Summary: How to factor climate change into our efforts to make the world a better place. For people new to climate change and experts alike. Includes what to do on climate change if you are focused on a different cause. Bottom line: everyone should have climate change in their portfolio of causes, though not necessarily as their primary focus. Details include how to reduce your own emissions, influencing society’s emissions, and career options.

Opening Remarks

What is this post and how should you read it?

This post is how I think people should think about climate change, especially people trying to make the world^[1] a better place.

It’s written for a few audiences:

• Anyone with a general interest in climate change: Are you familiar with the idea that climate change is a thing that’s happening, is considered to be a problem, and has something to do with greenhouse gases (GHGs)? If so, you’re ready to read this post. The career advice at the end is more specialized, but most of the post is written for you, especially to help you account for climate change in your efforts to make the world a better place.
• Climate Experts: There will likely be some details of interest throughout, perhaps especially in the career advice section, though much of the content will be familiar. I would also read this for ideas on how to talk about climate change to wider audiences. Notice e.g. how I frame things, what specifics I discuss, and also what specifics I don’t discuss (e.g., almost the entirety of climate science & impacts). I see a lot of content from climate experts that, in my view, do these things poorly. And please chime in with anything you have to add, contest, etc.
• People focused on other causes, including other global catastrophic risks and existential risks (GCRs/XRisks)^[2]: The post makes some important points about how to engage with climate change itself and especially the field of people working on climate change. This should be worth your time. See in particular the section “It’s fine to focus on other issues, but please do so respectfully”, and also the section “Persuasion”.

Some of the content is addressed to effective altruism (EA), but most of it is relevant to anyone regardless of their involvement in EA. In case you’re not familiar with EA, it’s a community of people working to make the world a better place as well as they can, or at least to do things along those lines.

Outline and main ideas

This post has four main sections:

• Climate Change Fundamentals: The main point is that it is good to reduce GHG emissions. That—and not other aspects of climate change—should be front and center, at least for most of the likely audience of this post. There’s a lot of uncertainty about how hard we should try to reduce emissions, but everyone can and should take some actions for emissions reduction. Also, the world as a whole should aim for net zero total emissions, but getting there is very difficult. Indeed, addressing climate change may be orders of magnitude more difficult than addressing other GCRs/XRisks. That means the world should be investing more in addressing climate change—but we arguably should be investing less. Finally, those who are focused primarily on other issues should still speak positively about the importance of climate change.
• General principles for reducing greenhouse gas emissions: Most generally, we should look for opportunities to reduce emissions that are “cost-effective” in the sense of reducing more emissions for less money, less time, less stress, etc. Specific opportunities can influence both supply and demand, such as shifting the energy supply from fossil fuels to nuclear/renewables and reducing energy demand. It can also include reducing both one’s own individual emissions and the emissions of larger populations. Often, the transition is the hard part: many opportunities are difficult/expensive at first but get easier/cheaper over time. Finally, exactly what to do will vary from person to person.
• Specific opportunities for reducing greenhouse gas emissions: For reducing one’s own individual emissions, the best opportunities are plant-based diets, urban lifestyles or similar (e.g., living without a car), and avoiding air travel. It is sometimes proposed that the best way to reduce one’s own emissions is to abstain from having children, but that raises thorny ethical issues and is not recommended. We can also influence other people’s emissions, in particular by persuading other people to reduce emissions, by advancing public policies that reduce emissions, and by helping the transition to clean energy systems. Some more specialized opportunities are not covered, such as regarding cement and refrigerants.
• Climate change careers: It helps to have an interdisciplinary training, but this is not strictly necessary. There are great opportunities for people with skill sets in engineering, public communication, business/finance, natural and social science, and for people who can do a bit of everything. There are also good opportunities for people with climate change backgrounds seeking to transition to work on other topics; specific opportunities discuss are on GCR/XRisk, AI governance, and nuclear winter. The section ends with some brief remarks on philanthropy.

Some personal background

I’ve worked on climate change on and off for about 15 years. It was the focus of my Ph.D. dissertation. I also designed and taught an undergraduate sustainability class; some ideas from that class are incorporated into this post. Since the Ph.D., I’ve mainly worked on other topics through my role at the Global Catastrophic Risk Institute. I’ve taken a renewed interest in climate change recently, prompted by various recent publications, extreme weather events, and personal factors. I have a critique of the climate change discussion in my review of The Precipice, which has a lot of great content but I think significantly understates the risk. 

I’m glad to see recent interest in climate change on the EA Forum (e.g., 1, 2, 3, 4, 5, 6; also slightly earlier posts 1, 2, 3, 4, and probably also a few others I’m missing). There’s been a lot of great discussion. However, I think it’s missing a certain perspective, which I attempt to articulate here. In particular, I see a need for more emphasis on the practical actions that different people could and maybe should be taking to address climate change.

I don’t know everything there is to know about climate change. Many people know more than I do. I’m sure some of them could fill in details that I’ve missed, or maybe even correct some mistakes. That said, I do believe the content here to be overall reliable.

Climate Change Fundamentals

It is good to reduce greenhouse gas emissions

If you get nothing else out of this post, get this: all else equal, it is good to reduce greenhouse gas emissions.

This is hopefully an obvious point. There is essentially zero debate about this, bad faith actors notwithstanding. The only meaningful debate is on how to reduce emissions, including questions of whether certain actions to reduce emissions are worth whatever sacrifice they entail.

I worry that this basic point gets lost in many discussions of climate change. Instead, they focus on climate change itself, including the underlying science and the risks it poses to the world. These things can be important, but only to the extent that they inform the decisions people face, especially on reducing greenhouse gas emissions. I worry that in focusing on climate change itself, the opportunities and decisions get lost in the shuffle. As a consequence, people may end up failing to recognize their opportunities and making worse decisions, with inferior outcomes for the world.

