This post is written for a friend who told me she felt overwhelmed by climate change. I told her that over the past few years I have become more optimistic about humanity’s odds against it. Here I explain why:
As recently as 2014, climate projections had 4 degrees celsius of warming by the end of the century. Just 8 years later, the median estimate of warming is ~2.6 degrees celsius. We cut expected warming almost in half!
What happened? [1]
Renewable energy got cheap fast
The price of renewable energy dropped in an almost unbelievable way: Solar energy declined by ~90% in 10 years. Wind declined in price by 70% in ten years. If what happened for solar panels happened for rent in Manhattan, that would mean a one bedroom apartment went from costing $2926 in 2012 to $380 in 2022 (instead of $3,810) (accounting for inflation). That would be pretty crazy! Price declines are impressive, but more relevant is how the price of renewables compares to the price of fossil fuels: in most places power from new renewables is now cheaper than new fossil fuels. Right now, fossil fuels still account for 79% of the world’s energy production, but renewables have only gotten cheaper than fossil fuels in the past few years. Renewable uptake is rising as people respond to these new incentives. Renewables are also hopeful because they point towards the possibility of a sustainable high energy future: one where developing countries can increase their energy use without it leading to global disaster.
Brief aside: Why did solar get so cheap?
For the briefest most superficial summary (Read way more here): In the 1970s, the energy crisis caused the US to invest a bunch in solar research and development. This basically fell off in the 80s, but they made some progress. This progress was taken up by Japan, which took the R&D further, found niche markets where expensive small-scale solar made sense, and started the first subsidies for people to actually install solar (so touching demand for the first time and doing “demand pull” not just “technology push”). In 1998, the German Green Party became one of the leading coalitions in the German parliament, and they passed a major climate bill that provided 200 BILLION in solar subsidies. This was the big demand pull (also having political parties that care about climate in power really matters!). China, partially because of the opportunity to sell to the German market, got into solar manufacturing and through entrepreneurs and the Chinese govt does a massive industry scale up which finally helped get costs down to basically where they are today.
Countries made major commitments
Alongside technology, bilateral and unilateral national commitments contributed to climate progress. The most famous, the Paris Agreement, ratified in 2015, required all signatories to set emissions reduction targets and also explicitly laid out the goal of reaching net zero / carbon neutrality. Many people were disappointed by Paris because the agreement was nonbinding. Many countries seem nowhere near meeting their goals, but nevertheless, Paris was significantly more ambitious than Kyoto, applying to more countries and more greenhouse gasses. It seems like Paris motivated more action than we would have gotten in the default world.
There have also been important unilateral steps: In 2020, the EU decided to raise the 2030 greenhouse gas emission reduction target to at least 55% compared to 1990. Also in 2020, China announced its aim to hit peak emissions before 2030 and for carbon neutrality by 2060. This seems particularly important because most future emissions will be from China.
Sub national efforts have also been impactful: In 2016, California passed the Greenhouse Gas Emission Reduction Act: “legislation requiring California to reduce its overall greenhouse gas emissions to 1990 levels by 2020 and 40% below 1990 levels by 2030” and the Renewable Energy Procurement Act in 2018, “Energy legislation requiring the state to procure 60% of all electricity from renewable sources by 2030 and 100% from carbon-free sources by 2045; double the energy efficiency of existing buildings; and allow greater electric utility investment in electric vehicle charging infrastructure.” Since California would be the country with the ~5th largest economy in the world if it were a country, these bills were as meaningful as if the UK or France had passed them.
And just this August, the US signed the most dramatic climate change bill of its history, allocating $369 BILLION ($500B if you add IIJA and CHIPS act) to climate priorities including clean energy and electric vehicle tax breaks, setting limits on methane leaks and increasing other fees for fossil fuel producers, funding domestic manufacturing of batteries and solar panels, and pollution reduction. I had given hope of Congress doing anything meaningful, and my brain was set to register it when they actually did. I appreciate the twitter hysteria over this that caught my attention.
Activism has raised the salience of climate change
Climate activism has been going strong for decades, for example, Greenpeace was founded in 1971. But more recent climate movements have garnered larger followings. The Sunrise Movement was founded in 2017 and Extinction Rebellion in 2018. It is hard to get an exact estimate of their impact, but for Sunrise they have over 400 hubs across the country, contacted over 6.5 million voters on behalf of political candidates they supported in their election campaigns, and have clearly influenced the positions of members of Congress on climate legislation, most notably AOC. Wider-spread activism puts pressure on governments and companies to act.
