The Latest Science on the Global Climate Crisis

Published Aug 16, 2022

Economist Dr. Rachel Cleetus discusses how global warming is impacting countries around the world and informing global action

In this episode

Colleen and Rachel discuss:

  • the interwoven role of science in international climate negotiations
  • the need for global action on climate change
  • how the climate crisis is affecting those countries who have contributed the least to heat-trapping emissions
Timing and cues

Opener (0:00-0:28)
Intro (0:28-5:37)
Interview part 1 (5:37-13:39)
Break (13:39-14:27)
Interview part 2 (14:27-28:25)
Outro (28:25-29:00)


Editing: Colleen MacDonald
Additional editing and music: Brian Middleton
Research and writing: Pamela Worth and Cana Tagawa
Executive producer: Rich Hayes
Host: Colleen MacDonald

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Full transcript

Colleen: Welcome to Got Science? I’m your host, Colleen MacDonald. Before I start the show as usual, I have the podcast equivalent of a breaking news update.

Spoiler: For the first time in a while, it’s really good news!

For years, it’s been darn near impossible to get meaningful legislation passed to address climate change and its harms. And we need it. At stake is no less than a livable future—and, increasingly, a livable planet.

If we look at just the past few months in the US alone, we’ve had record-breaking extreme heat and drought, even here in New England. There was flooding in Eastern Kentucky that killed almost 40 people, and wildfires raging from Alaska to Arizona.

But I said there was good news, and there is. The Inflation Reduction Act, which just passed the US Senate and House, and will be signed into law by President Biden soon, is a big big deal. It’s the biggest investment in combatting climate change in US history. The Inflation Reduction Act could help reduce heat-trapping emissions by roughly 40 percent by 2030.

Its power lies in its sheer scope—in the many ways it accelerates the transition to clean energy across our economy, from increasing the amount of renewable energy we generate, to expanding access to it, to jobs and manufacturing… plus beginning to reckon with how best to cope with present and pending climate impacts.

This law will help put cleaner vehicles on our roads, reduce industrial pollution, and make energy use in homes and buildings cleaner and more energy-efficient. It will save people money on gas and electricity bills, create hundreds of thousands of U.S. manufacturing jobs, and enable farmers to be part of the climate solution through funding sustainable agriculture initiatives.

The Inflation Reduction Act will encourage US states and other countries to enact similar legislation and policies. And all of this gives us a fighting chance of avoiding devastating levels of warming.

So even though it feels like it took way too much work to convince our representatives that they should act on a crisis… even though there were disappointing and dangerous oil and gas giveaways written into the bill for political reasons… even though it’s long overdue and we still need so much more… my colleagues and I, and many others working in this space, are relieved… to say the least.

My colleague, policy director Dr. Rachel Cleetus, sums this up in a recent blog post, saying, quote, “The overall bill is a big win for climate, jobs, and justice. And it gives us a firm basis to fight for more in the months and years to come,” end quote.

But just because this bill will be law soon… we are not done.

The bill doesn’t go far enough to address the ways in which oil and gas companies are burdening low-income communities and communities of color with increased exposure to pollution. We’re still giving away too much to Big Oil, at the expense of poor and BIPOC communities. In the process of getting this legislation passed, a lot of good and helpful measures were left out. So, it’s our job to keep fighting for these, and for an equitable transition to clean energy that will benefit everyone.

It’s also our job to recognize when we’ve made a difference in this long struggle for a livable future. So we’re taking a beat to celebrate. For all of us who care about climate change, who have been supporting UCS, or doing your own work for the planet—congratulations. We hope this bill will end up the first of many that set us on a much better path to a sustainable future.

Now let’s get to today’s episode.

Big wins like the Inflation Reduction Act and the investment it makes in fighting climate change—well, that they haven’t come as often as they should.

And because of that, working on climate issues can be draining. I feel a kinship to all of you listeners out there who take time out of your day to learn about progress, or lack of progress, on this global crisis. I know it can be hard to stay tuned into this fight. So I hope you’re celebrating today. And I hope you always know that you’re not alone in the care and concern you have for our planet and for people.

