Taking stock of our climate past, present, and future

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New Year's Eve is my favorite holiday. It's a time to celebrate, reflect, and look forward to what's next. Setting goals, drinking champagne-what's not to like?

Before you say anything, I do know that it is, in fact, nearly April. But this week has the distinct feeling of a sort of climate change New Year's to me. Not only is it the spring equinox this week, which is celebrated as the new year in some cultures (Happy Nowruz!), but we also saw a big UN climate report drop on Monday, which has me in a very contemplative mood.

The report comes from the UN Intergovernmental Panel on Climate Change (IPCC), a group of scientists that releases reports about the state of climate change research.

The IPCC works in seven-year cycles, give or take. Each cycle, the group looks at all the published literature on climate change and puts together a handful of reports on different topics, leading up to a synthesis report that sums it all up. This week's release was one of those synthesis reports. It follows one from 2014, and we should see another one around 2030.

Because these reports are a sort of summary of existing research, I've been thinking about this moment as a time to reflect. So for the newsletter this week, I thought we could get in the new year's spirit and take a look at where we've come from, where we are, and where we're going on climate change.

Climate past: 2014

Let's start in 2014. The concentration of carbon dioxide in the atmosphere was just under 400 parts per million. The song Happy" by Pharrell Williams was driving me slowly insane. And in November, the IPCC released its fifth synthesis report.

Some bits of the 2014 IPCC synthesis report feel familiar. Its authors clearly laid out the case that human activity was causing climate change, adaptation wasn't going to cut it, and the world would need to take action to limit greenhouse-gas emissions. I saw all those same lines in this year's report.

But there are also striking differences.

First, we were in a different place politically. World leaders hadn't yet signed the Paris agreement, the landmark treaty that set a goal to limit global warming to 2 C (3.6 F) above preindustrial levels, with a target of 1.5 C (2.7 F). The 2014 assessment report laid the groundwork for that agreement.

Technology has also changed dramatically. The 2014 report put renewable energy on the table as a potential solution to replace fossil fuels and slow climate change. But renewables had yet to make a significant difference in emissions, partially because they were still so expensive (per watt, solar power was about five times more expensive than it is today!).

It's crunch time, now."

Detlef Van Vuuren

Looking back, it's frustrating just how clear the warnings were on climate change a decade ago. But it's also a little bit heartening to see just how far we've come with awareness, political momentum, and technology.

Climate present: 2023

Fast-forward nine years, or seven Taylor Swift albums. The year is 2023, carbon dioxide concentrations averaged 419 parts per million last year, and global temperatures are about 1.1 C (2 F) higher than they were before 1900. In March, the IPCC released its sixth synthesis report.

Climate change has broken into the public conversation, with both supercharged disasters and momentous climate action to talk about. A movie about climate change was nominated for a 2022 Oscar. Nearly half the voters in the last US presidential election said climate change was very important to their vote, and 93% of Europeans believe that climate change is a serious problem.

The US, the world's leader in total historical emissions, passed landmark climate legislation, the largest in history. But emissions are still ticking up, hitting a new record high in 2022.

The 2023 IPCC synthesis report is more dire than its 2014 predecessor. Higher risks from climate change are now projected to come at lower levels of global warming. And it's even more clear how crucial it is to act quickly.

I spoke with one of the authors of the IPCC report, climate scientist Detlef Van Vuuren. One clear difference between the fifth and sixth reports is the urgency of this moment: It's crunch time, now," he told me.

The good news is there are a lot of solutions available right now. It's possible for us to set ourselves up for success by 2030, when we could be well on our way to reaching our climate goals. The IPCC has handed out a climate to-do list that we need to get going on. For more on what's on that list, check out my story from Monday.

Climate future: 2030

By the time the next synthesis report comes out, around 2030, NASA may well have put humans on the moon again.

It will be clear by that time whether or not limiting global warming to 1.5 C is still on the table. Right now, we've got just under a decade left of emissions-as-usual before we've sailed past that goal.

Here's what the world may need to look like in 2030 if we're going to reach net-zero emissions by 2050 (which is what we'd need to do to hit the 1.5 C target), according to a few of the International Energy Agency's projections:

• Power generation from renewables needs to be over 20,000 terawatt-hours, 60% of the global total.
• Richer countries need to stop running coal-fired power plants without carbon capture.
• EVs need to make up 60% of vehicle sales.

That's a lot of transformation, but then again, energy analysts have consistently underestimated the contributions renewables would be making. So who knows what 2030 might bring?

I'm always cautiously optimistic going into each new year, and that's how I feel now too. The stakes are high, and there's plenty to be worried about on climate change. But I look around and see a lot of potential progress ahead.

Keeping up with climate

A city in Germany wants to store energy in aquifers underground. If the system works, it could help replace a coal power plant. (Bloomberg)

California could pass strict pollution rules for trucks. The regulations would jump-start electric trucking across the country. (Washington Post)

Here's why the grid is ready for fleets of electric trucks. (MIT Technology Review)

We need the right kind of climate optimism: the kind that spurs action. (Vox)

Climate change is the star of the new show Extrapolations. (LA Times) Some argue it doesn't do the topic justice, though. (Washington Post)

Tesla announced it would stop using rare-earth metals for magnets in its motors. Experts are skeptical. (IEEE Spectrum)

Going on an EV road trip has gotten easier in recent years, but there are still some speed bumps. (E&E News)

Heat pumps are commonplace in Japan and some other countries in Asia. Their success could be a blueprint for efficient heating and cooling in the rest of the world. (Canary Media)

Here's how a heat pump really works. (MIT Technology Review)

Tractors that run on cow manure could help farmers get around while cutting methane emissions. (Bloomberg)

Lithium prices are falling, making EVs that use the metal in their batteries cheaper. But rising demand could turn things back around soon. (New York Times)

New Mexico is putting up a fight against a proposed storage facility for nuclear waste in the state. (Associated Press)