There are other reasons to be hopeful:
We have new directions for safer nuclear power which can either be transitional or used alongside renewables. One avenue is nuclear power that runs on nuclear waste, solving one of the major concerns with nuclear power.
Deep geothermal is also exciting. Basically, shoot water deep into the earth where it is very hot, it comes up as steam, use the steam to power turbines, charge batteries, etc. Geothermal is great because 1) you can do it anywhere on earth, just a matter of how deep you have to drill 2) the power generated by it is continuous, like nuclear and unlike solar or wind 3) it can use skills and infrastructure left over from fossil fuel production which means it will help with the economic transition -- to build geothermal you can drill and frack (but sans the fracking fluids that endanger water supplies or the oil/gas extraction and its related CO2 emissions), and coal power plants have big turbines that could be powered by steam from deep within the earth instead of steam from burning coal 4) there is so much more energy waiting to be used via geothermal than available in fossil fuels or nuclear. But geothermal is still nascent: we need better drilling equipment to be able to drill deeper and there are some permitting and subsidy things to work out (oil and gas are currently allowed to drill on federal land without going through a long review process because of a special exemption, geothermal doesn’t have this exemption yet).
There are exciting new avenues for carbon removal, since achieving net zero emissions likely means we’ll need to take carbon out of the air, not just avoid putting it there. There are also funders willing to fund carbon removal research and development. The flipside of this is that a lot more innovation will be needed. An International Energy Association report says that a third of emissions reductions will come from technologies that are not commercially available today.
The rapid deforestation in the Amazon looks likely to slow since right wing Jair Bolsonaro just lost the Brazilian presidential election to former leftist president Lula da Silva. The Amazon is a major carbon sink, so its fate is tied to that of the world. Lula reduced deforestation rates during his first two terms, they shot back up under Bolsonaro, and now Lula pledges to bring them down again.
More broadly, deforestation peaked in the 1980s and the Northern hemisphere has even started to reforest (meaning the rate of tree planting to tree removal has gone positive).
This nonprofit cleaned up 1/1000 of the great Pacific Garbage patch in 1 year. Maybe that doesn’t sound that hopeful (will it take them 1000 years to clean it up entirely???) but they have since developed a new version of their clean up tool which they believe is 10x as effective, so they expect to keep scaling up and to be able to clean faster. Their goal is “to reduce floating plastic by 90% by 2040” which is insane!
Natural disasters have increased in frequency, but deaths from them have actually fallen. This seems to be from better forecasting of disasters and increased ability to adapt. Natural disasters have increased 5x, and deaths have fallen by ⅔.
The Takeaway
There was a time in recent memory when we thought the end of the century would see 4+ degrees Celsius of warming. Now, we look on track for 2.4C. But we can -- and I believe will -- get this even lower (When I say “on track” I mean that we can peak at this level -- not plateau there. There is a lot we can do to quickly bring down temperatures after the peak via reforestation and carbon capture, instead of getting stuck at that temperature for decades or centuries.)
But we don’t seem on track to peak below 1.5C. This will have major consequences -- millions and maybe even billions will experience extreme heat or changed weather patterns that cause famine or natural disasters. This is tragic and unjust -- especially because this will disproportionately affect the world’s poorest, who contributed almost nothing to the problem and who do not have the resources to cope with the costs. We should have done more sooner, and even now, every bit of progress prevents additional suffering. This post was framed as optimistic so it has largely focused on the progress we’ve made. But that needs to be set alongside our failure to act sooner and more decisively to prevent needless suffering and death.
It is hard to hold in one's head both that we will achieve an inhabitable world past climate change, and that it will still cause serious and tragic disruptions for billions. We have so much progress to be proud of, and a bright future that scientists, policymakers, activists, and ordinary people, who care about their fellow humans and their earth, fought for.
The point of trying to show optimism about climate is not to ignore this suffering or to say our work is over, it’s to give us the hope and energy to continue that work. The world has accomplished a lot in the fight against climate change. There is a world to fight for. Your children, should you choose to have them, will see it.
[1] Another interpretation and/or factor here is that people have gotten better at interpreting what the forecasts are actually saying. For example, an emissions pathway called RCP 8.5 that predicted 4+ degrees of warming by 2100 received a lot of air time, often without the attached note that there was only a 2.5% chance of this pathway happening. Read more here.