Here to remind of this fact is my colleague, economist and policy director Dr. Rachel Cleetus. She joined me to talk about the United Nations Intergovernmental Panel on Climate Change, what it is, and what its members work on. While we discuss the grim facts of climate change, including its disproportionate effects on the most vulnerable and least responsible for the climate crisis we face today, learning more about this body of global actors gave me hope for a brighter future. Whether on the local, national, or global level, we all have the opportunity and responsibility to build the healthy and equitable world we want to see. Learning from Rachel reminded me of the power we have when we work together… so stay tuned if you could use that reminder yourself.

Colleen: Rachel, welcome back to the podcast.

Rachel: It's great to be here, Colleen.

Colleen: You've been involved in international climate meetings for a number of years now. And I know we've talked about those meetings in the past with a focus on what's happening right here, in the U.S., but today I'd like to talk to you about what's going on in the international arena. And I'm kind of curious, what was the first international climate negotiation meeting that you attended?

Rachel: Actually, the first one I attended was back in 2009 and it was just before the Copenhagen climate talks in 2009. There was a pre-meeting before that in Spain that I attended, in Barcelona, and it was my first exposure to what that space looks like. Fascinating. And I think the most interesting part of it is you really get to hear directly from countries all over the world who are being affected by the climate crisis. And it was very moving to hear directly about these impacts but also to see a space in which cooperation diplomacy can provide a path to a better future.

Colleen: So, what would you say in the intervening years, as you've attended more of these meetings, I'm curious to know how things have changed throughout the years?

Rachel: Well, you know, you get to see both extremes of what international global diplomacy looks like on an issue like climate. On one hand, it is, as I mentioned, the one space where every country has a voice. It doesn't matter how small you are, you have a voice as much as a big rich country like the United States. But it's also a reminder that global power dynamics and geopolitics affect every space and they do also affect the negotiations on climate change.

There is a lot of power and privilege that's exercised by richer countries like the United States, like the European countries. And over time, this has created a dynamic where some of the equity aspects of the global climate crisis have not been adequately reflected in the outcomes in these negotiations.

And so, we continue to fall short of climate goals because countries are not doing enough, both to cut emissions as well as to respond to the needs of those who are on the front lines of this crisis around the world.

Colleen: Have you seen progress with regard to equity?

Rachel: You know, unfortunately, the climate crisis is just continuing to accelerate in ways that are truly terrifying and also imposing such a huge human toll around the world. And our policies just have not caught up with what's necessary. So, on one hand, I think the problem is more clearly understood. The science has played a very important role in helping bring home the message, both that the crisis is here and that, if we fail to make sharp cuts in our heat-trapping emissions, it will rapidly get worse.

And that's been very important. The scientific bodies like the IPCC, the Intergovernmental Panel on Climate Change, have played a very important role in bringing the science to policy spaces like the UNFCCC, The United Nations Framework Convention on Climate Change, through which international climate negotiations happen. But that science has too often been ignored or sidelined when it comes to decisions that policymakers reach.

And so, unfortunately, I would say that the inequities of the climate crisis have actually gotten worse over time, despite the science being crystal clear for decades now.

Colleen: Rachel you recently visited Ethiopia was that a family visit or was it work-related?

Rachel: Yeah, actually, my daughter's from Ethiopia. And so, we go back, we try to go back every couple of years. And unfortunately, with COVID, it's been a little while. So yeah, it was amazing. We were able to go back. It was a quick trip but so good to be there.

But, you know, parts of Ethiopia, as well as Sudan, Somalia are really grappling with a terrible food crisis right now. And it is intersecting with everything else, right, this global energy crisis. There's been a lot of emphasis on Europe and all the pain Europe is feeling. But believe me, it's poor people who are really hurting from the rising energy prices. It's a global market, right? So, everything that we're seeing at the pump, here in the U.S. and Europe, it's even more acute in places where people are a lot poorer.

