KATHMANDU: Nepal's snow-capped mountains have lost close to one-third of their ice in over 30 years due to global warming, U.N. Secretary-General Antonio Guterres said on Monday after a visit to the area near Mount Everest, the world's highest peak.

Climate scientists say the earth's temperature has increased by an average of 0.74 degrees Celsius over the past 100 years, but warming across South Asia's Himalayas has been greater than the global averages.

Glaciers in Nepal, wedged between two major carbon polluters - India and China, melted 65% faster in the last decade than in the previous one, the U.N. chief said in a video message after visiting the Solukhumbu region.

"I am here today to cry out from the rooftop of the world: stop the madness," he said, calling for an end to "fossil fuel age" with the warning that melting glaciers would mean swollen lakes and rivers sweeping away entire communities, and seas rising at record rates.

Glaciers in the Hindu-Kush Himalaya could lose up to 75% of their volume by century's end due to global warming, scientists said in a report published in June this year, causing dangerous flooding and water shortages for 240 million people who live in the mountainous region.

Climbers returning from Everest have said the mountain was dryer and greyer now.

"Record temperatures mean record glacier melt. Nepal has lost close to one-third of its ice in just over 30 years," Guterres, who is on a four-day visit to the country, said.

He also urged countries to limit global temperature rise to 1.5 degrees Celsius to avert "the worst of climate chaos".