For all less encouraging news on climate change — rapid sea level rise risethe land transforms itself, serious trouble in production under the glaciers of Antarctica — we had a lot of hope. For example, renewable energy prices are falling and we are moving forward cleaner, electrified future faster than you might realize.
That change is evident in an almost subliminal dose paper published today in the magazine Nature: Modeling by an international team of scientists shows that if countries uphold their recent climate commitments, including those made at COP26, humanity can move on warming below 2 degrees Celsius above pre-industrial levels, the goal outlined in the Paris Agreement. It’s not below the 1.5-degree threshold we really want (the deal’s more optimistic target), but it’s far from extreme warming of 3, 4 or even 5 degrees, like some expected scenarios before agreement. And that will only happen if countries make good on their promises to rapidly decarbonize their economies – which is not guaranteed.
“The very high emission trajectories that people talk about today are no longer possible,” said Christophe McGlade, head of energy supply at the International Energy Agency and co-author of the new paper. such exam. “That’s good news because it shows how much progress the world has made in terms of policy and technology over the past few years.”
To achieve this rosier scenario of warming below 2 degrees, McGlade and his colleagues scrutinized the climate commitments nearly 200 countries made between the Paris Agreements, which are signed in 2015and the end of COP26 Conference last November. This is called a “net-zero” commit. For example, the United States has committed to going zero by 2050, which means by that time it will put as much of it into the atmosphere as possible. this is a pretty sticky concept, in which a country can continue to emit greenhouse gases as long as it also sequesters them with carbon-removal technology. They exist, but not anywhere near the scale required to create a dent in the carbon concentration in the atmosphere. Countries can (and should) also support ecosystems Natural sequestration of carbon in plantsthus offsetting emissions.
The researchers used all of those pledges to estimate future global emissions, then plugged it into a climate model that calculates a temperature increase of less than 2 degrees by 2100. ( For reference, we were about 1.2 degrees above pre-industrial levels.) “This suggests that if governments get what they have said they want to achieve under the terms of equal commitments. no, this will be the first time we’ve limited warming to below 2 degrees Celsius,” said McGlade. “There was never enough policy commitment, or enough policy momentum, until COP26 that would limit warming to below 2 degrees.”
Beyond that political movement, several trends have converged to make this progress possible. First, the cost of solar and wind power, as well as lithium-ion batteries to store electricity, increased by 85% between 2010 and 2019, according to The most recent report of the United Nations Intergovernmental Panel on Climate Change. “It’s really, really impressive, and one of the main reasons we actually got this result in the paper,” says McGlade. “In many cases, it is cheaper to deploy a new wind farm or a new solar farm than it is to deploy a new coal-fired power plant. That is the case in so many parts of the world today.”