This is definitely not just an EA problem. It’s widespread. A classic example is the film An Inconvenient Truth, which was almost entirely on the science of climate change, with only a brief, simplistic discussion of solutions tacked on at the end. Also, the EA space is certainly not uniformly guilty of this. For example, EA analyses of climate change philanthropy (1,2) strike me as quite constructive. But I do see room for improvement.

In focusing on emissions reduction, this post could perhaps be criticized for having carbon tunnel vision and not a more holistic perspective on environmental sustainability. I certainly agree that holism is important. Perhaps there could be value to a future post on the entirety of environmental sustainability. That said, specific actions to reduce emissions often also help on other environmental issues. Furthermore, for the likely audience of this post, I believe a focus on emissions is appropriate instead of a focus on how to adapt to climate change because it is likely to have better opportunities for emissions reduction and because emissions reduction is, in my view, more pertinent to GCR/XRisk.^[3] That said, people focused on addressing global poverty may benefit from attention to climate change adaptation. Finally, geoengineering is discussed briefly toward the end.

The value of emissions reduction is uncertain but potentially large

The value of emissions reduction comes from the harm that a given amount of emissions would cause. Each chunk of emissions makes climate change more intense by some amount, increasing the harms. The more bad those harms would be, the more valuable it is to reduce emissions.

It is important to think in terms of the value of avoiding some chunk of emissions. That is the relevant parameter for decision-making purposes. It’s easy to get caught up in questions of how bad climate change may be if the world as a whole emits some amount of emissions. However, you are not the world as a whole and you do not face the decision of whether to emit all those emissions. We can influence societal emissions—more on that below—but even then it’s still important to think in terms of some chunk of emissions and not the whole thing.

So, how good would it be to avoid some chunk of emissions? In short: we don’t know.

Any given chunk of emissions can have a variety of potential harms. It can help to organize them into three categories:

• Disruptive harms: The chunk of emissions contributes to massive disruption across the world, but civilization endures.
• Catastrophic harms: The chunk of emissions contributes to the collapse of civilization or worse.^[4]
• Wildcard mild harms: The chunk of emissions contributes to harms that are fairly small.

The disruptive harms are the standard expectations of mainstream climate change research. They involve scenarios that can be quite bad, with suffering potentially at a massive scale. The 2022 northern summer is illustrative: intense heat waves across the northern hemisphere, some with severe droughts, plus severe flooding in Pakistan. This and more all project to get a lot worse. In the words of Katharine Hayhoe, a top climate scientist and communicator, “Our civilisation was constructed for a climate that no longer exists” (1). Finally, these disruptive harms may affect many future generations because CO2 emissions can remain in the atmosphere for centuries or longer (1, 2).

The catastrophic harms are those studied by people interested in climate change as a GCR/Xrisk. The research is limited (1, 2, 3, 4, 5, 6, 7), but for now, the basic picture seems to be of some chance of climate change contributing to global/existential catastrophe. The size of the effect is a point of debate. My sense is that it’s being underestimated, but it’s difficult to pin down.

The wildcard mild harms are ones in which some major change happens that renders emissions relatively unimportant. It could be a massive energy breakthrough, like solving fusion power. It could be some other radical technological change, such as an AI singularity. Or it could be some other catastrophe, such as a nuclear war. Any of these could drown out the effects of greenhouse gas emissions if and when they occur.

Any given chunk of emissions contributes harms proportionate to the size of the chunk. Your own personal emissions do not single-handedly cause suffering at a massive scale, but they do play a role, or at least they may under disruptive climate change scenarios.

Here is how I would think about any given action to reduce emissions. The default expectation is that the action is helping to avoid disruptive harms, which may be quite large. There is some chance of the action helping to avoid extreme catastrophe. And there is some chance that the action will end up only helping to avoid relatively small harms. The exact balance of these possibilities is difficult to assess.

Notice that under all these various possibilities, it is still good to reduce greenhouse gas emissions. Therefore: It is good to reduce greenhouse gas emissions, and it might be very good.

One final detail. There is a line of economics research attempting to quantify the dollar value of GHG emissions, known as the “social cost of carbon”. The SCC research was a primary focus of my Ph.D. studies. I left that feeling overwhelmingly skeptical of SCC research due to its false precision, questionable assumptions, and an inappropriate cost-benefit framework. It seemed to generally understate the value of emissions reduction. I haven’t kept up with the literature but I see that current estimates vary from tens to hundreds or even thousands of dollars per ton CO2 emissions. For comparison, one ton of CO2 emissions is comparable to one person taking a regular commercial flight from New York to London. I wouldn’t use SCC research as any sort of precise guide, but it does provide an additional point of information.

Climate change warrants massive investment—but not necessarily ours

It’s important to distinguish between what should we do with our resources and what should society do with its resources. Those are, for the most part, two different things. Note that the resources here can include time, money, attention, and other things.

Out of all the major global risks, climate change may get the most investment—but it may also need the most investment.

Currently, annual global GHG emissions are about 50 billion tons of “CO2 equivalent”. That includes 35 billion tons of actual CO2, plus other greenhouses, such as methane, in a quantity that has an aggregate warming effect comparable to an additional 15 billion tons of CO2. These various molecules eventually fall back out of the atmosphere, but it’s a slow process. For CO2, it takes centuries or longer. So, to stop the warming, the world needs to go from 50 billion to zero.^[5]

Getting anywhere near zero will be very difficult. It involves restructuring a large portion of the entire global industrial economy. It may require a lot of technology that doesn’t exist yet, widespread changes in living patterns, massive financial investment, social and political will, and more. The scale of the problem is enormous.

Other GCRs/XRisks, such as AI, pandemics/biotechnology, and nuclear weapons, do not have this characteristic. They do all require significant effort and investment. More can and should be done. However, the quantity of investment needed would appear to be multiple orders of magnitude smaller.^[6] If that is indeed correct, then we can conclude: Society should make large investments in addressing all of the GCRs/XRisks—and make a much larger investment in addressing climate change.

