An analysis of tens of thousands of scientific studies showed that climate change could already affect 85 percent of the world’s population.
The analysis, released on Monday, was conducted by a team of researchers who used machine learning to comb through huge treasure troves of research published between 1951 and 2018 and found around 100,000 papers that may have documented evidence of the effects of climate change on Earth’s systems.
“We have overwhelming evidence that climate change affects all continents and all systems,” said study author Max Callaghan of the AFP news agency in an interview.
He added that there is “a huge amount of evidence” showing how these effects are being felt.
The researchers taught a computer to identify climate-relevant studies and created a list of papers on topics from disrupted butterfly migration to heat-related deaths of humans to changes in forestry.
The studies rarely made a direct reference to global warming – Callaghan and teams from the Mercator Research Institute and Climate Analytics, both in Berlin, took on the task themselves.
Using location data from the studies, they divided the globe into a grid and mapped where documented climate impacts matched climate-related trends in temperature and precipitation.
For each grid cell, they asked: “Is it getting hotter or colder or wetter or drier outside the limits of natural variability?” Said Callaghan.
Then, he said, they checked whether this type of change was what climate models expected.
They found that 80 percent of the earth – home to 85 percent of the world’s population – had impact studies that were consistent with predictions of temperature and rainfall changes due to global warming.
It is crucial that the research has documented the climate impacts in richer countries disproportionately, with fewer studies in highly endangered regions.
For example, he said trends in temperature and rainfall in Africa could be linked to climate change.
“Developing countries are at the forefront of climate impacts, but we can see from our study that there are real blind spots when it comes to climate impact data,” contributing author Shruti Nath said, according to a Mercator press release.
âMost of the areas where we cannot tie the point mapping together are in Africa. This has real implications for adaptation planning and access to finance in these locations. “
Climate-related research has grown exponentially over the past few decades.
Between 1951 and 1990, “we have a total of about 1,500 studies,” said Callaghan, “while in the five years since the last” [UN] We have between 75,000 and 85,000 studies – a phenomenal increase. “
Callaghan said the sheer volume of research has made it impossible to individually identify all of the studies that reliably link the observed effects to man-made climate change.
Machine learning technology offers a global picture that could help experts synthesize large numbers of studies, Callaghan said, although he added that “it can never replace human analysis.”
“Our world map of climate impacts provides orientation for the global fight against global warming, for regional and local risk assessments and also for measures for climate adaptation on site,” he said according to the press release.
“Fossil fuels are killing us”
The World Health Organization and around three-quarters of the world’s health workers called on the governments at the world climate conference COP26 on Monday to step up climate protection measures, as they could save millions of lives every year.
The UN Health Authority’s report on climate change and health calls for transformative action in every sector, including energy, transport and finance, and says the public health benefits of ambitious climate action far outweigh the costs.
âBurning fossil fuels is killing us. Climate change is the greatest threat to human health, âthe WHO said on Monday.
The WHO previously said that around 13.7 million deaths each year, or around 24.3 percent of the global total, were caused by environmental risks such as air pollution and chemical exposure.
It’s not exactly clear how many of these are directly related to climate change, although WHO’s Maria Neira said about 80 percent of air pollution deaths could be prevented by following her guidelines.
The release of the report coincides with a letter endorsed by more than 400 health officials representing more than 45 million nurses, doctors and health professionals who are also calling for action.
“The measures called for in this letter – which are necessary but not sufficient to fully cope with the climate and health crisis – will make a major contribution to protecting people around the world,” says the letter.
Last week the United Nations Human Rights Council recognized access to a clean and healthy environment as a fundamental right, thereby strengthening its weight in the fight against climate change.