Aerial view of thermopower plant Kakanj, Bosnia and Herzegovina May 17, 2021. Picture taken May 17, 2021.Picture taken with drone. REUTERS/Dado Ruvic 

Coal miners prepare to work in coal mine Abid Lolic in Nova Bila, Bosnia and Herzegovina May 12, 2021. Picture taken May 12, 2021. REUTERS/Dado Ruvic 

Coal miners enter to mine in coal mine Abid Lolic in Nova Bila, Bosnia and Herzegovina May 12, 2021. Picture taken May 12, 2021. REUTERS/Dado Ruvic 

Coal miners prepare to work in coal mine Abid Lolic in Nova Bila, Bosnia and Herzegovina May 12, 2021. Picture taken May 12, 2021. REUTERS/Dado Ruvic 

Coal miners prepare to work in coal mine Abid Lolic in Nova Bila, Bosnia and Herzegovina May 12, 2021. Picture taken May 12, 2021. REUTERS/Dado Ruvic 

A coal miner smiles before working in coal mine Abid Lolic in Nova Bila, Bosnia and Herzegovina May 12, 2021. Picture taken May 12, 2021. REUTERS/Dado Ruvic 

Coal miners smoke before working in coal mine Abid Lolic in Nova Bila, Bosnia and Herzegovina May 12, 2021. Picture taken May 12, 2021. REUTERS/Dado Ruvic 

Coal miners enter to mine in coal mine Abid Lolic in Nova Bila, Bosnia and Herzegovina May 12, 2021. Picture taken May 12, 2021. REUTERS/Dado Ruvic 

Coal miners sit before working in coal mine Abid Lolic in Nova Bila, Bosnia and Herzegovina May 12, 2021. Picture taken May 12, 2021. REUTERS/Dado Ruvic 

Coal miners sit before working in coal mine Abid Lolic in Nova Bila, Bosnia and Herzegovina May 12, 2021. Picture taken May 12, 2021. REUTERS/Dado Ruvic 

A coal miner sits before working in coal mine Abid Lolic in Nova Bila, Bosnia and Herzegovina May 12, 2021. Picture taken May 12, 2021. REUTERS/Dado Ruvic 

Coal miners prepare to work in coal mine Abid Lolic in Nova Bila, Bosnia and Herzegovina May 12, 2021. Picture taken May 12, 2021. REUTERS/Dado Ruvic 

Coal miners sit before working in coal mine Abid Lolic in Nova Bila, Bosnia and Herzegovina May 12, 2021. Picture taken May 12, 2021. REUTERS/Dado Ruvic 

Aerial view of Abid Lolic coal mine in Nova Bila, Bosnia and Herzegovina May 12, 2021. Picture taken May 12, 2021. Picture taken with drone. REUTERS/Dado Ruvic 

Aerial view of coal mine Abid Lolic in Nova Bila, Bosnia and Herzegovina May 12, 2021. Picture taken May 12, 2021. Picture taken with drone. REUTERS/Dado Ruvic 

A coal miner prepares to work in coal mine Abid Lolic in Nova Bila, Bosnia and Herzegovina May 12, 2021. Picture taken May 12, 2021. REUTERS/Dado Ruvic 

General view of Wujek Coal Mine is seen during sunset in Katowice, Poland October 16, 2108. Picture taken October 16, 2018. REUTERS/Kacper Pempel 

General view of Wujek Coal Mine is seen during sunset in Katowice, Poland October 16, 2108. Picture taken October 16, 2018. REUTERS/Kacper Pempel 

A section of coal is exposed in the rock face lining a road in Partridge, Kentucky, U.S., May 20, 2018. Picture taken May 20, 2018. REUTERS/Brian Snyder 

Steam rises from a pile of coal at a mine in Bishop, West Virginia, U.S., May 19, 2018. REUTERS/Brian Snyder 

A section of coal is exposed in the rock face lining a road in Partridge, Kentucky, U.S., May 20, 2018. REUTERS/Brian Snyder SEARCH "BLACK LUNG" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. 

