A fire burns in the exclusion zone around the Chernobyl nuclear power plant, outside the village of Rahivka, Ukraine April 5, 2020. Picture taken April 5, 2020. REUTERS/Yaroslav Yemelianenko

Smoke rises from a forest fire in the exclusion zone around the Chernobyl nuclear power plant, outside the village of Rahivka, Ukraine April 5, 2020. Picture taken April 5, 2020. REUTERS/Yaroslav Yemelianenko

Algae are seen in a fishing net near Mekong river bank outside Nong Khai, Thailand January 10, 2020. REUTERS/Soe Zeya Tun

Algae are seen in a fishing net on the Mekong river bank outside Nong Khai, Thailand January 10, 2020. REUTERS/Soe Zeya Tun

A camp staff feeds Ayeyar Sein, a four-month-old baby elephant who lost her parents to poachers, after her daily wound cleaning in Wingabaw Elephant Camp, Bago, Myanmar, September 30, 2019. Picture taken September 30, 2019. REUTERS/Ann Wang TPX IMAGES OF THE DAY

A tract of the Amazon jungle burns as it is cleared by loggers and farmers in Porto Velho, Brazil August 24, 2019. REUTERS/Ueslei Marcelino

The carcass of a cow is seen at a ranch as the Caribbean nation endures its worst drought in 30 years, in Santiago Rodriguez, Dominican Republic March 16, 2019. Picture taken March 16, 2019. REUTERS/Ricardo Rojas

Students take part in a "youth strike to act on climate change" demonstration in Nice, France, March 15, 2019. REUTERS/Eric Gaillard

A man walks in front of the India Gate shrouded in smog in New Delhi, India, October 29, 2018. REUTERS/Anushree Fadnavis TPX IMAGES OF THE DAY

Tires and other debris are seen in the dried-out riverbed of the Cijevna River, in the village Dinosa, near Tuzi, Montenegro, October 20, 2018. REUTERS/Stevo Vasiljevic

Debris is seen in the dried-out riverbed of the Cijevna River, in the village Dinosa, near Tuzi, Montenegro, October 20, 2018. REUTERS/Stevo Vasiljevic

A view of dried-out riverbed of the Cijevna River, in the village Dinosa, near Tuzi, Montenegro, October 20, 2018. REUTERS/Stevo Vasiljevic

A view of dried-out riverbed of the Cijevna River, in the village Dinosa, near Tuzi, Montenegro, October 20, 2018. REUTERS/Stevo Vasiljevic

A view of dried-out riverbed of the Cijevna River, in the village Dinosa, near Tuzi, Montenegro, October 20, 2018. REUTERS/Stevo Vasiljevic

Waves crash on stilt houses along the shore due to Hurricane Michael at Alligator Point in Franklin County, Florida, U.S., October 10, 2018. REUTERS/Steve Nesius TPX IMAGES OF THE DAY

A general view of Cheruthoni dam with one open gate is seen in Idukki, Kerala, India, September 5, 2018. REUTERS/Sivaram V SEARCH "SIVARAM DAMS" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. TPX IMAGES OF THE DAY.

A man rides his motorbike over a damaged bridge in Idukki, Kerala, India, September 6, 2018. REUTERS/Sivaram V SEARCH "SIVARAM DAMS" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES.

Idukki Arch Dam is seen in Kerala, India, September 5, 2018. REUTERS/Sivaram V SEARCH "SIVARAM DAMS" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES.

Waves crash on stilt houses along the shore due to Hurricane Michael at Alligator Point in Franklin County, Florida, U.S., October 10, 2018. REUTERS/Steve Nesius

Two chairs are seen at the bottom of the sea off the island of Thasos, Greece, August 29, 2018. Picture taken August 29, 2018. REUTERS/Stelios Misinas

Metal waste is seen at the bottom of the sea off the island of Thasos, Greece, August 29, 2018. Picture taken August 29, 2018. REUTERS/Stelios Misinas

An anchor and other metal waste are seen at the bottom of the sea off the island of Thasos, Greece, August 29, 2018. Picture taken August 29, 2018. REUTERS/Stelios Misinas

An aerial view shows partially submerged road at a flooded area in the southern state of Kerala, India, August 19, 2018. REUTERS/Sivaram V TPX IMAGES OF THE DAY

An aerial view shows partially submerged road at a flooded area in the southern state of Kerala, India, August 19, 2018. REUTERS/Sivaram V

An aerial view shows partially submerged houses at a flooded area in the southern state of Kerala, August 19, 2018. REUTERS/Sivaram V

An aerial view shows partially submerged buildings at a flooded area in the southern state of Kerala, India, August 19, 2018. REUTERS/Sivaram V

An aerial view shows partially submerged houses at a flooded area in the southern state of Kerala, India, August 17, 2018. REUTERS/Sivaram V

An aerial view shows partially submerged houses at a flooded area in the southern state of Kerala, India, August 17, 2018. REUTERS/Sivaram V

A sunflower blooms in between dried-out ones during hot summer weather on a field near the village of Benken, Switzerland August 6, 2018. Picture taken with a fisheye lens. REUTERS/Arnd Wiegmann TPX IMAGES OF THE DAY

Dried-out sunflowers stand during hot summer weather on a field near the village of Benken, Switzerland August 6, 2018. REUTERS/Arnd Wiegmann

Fish, found dead in the Rhine River, lie in a box in Neuhausen am Rheinfall, Switzerland August 6, 2018. REUTERS/Arnd Wiegmann

A sunflower blooms in between dried-out ones during hot summer weather on a field near the village of Benken, Switzerland August 6, 2018. Picture taken with a fisheye lens. REUTERS/Arnd Wiegmann

