How climate change affects our health

Deadlier than COVID, or even rivalling cancer? Researchers have been increasingly attempting to calculate the effect climate change will have on health if the world does not act quickly to reduce carbon emissions.

The World Health Organization, which says climate change is the single biggest health threat facing humanity, has called for the issue to be "front and centre" in negotiations at the COP27 summit being held in Egypt.

But quantifying the overall impact is an extremely complicated task, experts told AFP, because global warming affects health in many different ways, from the immediate dangers of rising heat and extreme weather to longer-term food and water shortages, air pollution and disease.

The WHO estimates that climate change will cause 250,000 extra deaths a year from malnutrition, malaria, diarrhoea and heat stress between 2030 and 2050.That is widely thought to be a "massively conservative estimate" of the true toll, partly because it only comes from four sources. And Climate change is a threat multiplier.

As climate change worsens, we're going to see the biggest threats to human health increase.Nearly 70 percent of all deaths worldwide are from diseases that could be made worse by global warming, according to a report this year from the IPCC, the United Nations' panel of climate experts.

Another major health threat comes from food shortages. Nearly 100 million additional people faced severe food insecurity in 2020 compared to 1981-2010, according to a report last month from The Lancet Countdown, a leading effort to quantify climate change's impact on health.

Extreme drought has increased by nearly a third over the last 50 years, it added, putting hundreds of millions at risk of lacking access to fresh water.

And air pollution contributed to 3.3 million deaths in 2020, 1.2 million of which were directly related to fossil fuel emissions, the report found.

Researchers have also been sounding the alarm that warmer temperatures are pushing virus-carrying animals like mosquitoes into new areas, increasing the spread of existing diseases—and raising the risk of new ones jumping across to humans.

The likelihood of dengue transmission rose by 12 percent over the last 50 years, while warming temperatures extended malaria season in parts of Africa by 14 percent, The Lancet Countdown report said.

Projecting into the future, a new platform launched last week by the United Nations Development Programme and the Climate Impact Lab warned that global warming could become deadlier than cancer in some parts of the world.

Under the modelling research's worst-case scenario in which fossil fuel emissions are not rapidly scaled back, climate change could cause death rates to increase by 53 deaths per 100,000 people worldwide by 2100—around double the current rate for lung cancer.

For the current global population, that would mean 4.2 million additional deaths a year, more than the official toll from COVID-19 in 2021.

Climate change will influence every aspect of public health in the future.

Source:  AFP