Coal miners fill a cart inside an old artisanal coal mine, so called "Pique", in Curanilahue, Chile, May 7, 2018. Picture taken May 7, 2018. REUTERS/Jose Luis Saavedra 

A worker examines and prepares a Soviet-made rotary dredge with the productivity rate of 5,250 tons of processed coal a day during operations at the Beryozovsky opencast colliery, owned by the Siberian Coal Energy Company (SUEK), near the Siberian town of Sharypovo in Krasnoyarsk region, Russia, May 23, 2017. Picture taken May 23, 2017. REUTERS/Ilya Naymushin 

Typical miners houses are seen in front of a slag heap in Bruay-la-Buissiere, Northern France, April 6, 2017. Picture taken April 6, 2017. REUTERS/Vincent Kessler 

Piles of coal are placed at a yard in Shuangyashan, Heilongjiang province, China February 16, 2017. Picture taken February 16, 2017.REUTERS/Sue-Lin Wong 

Labourers working at a coal dump site warm themselves by a fire during a cold day on outskirts of Kabul, Afghanistan January 17, 2017. REUTERS/Mohammad Ismail 

Coal mining boots are shown above miners' lockers before the start of an afternoon shift at a coal mine near Gilbert, West Virginia May 22, 2014. REUTERS/Robert Galbraith/File Photo GLOBAL BUSINESS WEEK AHEAD PACKAGE - SEARCH 'BUSINESS WEEK AHEAD MAY 2' FOR ALL IMAGES 

A machine loads a BelAZ dump-body truck with coal at the Chernigovsky opencast colliery, outside the town of Beryozovsky, Kemerovo region, Siberia, Russia, April 4, 2016. The Chernigovsky opencast colliery is owned by the "SDS-Coal" company, third Russia's coal miner, which annually produces some 30 million tons of coal, according to company official representatives. Picture taken April 4, 2016. REUTERS/Ilya Naymushin 

A general view shows the Chernigovsky opencast colliery, outside the town of Beryozovsky, Kemerovo region, Siberia, Russia, April 4, 2016. The Chernigovsky opencast colliery is owned by the "SDS-Coal" company, third Russia's coal miner, which annually produces some 30 million tons of coal, according to company official representatives. Picture taken April 4, 2016. REUTERS/Ilya Naymushin 

A machine loads a BelAZ dump-body truck with coal at the Chernigovsky opencast colliery, outside the town of Beryozovsky, Kemerovo region, Siberia, Russia, April 4, 2016. The Chernigovsky opencast colliery is owned by the "SDS-Coal" company, third Russia's coal miner, which annually produces some 30 million tons of coal, according to company official representatives. Picture taken April 4, 2016. REUTERS/Ilya Naymushin 

A general view shows the Chernigovsky opencast colliery, outside the town of Beryozovsky, Kemerovo region, Siberia, Russia, April 4, 2016. The Chernigovsky opencast colliery is owned by the "SDS-Coal" company, third Russia's coal miner, which annually produces some 30 million tons of coal, according to company official representatives. Picture taken April 4, 2016. REUTERS/Ilya Naymushin 

Belarusian made BelAZ dump trucks and other vehicles are seen at the Chernigovsky opencast colliery, outside the town of Beryozovsky, Kemerovo region, Siberia, Russia, April 4, 2016. The Chernigovsky opencast colliery is owned by the "SDS-Coal" company, third Russia's coal miner, which annually produces some 30 million tons of coal, according to company official representatives. Picture taken April 4, 2016. REUTERS/Ilya Naymushin 

A machine loads a BelAZ dump-body truck with coal at the Chernigovsky opencast colliery, outside the town of Beryozovsky, Kemerovo region, Siberia, Russia, April 4, 2016. The Chernigovsky opencast colliery is owned by the "SDS-Coal" company, third Russia's coal miner, which annually produces some 30 million tons of coal, according to company official representatives. Picture taken April 4, 2016. REUTERS/Ilya Naymushin 

A loader fills railway cars with coal at the Chernigovsky opencast colliery, outside the town of Beryozovsky, Kemerovo region, Siberia, Russia, April 4, 2016. The Chernigovsky opencast colliery is owned by the "SDS-Coal" company, third Russia's coal miner, which annually produces some 30 million tons of coal, according to company official representatives. Picture taken April 4, 2016. REUTERS/Ilya Naymushin 

A driver gestures while driving a BelAZ dump-body truck loaded with coal coal at the Chernigovsky opencast colliery, outside the town of Beryozovsky, Kemerovo region, Siberia, Russia, April 4, 2016. The Chernigovsky opencast colliery is owned by the "SDS-Coal" company, third Russia's coal miner, which annually produces some 30 million tons of coal, according to company official representatives. Picture taken April 4, 2016. REUTERS/Ilya Naymushin FOR RPA ONLY 