Cows walk through a partially dried-out riverbed during hot weather near the mountain resort of Flims, Switzerland August 5, 2018. REUTERS/Arnd Wiegmann

A woman stands on a road flooded by waters from the River Ebro, following heavy rains and snow melt in Castejon, Spain, April 13, 2018. REUTERS/Vincent West

A man stands on a road flooded by waters from the River Ebro, following heavy rains and snow melt in Castejon, Spain, April 13, 2018. REUTERS/Vincent West

Trees are reflected in flood waters from the River Ebro, following heavy rains and snow melt in Tudela, Spain, April 13, 2018. REUTERS/Vincent West

An American flag stands in front of a home destroyed after a wildfire tore through Santa Rosa, California, U.S., October 15, 2017. REUTERS/Jim Urquhart TPX IMAGES OF THE DAY

Firefighters work to control a wildfire in Sonoma, California, U.S., October 14, 2017. REUTERS/Jim Urquhart TPX IMAGES OF THE DAY

An aerial shows damage caused by wildfires in Santa Rosa, California, U.S October 11, 2017. Picture taken October 11, 2017. REUTERS/DroneBase TPX IMAGES OF THE DAY

An American flag hangs from a tree in a neighborhood destroyed by wildfire in Santa Rosa, California, U.S., October 12, 2017. REUTERS/Jim Urquhart TPX IMAGES OF THE DAY

Houses damaged by a mudslide is seen after that the Storm Nate affected the country in outskirts of San Jose, Costa Rica October 6, 2017. REUTERS/Juan Carlos Ulate TPX IMAGES OF THE DAY

A man tries to salvage a table belonging to his restaurant before the arrival of Hurricane Maria in Punta Cana, Dominican Republic, September 20, 2017. REUTERS/Ricardo Rojas TPX IMAGES OF THE DAY

Rubbish lie on the water as destroyed buildings are seen following Hurricane Irma in Cul de Sac, Saint Martin island, France September 15, 2017. REUTERS/Andres Martinez Casares TPX IMAGES OF THE DAY

A bird covered in oil that leaked from a small oil tanker that sank on September 10, tries to stay afloat near the shores of Salamina island, Greece, September 12, 2017. REUTERS/Giorgos Moutafis TPX IMAGES OF THE DAY

The Sam Houston Parkway is still completely covered with Harvey floodwaters in Houston, Texas September 1, 2017. REUTERS/Rick Wilking TPX IMAGES OF THE DAY

A firefighting helicopter makes water drop as a wildfire burns near the village of Metochi, north of Athens, Greece, August 15, 2017. REUTERS/Giorgos Moutafis TPX IMAGES OF THE DAY

Firefighters try to control a forest fire at Lustica peninsula near Tivat, Montenegro July 17, 2017. REUTERS/Stevo Vasiljevic TPX IMAGES OF THE DAY

A motorhome is flooded in Marysville, California, after an evacuation was ordered for communities downstream from the dam in Oroville, California, U.S., February 14, 2017. REUTERS/Jim Urquhart

A cemetery is flooded in Marysville, California, after an evacuation was ordered for communities downstream from the dam in Oroville, California, U.S., February 14, 2017. REUTERS/Jim Urquhart

A cemetery is flooded in Marysville, California, after an evacuation was ordered for communities downstream from the dam in Oroville, California, U.S., February 14, 2017. REUTERS/Jim Urquhart

Fog partially covers wind turbines on a hill near Tudela, northern Spain February 14, 2017. REUTERS/Susana Vera

Cows belonging to Samburu tribesmen graze near bushfire which is set up according to witnesses by cattle herders in Mugui Conservancy, Kenya, February 11, 2017. REUTERS/Goran Tomasevic

Clothes hang in an area destroyed by Hurricane Matthew in Les Anglais, Haiti, October 11, 2016. REUTERS/Andres Martinez Casares TPX IMAGES OF THE DAY

People walk on the road as rain falls during Hurricane Matthew in Les Cayes, Haiti, October 4, 2016. REUTERS/Andres Martinez Casares TPX IMAGES OF THE DAY

Trees sway with the wind during Hurricane Matthew in Les Cayes, Haiti, October 4, 2016. REUTERS/Andres Martinez Casares TPX IMAGES OF THE DAY

View of the flooded river-side of the River Seine near the Eiffel tower in Paris, France, after days of almost non-stop rain caused flooding in the country, June 3, 2016. REUTERS/Philippe Wojazer - TPX IMAGES OF THE DAY

A mobile home park lies flooded as the Brazos River approaches its crest in Richmond, Texas, U.S. May 31, 2016. Precipitation was expected to intensify over the weekend as moisture from tropical depression Patricia, which struck the Pacific coast of Mexico on Friday as a very powerful hurricane, meets with a storm system coming from the west and over Texas. REUTERS/Daniel Kramer

Dead fish are seen as Lake St Lucia is almost completely dry due to drought conditions in the iSimangaliso Wetland Park, northeast of Durban, South Africa February 25, 2016. REUTERS/Rogan Ward TPX IMAGES OF THE DAY

A combination picture shows a Sarajevo TV tower as smog blankets Sarajevo, Bosnia and Herzegovina December 28, 2015 (top) and at the same place January 12, 2016. REUTERS/Dado Ruvic TPX IMAGES OF THE DAY

French President Francois Hollande attends "The Climate Challenge and African solutions" event during the World Climate Change Conference 2015 (COP21) at Le Bourget, near Paris, France, December 1, 2015. REUTERS/Philippe Wojazer