These pictures illustrate the importance of reducing greenhouse emissions and curbing the flow of harmful pollutants into the environment.
Here, a woman collects a sample of the red polluted water flowing from a sewer into the Jian River in Luoyang, north China's Henan Province. The river developed this apocalyptic look after two illegal dye workshops dumped red dye into the city's storm water pipe network.
In December 2016, a child in Jakarta, Indonesia overlooks a duct where residents have been dumping trash for decades.
The Eiffel Tower is seen in through a haze of fog and pollution in Paris in January 2017.
A boy wears a mask as he walks along a road in Beijing in January 2017. China’s law that taxes pollution ignores carbon dioxide, one of the major contributors to global warming.
Heavy air pollution in cities across China routinely exceeds World Health Organization guidelines.
Plastic bags and other trash litter the shoreline of Manila Bay in the Philippines as environmental activists and volunteers attempt to collect them, calling for a ban on the use of plastic bags.
Hong Kong’s skyline is shrouded in a haze of pollution in January 2017. Air pollution has risen to dangerous levels in Hong Kong, creating health risks.
People salvage dead fish from a river in Wuhan, China, after excessive ammonia nitrogen density in the water caused the animals to die en masse along a 25 mile stretch.
Sao Paulo, Brazil
Trash is seen on the polluted Pinheiros River in Sao Paulo, Brazil in January 2017.
Orange water runs out of a drain near the Buena Vista copper mine, in the state of Sonora, Mexico on August 13, 2014.
Five days earlier, 40,000 cubic meters of sulfuric acid leaked from the drain, seriously polluting the Sonora River and causing an eerie orange stain along a 37-mile stretch of water. The spill left more than 20,000 people without drinking water.
Near windless conditions trapped exhaust fumes, choking cities in France. This photo was taken the night before a driving restriction went into effect, as part of anti-pollution measures, in January 2017 in Lyon, France.
Henan Province, China
A woman gapes at the red polluted water flowing from a sewer into the Jian River in Luoyang, north China’s Henan province.
Air pollution reached dangerously high levels in Pristina, Kosovo, at the end of 2016.
Chinese tourists wear face masks while walking past the Forbidden City as heavy air pollution shrouds Beijing in 2015.
Rio de Janeiro, Brazil
Tons of dead fish float on the waters of the Rodrigo de Freitas Lagoon in Rio de Janeiro, Brazil.
A woman fixes a protective mask on a baby during an extremely polluted day in Baoding, China, November 30, 2015.
Baoding, which neighbors Beijing, was deemed the most polluted city in China for the first half of 2015, according to the country’s Ministry of Environmental Protection.
Ao Phrao Beach, Thailand
A shovel sits in oil-covered sand at Ao Phrao Beach in Thailand, as volunteers work to clean up the area after a major oil slick hit the island of Ko Samet in July 2013.
Environmentalists accused a Thai energy firm of understating the extent of the major pipeline leak, as tourists fled the island and the navy warned the oil slick might reach the mainland.
Hebei Province, China
Smoke billows from a steel factory in the industrial province of Hebei. China’s government has set 2030 as a deadline for the country to reach its peak for emissions of carbon dioxide, the gas that scientists and environmentalists cite as the primary cause of climate change.
A partial view of the city of Lyon, France, through a haze of pollution in January 2017.
Residents ride in heavy smog in January 2017 in Zhengzhou, China.
An Indian child searches through mud for coins and other items of value along the polluted banks of the River Ganges at Sangam in Allahabad.
A Chinese tourist wears a face mask in Tiananmen Square as heavy air pollution shrouds Beijing.
Trash clogs up a polluted canal at the edge of Beijing. As of March 2012, two-thirds of Chinese cities failed to meet the air-quality standards based on the pollutants most harmful to health.
People wearing protective masks ride motorcycles in the night during a heavily-polluted day in Beijing, November 30, 2015.
An Indian boy watches smoke rise from a warehouse in New Delhi.
Buildings in Lianyungang, China, are shrouded in a heavy smog that disturbed traffic, worsened air pollution, and forced the closure of schools for more than a week.
A woman cleans a glass panel on a residential building during a hazy day in Shanghai, China, November 30, 2015.
Boats pass along the Huangpu River next to the financial area of the Pudong New District amid heavy smog in Shanghai, China, November 30, 2015.