A pelican takes a dip in a pond at Dvur Kralove Zoo, Czech Republic, June 12, 2019. REUTERS/David W Cerny 

A pelican splashes water inside an enclosure at the Moscow Zoo on a hot summer day in the capital Moscow, Russia June 7, 2019. REUTERS/Tatyana Makeyeva 

Hay rolls damaged by rain and flood waters that cannot be moved due to muddy conditions lie soaked on a farm after a series of storms across the central plains in Alva, Oklahoma, U.S. May 24, 2019. Picture taken May 24, 2019. REUTERS/Gene Blevins 

Hay rolls damaged by flood waters lie soaked on a farm after a series of storms across the central plains in Alva, Oklahoma, U.S. May 24, 2019. Picture taken May 24, 2019. REUTERS/Gene Blevins 

Hay rolls damaged by flooding are set outside a cattle farm after a series of storms across the central plains in Buffalo, Oklahoma, U.S. May 25, 2019. REUTERS/Gene Blevins 

Hay rolls damaged by flood waters that cannot be moved due to muddy conditions lie soaked on a farm after a series of storms across the central plains in Alva, Oklahoma, U.S. May 24, 2019. Picture taken May 24, 2019. REUTERS/Gene Blevins 

Erick Solis (not pictured) irrigates hydroponic lettuce at his house on a small farm in San Jose, Costa Rica May 2, 2019. REUTERS/Juan Carlos Ulate 

A tank is filled with potable water by a municipal employee (not pictured) on the outskirts of Ciudad Juarez, Mexico March 22, 2019. REUTERS/Jose Luis Gonzalez 

A Hindu devotee prays during Huranga, a game played between men and women a day after Holi, at Dauji temple near the northern city of Mathura, India March 22, 2019. REUTERS/Adnan Abidi 

A man bathes at a roadside municipal tap in a market area of Kolkata, India, March 22, 2019. REUTERS/Rupak De Chowdhuri 

A man refreshes himself and his dog at a fountain in Madureira Park in Rio de Janeiro, Brazil March 19, 2019. REUTERS/Ricardo Moraes 

Hindu devotees take part in the religious festival of Holi inside a temple in Nandgaon village, in the state of Uttar Pradesh, India, March 16, 2019. REUTERS/Adnan Abidi 

People watch as large waves crash against the seawall during strong winds at Porthcawl, Britain, March 16, 2019. REUTERS/Toby Melville 

Participants throw toys towards law enforcement officers during a rally held by members of Ukrainian nationalist movements, who demand an investigation into top officials' activities suspected of corruption, near the presidential administration headquarters in Kiev, Ukraine March 16, 2019. REUTERS/Gleb Garanich 

A view of a makeshift camp next to the Moria camp for refugees and migrants, following rainfall on the island of Lesbos, Greece, February 23, 2019. REUTERS/Elias Marcou 

A man dressed as Santa Claus pedals passengers in a rickshaw along Oxford Street, in London, Britain December 23, 2018. REUTERS/Hannah McKay 

Hamish the polar bear emerges from his frozen muddy pond searching for his red ball in the Highland Wildlife Park in Kincraig, Scotland, Britain, December 16, 2018. REUTERS/Russell Cheyne TPX IMAGES OF THE DAY 

Hamish the polar bear emerges from his frozen muddy pond searching for his red ball in the Highland Wildlife Park in Kincraig, Scotland, Britain, December 16, 2018. REUTERS/Russell Cheyne 

Hamish the polar bear plays in a frozen muddy pond in the Highland Wildlife Park in Kincraig, Scotland, Britain, December 16, 2018. REUTERS/Russell Cheyne 

Hamish the polar bear plays in a frozen muddy pond in the Highland Wildlife Park in Kincraig, Scotland, Britain, December 16, 2018. REUTERS/Russell Cheyne 

Purple yams and a pot containing rice noodles placed by villagers are seen at a hot spring attraction in Rucheng county, Hunan province, China December 2, 2018. Picture taken December 2, 2018. To match Insight CHINA-ECONOMY/DEBT-RUCHENG. REUTERS/Shu Zhang 

Cars travel past a weather warning sign on the A9 road near Stirling, in Scotland December 15, 2018. REUTERS/Russell Cheyne 

A doll floats in rainwater at a shelter for migrants, part of a caravan of thousands from Central America trying to reach the United States, in Tijuana, Mexico, November 29, 2018. REUTERS/Adrees Latif 

Tourists take pictures as waves splash at the seafront in Havana, Cuba, November 15, 2018. REUTERS/Alexandre Meneghini TPX IMAGES OF THE DAY 

A woman walks through a snowstorm in Times Square in New York City, New York, U.S., November 15, 2018. REUTERS/Mike Segar 

With the vivid colors of autumn leaves still on the trees, a woman holds her umbrella against an early snowfall on the National Mall in Washington, U.S., November 15, 2018. REUTERS/Kevin Lamarque 

A woman holds an umbrella against the area's first snowfall on the National Mall in Washington, U.S., November 15, 2018. REUTERS/Kevin Lamarque 

A worker waits for visitors outside of the U.S. Capitol in Washington, U.S., November 15, 2018. REUTERS/Leah Millis TPX IMAGES OF THE DAY 

A worker waits for visitors outside of the U.S. Capitol in Washington, U.S., November 15, 2018. REUTERS/ Leah Millis 

Visitors take photographs as it snows outside of the U.S. Capitol in Washington, U.S., November 15, 2018. REUTERS/ Leah Millis 

