OSLO • Climate change has caused severe harm to human health since the year 2000 by stoking more heat waves, the spread of some mosquito-borne diseases and under-nutrition as crops fail.
Scant action to slow global warming over the past 25 years has jeopardised "human life and livelihoods", scientists wrote in a report published in The Lancet, a British medical journal, yesterday.
"The human symptoms of climate change are unequivocal and potentially irreversible," said the report, titled Lancet Countdown and drawn up by 24 groups, including the World Bank and the World Health Organisation (WHO).
Many governments are trying to cut their greenhouse gas emissions under the 2015 Paris climate agreement, though President Donald Trump has weakened the pact by saying the US, the world's second biggest greenhouse gas polluter after China, will pull out.
The findings show an additional 125 million vulnerable people had been exposed to heat waves each year from 2000 to 2016, with the elderly especially at risk. Labour productivity among farm workers fell by 5.3 per cent since the year 2000, mainly because sweltering conditions sapped the strength of workers in nations from India to Brazil.
The report, based on 40 indicators of climate and health, said climate change seemed to be making it easier for mosquitoes to spread dengue fever, which infects up to 100 million people a year.
The number of undernourished people in 30 countries across Asia and Africa rose to 422 million in 2016 from 398 million in 1990, the report said, adding: "Undernutrition is identified as the largest health impact of climate change in the 21st century."
The number of weather-related disasters such as hurricanes and floods rose 46 per cent since 2000, but the number of deaths remained stable, suggesting better protection against environmental crises.
The Lancet study also said the air in 87 per cent of all cities, home to billions of people, exceeded pollution guidelines set by the WHO. Fossil fuels release both toxins and heat-trapping carbon dioxide when burnt.
Almost 200 nations will meet in Germany from Nov 6 to 17 to work on a "rule book" for the 2015 Paris climate agreement for shifting from fossil fuels.