Unfortunately, society is not making all of these various investments, and its investments are not always well-targeted. That leaves room for us to make a difference. Because emissions reduction is so difficult, we may often have better opportunities on other GCRs/XRisks. However, some opportunities to reduce emissions can still be better than some opportunities on other GCRs/XRisks. The tradeoff is difficult to evaluate due to deep uncertainty about all of the GCRs/XRisks (1, 2, 3, 4).

There are two easy cases:

• When our resources are not scarce, such that reducing emissions doesn’t detract from our work on other issues. This is discussed further in the next section.
• When we have other reasons to allocate resources to emissions reduction, e.g. when it leads to other opportunities, such that work on emissions reduction also advances our work on other issues. An example is discussed in the section on policy.

Everyone should have emissions reduction in their portfolio of doing good

For climate change, a portfolio approach works better than a cause prioritization approach.

• Cause prioritization approach: An actor (an individual, group, etc.) identifies the most important issue and works on that.
• Portfolio approach: An actor works across multiple issues.

A lot of analysis on climate change seems to be motivated by a cause prioritization approach. For example, research may assess whether climate change is a GCR/XRisk, and if it is, how large of a GCR/XRisk it is compared to other GCRs/XRisks. That sort of comparison can inform cause prioritization, though even then, the comparison should be between the opportunities to reduce the risks, not between the size of the risks themselves. However, this sort of comparison is unnecessary for a lot of action to address climate change.

Especially within the space of GCRs/XRisks, climate change is distinctive in the wide variety of opportunities to reduce the risk. Tomorrow, you will probably not launch any nuclear weapons, but you will emit greenhouse gases.

Cause prioritization—or better yet, opportunity prioritization—is appropriate when there are tradeoffs between causes/opportunities. You cannot use the same hour to work on both A and B and you cannot use the same dollar to donate to both A and B (unless you give both half an hour or fifty cents, but you get the idea). However, this reasoning does not always apply to GHG emissions reduction.

To see why, here’s an analysis of turning lights off. To those of you who already know that this is not the most impactful action, relax, will get to the big things later.

Thought experiment: “the light switch”. Suppose, hypothetically, that you are the only person in a room. It is nighttime, and the light is on. Then, something comes up, and you find yourself compelled to leave the room and go somewhere else. As you leave the room, you have the option of turning the light off. To do this, you need to raise your arm and flip a switch. During that brief moment, you had nothing else to do with that arm of yours.

I am joking a bit here in labeling this as a thought experiment. Of course, we have all been in this situation many times. However, it is good illustration of a more general point.

The point is that this action helps on climate change and has essentially zero downside. It helps climate change because it reduces electricity consumption, which generally results in reduced GHG emissions. The action has essentially zero downside because in that moment, you might as well turn off the light. Your arm wasn’t doing anything else. It was not a scarce resource whose usage needed to be prioritized across different causes or opportunities. 

The decision to switch the light off is easy. You don’t have to worry about how severe climate change may be, whether it could cause global/existential catastrophe, or how important that may be compared to other risks or other cause areas. You can just flip the switch.

If you are already turning off lights because (or at least in part because) of climate change, then congratulations, you already have climate change in your portfolio of actions to make the world a better place. It might not be an important item in your portfolio, but it is there, as well it should be. Indeed, the GHG benefits of turning off lights are small relative to some other opportunities discussed below. I’ve used it here because it’s such a clear example of how we can all readily include emissions reduction our portfolios.

It’s fine to focus on other issues, but please do so respectfully

The portfolio approach has its limits. We still need to decide what to dedicate our careers to, or our funds, etc.

Should GHG emissions reduction be one’s top cause? For some people, perhaps, for other people, perhaps not. Speaking for myself, emissions reduction has not been my primary focus since I finished my Ph.D. (and a short post-doc after that), though it remains within my portfolio at GCRI and I have been trending more nervous about climate change.

For those who are focused on other causes, it’s still important to speak positively about the importance of climate change and emissions reduction, for two reasons:

(1) Encouraging other people to reduce emissions, including through actions (such as turning off lights) that don’t interfere with them contributing to other causes.

(2) Generating interest and respect from people who are more focused on climate change, or who at least are more concerned about it.

Both items are important, including for EA.

Regarding item (1), EA is getting a decent amount of attention these days, which means more opportunity to encourage other people to reduce emissions. See the section below on persuasion.

Regarding item (2), this quote is an illustration of how things can go wrong:

“The biggest issue I have with EA is the lack of attention to climate change. I am supporter and member of the EA but I take issue with the lack of attention to climate change. Add me to the category of people that are turned off from the community because it's weak stance of climate change.” (Link, see also this.)

I have also seen this sort of reaction from people I have worked with. That includes some people of considerable importance within government, academia, etc. For these people, climate change seems to obviously be a very important global problem. When they see people in the GCR/XRisk space dismissing the importance of climate change, they are turned off. We lose credibility and influence.

It’s especially unfortunate because people working on climate change are natural allies. Climate change is a complex, large-scale, global, long-term issue. It can take a high degree of altruism to focus on climate change, and a high degree of aptitude. We should want these people on our side, for whatever it is we are working for.

I personally don’t like the “information hazard” terminology, but that type of concept is applicable in this context. Fortunately, it’s not hard to phrase things well. To wit:

Bad rhetoric: Climate change is a low priority and it is wrong to focus on it.

Good rhetoric: Climate change is important and it’s great that people are working on it, but I see even better opportunities on other issues. (Could also say “better opportunities for myself, or for people with certain backgrounds, etc.”)

