Waterless Trevi Fountain is pictured as Italy lifts mandatory masks outdoors thanks to a decline in the coronavirus disease (COVID-19) cases and hospitalisations, in Rome, Italy, June 28, 2021. REUTERS/Guglielmo Mangiapane 

A person poses in front of waterless Trevi Fountain without wearing a mask as Italy lifts mandatory masks outdoors thanks to a decline in the coronavirus disease (COVID-19) cases and hospitalisations, in Rome, Italy, June 28, 2021. REUTERS/Guglielmo Mangiapane 

An aerial view shows a forest near Gummersbach, Germany, April 24, 2020, following an unusually warm, dry winter after a summer of record temperatures leaving forests dried out. REUTERS/Stephane Nitschke 

An aerial view shows a forest near Gummersbach, Germany, April 24, 2020, following an unusually warm, dry winter after a summer of record temperatures leaving forests dried out. Picture taken with a drone. REUTERS/Stephane Nitschke 

An aerial view shows a forest near Gummersbach, Germany, April 24, 2020, following an unusually warm, dry winter after a summer of record temperatures leaving forests dried out. Picture taken with a drone. REUTERS/Stephane Nitschke 

An aerial view shows a forest near Gummersbach, Germany, April 24, 2020, following an unusually warm, dry winter after a summer of record temperatures leaving forests dried out. Picture taken with a drone. REUTERS/Stephane Nitschke 

An aerial view shows a forest near Gummersbach, Germany, April 24, 2020, following an unusually warm, dry winter after a summer of record temperatures leaving forests dried out. Picture taken with a drone. REUTERS/Stephane Nitschke 

An aerial view shows a forest near Gummersbach, Germany, April 24, 2020, following an unusually warm, dry winter after a summer of record temperatures leaving forests dried out. Picture taken with a drone. REUTERS/Stephane Nitschke 

An aerial view shows a forest near Gummersbach, Germany, April 24, 2020, following an unusually warm, dry winter after a summer of record temperatures leaving forests dried out. Picture taken with a drone. REUTERS/Stephane Nitschke 

An aerial view shows a forest near Gummersbach, Germany, April 24, 2020, following an unusually warm, dry winter after a summer of record temperatures leaving forests dried out. Picture taken with a drone. REUTERS/Stephane Nitschke 

An aerial view shows a forest near Gummersbach, Germany, April 24, 2020, following an unusually warm, dry winter after a summer of record temperatures leaving forests dried out. Picture taken with a drone. REUTERS/Stephane Nitschke 

A woman walks past clothes kept for drying on railway tracks during a 21-day nationwide lockdown to slow the spreading of coronavirus disease (COVID-19) in in Mumbai, India, April 2, 2020. REUTERS/Prashant Waydande 

A cow stands on caked mud before a small patch of water at a dam as the region deals with a prolonged drought near Bulawayo, Zimbabwe, January 18, 2020. Picture taken January 18, 2020. REUTERS/Philimon Bulawayo 

Caked mud is seen before a small patch of water as the region deals with a prolonged drought at a dam near Bulawayo, Zimbabwe, January 18, 2020. Picture taken January 18, 2020. REUTERS/Philimon Bulawayo 

Soldiers patrol the Mormon community in La Mora, Sonora, Mexico January 10, 2020. Picture taken on January 10, 2020. REUTERS/Carlos Jasso 

Clouds gather but produce no rain as cracks are seen in the dried up municipal dam in drought-stricken Graaff-Reinet, South Africa, November 14, 2019. Picture taken November 14, 2019. REUTERS/Mike Hutchings TPX IMAGES OF THE DAY 

Clouds gather but produce no rain as cracks are seen in the dried up municipal dam in drought-stricken Graaff-Reinet, South Africa, November 14, 2019. Picture taken November 14, 2019. REUTERS/Mike Hutchings 

A dead lamb lies in the veld on a farm near drought-stricken Graaff-Reinet, South Africa, November 16, 2019. Picture taken November 16, 2019. REUTERS/Mike Hutchings TPX IMAGES OF THE DAY 

Cracks are seen in the dried up municipal dam in drought-stricken Graaff-Reinet, South Africa, November 14, 2019. Picture taken November 14, 2019. REUTERS/Mike Hutchings 

The skeleton of a dead goat lies in the veld on a farm near drought-stricken Graaff-Reinet, South Africa, November 16, 2019. Picture taken November 16 2019. REUTERS/Mike Hutchings 

A view shows dried cracked up soil on the edge of the Lake Wegnia, in Sahel region of Koulikoro, Mali November 23, 2019. Picture taken November 23, 2019. REUTERS/Arouna Sissoko 

Parched land is pictured around the Lake Wegnia, in Sahel region of Koulikoro, Mali November 22, 2019. Picture taken November 22, 2019. REUTERS/Arouna Sissoko 

The sun rises over dried up lake Pamamaroo, outside of Menindee, Australia, September 2, 2019. Prolonged drought exacerbated by demands on water resources by irrigators and cities means the Darling River (Barka) is running dry. The towns of Menindee and Wilcannia avoid drinking tap water, relying instead on charity donations of 10-litre boxes of water and rain tank water for potable uses. REUTERS/Tracey Nearmy SEARCH "NEARMY DROUGHT" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. 

