Author's Note
I am an EA and student at the American University of Sharjah. This is a paper on climate change and X-risk that I wrote for a writing course. I'm new to EA and would appreciate any feedback.
Abstract
Climate change is one of the most popular global concerns today. However, according to the principles of Effective Altruism, a philosophical and social movement that applies reason and evidence to philanthropy, climate change should not be our top global priority. To support my position, I claim that climate change will not make the entire Earth uninhabitable, it will not benefit from more attention, and that other issues pose a greater risk to humanity. Critics of my position argue that climate change should not be deprioritised because it has serious effects, that humanity has less than a decade left due to climate change, and that it can cause a socioeconomic collapse leading to extinction. Considering our limited resources and how prominent concerns about climate change have become, we need to thoroughly examine the threat climate change poses to enable us to manage it effectively.
Keywords: climate change, global warming, Effective Altruism, global priorities research, existential risk
The Threat of Climate Change Is Exaggerated
I was born in 2002 and my generation grew up with constant reminders of the dangers of climate change. From a young age, I participated in mass recycling drives and reforestation efforts. By the end of high school, I had become intensely passionate about climate change. I was convinced that climate change was our most pressing issue, yet nobody seemed to care. It was baffling to me how governments made so little effort to right humanity’s wrongs even when our end seemed so near. Then, two years into university, I discovered a philosophical and social movement called Effective Altruism (EA). EA forced me to re-evaluate how I approached philanthropy and what I believed about global problems. I was shocked to discover that climate change was not as pressing a problem as I previously thought, and that it is unlikely to end humanity. It took tremendous amounts of evidence to challenge my strongly held beliefs, and I will present the same evidence as I argue in this paper that climate change should not be a priority.
I will focus on three main arguments to support my claim. First, I explore how climate change will not make the entire Earth uninhabitable, but only small pockets of it. Former climate physicist and effective altruist Neil Bowerman explains how habitability is determined by our social and technological capabilities, and even at current rates of global warming, some habitable areas will remain (Centre for Effective Altruism, 2019). Second, I argue that climate change is a much less neglected area as compared to other global problems. EA reports on climate change conclude that current spending in the area is more than is effective (Duda & Koehler, 2016). Finally, I show that other causes pose a greater risk to humanity. Indeed, Ord (2020) suggests that engineered pandemics and unaligned artificial intelligence (AI), a term referring to AI that deviates from human guidance, should be our biggest concerns today.
I also consider several potential counterarguments to my claim. Some argue that there is enough evidence of the serious effects of climate change to challenge EA’s position regarding the relative importance of the area. Others claim that humanity has less than a decade left due to climate change. I will show how this is a misunderstanding of a popular report from the Intergovernmental Panel on Climate Change (IPCC) and use the report to refute the previous claim. Still others have demonstrated that climate change can cause socioeconomic collapse, which in turn can lead to extinction. This is a particularly interesting claim and one that I agree with. However, it only warrants an increased focus on solving socioeconomic weaknesses, not prioritizing climate change.
Climate change is one of the most publicized global problems. Most people believe it to be a higher risk than it really is. Furthermore, current efforts in the field are more than is necessary, and are even futile. A close examination of the real threats of climate change is necessary to ensure that we do not waste precious resources where they are not immediately required. Moreover, biosecurity risks and unaligned AI pose a much larger threat to our existence, but do not receive enough attention. That being said, it is important to stress at the outset that while climate change should be assigned a lower priority, we should not abandon the cause altogether. As the findings in this paper show, resources can and should be reallocated both within the field of climate change and towards other pressing problems.
A Crash Course in Effective Altruism
In the opening chapter of Doing Good Better, William MacAskill (2015) describes how Kremer and Glennerster discovered that the best way to improve school attendance and performance in Kenyan schools was by treating children for intestinal worms, rather than by providing or improving educational resources. They arrived at this surprising conclusion by applying the principles of controlled trials from the medical world to philanthropy. To most of us, mixing reason and charity seems counterintuitive, cold-hearted even. Yet, this approach not only helps us use our time and resources effectively, but also prevents us from accidentally causing harm. Effective Altruism is a movement that embodies this idea of introducing reason and evidence to help us do the most good we can (“Introduction to Effective Altruism”, 2020).