I have had many conversations like this with people focused on climate change and I have never gotten any negative reaction from the “good rhetoric”. They understand that climate change is not the only issue in the world. Indeed, many of them have interdisciplinary backgrounds in which working across issues is standard practice. They might not immediately switch to your preferred issue, but you’ve at least planted the seed in their mind and left them with a favorable impression. Sometimes that’s all we can do. And for them, climate change may well be where their best opportunities lie. These things can vary from person to person.

Climate change is important. Reducing greenhouse gas emissions is good. We can and should say these things, even if we are mainly focused on other issues.

General principles for reducing greenhouse gas emissions

An EA perspective can be valuable for crafting opportunities to reduce GHG emissions. We should be looking for “cost-effective” opportunities that reduce more emissions for less money, less time, less stress, etc.

Here are some other general principles for developing opportunities to reduce emissions.

Demand-side and supply-side actions are important and synergistic

GHG emissions are largely a matter of supply and demand:

• The supply side: The production of energy, food, cement, refrigerants, and other sources of GHGs. Actions include things like switching from fossil fuels to nuclear & renewables.
• Demand side: The acquisition and consumption of products that are sources of GHGs. Actions include things like not using as much energy.

One might think that supply-side actions are more important because they can be done at scale and don’t require behavioral change. Or, one might think that demand-side actions are more important because they are more widely accessible to people trying to make a difference. In fact, both can be important (1, 2, 3).

They are also synergistic with each other. It is easier to build a clean energy system if demand for energy is low. Ditto for other sources of GHGs.

This post has some emphasis on demand-side actions for the benefit of a general audience of people trying to make the world a better place. There are some supply-side details that a general audience should know; see the section on clean energy systems. Toward the end there’s also some discussion of supply-side actions written more for specialists.

Individual and collective actions are synergistic

Actions to reduce GHG emissions can be categorized as individual or collective:

• Individual actions: Actions to reduce one’s own personal emissions.
• Collective actions: Actions to reduce the emissions of some larger number of people.

It’s common to find arguments against individual action (here’s one). It’s said to be “a drop in the bucket”, shifting blame from institutions (e.g., fossil fuel corporations) to individuals, and a distraction from larger-scale collective action.

I think this is mostly wrong. A drop in the bucket might only be a small amount of good, but it’s still good. For comparison, someone’s donation to a poverty charity might not end poverty, but it still helps some poor people, and that is good. Regarding blame, any blame must be shared between corporations and their customers (among others). The point about distraction is sometimes valid, though the reverse can also hold: people who take individual actions may do more on collective actions. For those of us with a high motivation to make the world a better place, we’re more likely to do both. 

Here is an example of the synergy that can exist between individual and collective action: Eric Adams became vegan, then wrote a book about it, then advocated for “Meatless Mondays” in public schools in his capacity as Borough President of Brooklyn and then Mayor of New York City.^[7]

We might not all have such a high degree of social and policy influence, but we can all have some.

Also, some of us are primarily focused on other causes. A critic of individual action might say “I don’t care how green you are. I want you in the movement for climate justice” (link, echoed by a top climate change researcher here). However, this doesn’t make sense if you’re already dedicated to some other cause (global poverty, AI safety, etc.) and don’t plan to switch. You may not have space in your life to join the climate justice movement, or to pursue other time-consuming climate change activities. But you can still take some individual actions, and maybe some more feasible collective actions. If that’s what you’re able to do, great, do it, and don’t let anyone tell you you’ve got it wrong.

The transition is often the hard part

A lot of opportunities to reduce GHG emissions have relatively large upfront costs of one sort or another, but become easier over time.

• Capital investment. Purchasing (for example) an electric bicycle is an upfront cost, but it can save you money over time if you use it instead of a car, and can even bring a net profit if you later decide to sell the car.
• Behavior change. Learning (for example) how to get around via e-bike can take some effort, but once you’ve got the hang of it, it may become relatively effortless.
• Social situations. Becoming (for example) an outspoken advocate for emissions reductions can change your experience in social situations, bringing discomfort, but after a while you may adjust to it and it becomes more comfortable.

I still remember when I went vegetarian back in undergrad. That was in Rochester, New York, where the buffalo wings were amazing and my friends made sure I knew it. It was awkward at first, but after not too long it became routine. This sort of experience seems pretty common, buffalo wings notwithstanding.

One can live quite well with low GHG emissions. That’s been many people’s personal experiences, myself included. There’s even research documenting this.

When the costs go down over time, the case for taking the action is more compelling.

The optimal actions will vary from person to person

General-purpose risk and decision analysis can inform our decisions, but a lot will need to be done on a case-by-case basis, for two reasons:

Disagreement on the value of emissions reduction. In theory, we arguably should agree, but in practice we don’t. That much is apparent from the ongoing debate about climate change in the research literature, EA forum posts, etc.^[8]Therefore, each of us will need to decide for ourselves how valuable we think GHG emissions reduction is.

Our own personal characteristics. A lot of opportunities to reduce GHG emissions are deeply personal: where we live, what food we eat, etc. General-purpose analysis can provide some guidance on these matters. We also can and should try to support each other on our decisions. Ultimately, though, we’ll each need to judge for ourselves how a given action would affect our lives and what we’re comfortable doing.

For example, the discussion below has some emphasis on urban issues, which happen to be a longstanding interest of mine. Urban issues are certainly important for emissions reduction, but I probably wouldn’t be saying as much about them if I didn’t coincidentally have that interest. Because of this interest, my optimal actions may include more emphasis on urban issues than people who don’t share this interest.

Specific opportunities for reducing greenhouse gas emissions

This section covers what are, to my knowledge, the best ways of reducing emissions. There’s a massive amount of research on this and I’m not up to speed on it all, but I do believe the basic ideas check out. The ideas can be grouped as follows:

• Individual actions: plant-based diets, urban lifestyles (or similar), and avoiding air travel. I also discuss having children, which is sometimes said to be important, but it raises thorny issues.^[9]
• Collective actions: persuasion, policy, and energy systems. I am omitting some more specialized opportunities, such as regarding cement and refrigerants, because they’re arguably less relevant for a general audience and because I just don’t know much about them, my apologies—but see the links if you’re interested.