BelAZ dump-body trucks transport coal at the Chernigovsky opencast colliery, outside the town of Beryozovsky, Kemerovo region, Siberia, Russia, April 4, 2016. The Chernigovsky opencast colliery is owned by the "SDS-Coal" company, third Russia's coal miner, which annually produces some 30 million tons of coal, according to company official representatives. Picture taken April 4, 2016. REUTERS/Ilya Naymushin 

A crew member operating a BelAZ 75710 truck works at a parking of the 'Chernigovets' coal company, outside the town of Beryozovsky, Kemerovo region, Siberia, Russia, April 4, 2016. Belarusian made world's largest pit dump-body truck Belaz 75710, with load-carrying capacity of 450 tons, was created in a single item and is now tested at the Chernigovsky opencast colliery owned by the 'SDS-Coal' company, according to company representatives. Picture taken April 4, 2016. REUTERS/Ilya Naymushin 

Employees operate a machine and a BelAZ dump-body truck at the Chernigovsky opencast colliery, outside the town of Beryozovsky, Kemerovo region, Siberia, Russia, April 4, 2016. The Chernigovsky opencast colliery is owned by the "SDS-Coal" company, third Russia's coal miner, which annually produces some 30 million tons of coal, according to company official representatives. Picture taken April 4, 2016. REUTERS/Ilya Naymushin 

Belarusian made BelAZ dump trucks and other vehicles are seen at the Chernigovsky opencast colliery, outside the town of Beryozovsky, Kemerovo region, Siberia, Russia, April 4, 2016. The Chernigovsky opencast colliery is owned by the "SDS-Coal" company, third Russia's coal miner, which annually produces some 30 million tons of coal, according to company official representatives. Picture taken April 4, 2016. REUTERS/Ilya Naymushin

A BelAZ dump-body truck transports coal at the Chernigovsky opencast colliery, outside the town of Beryozovsky, Kemerovo region, Siberia, Russia, April 4, 2016. The Chernigovsky opencast colliery is owned by the "SDS-Coal" company, third Russia's coal miner, which annually produces some 30 million tons of coal, according to company official representatives. Picture taken April 4, 2016. REUTERS/Ilya Naymushin

A machine loads a BelAZ dump-body truck with coal at the Chernigovsky opencast colliery, outside the town of Beryozovsky, Kemerovo region, Siberia, Russia, April 4, 2016. The Chernigovsky opencast colliery is owned by the "SDS-Coal" company, third Russia's coal miner, which annually produces some 30 million tons of coal, according to company official representatives. Picture taken April 4, 2016. REUTERS/Ilya Naymushin

Warehouses and the old part of the Ny-Alesund, Norway settlement from the coal mining period which closed in 1963, are seen October 11, 2015. A Norwegian chain of islands just 1,200 km (750 miles) from the North Pole is trying to promote new technologies, tourism and scientific research in a shift from high-polluting coal mining that has been a backbone of the remote economy for decades. Norway suspended most coal mining on the Svalbard archipelago last year because of the high costs, and is looking for alternative jobs for about 2,200 inhabitants on islands where polar bears roam. Part of the answer may be to boost science: in Ny-Alesund, the world's most northerly permanent non-military settlement, scientists from 11 nations including Norway, Germany, France, Britain, India and South Korea study issues such as climate change. The presence of Norway, a NATO member, also gives the alliance a strategic foothold in the far north, of increasing importance after neighbouring Russia annexed Ukraine's Crimea region in 2014. REUTERS/Anna FilipovaPICTURE 15 OF 19 - SEARCH "SVALBARD FILIPOVA" FOR ALL IMAGES
 

A Dendrobates leucomelas frog is pictured at a terrarium in Caracas November 30, 2015. Venezuelan frogs and toads are in critical danger due to climate change as rising temperatures complicate reproduction and spread a deadly fungus, say scientists, who liken the species to canaries in a coalmine warning of imminent danger. The survival of a group of nearly 20 frog and toad species, which top Venezuela's list of endangered species, may rest on a small group of academics in a Caracas laboratory attempting to recreate the amphibians' natural reproductive conditions. Picture taken on November 30, 2015. REUTERS/Carlos Garcia Rawlins 