Kremer and Glennerster provided Kenyan children with additional books, flipcharts, and teachers before beginning deworming initiatives. They quickly discovered that deworming is far more effective than the other approaches, increasing attendance by 25% and future income by 20% (MacAskill, 2015). With every global problem, we see the same pattern; the approach that works best does far better than other approaches. Applying the same evidence-based reasoning to global problems, it becomes clear that some areas have more serious impacts than others. Moreover, certain causes benefit far more from extra resources. Does $100 do more good if spent on scientific research or on economic reform? Global priorities research is a field that aims to answer such questions (Duda, 2016).
Our resources, both tangible and intangible, are limited. Global priorities research applies principles from economics, mathematics, statistics, and the social sciences to help organizations decide which global causes need their resources. EA assesses causes across three parameters to arrive at a list of priorities: scale, neglectedness, and tractability. Scale, or importance, measures how many lives the problem affects. Neglectedness is a measure of how many people are currently addressing the issue. Tractability, or solvability, evaluates how easily the problem can be solved (“Introduction to EA”, 2020).
One such global priority area is existential threats, which refers to causes that pose a risk to humanity’s existence. EA is partly driven by the idea that the long-term consequences of our actions should be taken into consideration. Human extinction is an easily preventable long-term issue, so it makes sense to focus on this area. Global priorities research evaluates the existential threat that different global problems pose. Their research into climate change concludes that by itself, it is not a threat to human existence (Duda & Koehler, 2016).
Climate Change: The Road to Fame
A 2011 survey in the United States found that public perception of climate change depends heavily on local climate change (Rabe & Borick, 2012). Due to our empirical nature of reasoning, humans are inclined to accept as fact what we experience firsthand. In the last fifty years, local climate fluctuations have become more commonplace, leading to a shift in public perception. Today, climate awareness is ubiquitous and unavoidable. But have we perhaps taken it too far? In the following sections, I will examine the key reasons that made climate change such a popular concern and evaluate their validity.
Do We Really Only Have a Decade Left?
In 2015, the Intergovernmental Panel on Climate Change (IPCC) published a report that would guide the global climate response for years to come (IPCC, 2015). Soon after, individuals and organizations concerned with climate action began to panic about one of the warnings listed in the report—that we have until 2030 to reverse climate change. Media outlets responded with a staggering number of articles claiming that we have a decade left until we can no longer fix the damage we have done. Understandably, the world was afraid. Climate activists began to push harder for action and reform. One might wonder whether this alarmed response was justified.
In reality, the 2015 IPCC report states that “delaying additional mitigation to 2030 will substantially increase the challenges associated with limiting warming” (p. 40). Clearly, the panic elicited by the report was misplaced and can be credited to a gross misunderstanding of the report. It is not that climate change cannot be fixed after 2030, merely that it will be harder to fix. It is important to note that even this implication is grave; fixing climate change after 2030 will take up far more resources. However, correcting this misunderstanding causes a major shift in the way we view the current effects of climate change, and consequently affects our evaluation of its threats.
Evidence of the Effects of Climate Change
Undeniably, climate change has caused much damage to natural and human systems across the globe. The 2015 IPCC report, with a vague but reasonably high confidence (IPCC, 2010), states that impacts such as changing precipitation patterns, shifting biospheres, and decreased crop yields can be attributed to climate change. These effects feel more tangible where they are visible; people living in areas prone to natural disasters are more likely to be climate activists. Most climate activists and some fellow effective altruists are outraged at how climate change is deprioritised by the EA in spite of strong evidence of its effects on natural and human systems (Robertson, 2020).
There are, however, two important points to note. Firstly, the observed effects of climate change are serious, but not grave enough to pose a threat to human existence. In fact, most of these problems can be managed by properly reallocating resources within climate change towards specific solutions, such as research in biotechnology for improved crop yields (Conrow, 2018). Secondly, as dreadful as the consequences of climate change are, they constitute only a small portion of risks to humanity. For example, compared to other causes, the contribution of climate change to human illnesses is quite small (IPCC, 2015). Therefore, although climate change is a serious issue, it should be less of a priority.
A Potential Domino Effect
Climate change can cause a wide range of changes across the world. One such change is the shifting of the tropics due to global warming. This shift will consequently relocate farming regions away from the equator. Countries that currently supply most of our food will cease to do so and new countries will take over this role. This shift will dismantle existing food supply chains. In the long-term, such changes will lead to political instability, even societal collapse. In 2021, Richards et al. found empirical evidence to support this forecast. Many claim that the potential of this societal collapse to lead to extinction is a reason to focus on climate change.