It’s good to understand the basics of all of these so that you can seek out the best opportunities for yourself given your own personal circumstances and your degree of concern about climate change.

Plant-based diets

This one’s simple. Vegan is best, but a “veganish” approximation is still very good. Clearly, there are also other worthy reasons to favor a plant-based diet, such as for nonhuman animal welfare. For GHG emissions, the difference between plant-based and animal-based foods is quite large. I know a lot of you are already vegan or veganish. Keep up the good work!

If you’re ambitious, you could figure out which plant-based foods are the best or account for other factors such as food miles, though these factors are generally smaller. Personally, I am not that ambitious, so I focus on just eating vegan. I’m not a perfect vegan, but I do OK. We shouldn’t beat ourselves up over not being perfect—we need that emotional energy for everything else we’re working on.

Urban lifestyles (or similar)

This one’s more interesting. We know that cars need a lot of energy. Electric cars can be helpful, but most electric grids use fossil fuels, and even on a decarbonized grid, there can be value in reducing the load. So it’s good to skip the car, but that can be difficult if you live in a car-centric place. And so, it really helps to live in a not-car-centric place. Additionally, if you live in an apartment, you’re sharing walls with other units, which requires less energy to heat in the winter. There are also other benefits like reduced travel of vehicles delivering you mail, packages, etc. And if you live in a smaller unit, you’ll need less air conditioning in the summer, and you may end up buying less stuff (because where would you put it?). You may even waste less food because you can easily grocery shop so often that you only buy what you need. Food waste is actually a pretty big problem, though it’s a proportionately smaller problem if you’re vegan(ish).

Why the “or similar”: A low-carbon lifestyle does not require living in a city. Indeed, worldwide the lowest-carbon lives are often rural, living on local resources etc. It’s also possible to live low-carbon in plenty of towns, villages, and even some suburbs. But for many of us, it will work best to be somewhere more urban.

Many people, myself included, enjoy the urban, car-free or car-light lifestyle and have lots of experience with it. If you’re thinking of making the switch, there are a lot of resources out there to help you with this.

Also: electric bicycles, including cargo bicycles, to replace cars. Seriously, this a major revolution in transportation. A lot of people have succeeded at using e-bikes instead of cars (e.g., USA, Netherlands). Don’t let anyone tell you it’s “cheating” if you don’t pedal. Just try, if at all possible, to live somewhere with safe cycling infrastructure. A literature review across OECD countries found, “The leading barriers [to cycling] related to riding on the road alongside motor vehicles.” Makes sense to me. At a minimum, it’s good for you to not be using one of those motor vehicles out there threatening the cyclists.

Avoiding airplane travel

It takes a lot of energy to get a plane into the air. It is also extremely difficult to decarbonize aviation. Electric power just doesn’t work well for airplanes. So, avoiding plane flights is a big way to reduce emissions. Indeed, even a single plane flight could end up constituting the majority of your annual personal GHG emissions (1, 2). Some climate change researchers have stopped flying, even at the expense of missing out on conferences and other activities. Personally, I am considering the same for myself, though I recognize that in some cases flying can be worth it. For example, if I ever have the chance to fly somewhere for some diplomatic summit to defuse a geopolitical crisis, then yes, I would definitely take the flight. I’d hope you would too. For more modest travel opportunities, I find it hard to judge. Some air travel can be important, but those emissions really are quite high.

Remote interaction can help a lot. We all now have plenty of experience with remote interaction (thank you, COVID-19), but, speaking for myself personally, I still feel like I’ve only scratched the surface. There are tools out there that I haven’t really put to the test, such as proximity chat (e.g., Gather). Some of you may be a lot more experienced at this. GCRI has always been remote, and we run a remote Advising and Collaboration Program, but we’re not set up to organize anything more substantial like a remote conference. However, if someone else is doing the organizing, I for one would be interested in participating. Yes, remote meetings have well-known disadvantages, though they also have advantages including lower cost, reduced time commitment, and inclusivity (e.g., to parents of young children and people from countries with visa restrictions). Personally, I generally avoid traveling even short distances to in-person meetings because I can’t justify the time, but I accept lots of invitations to remote meetings. It seems good to try maxing out the value of remote meetings to reduce the need for in-person meetings, especially those that would require airplane travel.

This does raise difficult questions such as regarding events like EA Global. In terms of GHG emissions, a plane flight to EAG matters a lot more than, say, eating vegan while you’re there. Of course, flights to EAG also have benefits that could plausibly outweigh the harms in at least some cases. EAG organizers and attendees should take the air travel carbon footprint into account. Related: check out EAGxVirtual 2022. I’m pretty excited about this. If this can be a good event, then it could pave the way for more low-carbon EA community interaction.

Also: if possible, try living somewhere with enough nearby that you have less reason to fly.

Having children

Yes, any children you have will emit greenhouse gases, perhaps quite a lot. But this is a thorny matter.

Ultimately, people are more important than GHGs. We should only be reducing emissions to the extent that doing so is good for people, and good for nonhuman animals and whatever else we might care about. Fewer people does mean less GHG emissions, but we should be optimizing for people, not for GHGs. A world without people would be “great” for climate change but terrible overall.

It is possible for a population to be suboptimally large, such as when it exceeds its carrying capacity, precipitating collapse. There are analyses finding that the human population is currently exceeding its carrying capacity. However, even if this is true (I don’t know), it’s a function of both population size and how people are living. Would the world be better with fewer people consuming more or more people consuming less?

Also—if it’s bad to have children, should we also try to cull the current population down to a more sustainable size? That seems like a pretty clear no.