Luis Merlo, a veterinarian, works in the Dendrobates leucomelas frogs habitat, at the terrarium facilities in Caracas November 30, 2015. Venezuelan frogs and toads are in critical danger due to climate change as rising temperatures complicate reproduction and spread a deadly fungus, say scientists, who liken the species to canaries in a coalmine warning of imminent danger. The survival of a group of nearly 20 frog and toad species, which top Venezuela's list of endangered species, may rest on a small group of academics in a Caracas laboratory attempting to recreate the amphibians' natural reproductive conditions. Picture taken on November 30, 2015. REUTERS/Carlos Garcia Rawlins 

Luis Merlo, a veterinarian, works in the frogs habitats at the terrarium facilities in Caracas November 30, 2015. Venezuelan frogs and toads are in critical danger due to climate change as rising temperatures complicate reproduction and spread a deadly fungus, say scientists, who liken the species to canaries in a coalmine warning of imminent danger. The survival of a group of nearly 20 frog and toad species, which top Venezuela's list of endangered species, may rest on a small group of academics in a Caracas laboratory attempting to recreate the amphibians' natural reproductive conditions. Picture taken on November 30, 2015. REUTERS/Carlos Garcia Rawlins 

Luis Merlo, a veterinarian, works in the frogs habitats at the terrarium facilities in Caracas November 30, 2015. Venezuelan frogs and toads are in critical danger due to climate change as rising temperatures complicate reproduction and spread a deadly fungus, say scientists, who liken the species to canaries in a coalmine warning of imminent danger. The survival of a group of nearly 20 frog and toad species, which top Venezuela's list of endangered species, may rest on a small group of academics in a Caracas laboratory attempting to recreate the amphibians' natural reproductive conditions. Picture taken on November 30, 2015. REUTERS/Carlos Garcia Rawlins 

Luis Merlo, a veterinarian, fills glass containers with food for Drosophila melanogaster larvae, that will be used as part of the diet for frogs, at the terrarium facilities in Caracas November 30, 2015. Venezuelan frogs and toads are in critical danger due to climate change as rising temperatures complicate reproduction and spread a deadly fungus, say scientists, who liken the species to canaries in a coalmine warning of imminent danger. The survival of a group of nearly 20 frog and toad species, which top Venezuela's list of endangered species, may rest on a small group of academics in a Caracas laboratory attempting to recreate the amphibians' natural reproductive conditions. Picture taken on November 30, 2015. REUTERS/Carlos Garcia Rawlins 

A Rhinella marina toad is pictured at a terrarium in Caracas November 30, 2015. Venezuelan frogs and toads are in critical danger due to climate change as rising temperatures complicate reproduction and spread a deadly fungus, say scientists, who liken the species to canaries in a coalmine warning of imminent danger. The survival of a group of nearly 20 frog and toad species, which top Venezuela's list of endangered species, may rest on a small group of academics in a Caracas laboratory attempting to recreate the amphibians' natural reproductive conditions. Picture taken on November 30, 2015. REUTERS/Carlos Garcia Rawlins 

Drosophila melanogaster larvae, that will be used as part of the diet for frogs, are seen inside glass containers at the terrarium facilities in Caracas November 30, 2015. Venezuelan frogs and toads are in critical danger due to climate change as rising temperatures complicate reproduction and spread a deadly fungus, say scientists, who liken the species to canaries in a coalmine warning of imminent danger. The survival of a group of nearly 20 frog and toad species, which top Venezuela's list of endangered species, may rest on a small group of academics in a Caracas laboratory attempting to recreate the amphibians' natural reproductive conditions. Picture taken on November 30, 2015. REUTERS/Carlos Garcia Rawlins 

A Mannophryne herminae frog is pictured at a terrarium in Caracas November 30, 2015. Venezuelan frogs and toads are in critical danger due to climate change as rising temperatures complicate reproduction and spread a deadly fungus, say scientists, who liken the species to canaries in a coalmine warning of imminent danger. The survival of a group of nearly 20 frog and toad species, which top Venezuela's list of endangered species, may rest on a small group of academics in a Caracas laboratory attempting to recreate the amphibians' natural reproductive conditions. Picture taken on November 30, 2015. REUTERS/Carlos Garcia Rawlins 