These claims and concerns are rational. Even key individuals within EA, like Neil Bowerman, agree with the potential of climate change to cause a domino effect leading to societal collapse (Centre for Effective Altruism, 2019). However, this does not suggest that concerns of extinction by societal collapse warrant increased focus on climate change. Rather, it should inspire us to work on preventing societal collapse from disrupted food supply chains. This can be achieved by working on the prevention of power conflicts or by promoting better global governance, two of the highest priority areas listed by the EA (“Our current list”, 2016). After all, turning off the water supply is not the most effective way to fix a leaking tap.
Why Climate Change Should Not Be a Priority
On April 6, 2022, eleven climate scientists across the United States were arrested for rioting to demand stronger climate action. By the end of the week, 1,000 scientists around the world had joined them in protests (Starke, 2022). In a world where such demonstrations have become commonplace, it would not be unreasonable to conclude that climate change is a high priority cause. In fact, to convince anyone otherwise would take tremendous amounts of evidence. In the following paragraphs, I take on the seemingly impossible task of demonstrating that while scientists are right to demand better climate action, climate change is not our highest priority.
Earth Will Not Become Uninhabitable
Rising sea levels and increasing temperatures have made headlines in the past few years, leading the public to believe that the Earth will soon become uninhabitable. Neil Bowerman, a former climate scientist, explains that social and technological factors determine Earth’s habitability. As a species, we have made considerable technological progress. If the current trends of progress continue, only pockets of Earth will become completely uninhabitable for humans (Centre for Effective Altruism, 2019). This may create more climate refugees, but will not cause death. This forecast receives higher confidence when our high adaptability as a species is taken into consideration. Bowerman also concedes that climate change is causing several thousand premature deaths (Centre for Effective Altruism, 2019). However, this number is not large enough to cause human extinction.
A wide range of climate models suggest that by 2100, global temperatures will rise from 1 to 5 degrees Celsius (Herring, 2012). To those of us without a background in climate science, these numbers give no information on what this means for humanity. To put it into perspective, we must consider our adaptability. Sherwood and Huber (2010) evaluate this by considering the past and the future. During the Paleogene era, global temperatures were 10 degrees Celsius higher than they are today, yet mammals survived. They then analyze data across several periods to determine how much further of an increase in global temperatures we can survive. They conclude that temperatures can rise to 11 degrees Celsius before the share of uninhabitable areas begins to include most of today’s population. Even at 10 degrees Celsius, the damage is equivalent only to a recession that would set us back by 20 years. However, this still does not imply extinction. Although Sherwood and Huber (2010) raise concerns that unmitigated climate change can cause more than 11 degrees of increase in temperature, Herring’s predictions of projected global temperatures shows that such an increase is unlikely. Therefore, Earth will not become uninhabitable in the near future.
We must, however, consider that climate change has begun to cause premature deaths. For example, Robine et al. (2008) observe that the European heatwave of 2003 alone caused over 70,000 deaths. This number too needs perspective. According to Roser et al. (2016), in the years since the Second World War, a little under 100,000 people die annually from war and conflict. This is not an existential threat to a population of seven billion. Therefore, climate change, which causes fewer deaths, is not an existential threat either. To reiterate, although climate change will cause deaths and displacements, it is not an extinction-level threat.
Climate Change Is Not Neglected
Waking up every morning to new reports of burning forests and melting glaciers is terrifying. Any logical person would wonder why it does not receive more attention. It seems counterintuitive to turn away from a problem everyone talks about. But that is precisely why climate change will not benefit from more attention. Effective Altruism defines neglectedness, one of the criteria used to prioritize cause areas, as a percentage increase in resources per extra person or dollar (Wiblin, 2016). In other words, neglectedness is a measure of how much marginal impact a single person will have. According to the law of diminishing marginal returns, adding a production factor decreases the output per unit (Hayes, 2022). By this logic, an area such as climate change that receives so much attention already will not benefit from receiving more.
In 2017 and 2018, the world invested an annual average of $579 billion dollars on climate change. This marks a 25% increase from 2015 and 2016 (Buchner, 2019). In the same period, greenhouse gas emissions have increased from 46.76 to 48.94 billion tonnes (Ritchie, 2020). The increase in spending from 2016 to 2017 did not correspond to any decline in emission rates. Clearly, the optimum amount to spend on mitigating climate change is less than what is currently being allocated. Indeed, EA organizations conclude from their analyses that the appropriate annual amount is in the range from $10 billion to $100 billion dollars (Duda & Koehler, 2016).
