The world is heating up. It’s not an ideological, political, or philosophical debate — it’s already a physical reality.
The extra heat is a direct result of our greenhouse gas emissions, especially carbon dioxide (CO2). While other gases like methane can also make a notable difference, CO2 is the elephant in the room. The level of carbon dioxide in the atmosphere is directly correlated with atmospheric temperatures, and the level has been increasing right after the Industrial Revolution started, due to our burning of fossil fuels. While the natural level of CO2 does fluctuate in time, this is unlike anything else in the past million years and is a direct result of human activity.
Herein lies the straightforward, but very difficult task. If we want to avoid or reduce the effects of climate change, we have to reduce our greenhouse gas emissions. The bulk comes from burning fossil fuels (and producing cement), but another significant part of it comes from our land use. Simply put, land use refers to cutting down forests and mismanaging carbon sinks like marshes.
To make matters even worse, our emissions have not yet peaked. The question should be whether our emissions are decreasing quickly enough, but our emissions are still growing. This is not the same for all regions in the world, and some areas are doing undeniable efforts. But globally, these efforts are simply insufficient.
Who’s responsible for climate change
While we’re all to blame for climate change to some extent, some are far more to blame than others. Looking at it at the country level, which countries are the most responsible for climate change?
A simple way to look at it is to see who’s producing the most greenhouse gases today.
There are two problems with that approach. The first is that it doesn’t take into consideration the population of countries. Emissions on a national level look quite different when you look at them per capita. China is the biggest emitter by far today, but per capita, it’s still faring better than the US or Canada, for example. At least for now.
The other problem is that this doesn’t account for historical emissions. Let’s take a look at China again: China’s been emitting a huge amount of greenhouse gases, but it’s been doing so for a relatively short time. Meanwhile, the US and Europe have been emitting for a much longer time. So if you look at the total cumulative emissions, the picture looks quite different.
Still, China’s emissions are surging and at current trends, they will surpass the cumulative emissions of the US in about a decade, which is not that long of a time, giving China a lot of responsibility for climate action (without reducing the responsibility of countries from Europe and North America).
This is more than just an ethical discussion. While measures that counteract climate change will likely save money in the long run, they will still require huge investments in the beginning, and money is still the elephant in the room when it comes to climate change. You could make a solid argument that developed countries have become wealthy by burning fossil fuels, and it’s unfair to ask less developed countries to make investments when they’re far less responsible for the problem. The problem of who should fund climate change investments internationally is one of the most pressing debates. China has been constantly dodging this responsibility, arguing that it is still a developing country and shouldn’t have to pay, despite its emissions.
Disagreements such as this one are why the UN launched the Conference of Parties conventions, where representatives from all around the world meet and attempt to find coordinated solutions to the world’s climate problem. The most remarkable achievement of the COP was the development of the Paris Agreement: a deal that is non-binding but was still ratified by virtually every country in the world. The Paris Agreement mandates that every country must play its role to keep climate change within 2 degrees Celsius of the pre-industrial average global temperature, with an ambitious goal of 1.5 degrees (we’re already over one degree). The deal mandates that every country take action based on its particularities; for instance, countries like Brazil or Indonesia, which host vast forested areas, will focus on maintaining and expanding these areas.
How are we progressing?
Much of our progress in tackling climate change comes from increased usage of renewable energy for electricity and heating. Advancements in technology have made renewables competitive and, in many instances, even cheaper than fossil fuels. As a result, renewable sources of energy (particularly wind and solar) have surged in the past decade.
Overall, however, fossil fuels still dominate our energy use, especially when you consider things like transportation and heating. Coal, gas, and oil make up over three-quarters of our total energy use.
Unsurprisingly, we are not on track to keep up with the Paris Agreement. In fact, our current policies would put us closer to a warming of 3 degrees, and even our pledges are slightly insufficient to reach that goal (nevermind that most of these pledges aren’t respected).
But there is a silver lining: we’re starting to see that countries’ economies and GDPs are decoupling from greenhouse gas emissions. This isn’t happening everywhere, and it’s not even happening in a majority of places, but in developed countries, it seems that burning fossil fuels is no longer strictly necessary for prosperity — which was the case until not that long ago. Basically, many countries are achieving economic growth while reducing their emissions.
If we could get as many countries as possible to this level, it would be a clear sign that climate action can be good for the economy. But getting other countries on board will be challenging.
The bottom line
The world is heating up. It’s a challenge unlike anything else mankind has faced, and it’s not something you can just put the brakes on. Even if we stopped emitting greenhouse gases today, the planet would still continue to heat up for some time. But the more we delay action, the worse it gets.
We’re not in a great spot. We weren’t in a great spot a few years ago, and a global pandemic and a major war haven’t helped the cause.
But there is hope yet. Thanks to technological and industrial improvements, renewable sources of energy are already competitive; we have what it takes to transition away from a climate disaster with today’s technology. There’s more information than ever on climate change, both academic and public information. Political arrangements, while far from ideal, have set some rough guidelines on how to limit climate heating. It’s a two-step-forward one-step-back kind of dance, but there is progress. Whether or not that progress is sufficient, though, is a different story.
The window of opportunity is shutting fast. The 2 degrees figure isn’t chosen arbitrarily — it’s a tipping point after which there will be permanent and irreversible damage, we won’t be able to go back to the way things were even if we achieve zero emissions. So we need immediate action now. The Climate crisis calls for rapid transformation of societies, and time is running out. If we want to act, we’d better act fast.
Andrei's background is in geophysics, and he's been fascinated by it ever since he was a child. Feeling that there is a gap between scientists and the general audience, he started ZME Science -- and the results are what you see today.