A Leptodactylus fuscus frog is pictured at a terrarium in Caracas November 30, 2015. Venezuelan frogs and toads are in critical danger due to climate change as rising temperatures complicate reproduction and spread a deadly fungus, say scientists, who liken the species to canaries in a coalmine warning of imminent danger. The survival of a group of nearly 20 frog and toad species, which top Venezuela's list of endangered species, may rest on a small group of academics in a Caracas laboratory attempting to recreate the amphibians' natural reproductive conditions. Picture taken on November 30, 2015. REUTERS/Carlos Garcia Rawlins 

A Ceratophrys calcarata frog is pictured at a terrarium in Caracas November 30, 2015. Venezuelan frogs and toads are in critical danger due to climate change as rising temperatures complicate reproduction and spread a deadly fungus, say scientists, who liken the species to canaries in a coalmine warning of imminent danger. The survival of a group of nearly 20 frog and toad species, which top Venezuela's list of endangered species, may rest on a small group of academics in a Caracas laboratory attempting to recreate the amphibians' natural reproductive conditions. Picture taken on November 30, 2015. REUTERS/Carlos Garcia Rawlins 

A Trachycephalus venulosus frog is pictured at a terrarium in Caracas November 30, 2015. Venezuelan frogs and toads are in critical danger due to climate change as rising temperatures complicate reproduction and spread a deadly fungus, say scientists, who liken the species to canaries in a coalmine warning of imminent danger. The survival of a group of nearly 20 frog and toad species, which top Venezuela's list of endangered species, may rest on a small group of academics in a Caracas laboratory attempting to recreate the amphibians' natural reproductive conditions. Picture taken on November 30, 2015. REUTERS/Carlos Garcia Rawlins 

A Hypsiboas crepitans frog is pictured at a terrarium in Caracas November 30, 2015. Venezuelan frogs and toads are in critical danger due to climate change as rising temperatures complicate reproduction and spread a deadly fungus, say scientists, who liken the species to canaries in a coalmine warning of imminent danger. The survival of a group of nearly 20 frog and toad species, which top Venezuela's list of endangered species, may rest on a small group of academics in a Caracas laboratory attempting to recreate the amphibians' natural reproductive conditions. Picture taken on November 30, 2015. REUTERS/Carlos Garcia Rawlins TPX IMAGES OF THE DAY

An Ameerega trivittatus frog is pictured at a terrarium in Caracas November 30, 2015. Venezuelan frogs and toads are in critical danger due to climate change as rising temperatures complicate reproduction and spread a deadly fungus, say scientists, who liken the species to canaries in a coalmine warning of imminent danger. The survival of a group of nearly 20 frog and toad species, which top Venezuela's list of endangered species, may rest on a small group of academics in a Caracas laboratory attempting to recreate the amphibians' natural reproductive conditions. Picture taken on November 30, 2015. REUTERS/Carlos Garcia Rawlins 

A miner walks at a coal mine from the state-owned Longmay Group on the outskirts of Jixi, in Heilongjiang province, China, October 24, 2015. To match story CHINA-COAL/JIXI Picture taken on October 24, 2015. REUTERS/Jason Lee 

Former miner Xin Qinling walks outside a closed exit of Zhengyang coal mine from the state-owned Longmay Group on the outskirts of Jixi, in Heilongjiang province, China, October 24, 2015. To match story CHINA-COAL/JIXI Picture taken on October 24, 2015. REUTERS/Jason Lee 

An abandoned excavator is partially covered by coal waste at a coal mine of the state-owned Longmay Group on the outskirts of Jixi, in Heilongjiang province, China, October 24, 2015. To match story CHINA-COAL/JIXI Picture taken on October 24, 2015. REUTERS/Jason Lee 

A general view shows Pinggang coal mine from the state-owned Longmay Group on the outskirts of Jixi, in Heilongjiang province, China, October 24, 2015. To match story CHINA-COAL/JIXI Picture taken on October 24, 2015. REUTERS/Jason Lee 

Wheels of cable rope are abandoned outside Zhangchen coal mine from the state-owned Longmay Group on the outskirts of Jixi, in Heilongjiang province, China, October 23, 2015. To match story CHINA-COAL/JIXI Picture taken on October 23, 2015. REUTERS/Jason Lee