Climate change is affecting every continent across the globe. Climate research, on the other hand, is in need of catching up.
There are far more studies on climate impacts in high-income countries than in low-income countries, according to a new study that reviewed more than 100,000 published climate research papers.
It’s a problem the authors refer to as an “attribution gap” — an imbalance in the scientific evidence for the influence of global warming in different regions.
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"These are blind spots we will need to fill in if we want to respond to climate change in an informed way, and if we want to truly comprehensively assess the evidence of climate impacts," said Max Callaghan, a researcher at the Mercator Research Institute on Global Commons and Climate Change in Germany, in an email.
Callaghan led the study alongside a team of researchers from Mercator, nonprofit research group Climate Analytics and other research institutes in Europe and the U.S.
The study, published yesterday in the journal Nature Climate Change, used machine learning — a form of artificial intelligence — to sift through scientific databases and pick out studies on the impacts, or consequences, of climate change around the world. That’s everything from fires, floods and other disasters to the effects of warming on specific plants, animals and human societies across the globe.
The scientists screened out research focused solely on potential future effects of climate change, and kept only studies that include the impacts of warming already observed on the Earth. In all, they ended up with around 102,000 relevant studies.
The researchers then mapped out the geography of all the research. First they divided the globe into a giant grid. Then they used their machine learning system to identify the geographic focus of each study, noting how many studies landed within each grid cell across the map.
The scientists then went back and compared their map with an analysis of the places on Earth where climate scientists have already concluded — typically with the help of models — that temperatures or rainfall patterns are changing, and that human-caused climate change is to blame.
The researchers refer to this as a “two-step” attribution process, identifying the places on Earth where the climate is changing and where scientists are studying its consequences.
Their biggest, and perhaps least surprising, finding: Climate impacts are already apparent across almost the entire globe. The studies identified by the researchers spanned about 80 percent of the world’s land area, home to about 85 percent of the world’s human population.
That doesn’t necessarily mean the other 20 percent of the world’s land mass isn’t seeing the impacts of climate change. It simply means the machine learning system didn’t find any studies focused on those areas.
The researchers then looked a little closer to find out which parts of the world had the strongest evidence for the impacts of climate change.
They found that about 48 percent of the world’s land area had “robust or high levels of evidence” for climate impacts. (The scientists defined “robust levels” as having at least five climate impact studies per grid box on the map.)
On the other hand, at least a third of the world’s land area had comparatively little evidence for climate impacts. Many of these areas are places where scientists know temperatures and rainfall patterns are changing because of climate change — there just haven’t been many studies on exactly how those changes are affecting human societies and natural ecosystems.
It’s not that climate change isn’t affecting these places, the researchers note. It just hasn’t been well studied there.
There are clear divisions across geographic and economic lines, the study finds. High-income countries are nearly twice as likely to have high evidence for climate impacts — that is, at least five studies per grid cell — as low-income countries. Low evidence, defined by fewer studies per grid cell, is especially prevalent across Africa and Asia.
That means large swaths of the Earth’s population live in places where there’s been relatively little research on the consequences of climate change. Nearly a quarter of the population of low-income countries resides in places with low evidence for climate impacts, compared with just 3 percent of the population in high-income countries.
There are likely multiple challenges contributing to the discrepancies, Callaghan noted. There's often a major imbalance in the scientific resources available in high-income countries versus low-income countries. The ability to pay processing fees, often required to submit studies to certain scientific journals, can also be a barrier.
Solving these problems will require a shift in scientific priorities and research funding alike.
Callaghan added that "this won't be simply about getting researchers from the Global North to study areas in the Global South." Partnerships and collaboration with researchers from understudied regions are key to filling in the gaps.
The study highlights yet another inequality associated with climate change around the world.
Many studies have found that climate change disproportionately affects certain vulnerable groups, particularly lower-income communities and people of color. These groups are often more likely to reside in places where factors like environmental pollution, fewer green spaces and less reliable access to health care can worsen the impacts of extreme heat and other natural disasters.
At the same time, many regions around the world that have emitted the lowest cumulative levels of greenhouse gases — in other words, the places least responsible for climate change — are being strongly affected by the consequences of global warming.
Now, the new study points out that many of these places are also less studied than their wealthier counterparts.
It's not the first study to highlight the problem, Callaghan noted. Scientists have flagged the issue before. He pointed to a 2015 study in Global Change Biology that also concluded that many regions in the subtropics and tropics are understudied compared with other parts of the world.
That means the full picture of climate change around the world is still incomplete, even as its impacts are growing steadily more severe. And the Earth’s most vulnerable places remain its least understood.
Reprinted from E&E News with permission from POLITICO, LLC. Copyright 2021. E&E News provides essential news for energy and environment professionals.