And so, you see...I mean, it's a collision of these things. And the climate aspect of it, in terms of this food crisis that Eastern Africa is experiencing, is very clear. So, it's not gonna make the headlines in the U.S. but there's millions of people right now who are in a very tough spot.

Colleen: So, let's talk for a minute about the IPCC, The Intergovernmental Panel on Climate Change, and what its actual role is in the climate meetings. How do the two of those weave together?

Rachel: Yeah. So, the IPCC was formed way back in 1988. It is a United Nations body that helps assess the latest science around climate change and it is a body that's composed of scientists from around the world who are doing this work in large part on their own time and as volunteers to this global effort and are really trying to advance scientific understanding for policy makers to then make decisions.

The IPCC is not a policy body, it is very careful not to make policy-prescriptive statements, but it does policy-relevant science and brings it to international fora like the climate negotiations. And when the Paris Agreement was reached, there was a very intentional ask to the IPCC to provide specific information about the goals in the Paris Agreement, the 1.5 C goal, for example, that countries committed to saying that they would do their utmost to ensure that we would not breach that threshold. And the IPCC was asked to assess what it would take to meet that goal and what would be the kinds of climate impacts that the world would face if we exceeded that goal.

And they wrote a report, the IPCC 1.5 C report it's called colloquially, that was entirely at the request of nation states. Very very useful information and also very sobering information, showing us that climate impact's rapidly worsen as we reach 1.5 C and beyond.

The IPCC has also played a very important role in creating capacity around the world for scientists to engage in this process. And one aspect that's really important to recognize is that scientists from developing countries have been historically seriously underrepresented in these kinds of bodies. And that's something that the IPCC is working to change actively, over time, in terms of diversifying the authors for lead chapters, creating venues for scientists to meet in countries so that they're not always having to travel from developing countries. And also encouraging more scientific research in the context of impacts that developing countries face.

The IPCC is meant to look at the latest and best available science. It doesn't generate its own science so much as assess the latest scientific evidence that's out there. And the reality is we have a lot of scientists in richer nations who are doing science in the context of, say, Europe and the United States and not enough happening in the context of places like the continent of Africa or in Asia and South America. And the IPCC is working actively to change that dynamic so that, over time, we have better representation, more inclusive representation, from around the world.

Colleen: The heat waves across the U.S. and Europe this summer have garnered a lot of headlines and have certainly raised concerns about what summers will be like in the future. What were some of the findings of the most recent IPCC reports that people may be less familiar with?

Rachel: Yeah, one of the striking aspects of the IPCC Working Group II report, which is focused on climate impacts and adaptation, is its description of impacts that are already here and now. And we are, unfortunately, seeing that in our lived experience. you mentioned the heat waves in Europe and the U.S. You know, there was an extended heat wave in Pakistan and India earlier this year. There have been heat waves in China that's been flooding in Asia. There's been a number of extreme drought and heat-related events in the horn of Africa that are triggering now a significant famine and food crisis there, in Eastern Africa. We've had catastrophic flooding in South Africa.

So, what we're seeing is, all around the world, wherever we look, the reality of the climate crisis is so crystal clear. And Secretary General Antonio Guterres, UN Secretary General Antonio Guterres, called that report, the IPCC Working Group II report, he called the report "an atlas of human suffering." And that phrase just captures very poignantly the reality of what these climate impacts mean to people around the world.

One thing that we have to recognize is that these impacts are inevitably falling in a way that's much more harsh for people who have the fewest resources to cope with these kinds of extreme events. And, in many cases, these are often the very same people who have contributed the least to the problem because their carbon emissions are very very low. So, in a nutshell, that is the inequity of the climate crisis. Not only is it unfolding everywhere and affecting us all but it is falling disproportionately on those who've got the least to do with the problem and have the least resources to cope.

Colleen: Can you take us through the most recent IPCC reports that came out?

