fatme Ousmane in the village of Louri in the Mao region of Chad. Achta's birth seven years ago coincided with the first major drought to hit the Sahel this decade. Climate change has meant that the normally once-a-decade droughts are now coming every few years. The droughts decimated her family's herd. With each dead animal, they ate less. (AP Photo/Rebecca Blackwell)

Seven-year-old Achta looks at the blackboard during class in the village of Louri in the Mao region of Chad, Nov. 2. In this village where malnutrition has become chronic, children have simply stopped growing. In the county that includes Louri, 51.9 percent of children are stunted, one of the highest rates in the world, according to a survey published by UNICEF - more than half the children in the village.

Seven-year-old Achta, her older brother, and their mother Fatme Ousmane share a dinner of rice and meat, a rare treat, leftovers from the recent Eid holiday, in the village of Louri, in the Mao region of Chad. The droughts decimated her family's herd. With each dead animal, they ate less.

The casket of Nelida Gregorio, 89, who died of a heart attack gets lifted up into a gravesite in a flooded cemetery next to the swollen Pampanga River August 15, 2012 in Bulacan, Philippines. A tropical storm hit the Northern Luzon bringing days of wet weather to a region still recovering from massive flooding. According to the Office of Civil Defense the floods have left at least 96 people dead with the flooding effecting up to 2.68 million people, including more than 440,000 fleeing to evacuation centers, in Manila and surrounding provinces.

Family and friends of Nelida Gregorio, 89, who died of a heart attack, mourn her death during a funeral service as they stand in knee deep water in a flooded cemetery next to the swollen Pampanga River on August 15 in Bulacan, Philippines. A tropical storm hit the Northern Luzon bringing days of wet weather to a region still recovering from massive flooding. According to the Office of Civil Defense the floods have left at least 96 people dead with the flooding effecting up to 2.68 million people, including more than 440,000 fleeing to evacuation centers, in Manila and surrounding provinces.

Photo taken on July 17, shows dark clouds of smoke billowing from a wildfire over the town of Tijoco Bajo, on the Spanish Canary island of Tenerife. A forest fire raging on the Spanish island reached the edge of a major tourist park on July 16, spewing thick smoke and red sparks. The fire broke out on July 15, 2012, prompting emergency services to evacuate 90 villagers from their homes overnight, and has spread over 1,800 hectares (2,700 acres), the regional government said.

Trees burn near to a house in a forest fire near Vilaflor, Tenerife, Spain, on Tuesday July 17. Two wildfires in the Canary Islands Tuesday threatened two natural parks in one of the most important tourist archipelago from Spain off the West African coast.

A helicopter tries to extinguish a fire in Vinaflor village, southern Tenerife island, the Canary Islands, Spain, on July 17. The forest fire registred late afternoon on July 15 forced the evacuation of four towns and risking a nature reserve.

People enjoy the warm fine weather besides the sea on March 26 in Bournemouth, England. The Met Office expect today to be the warmest day of the year so far, with temperatures expected to reach about 70 degrees Fahrenheit across many parts of the country.

People enjoy the warm fine weather besides the sea on March 26 in Bournemouth, England.

People enjoy the warm fine weather besides the sea on March 26 in Bournemouth, England.

Inuit hunter Nukappi Brandt steers his small boat as he and his daughter Aaneeraq, 9, scan the water for seals, accompanied by his other daughter Luusi, 8, outside Qeqertarsuaq, Disko Island, Greenland, July 21. Brandt, 49, has been a hunter since age 14, and said roughly 20 years ago, when winter sea ice became too thin to support dogsleds, seal hunting ceased to be a sustainable way of life here.

Inuit hunter Nukappi Brandt aims his rifle to shoot a seal, which dived underwater before he could get off a shot, as his daughter Luusi, 8, keeps low inside their small boat outside Qeqertarsuaq, July 21.

Greenland sled dogs are shown in Qeqertarsuaq, July 21. Some hunters, who relied on winter game to feed their sled dogs, have been unable to continue to support large numbers of dogs, and have been shooting them.

An Inuit fisherman pulls in a fish on a sea filled with floating ice left over from broken-up icebergs shed from the Greenland ice sheet in Ilulissat, Greenland, July 18.

Inuit family members from left, Estrella Brandt, holding her daughter Noelle, Louise Brand and their mother, Rosa Marie Brandt laugh during Rosa Marie's husband's 50th birthday party at their home in Qeqertarsuaq, July 20.

A narwhal whale tusk from a hunt along with miniature replicas of traditional kayaking and hunting tools adorn a wall above a television set inside the home of an Inuit family in Qeqertarsuaq, Greenland. Whales have long been a central part of Inuit life in Greenland, where a regulated subsistence hunt continues to this day.

An Inuit woman sweeps the steps of the church in Qeqertarsuaq, July 20.