Personally, I have a very hard time advising anyone to not have children because of the GHG emissions. It’s such a deeply personal decision. Also, I would think that anyone conscientious enough to even consider this may tend to raise children who become future leaders of important global issues.^[10] So, if you’re considering having children, it’s fine to take GHG emissions into account, but I wouldn’t feel pressured over it.

Persuasion

Persuading other people to act multiplies your impact. Here it helps to have positive rhetoric about climate change, to take enough actions yourself so as to be a good role model and not a hypocrite, and to have a good understanding of how to reduce emissions. That includes both the technical dimensions—which types of actions are high-impact—and the personal dimensions—what is it like to actually do these things.

As always: know your audience. Figure out what they care about and work with that. In some cases, it can even help to focus on something other than climate change, i.e. “co-benefits”. Maybe someone doesn’t care much about climate change, but they’re on a tight budget and had never heard of e-bikes before. Maybe someone just needs to learn a few good vegan recipes.^[11] Whatever it may be, tapping into that can help.

Some of the opportunity is less about persuading specific people to do specific things and more about changing shared cultural norms and values. A big one is car-centrism. Here in the United States, it is commonly assumed that cars are the way. Ditto for some other places. Getting people to contemplate alternatives can be difficult. But, there is a case to be made that cars ruin cities and that a better world is possible.^[12] These are public conversations worth having.

Persuasion may be a good activity for the EA space to take on. EA has a sizable audience. Including emissions reduction in EA messaging could go a long way at relatively low expense.

There is high value to persuasion by people focused on other issues. If climate change is the main issue you’re focused on, people may discount your message: “Oh, she’s just saying that because she’s a climate change person.” If you have a different focus, your words may carry more weight: “She’s focused on X, but she still thinks emissions reduction is that important? That sounds serious.” You’ll also have access to audiences that are less accustomed to hearing emissions reduction messages. I speak from experience on this as someone mostly focused on other issues.

Policy

Getting policy wins can be a large impact. It’s no surprise that two EA climate philanthropy analyses both emphasize policy. Some people will even argue that policy is the only important action, though I think that’s mistaken. Everything helps, and there are synergies. For example, there’s less reason to oppose a carbon tax if one is already not emitting much carbon. (A carbon tax is a tax on GHG emissions.)

It can help to be creative about what counts as climate policy. The obvious ones are the big national policies explicitly targeted at climate change, such as the US Inflation Reduction Act of 2022. If you have opportunities to help enact these policies, then by all means, go for it. However, many other policies also affect GHG emissions, and some of these may present better opportunities to make a difference. Housing policy is climate policy. Transportation policy is climate policy.^[13] Agriculture policy is climate policy. And so on. A lot of the relevant policy is local (city, state, etc.). Compared to national policy, the stakes of local policy may be lower but it may be easier for you to make a difference, such that it’s a better overall opportunity. (In EA jargon, less impactful but more tractable and neglected.)

Housing policy is a good example. In the US (and possibly other places), demand for a low-emission urban lifestyle exceeds the supply. There aren’t many places where one can live well without a car, and they tend to be expensive. Policies to increase the urban housing supply could help with this. For the most part, it wouldn’t even be a sacrifice—to the contrary, it would benefit the city economically, environmentally (via reduced air pollution), for homelessness, and more. The challenge is overcoming legacy zoning laws and NIMBYism. Indeed, EA groups have previously expressed some support for land use reform to increase the housing supply (YIMBYism; 1, 2, 3, 4). The EA analysis finds land use reform to be a promising cause, and that’s without even considering the substantial benefits for GHG emissions reduction. YIMBYism is already changing some policy (e.g., California AB 2011 and AB 2097); more could be done.

Policy advocacy can be time consuming and it’s not for everyone. With that in mind:

If you are considering running for office, consider an emphasis on the intersection of urban issues and climate change.

EAs have recently started dabbling in electoral politics, in particular via the candidacy of Carrick Flynn. Policymaking is important, and I for one encourage this especially if the pitfalls of partisanship can be avoided. However, to get elected, it’s important to have good standing within one’s district. The intersection of urban politics and climate change could be one of the best ways of connecting with a district while maintaining involvement in a more global, altruistic cause. Furthermore, despite climate change’s global scope, it is a salient political issue in many places. It’s a win-win.

Some cities have undergone rapid, transformative change from cars to other modes. I believe the first was Pontevedra, Spain. Others include Ljubljana, Slovenia, Ghent, Belgium, and most recently Paris. Birmingham has plans in the works.^[14] A running theme is that in the run-up, it looks like political suicide, but once the schemes are implemented, they’re popular and the politicians get reelected. It seems worth finding and supporting politicians who are willing to gamble their careers on this sort of transformative change.

Clean energy systems

Supply-side activities like clean energy are more the domain of professionals, but there are some basic points about energy systems that are good for everyone to know:

• The cost of wind, solar, and batteries has declined dramatically in recent decades, and it’s receiving massive investment. This is among the biggest pieces of good news for the world.
• The medical harms of nuclear fission power are tragically overestimated. Fission power could reduce a large portion of GHG emissions, but it hasn’t and it probably won’t, and it’s because of this.
• There are a few wildcard, moonshot solutions, including nuclear fusion power and geothermal. If they pan out, great, and they may be worthy of public investment, but meanwhile, we can’t count on them.

The misperception of fission power risk is a vivid illustration of how energy systems are social and political affairs and not just engineering problems. Another example is wind power proposals that fail because locals (NIMBYs) don’t like their appearance. Changing these perceptions and attitudes is an important way to support clean energy.

According to the International Energy Agency, “Spending on solar PV, batteries and electric vehicles is now growing at rates consistent with reaching global net zero emissions by 2050” (link). That’s really important. However, it remains to be seen how much this spending will actually continue and how much it will translate into actual decarbonization, especially in the face of NIMBYism and similar social and political resistance. The climate change problem has not yet been solved.