Rachel: Sure. So, the IPCC has been producing, what's called, "assessment reports" that assess the latest climate science since the early 1990s. And they are currently in their sixth assessment cycle. And starting last year, they started releasing the reports in this cycle. There are three major reports, the first one is "The Physical Science Basis For Climate Change," that report was released last summer. And then this year they released two subsequent reports, one on impacts and vulnerability, that's called Working Group II of the IPCC. And then Working Group III, which is focused on mitigation or solutions to cut emissions, essentially. And now the IPCC will be releasing, early next year, what's called "A Synthesis Report" which takes all three of the reports and summarizes it together.

Now, the way the IPCC works, as I mentioned, it's not a policy-prescriptive body but it does produce policy-relevant science. And they produce a long technical report and then country negotiators get together for an intense negotiating session where a summary for policy makers is negotiated. And that summary for policy makers, I should emphasize, scientists still hold a pen, nothing gets into that summary that's not been run by scientists and is scientifically-accurate but countries negotiating, policymakers negotiating for what makes it into that summary and deciding what to emphasize.

And UCS has had the privilege of participating in those closed-door sessions of negotiations. And I had the opportunity, earlier this year, to be part of those negotiating sessions for the Working Group II and Working Group III reports. And it is a fascinating process because you really get to understand how countries recognize both the reality of climate change but also are constantly trying to figure out what, from their perspective, should be emphasized or not emphasized in that summary for policymakers.

And one really poignant piece I just want to mention is that the war in Ukraine broke out during the negotiations for the summary for policy makers for the Working Group II report. And it was a virtual session with people joining from around the world, including NGO observers like UCS, and the Ukrainian delegation was just so brave so committed to being in that space but they had to finally leave because they said that, "We were being bombarded." The invasion was underway and they, ultimately, had to leave the negotiating sessions.

And then there was a very dramatic moment in the final plenary session where the Russian delegate apologized for his country's unjust invasion of Ukraine. These are all closed-door settings not open to the media but there were people in the room who spoke to the media about it and there were a number of news stories on it.

And it is just one of those moments where you recognize that, "Yes, this is about countries, it's about science, but it's about human beings." It's about people who are trying to do science under extraordinary conditions.

Colleen: Wow, that's a powerful story.

Rachel: That was a very moving and stunning moment. And I think all of us who were there were just...yeah, it was one of those moments that transcends ordinary geopolitics.

I would say, the other piece which is important to recognize is that it's very important for climate-vulnerable developing countries for the science to reflect the disproportionate impacts that their countries are facing. And one of the frames in which this issue is talked about is loss and damage. And loss and damage is, essentially, the recognition that some climate impacts are so extreme that you can't adapt to them through ordinary means. And I'm talking about things like loss of land because of sea-level rise. There isn't really an ordinary adaptation measure beyond, you know, just having to leave.

So, in the IPCC negotiations, there is always a line that has to be met, which is that it is not going to be a policy-prescriptive report. And yet, at the same time, the science is clear that loss and damage is a reality for climate-vulnerable developing countries. But because the phrase "loss and damage" is the one that's used within the climate negotiations and because it is such a fraught issue in the climate negotiations because richer countries have blocked progress on loss and damage, in the IPCC venue, it was decided to use a different phrase "losses and damages" rather than "loss and damage" to avoid frictions over what would be considered policy-relevant climate negotiation aspects.

Colleen: As we talk about climate vulnerable nations, who have contributed the least to heat-trapping emissions I think it would make sense to run through the top countries that are contributing the lion's share of global-warming emissions?

Rachel: So, one really important thing to recognize is that the climate change that we're experiencing right now is a result of accumulating heat-trapping emissions in the atmosphere. So, it's the cumulative emissions from countries that really matter. And although, on an annual basis, China has now overtaken the U.S. in terms of being the largest emitter, on a cumulative basis, the United States is by far the largest emitter of emissions to date. It's responsible for about a quarter of global heat-trapping emissions on a cumulative basis since the industrial revolution started.

