Renegade US to owe lives to India, China
New Delhi: Cuts in greenhouse gas emissions by China and India among other countries will help save lives in America even if the US, steered by President Donald Trump, withdraws from the Paris climate accord, scientists said on Tuesday.
Global reductions in greenhouse gas emissions will avert 24,000 premature deaths from air pollution in the US, with 31 per cent of the avoided deaths resulting from emission cuts in foreign countries, the scientists have found.
Their study, published on Tuesday in the journal Environmental Research Letters, has been described as the first to quantify how reductions in greenhouse gas emissions by other countries can affect air quality and health in the US.
The findings come at a time US President Donald Trump has decided to pull his country out of the Paris accord of 2015, which seeks global emission cuts to minimise climate change.
"Most actions that reduce greenhouse gas emissions also reduce emissions of air pollutants, particularly from fossil fuel sources," Jason West, associate professor in the department of environmental science and engineering at the University of North Carolina, who led the study, told The Telegraph.
West and his colleagues used computer simulations to determine the effect of global emission reductions on two types of air pollutants: tiny inhalable particulate matter (PM) and ozone.
Past studies had shown that PM and ozone can exacerbate asthma and respiratory distress, and increase the risk of premature mortality from cardiovascular diseases, respiratory disorders and cancer.
Particulate matter and ozone have long enough life spans in the atmosphere to move across continents and influence human health in areas far beyond their source locations.
The study by West and his colleagues suggests that global cuts in greenhouse gas emissions will reduce premature deaths linked to PM exposure by 16,000 and those linked to ozone by 8,000 by 2050.
"We separated the overall health benefits in the US into contributions from domestic greenhouse gas reductions versus foreign greenhouse gas reductions, and found that foreign reductions had an important influence," West said.
"The US can gain significantly greater benefits for air quality and human health, especially for ozone, by working together with other countries to combat global change," said Yuqiang Zhang, environmental scientist at the UNC and lead author of the study.
China, the world's largest emitter of greenhouse gases, and India, the fourth-largest after the US and the European Union, are expected to contribute to global reductions in emissions.
In an earlier study, West and his colleagues had shown that global emission cuts would slow climate change and improve air quality worldwide to avert about 500,000 premature deaths from air pollution in the year 2030.