Over 11,000 scientists from 153 countries signed a letter entitled “World Scientists’ Warning of a Climate Emergency,” which was published in the BioScience journal in November. Twenty-one of the signatories are faculty or graduate students at the University of Toronto.
The authors believe that public discourse on the climate crisis has been narrowly focused on global average surface temperature. They argue that this scope fails to fully capture how humans affect the planet, and communicate the dangers of the climate crisis.
Communicating the impact of the climate crisis
The authors note that a better solution for analysts would be to explore a wide range of indicators of the impact of human activity on the climate crisis.
They substantiated the letter with a series of graphs which illustrate the change of various indicators over the past 40 years, working with high-quality data collected by climate scientists.
Troubling trends that the graphs reveal include long-term increases in human and livestock populations, meat consumption, global loss of tree coverage, fossil fuel consumption, heightened airfare, and carbon dioxide emissions.
However, the authors note promising changes as well, such as decreases in global birth rates, the long-term slowdown of the rate of forest loss in the Amazon, rising infrastructure for solar and wind power, institutional fossil fuel divestment, and the prevalence of carbon pricing to reduce greenhouse gas emissions.
Yet the authors warn that these changes may not last — for example, fertility rates have been stabilizing, the rate of deforestation in the Amazon has risen once more, and while consumption of solar and wind energy has increased 373 per cent per decade, it was still 28 times smaller than fossil fuel consumption in 2018.
Despite 40 years of climate negotiations, the authors believe that business has continued as usual, and that the world at large is still failing to recognize the urgency of the climate crisis. They warn that we have failed to meaningfully change the ways we live, and that we are dangerously close to losing the ability to secure a sustainable future.
Six key areas where action can be taken
The authors outlined six key areas where action must be taken: energy, short-lived pollutants, nature, food, the economy, and population. They emphasized that fossil fuels must be replaced with low-carbon renewables and other clean energy sources, and that the emissions of short-lived pollutants such as methane and soot must be reduced.
They also stressed the importance of restoring Earth’s ecosystems. “Marine and terrestrial plants, animals, and microorganisms play significant roles in carbon and nutrient cycling and storage,” the authors noted.
Restoring ecosystems alone could bring the world to a third of the Paris Agreement’s emissions reduction target by 2030.
The authors also advise the elimination of animal consumption, especially ruminant animals like cattle and sheep; the curtailing of excessive extraction of Earth’s resources; and equitable solutions to population growth, such as family planning and widened access to girls’ education.
This is only a selection of the many recommendations in the “World Scientists’ Warning” — their breadth reflects the magnitude of the climate crisis. Fittingly, scientists from a wide variety of fields are represented among the signatories.
To learn more about the scientists’ perspectives, The Varsity reached out to four of U of T’s 21 signatories from a diverse range of academic disciplines.
How the climate crisis impacts public health
Dr. David Jenkins is a professor at U of T’s Faculty of Medicine who is well-known for developing the glycemic index — a system which explains how carbohydrates affect blood sugar levels.
Jenkins believes that it is important to connect the climate crisis to all the factors that it impacts, with health being one of them.
He also discussed the spread of diseases that are usually found in warmer climates to parts of the world that used to be colder due to the climate crisis.
Jenkins therefore believes that changing the impact of humans on the climate is of the utmost urgency. “The Intergovernmental Panel on Climate Change — two years ago — only gave us 12 years to turn the crisis around,” he said. “The world, in general, needs a wake-up call.”
This warning builds on all the other climate warnings that the world has received, Jenkins noted. The first was issued in 1798 by Reverend Thomas Malthus.
As a nutritionist, Jenkins believes that one way in which humans can reduce their impact on the climate crisis is by adopting plant-based diets — something which can also be incredibly healthy if planned well. For example, tofu and seitan are relatively inexpensive and healthy food sources.
However, he stressed that with plant-based diets, careful planning is important in order to meet nutritional requirements.
The urgency of addressing the crisis
The Varsity also reached out to Dr. Miriam Diamond, a professor at the Department of Earth Sciences who is cross-appointed to the Dalla Lana School of Public Health, the School of the Environment, and the Department of Chemical Engineering and Applied Chemistry.
Diamond highlighted that the climate crisis “is not just an issue… It is a crisis and needs to be treated as such.”
Natural phenomena such as the fires in Australia, the severe flooding in the Ottawa Valley, and the dramatic fires in western Canada and Ontario over the past two years all have a climate component, according to Diamond.
Diamond also brought up the recent federal election, noting that the climate crisis was not as high of a priority as affordability. “Our society is delicately positioned to function in [the] stable climate that we’ve known for the past several hundred years,” she said.
“[We do] not have the resources to cope with… the current and growing number of disasters,” she continued. “What’s coming further down are questions of food availability.”
“If we think we are worried about [it] right now… it’s about to get a whole lot worse.”
On activism and the paper’s research
Dr. Steve Easterbrook, Director of the School of the Environment, and a professor at the Department of Computer Science, hopes the letter will give the media and the public an overview of the current knowledge that we have about climate change.
“One of the things that paper does very nicely is it shows how everything is interconnected,” he noted.
In his view, the letter is also in defence of student climate activists, who are often dismissed in the media for their youth. “Articles like this, I think, emphasize that the students conducting this process, understand the science. They’ve got it right.”
He also underscored the value of dialogue about how to effectively fight the climate crisis. His belief is that scientists in disciplines not typically viewed as relevant to climate — including his own area of computer science — should consider how they could apply their skills to this issue.
“If you take this notion that we’re in a climate emergency,” he said, “I think of it as an ‘all-hands-on-deck’ type of emergency.”
Easterbrook rejected the notion that individuals reducing their personal carbon footprints is the most effective way to curb changes in climate. Instead, he urged people to consider: “What can you do that other people can’t do?”
A perspective from the Department of Political Science
Dr. Richard Sandbrook, a professor emeritus of the Department of Political Science, presented a different perspective. “The problem is not that we don’t know what to do; it is rather that we don’t do it,” he wrote.
One of the letter’s recommendations is for wealthy nations to aid poorer ones in the transition to renewables, which Sandbrook strongly supports.
He also wrote that the global south, whose nations are mostly not major contributors to warming, must be supported, or else “these areas will become unlivable, [and] internal wars and state breakdown will occur, along with major population movements.”
Unfortunately, Sandbrook believes that the political consequences of the climate crisis are not widely grasped. That is especially true of Canada, as it is far from Africa and the Middle East — regions which will feel the impacts of the climate crisis most strongly, according to Sandbrook, and where most climate migrations will originate.
Notably, while the graphs accompanying the letter include indicators of human activities that cause changes in climate, indicators of how these will affect humans — such as migration — are missing.
To Sandbrook, organization is critical. “The radical actions needed to arrest global heating at below 2°C will only happen in time as a result of mass pressure from below,” he noted.