If we apply the law of diminishing returns to climate change, it is clear that this area is not neglected. Allocating more time, money, or other resources towards this area is therefore unwise and will not cause much more impact. Why then is five times the optimal spending not causing any significant changes in emissions? After all, climate change receives a lot more attention than problems that pose a higher existential risk. Experts within the EA community suggest that the resources within climate change are poorly allocated, resulting in little to no actual improvements where needed (Duda & Koehler, 2016). Moving forward, our objective should not be to increase the resources spent on this area, but to reallocate what is already being spent.
There Are Larger Threats
Toby Ord’s The Precipice (2020) details the many risks threatening the long-term existence of humanity. Ord begins by dividing potential risks into two categories: natural and anthropogenic. Extinction from natural causes, like asteroid impact, supervolcanic eruption, or stellar explosion, has a combined risk of only 0.05 percent. Anthropogenic risks, which are caused by humans, are far more dangerous. The first of these discussed in the book is nuclear war. In fact, Ord describes the detonation of the first atomic bomb as the event that propelled humanity onto “the precipice”—the precarious age we now live in where technology has given us the ability to destroy ourselves. Ord then goes on to evaluate the risks that climate change, engineered pandemics, and unaligned artificial intelligence (AI) pose.
Engineered pandemics have about a 1 in 30 chance of posing an existential risk in the next 100 years, while unaligned AI has a 1 in 10 chance. In comparison, climate change has only a 1 in 1000 chance of causing an existential crisis (Ord, 2020). In fact, the fallout from engineered pandemics or unaligned AI could be much graver than that from climate change and will arrive much faster if left unchecked. The threat of engineered pandemics looms much larger in the wake of the COVID-19 pandemic. Factoring in the power biotechnological advancements have to enhance the capabilities of bio risks, this particular existential threat becomes more menacing. At the same time, there is much we do not yet know about AI, a relatively new field. Even with our current knowledge, however, it is clear that unaligned AI poses the highest risk to our existence (Ord, 2020), signalling grave predictions about what is yet to be discovered.
Although engineered pandemics and unaligned AI pose a much larger threat to human existence, neither area receives much attention. Both of these causes receive a small percentage of what is being spent on climate research and action. Research into shaping the development of AI positively only receives around $100 million dollars a year (Wiblin, 2017). Biosecurity risks are faring slightly better with an estimated $1 billion dollars spent annually (Lewis, 2020). Spending in both areas is not anywhere near what is needed to avert the impending crises. Considering that these areas pose a greater risk to humanity, it would be wise for the world to shift its focus from climate change to these larger threats.
Conclusion
Climate change has long enjoyed a misplaced status of a high priority concern in communities and organizations. As explored in this paper, this popularity was largely due to misunderstandings of the 2015 IPCC report. The poorly stated findings of this report led to the widely held belief that humanity has roughly a decade left to fix climate change. However, the report actually details the effects climate change has had and is projected to have on natural and human systems and shows that these effects are very troubling but not extreme. Despite the prevalence of climate change awareness, few are aware of its potential to cause societal collapse, which can lead to extinction. However, this is not an argument to prioritize climate change. Rather, as argued in this paper, it is a reason to focus on research into global cooperation.
To prove that climate change should not be our priority, I demonstrated that it will not make the Earth uninhabitable for humans. In fact, global temperatures would have to rise far above currently projected values to pose a fatal risk to humans. I also argued that with the large amount of resources currently being allocated to climate change, it is one of the least neglected global problems. According to the law of diminishing returns, it does not make sense to allocate more resources to this area. Lastly, I established that humanity is facing larger and more urgent threats to its long-term survival, such as biosecurity risks and unchecked artificial intelligence. Addressing climate change before addressing these problems would be futile and foolish.
Although there are plenty of reasons to assign a lower priority to climate change, I must again stress that we should not abandon the cause altogether. Global warming still poses a serious threat to our quality of life. It does not threaten the survival of humanity as a whole, but it does subject a large number of people to unnecessary suffering. Often, those affected are among the poorest and those contributing the least to climate change. The objective of this paper is not to dissuade climate action. Rather, we must redistribute existing resources to areas within climate science that are known to cause the most serious effects. Once we have cleared our minds of panic, we can begin to make better choices and have a bigger impact. It might be grim, but I leave you with a sense of grim optimism.