A fire hose is seen as firefighters battle the Peak fire in Simi Valley, California, U.S. November 12, 2018. REUTERS/Eric Thayer 

Firefighters battle the Peak fire in Simi Valley, California, U.S. November 12, 2018. REUTERS/Eric Thayer 

Wild ducks swim in the icy waters of the Yenisei River with the air temperature at about minus 20 degrees Celsius (minus 4 Fahrenheit) in the Siberian Taiga area outside Krasnoyarsk, Russia, November 12, 2018. REUTERS/Ilya Naymushin 

Wild ducks swim in the icy waters of the Yenisei River with the air temperature at about minus 20 degrees Celsius (minus 4 Fahrenheit) in the Siberian Taiga area outside Krasnoyarsk, Russia, November 12, 2018. REUTERS/Ilya Naymushin 

A wild duck swims in the icy waters of the Yenisei River with the air temperature at about minus 20 degrees Celsius (minus 4 Fahrenheit) in the Siberian Taiga area outside Krasnoyarsk, Russia, November 12, 2018. REUTERS/Ilya Naymushin 

Big-wave surfer Sebastian Steudtner of Germany drops in a large wave at Praia do Norte in Nazare, Portugal November 9, 2018. REUTERS/Rafael Marchante TPX IMAGES OF THE DAY 

People shelter under umbrellas as they walk in St Peter's square at the Vatican, November 5, 2018. REUTERS/Alessandro Bianchi 

A sign directing voters is seen at an early voting polling station in Milwaukee, Wisconsin, U.S. November 4, 2018. REUTERS/Nick Oxford 

A voter leaves a polling station after voting early in Milwaukee, Wisconsin, U.S. November 4, 2018. REUTERS/Nick Oxford 

A man carrying an umbrella crosses a footbridge over a canal during the season's first snowfall in Srinagar November 3, 2018. REUTERS/Danish Ismail 

A seaweed farmer holds a variety of seaweed he grows in Tuaran, Sabah, Malaysia, July 8, 2018. Picture taken July 8, 2018. To match Special Report OCEANS-TIDE/SHRIMP REUTERS/Edgar Su 

A woman walks in the territory of the Kiev Pechersk Lavra monastery on a foggy autumn day in Kiev, Ukraine, October 30, 2018. REUTERS/Valentyn Ogirenko 

A participant runs through a foam bath during the 'Colour My Run' charity fun run on Manoel Island in Valletta's Marsamxett Harbour, Malta October 28, 2018. REUTERS/Darrin Zammit Lupi TPX IMAGES OF THE DAY 

A dog walks through a flooded street after heavy rains caused Paraguay's river to overflow, on the outskirts of Asuncion, Paraguay October 24, 2018. REUTERS/Jorge Adorno 

Raindrops are seen on a heart shaped padlock as it hangs on the fence of Makartsteg bridge in Salzburg, Austria, October 24, 2018. REUTERS/Lisi Niesner 

A water buffalo, owned by Anan Chalermlarb, has a shower before a practice session ahead of Chonburi's annual buffalo race festival in Chonburi province, Thailand October 18, 2018. Picture taken October 18, 2018. REUTERS/Athit Perawongmetha TPX IMAGES OF THE DAY 

The Arab Baths monument is seen flooded after heavy rain and flash floods hit Ronda, southern Spain, October 21, 2018. REUTERS/Jon Nazca 

A flooded field is seen after heavy rain and flash floods hit Campillos, southern Spain, October 21, 2018. REUTERS/Jon Nazca 

A flooded field is seen after heavy rain and flash floods hit Campillos, southern Spain, October 21, 2018. REUTERS/Jon Nazca 

A bird egg is seen on a street after a heavy rain and flash floods hit Campillos, southern Spain, October 21, 2018. REUTERS/Jon Nazca 

A dead rat lies on a street after a heavy rain and flash floods hit Campillos, southern Spain, October 21, 2018. REUTERS/Jon Nazca 

A dead bird lies on a street after a heavy rain and flash floods hit Campillos, southern Spain, October 21, 2018. REUTERS/Jon Nazca 

A man shows a dead bird after a heavy rain and flash floods hit Campillos, southern Spain, October 21, 2018. REUTERS/Jon Nazca 

A dead bird lies on a street after a heavy rain and flash floods hit Campillos, southern Spain, October 21, 2018. REUTERS/Jon Nazca 

A flood level mark is seen inside a house after heavy rain and flash floods hit Campillos, southern Spain, October 21, 2018. REUTERS/Jon Nazca 

A flood level mark is seen as mud stains the entrance of a house after heavy rain and flash floods hit Campillos, southern Spain, October 21, 2018. REUTERS/Jon Nazca 

Lightning streaks are seen during a storm over the Auberge de Castille, the office of the Prime Minister Joseph Muscat, in Valletta, Malta October 19, 2018. REUTERS/Darrin Zammit Lupi TPX IMAGES OF THE DAY 

Lightning streaks are seen during a storm over the Auberge de Castille, the office of the Prime Minister Joseph Muscat, in Valletta, Malta October 19, 2018. REUTERS/Darrin Zammit Lupi 

Hydrocarbon slabs, from an oil spill after two ships collided in the waters off Corsica, October 7, are seen on the Plage de Pampelonne beach near Ramatuelle, France, October 16, 2018. REUTERS/Eric Gaillard 

Hydrocarbon slabs, from an oil spill after two ships collided in the waters off Corsica, October 7, are seen on the Plage de Pampelonne beach near Ramatuelle, France, October 16, 2018. REUTERS/Eric Gaillard