Canals are pictured among burnt land after a forest fire near Banjarmasin in South Kalimantan province, Indonesia, September 29, 2019. REUTERS/Willy Kurniawan REFILE - CORRECTING NAME OF THE PROVINCE 

Burnt land is pictured next to a palm oil plantation after fires near Banjarmasin in South Kalimantan province, Indonesia, September 29, 2019. REUTERS/Willy Kurniawan REFILE - CORRECTING NAME OF THE PROVINCE 

A motorist rides a motorbike on a road through an area burnt due to the forest fires near Banjarmasin in South Kalimantan province, Indonesia, September 29, 2019. REUTERS/Willy Kurniawan REFILE - CORRECTING NAME OF THE PROVINCE 

Palm oil plantation is pictured next to a burnt forest near Banjarmasin in South Kalimantan province, Indonesia, September 29, 2019. REUTERS/Willy Kurniawan REFILE - CORRECTING NAME OF THE PROVINCE 

Capybaras are seen next to the road during prolonged drought conditions near San Rafael, Bolivia, September 27, 2019. REUTERS/David Mercado TPX IMAGES OF THE DAY 

Capybaras are seen next to the road during prolonged drought conditions near San Rafael, Bolivia, September 27, 2019. REUTERS/David Mercado 

Capybaras are seen next to the road during prolonged drought conditions near San Rafael, Bolivia, September 27, 2019. REUTERS/David Mercado 

A boat ramp leads to the drought-affected Split Rock Dam near Tamworth in rural Australia September 23, 2019. Picture taken September 23, 2019. REUTERS/Jonathan Barrett 

A water level indicator stands next to a near-empty creek near the town of Uralla in rural Australia September 24, 2019. Picture taken September 24, 2019. REUTERS/Jonathan Barrett 

Cattle are seen near San Ignacio de Velasco, Bolivia, September 25, 2019. Picture taken September 25, 2019. REUTERS/David Mercado 

Cattle are seen near San Ignacio de Velasco, Bolivia, September 25, 2019. Picture taken September 25, 2019. REUTERS/David Mercado 

Cattle are seen near San Ignacio de Velasco, Bolivia, September 25, 2019. Picture taken September 25, 2019. REUTERS/David Mercado 

Cattle are seen near San Ignacio de Velasco, Bolivia, September 25, 2019. Picture taken September 25, 2019. REUTERS/David Mercado 

Cattle are seen in Santa Teresita, Charagua, Bolivia, September 24, 2019. REUTERS/David Mercado 

A cow is seen in Santa Teresita, Charagua, Bolivia, September 24, 2019. REUTERS/David Mercado 

Cattle are seen in Santa Teresita, Charagua, Bolivia, September 24, 2019. REUTERS/David Mercado 

A capybara is seen in Santa Teresita, Charagua, Bolivia, September 24, 2019. REUTERS/David Mercado 

A plant is seen in a burned forest at the Nembi Guasu conservation area in the Charagua, Bolivia, September 24, 2019. REUTERS/David Mercado 

Charred trees are pictured near Robore, Bolivia, September 24, 2019. REUTERS/Edgard Garrido 

A view shows a burned forest at the Nembi Guasu conservation area in the Charagua, Bolivia, September 24, 2019. REUTERS/David Mercado 

Trees charred are pictured near Robore, Bolivia, September 23, 2019. REUTERS/Edgard Garrido 

A dried-out part of Lake Koronia, Greece, September 19, 2019. Picture taken September 19, 2019. REUTERS/Alexandros Avramidis 

A dried-out part of Lake Koronia, Greece, September 19, 2019. Picture taken September 19, 2019. REUTERS/Alexandros Avramidis 

An aerial view shows a deforested plot of the Amazon near Porto Velho, Rondonia State, Brazil, September 17, 2019. REUTERS/Bruno Kelly 

An aerial view shows a deforested plot of the Amazon near Porto Velho, Rondonia State, Brazil, September 17, 2019. REUTERS/Bruno Kelly 

An aerial view shows a deforested plot of the Amazon near Porto Velho, Rondonia State, Brazil, September 17, 2019. REUTERS/Bruno Kelly TPX IMAGES OF THE DAY 

An aerial view shows a deforested plot of the Amazon near Porto Velho, Rondonia State, Brazil, September 17, 2019. REUTERS/Bruno Kelly 

Dried mud is seen during a low-level period of water in Concepcion reservoir on the outskirt of Tegucigalpa, Honduras September 14, 2019. REUTERS/Jorge Cabrera 

Dried mud is seen during a low-level period of water in Concepcion reservoir on the outskirt of Tegucigalpa, Honduras September 14, 2019. REUTERS/Jorge Cabrera 

Dried mud is seen during a low-level period of water in Concepcion reservoir on the outskirt of Tegucigalpa, Honduras September 14, 2019. REUTERS/Jorge Cabrera 

Dried mud is seen during a low-level period of water in Concepcion reservoir on the outskirt of Tegucigalpa, Honduras September 14, 2019. REUTERS/Jorge Cabrera 

A deforested and burnt area is seen in an indigenous area used as a cattle pasture in Areoes, Mato Grosso state, Brazil, September 4, 2019. Picture taken September 4, 2019. REUTERS/Lucas Landau 

A sign that reads "2000 pesos fine for rubbish dumping" stands in Desaguadero village, Lago Menor, Bolivia, July 12, 2018. REUTERS/Manuel Seoane SEARCH "TITICACA CLIMATE" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. 

A dry pond is pictured in a village of Menhai county in Xishuangbanna Dai Autonomous Prefecture, Yunnan Province, China, July 12, 2019. Picture taken July 12, 2019. REUTERS/Aly Song 

A dead fish is seen in a dry pond in a village of Menhai county in Xishuangbanna Dai Autonomous Prefecture, Yunnan Province, China, July 12, 2019. Picture taken July 12, 2019. REUTERS/Aly Song 

A dead fish lies on the bank of Mekong River in Nakhon Phanom, Thailand July 24, 2019. Picture July 24, 2019. REUTERS/Soe Zeya Tun 

A view of Monument Valley in Utah, US, June 27, 2019. Picture taken June 27, 2019. REUTERS/Pamela J. Peters