This phrasing makes it sounds like you're saying, "Normal people would think climate change is important, but if you're a weirdo who holds these 'effective altruist' values, then you don't think it's important." But your actual claim is more like, "According to normal people's values, climate change isn't as important as they think because they're empirically wrong about how bad it will be." I would remove the reference to EA from the abstract, although I think it's fine to keep it in the first section as an explanation for why you started thinking about the impact of climate change.
I see what you mean, and it definitely warrants rephrasing. Thank you for taking the time out to comment :)
I feel as though there's a bit of a disconnect between the title and the claim being made in the paper. I don't think it's right to characterize climate action as being solely motivated by the risk of human extinction. If it were, then this and other EA arguments against climate focus would be accurate. But if you reframe climate change as "just" a catastrophic event that will cause the tens or hundreds of million deaths, then I don't know that any of the arguments in this essay would actually apply (except that climate change is not neglected, which I accept).
By analogy, imagine if this was an essay titled "The Threat of a Pandemic is Exaggerated" and in the essay you argued that a global pandemic probably wouldn't wipe out the human race, so we shouldn't focus on it. (I know you mention that that's wrong but for the sake of argument assume it's right.) That would be wrong, because unless you are the most fanatical longtermist, the bar for focusing on a cause isn't literally that it should prevent human extinction or bust. Some people who work to prevent pandemics believe that they could literally cause extinction, but you don't have to believe that in order to believe that we should work to prevent pandemics.
In fact, it's probably more productive to compare climate change to other global health and wellbeing ("neartermist") causes. Consider the record storm season in North America in 2021, or the unprecedented heatwaves in India this summer, and it becomes much more sensible to think of climate as a very current issue and not something that only has merit as an x-risk.
Thank you for taking the time out to comment :)
My intention was to evaluate climate change as an x-risk, but I see what you mean about it being much more than that. I think the essay will benefit from additional comments on instead treating it as a current issue.
I'll try to avoid stating anything that has been discussed in other comments and this will be fairly brief. I have a few intuitive problems with the paper:
Thanks for sharing this piece and looking for constructive feedback. I'd agree with most of the points made by other commenters. I would also suggest:
I'm afraid to say there are a lot of room for improvement here. As others have pointed out, most climate justice advocates do not literally think it will wipe out humanity, they think it will kill a large amount of people and make life very bad for others, and want to prevent this for obvious reasons.
But I mainly have to take serious issue with paragraphs like the one here:
There are so, so many things wrong with this paragraph. For starters, you can't expect the effect of mitigation efforts to be instantaneous, it takes time to build things. A nuclear power plant could take 10 years to build, you don't see the mitigation effect for a whole decade. And investments in energy technology research will look worthless for many, many years, until they finally pay off and save huge amounts of emissions.
Secondly, much of these are investments, not donations, so much of that money is not lost. If you put a solar panel on your house (under good conditions), it will pay itself off in several years, and yet this would not be taken into account in your 500 billion figure.
Thirdly, the emissions increasing doesn't mean the money didn't do anything. Emissions always increase if we do nothing to stop them. It is likely the case that emissions would have increased much more if there were no mitigation efforts in place.
fourthly, the whole premise doesn't make sense. If the current amount of money isn't enough to stop emissions rising, thats more of an argument for increasing funding, not decreasing it. Otherwise how would you stop emissions hitting 11 degree doom level? ( of course, the actual answer is that mitigation efforts are working, albeit slowly, but that contradicts your argument).
I have no background in economics, so these insights are extremely valuable to me. Thank you for taking the time out to comment :)
I think this is perhaps quite a simplistic reading of climate change, and whilst somewhat in line with the "community orthodoxy", I think this post and that orthodoxy is somewhat misguided.
Firstly, this post broadly ignores the concept of vulnerabilities and exposures in favour of a pure singular hazard model, which whilst broadly in line with the focus of people like Bostrom and Ord, seems overly reductive. Moreover, it seems highly unlikely that even the most damngerous pandemic would actually cause direct human extinction, nor an ordinary nuclear war, meaning a care about only direct X-Risk really should lead to a prioritisation of omnicidal actor, AI risk, and other speculative risks like physics experiments and selfreplicating nano-technology. Even if you focus on the broader hazards category, climate's role as a risk factor is certainly not to be ignored, in particular I think in increasing risk of conflict and increasing the number of omnicidal actors. It should be noted, however, that X-Risk doesn't just mean human extinction, but anything which irrepairably reduces the potential of humanity.