And the next country behind it on a cumulative basis, China, contributes approximately 14%. So, you can see that the U.S. is really an outsized contributor to heat-trapping emissions.

Then we have countries like Russia, Germany, UK, Japan on a cumulative basis that are in the top five or six nations. And what this shows us, therefore, is that we, in the United States, are uniquely responsible for these climate impacts and we have an amazing opportunity to be part of the solution. Because the United States is also a place where we have so many opportunities to expand renewable energy, energy efficiency, shift to clean our transportation, decarbonize across our economy, and we need to live up to that responsibility. It's a smart thing to do for a variety of reasons, for economics, public health, and it will make sure that we make a fair contribution to global climate action.

Colleen: So, I'd like to acknowledge some of the countries that are facing the most severe impacts right now. I mean, I know you can't name them all but can you give us a sense of who is being unjustly impacted by climate change?

Rachel: So, the IPCC report points out that more than 40% of the world's population today lives in areas that are highly vulnerable to climate change. So, this is clearly a very large problem for many many people around the world. And about half of the world's population is currently experiencing water scarcity for at least some part of the year. And this is related to climate change.

Now, the folks who are the most vulnerable include people who are living in communities in low-lying areas that are vulnerable to sea-level rise and are losing land. Think about small island nations, countries like Bangladesh. The reality is, around the world, a lot of our population is concentrated in coastal areas, including right here in the United States. And those are some of the populations that are most at risk as sea-level rise accelerates.

The other piece that's putting people at risk is this water-scarcity challenge, glacial loss, drought, the uneven kinds of rainfall that the world is experiencing either too much or too little coming at the wrong times is creating a real water-scarcity crisis for many many people. Including in the Asian subcontinent, in places like in India, in Pakistan, and also in South America where the glaciers in the Andes are also increasingly disappearing and creating a water-crisis challenge there too.

So, those are some of the places in which people are very vulnerable but the reality is there are so many of these climate impacts. There's drought that's triggering a food crisis, as I mentioned, in the horn of Africa right now. That is a multi-year drought and millions of people are at risk, many of them very young children who are at risk of losing their lives. So, an acute climate-related hazard, in that case.

Colleen: Well, Rachel, I really appreciate this global perspective because so much of what we talk about on the podcast is really focused on the U.S. and what's happening in this country. And it's so important to hear what's going on in other parts of the world. This may seem a little morbid but what impacts scare you the most?

Rachel: I think the impacts that scare me the most are, what are called, slow-onset disasters. So, you know, the things that make the news often are the extreme weather events. You know, you have a hurricane or you have an extreme heat wave and it makes the news headlines. But what's happening under the surface is climate change is causing some profound irreversible changes in ecosystems that human beings rely on.

I mentioned the loss of glaciers and how that's affecting water availability, and water is a matter of survival for people. So, that's the kind of thing that doesn't make the headlines but is going to be one of the most serious challenges that people face. And as a result of these kinds of extreme risks that will accumulate, climate change is going to trigger mass displacement of people from some of the highest-risk areas. Whether it's coastal areas that are losing land, places where water or food scarcity becomes a challenge, and places where these climate risks are going to intersect and are intersecting with other challenges, economic challenges and geopolitical challenges.

And that scares me because, when you think about a lot of people having to leave because they're no longer safe in the place they call home, the question is, "Where will they go and how will they be received when they get there?" Because the reality is that right now migrants, refugees are not treated very well around the world. There is a lot of racism and xenophobia that's wrapped up in how people are treated. And we need to do a lot better as a global community, and especially richer countries have an obligation to have frameworks in place where human rights are respected, where the dire conditions that are being triggered by our carbon emissions are taken responsibility for.

Colleen: Well, Rachel, thank you so much for joining me on the podcast. And I really do appreciate this global perspective because we really don't hear that enough. And I thank you for your continued fight for a healthy planet and a just planet. Thank you.

Rachel: Thank you so much for having me, Colleen.

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