Climate change careers

The ideas listed here are mostly about emissions reduction, but there’s a bit on “geoengineering”, meaning either removing CO2 from the atmosphere or blocking incoming sunlight to lower surface temperatures, and also something on adaptation to extreme climate change.

This is one area in which my own limited knowledge is salient. I expect that other people active on climate change would have additional good ideas. I’ll keep an eye out for them in the comments.

What to study to prepare for careers in climate change

See also my Common Points of Advice for Students and Early-Career Professionals Interested in Global Catastrophic Risk.

My default advice is to pursue something interdisciplinary, especially to bridge the divide between (A) humanities-social science-policy and (B) engineering-natural science. That keeps your options open and positions you for a range of high-value activities. It’s also solid training for other important topics in case you later want to switch to something else besides climate change. Programs to look into include geography, environmental studies, technology policy, and science & technology studies. I did geography and I’ve worked with people from all of the other fields. Each of the fields is great. I would go with whatever you feel fits you best.

That said, climate change is such an interdisciplinary, multifaceted topic that you can study virtually anything and find a way to apply it. Also check out the career ideas below and consider deriving a course of study from that.

Careers in climate change

My perspective on this is somewhat different from the career advice from 80,000 Hours. Here’s how I would look at it:

• For engineers: Pursue R&D on clean energy systems, or maybe carbon removal or solar geoengineering. Decide based on your skill set and your analysis of the specific opportunities. Clean energy systems may be best for those who also have a business orientation because that’s what’s being deployed at scale right now. Carbon removal could be good for those with an orientation toward basic research, though also consider moonshot energy technologies. Solar geoengineering could be good for those with an orientation to ethics and risk analysis. Solar geoengineering could pose major risks (1, 2), but it could also have high positive value if deployed responsibly.^[15] Perhaps you could help ensure the latter. One other idea: transportation engineering. At least in the US, transportation engineers are, as far as I can tell, typically part of the problem, promoting car-centric urban design at the expense of public health and safety and increasing GHG emissions, though (1, 2, 3). There may be opportunities to shift the entire field in a better direction, which could be a high-value opportunity.
• For talented communicators: Pursue some combination of public advocacy and electoral politics. Decide based on personal circumstance, such as whether you could plausibly get elected to certain offices. For public advocacy, there is a role for increasing attention to climate change, but I would encourage an emphasis on solutions, especially solutions public perceptions are an important factor. Could you take on public misperception of nuclear fission risk, or car culture, or NIMBYism? Those would be big wins. For electoral politics, develop policy concepts and rhetoric that would be impactful on emissions and that would resonate with people in your district. And then go get elected, or go get someone else elected and make sure you have their ear. Along the way, try to avoid turning EA and GCR/XRisk into politically partisan issues. If possible, you may even want to avoid explicit association with EA and GCR/XRisk (though see this suggesting this may not be a significant concern).
• For those in business and finance: The clean tech space is obviously huge. I don’t know what the opportunities look like there, but I trust you can figure it out. Also keep an eye out for opportunities to help design and implement certain climate policies, such as public investment in R&D and cap-and-trade schemes, especially if you have an affinity for social science and ethics. And check out Giving Green.
• For natural scientists: Focus your research portfolio on extreme climate change scenarios, including those involving solar geoengineering, to inform analysis of GCR/XRisk. I would also look into ways to have a more direct impact, such as advocacy (as in e.g. Katharine Hayhoe or Michael Mann), or even civil disobedience. Indeed, to the extent that you’re up for it, I would probably make these more direct activities be your primary focus. There are limits to how much additional natural science informs and influences decision-making.
• For social scientists: Two options. (1) Study real-world strategy for advancing emissions reduction. This post has plenty of starting points: urban politics, fission misperception, civil disobedience, etc. But what actually works? What are the high-leverage opportunities? Be sure to do this in dialog with those who may actually be implementing the strategies. (2) Study the potential for climate change to cause global/existential catastrophe—the collapse of civilization etc. The debate about climate change as a GCR/XRisk largely comes down to how well humanity would cope.
• For interdisciplinary people who can do anything: Look across all of the above and tease out the most high-value opportunities you can find. I suspect this may involve some social science on real-world strategy informed by a careful read of some engineering details, then cultivation of business allies, followed by some public advocacy and engagement in electoral politics. Good luck!
• Bonus idea—for people who are good at human development and emergency management/preparedness: This idea is a bit different. It’s focused on climate change adaptation, especially for more extreme scenarios. Climate change could induce some radical human challenges, such as migration at a scale that dwarfs anything currently happening. At that scale, it may be a political challenge as much as it is an operational challenge. People who are good at that sort of thing may do well to work on early-stage preparedness for this sort of scenario, perhaps by piggybacking on more mainstream adaptation initiatives.

Careers on other topics for people with backgrounds in climate change

A lot of work on climate change can be excellent training for work on other topics. OK, sure, your intimate knowledge of the thermodynamics of the Hadley cell may not specifically translate, but many of the general skills and capabilities will. Indeed, a case can be made for some people starting out in climate change specifically to prepare them for work on other topics.

I am a case in point. I did a Ph.D. on climate change in part because climate change is important, but also in part because it was a great learning opportunity. I wanted to do interdisciplinary research; climate change had (and still has) unusually robust interdisciplinary research. It was a great fit.