Once you are dealing with GCRs and societal collapse, and how this might pose an X-Risk (by conversion to irrecoverable societal collapse, which still needs more work on it), climate change rises in priority. Climate change increasing civilisational vulnerability becomes a much more serious issue, and an increase in natural disasters may be enough to cause cascading failures. If you seriously care about the collapse of our complex system, or collapses that result in mass death (not necessarily synonmous), I think these more reductionist arguments hold less sway. Whilst I won't go into the long termist argument for this in detail here, if you think it unlikely that societal recovery is in line with what is good (you might be particularly susceptable to this if you are a moral antirealist who thinks your values are mostly arbitrary ) or that societal recovery is reasonably unlikely. It also should be noted that it seems that societies struggle to recover in unstable climates, so climate change may make it even harder for societal recovery. In the article you say that the ability for climate to cause societal collapse is instead a reason to focus on the relationship between food systems and societal collapse, however climate doesn't just impact our food systems, but a huge amount of our critical systems , and just addressing food supply may lead us still vulnerable to societal collapse. (NB I think these societal collapse tendences of climate change is generally low probability, probably <10%) Climate change related vulnerabilities likely make the conversion of a GCR-> a societal collapse more likely and the conversion from societal collapse->irreversible societal collapse, as well as the conversion of shock-> GCR. Moreover, the literature on systemic risk would probably further elevate the importance of climate change. If you only care about fully wiping humanity out, because you think under almost all scenarios of GCRs/society collapse we recover to the same technological levels + in line with values you agree with, then maybe you can ignore most of this, but I tend to think such an argument is mostly implausible (I won't give this argument here)
On the topic of neglectedness, it is true that climate change as a whole is not neglected. Nonetheless, potentially high impact interventions on climate may (and may is important), still be available and neglected. Thus, don't let this general EA advice disuade you if you think you have found soemthing promising. In relation to the funding given to climate change, a lot of that is related to investment in energy generation technologies, and much pays for itself, although general climate investment is outside my area of expertise. Moreover, it is unclear how much more money on AI Safety would massively help us, although this is once again outside my expertise and I know there is a lot of disagreement on this, so take this paragraph with a little pinch of salt.
Finally, this article general presupposes that X-Risk is high at present and that we are at "the hinge of history," presenting X-Risk work as the only outcome of longtermism. Whilst such may be a common sentiment in the community, it certainly isn't the only perspective. If for example you think X-Risk in general is low, from other longtermist perspectives, it may be the case that the destabilising effects of climate change on the globe and the global economy is indeed highly important, and then you get into the neglectedness question ie is it easier to stop the4 negative effect of climate change on GDP growth (and many interventions probably increase gdp growth as well) or just focus on gdp growth/. This is certainly not a done question, although I think John Halstead did some stuff on it which I probably need to check.
Whilst I certainly think your argument is useful in parts, including the claim that climate change is probably overhyped, I nonetheless feel you unreasonably suggest climate change is less of an issue than it is. Less focus on the Bostrom/Ord -esque existential hazards may be beneficial, and a greater diversification of viewpoints, including better integration of some of the arguments that the references you cite make.
However, please don't let the overall critical tone of this comment dissuade you- its awesome to see people new to EA writing such genuinely well researched and well written posts on the forum (I certainly haven't had the bravery to post something on here yet!) Keep up the good work despite my critiscms.
"They conclude that temperatures can rise to 11 degrees Celsius before the share of uninhabitable areas begins to include most of today’s population. Even at 10 degrees Celsius, the damage is equivalent only to a recession that would set us back by 20 years. However, this still does not imply extinction."
Do I understand you right, that they conclude that a rise of global average temperatures by 11 degrees Celsius will then begin to make uninhabitable areas of locations currently inhabited by people?
I'm not sure what OP meant, but what you said is bound to be false - some cities are going to be flooded much before we hit 11 degrees warming, and if I'm not mistaken also currently fertile areas will become deserts (maybe most of my country's non-desert area?) by that point.
yes, but I wonder if my restatement is a correct interpretation of what the OP meant.
Yes, that is what I meant to say. The paper I've cited is in the references at the end if you're interested in looking into it.
Thank you for taking the time out to comment :)
You are welcome.
I have seen plenty of discussion from climate scientists warning against comparing the Anthropocene with earlier geologic time periods, and comparing humans with mammals alive during an earlier period is not an apples-to-apples comparison.
FYI, I believe that locking in a rise in global avg temperature of 14C can happen within a 100-year time frame. If it happens, Earth will certainly be uninhabitable but the mammals could all be dead before then.
My hopes for our long-term future rest with engineering technology that doesn't exist yet.