There are lots of possibilities. Here are some specific ideas:

• Policy and politics: It’s common for people in policy and politics to shift the topics they focus on, at least for people in certain types of positions. Because climate change is so multifaceted, it provides natural starting points for engagement on a variety of other topics. For careers in electoral politics, it may work well to start with an emphasis on climate change while having an eye toward potentially shifting topics later. For example, future technologies (AI, biotech, etc.) are not yet significant political issues, but perhaps they will be sometime later.
• Cross-cutting analysis of GCR/XRisk: If you’re already studying the human impacts of climate change, especially the potential for climate change to threaten human civilization, this readily translates to research on other GCRs/XRisks. Overall, the resilience of human civilization to various catastrophes is one of the largest and most important points of uncertainty in GCR/XRisk, of central relevance for how to allocate resources and evaluate tradeoffs across the risks. Expertise in climate change impacts is as good of a background for this as any.
• AI governance: AI and climate change have some important similarities. Both are driven by profitable activities of some of the largest corporations in the world. Both involve products used by the general public as part of their daily routines, and by businesses and governments and other institutions. AI governance has seen a lot of progress recently, but it remains a relatively early-stage field, especially in comparison to climate governance. One can do a lot by applying insights and experience from climate governance to AI governance. Indeed, this has been a major focus of my own work (1, 2, 3, 4, 5, 6, 7, 8, 9), which also provides some starting points for anyone interested. See also AI corporate governance.
• Nuclear winter: For natural scientists studying climate change, your research may readily apply to nuclear winter, which is a different type of climate change. Other climate scientists are already doing this. Nuclear winter is important but it gets much less research attention than “regular” climate change.

Philanthropy

Climate change vs. other causes

In the section “Climate change warrants massive investment—but not necessarily ours”, I explained that “because emissions reduction is so difficult, we may often have better opportunities on other GCRs/XRisks”. This reasoning suggests that philanthropic dollars may be better spent on other GCRs/XRisks. However, this is at best a tentative conclusion. The GCRs/XRisks are all poorly quantified, making the comparison difficult. I can see a case for climate change philanthropy, especially if one has unusually high-value ideas and opportunities.

Specific climate change opportunities

I’ve looked through analysis from Giving Green and Founders Pledge (see also this). I’m not seeing any glaring concerns. Honestly, it looks like good analysis. Giving Green in particular has a lot of great content. My own thinking points in a lot of the same directions, the main difference being that they go into a lot of important detail that’s beyond the scope of my own expertise. For example, Giving Green’s A business case for beyond net zero is pretty much exactly how I would look at it, except they’ve done it with more substance than I could. I could be wrong, but it looks like they’re doing good work.

The most I could say to the teams at Giving Green and Founders Pledge would be to maybe mine this post for any further ideas,^[16] but otherwise keep up the good work.

Acknowledgments

Thanks to Matthijs Maas, Andrew Morton, Jack Davies, and Dakota Norris for helpful feedback on an earlier draft. Any remaining errors are mine alone.

[1]    Universe, multiverse, etc.

[2]    GCR and XRisk are sometimes defined to be different, but I’m using them together to avoid lengthy definitional matters. Think of “GCR/XRisk” as being “the type of extreme global risk that you care about if you care about extreme global risk”.

[3]    There can be a role for extreme adaptation to reduce GCR/XRisk in the event that climate change becomes especially severe. Preparing for this is a more specialized activity—see the section “Careers in climate change”, specifically the “Bonus idea—for people who are good at human development and emergency management/preparedness”.

[4]    Other definitions of global/existential catastrophe can be substituted without loss of generality.

[5]    This point is developed at length in the book How to Avoid a Climate Disaster by Bill Gates (yes, that Bill Gates). In general, one should be skeptical of books by famous people, especially when they’re outside the person’s primary expertise. However, this book actually seems to be quite good, especially for laying out the problem of getting to zero emissions. It got a favorable review from a top expert here. Gates’s story may also be of note because he became interested in climate change due to his work on global poverty.

[6]    I am borrowing this point from p.88-89 of the book Climate Shock by environmental economists Gernot Wagner and Martin Weitzman. The book is an economic perspective on catastrophic climate change. I have my qualms with some of the economics, but the book has a lot of valuable perspective and is, to its credit, much more pluralistic than a lot of economics research. Wagner also has a great Twitter account.

[7]    Adams became vegan for health reasons, though his case still shows the synergy between individual and collective action on GHG emissions. To a large extent, it doesn’t really matter that he did this for health and not for climate change. The climate doesn’t care why you reduce GHG emissions.

[8]    See research literature (1, 2, 3, 4, 5, 6, 7), EA Forum posts (1, 2, 3, 4, 5, 6, 7, 8).

[9]  Here is an example of a reference covering all four of these individual actions, finding having children to be the most important, followed by the others. Here is a review paper surveying the space of individual actions but not including having children.

[10]  Though I have not seen any literature on this.

[11]  (Resisting the temptation to share vegan recipes here...)

[12]  Take the orange pill. Do it. DO IT!!! (I’m only half-joking. Maybe less than half.)

[13]  On transportation policy, see e.g. work by Greg Shill, Kimberly Nicholas, and David Zipper.

[14]  Those cities are all in Europe, but there is a lot of great urban innovation elsewhere. For example, the world’s best bus network is in Curitiba, Brazil; the best ciclovía/open streets program is in Bogotá; the best car-free street network in North America is Montreal; great design can be found in many Asian cities such as Taipei and Tokyo; the largest car-free place in the world is the old Medina of Fez, Morocco; in the US, there’s a top-quality new development in Tempe, Arizona. Finally, we have the intersection between Great Power politics, artificial intelligence, intrusive surveillance states, climate change, and urban affairs: China using surveillance cameras and AI to help with basic urban issues, such as making sure the electric bicycles are parked in the right places. Actually, privacy issues aside, it does seem helpful. In much of the West, surveillance cameras are also used for traffic enforcement with much success (e.g., in Sweden).

[15]  For example, by only using solar geoengineering on a limited, gradual, temporary basis to avoid some of the worst effects of global warming (1).

[16]  Reform the US transportation engineering profession? Support politicians advancing transformative transportation change in cities? These seem like plausible opportunities but I haven't costed them out at all.