CU Boulder economist Alessandro Peri makes the case that empowering the young can meaningfully affect climate policy and climate outcomes

The consensus opinion in previous research—that future generations are the major beneficiaries of proactive climate policies—tends to emphasize the importance of intergenerational altruism. However, that perspective largely ignores the idea that selfish incentives of current young and old generations can be an important driver to undertake climate policy, says Alessandro Peri, assistant professor in the University of Colorado Boulder Department of Economics.

Recent studies indicate that peak global warming occurs within a decade of emissions. Thus, current climate policy could benefit young generations later in their lifetimes, says Peri, a macroeconomist whose research focus includes computational and environmental economics.

Meanwhile, climate policy may benefit the current old generations by reducing the damages associated with climate change and therefore increasing the value of their assets.

In the paper, recently published in the Journal of the Association of Environmental and Resource Economists, Peri and his two co-authors advanced what they say is the first study to examine the direction and magnitude of the selfish incentives of young and old to undertake climate policy.

In the economic model Peri and his co-authors developed, the younger generation (ranging from infants to those aged 35) and the older generation are both part of solutions addressing the climate crisis. The older generation tends to control most of the world’s physical assets, such as factories, he notes.

“What we found after we analyzed, theoretically and quantitively, this question of selfish incentives for climate policy is that incentives of the younger generation can be an important driver for climate policy to address the challenge of global warming,” says Peri.

Abatement measures related to reduced carbon emissions can affect the asset owners’ wealth and, accordingly, the old generation’s selfish incentives to support or oppose climate policy, but the effect is quantitatively small. Hence, Peri says, the exhortation in the title: “Empower the Young!”

When climate policy is a win-win

To explore the selfish incentives for climate policy, the model Peri and his co-authors developed uses a two-generation overlapping generations model, rather than the more common infinitely lived agent model. Peri says the two-generation structure permits a clear distinction between the two types of self-interest: the younger generation’s concern for its future consumption and the older generation’s desire to protect its wealth.

For the incentives of the current young and old generations to undertake climate policy to be aligned (a win-win situation), climate policy must increase the value of the assets owned by the old generations.

“Think about it like if you own a house in front of a lake,” Peri explains. “You don't really like the lake, but someone else decides to clean the lake. Well, the value of your house close to the lake is going to increase; you’re going to benefit indirectly from the cleaning of the environment on your wealth. The (increase) of this price allows the older generations to engage in climate policy and be happy about climate policy.”

For this to happen, Peri and his co-authors created an economic model that uses endogenous asset prices, relaxing the assumption of fixed asset price adopted by most models in the climate literature.

As wealth is transferred from the older generation to the younger one, for the asset price to increase it has to be the case that current young generations want to save more.

“They (the young) are willing to consume a little bit less today and save for tomorrow, so that they can consume more tomorrow,” as a result of climate policy, Peri says. “And what we show is that for that to happen, it means the young have to have a high elasticity of intertemporal substitution, which is just a fancy way of saying that they are willing to transfer more consumption from today to tomorrow” as a result of the effect of climate policy on the value of consumption over time.

Still, based upon the results of computational research done for the research paper, Peri says he and his co-authors determined that selfish incentives for the younger generation proved more quantitatively important for climate policy than those of the old generation.

Goal to spur further research and discussions

Peri says he hopes the economic model for addressing climate change that he and his co-authors created will complement existing research on economic policy related to climate change, including those that rely on altruistic motivations. He says he does not expect lawmakers to adopt the model as policy, but he hopes the paper will spur further research by economists and prompt discussions among policymakers.

Discussions about combatting climate change are particularly timely now, Peri says, given that in 2024 the temperature of the earth reached —before heat-trapping fossil fuels began accumulating in the atmosphere. The Paris Climate Accords, signed by representatives for numerous countries in 2016, aims to keep warming below that level when looking over multiple years.

“This is the great challenge we are facing nowadays, with the announcement in 2024 that we reached 1.5 degrees Celsius above pre-industrial times. So, it’s been the hottest year that we’ve observed since the pre-industrial era,” Peri says. “With the new evidence that has shown that emissions today will have an impact in our lifetime in terms of global warming, we wanted to add our new part … looking at how selfish incentives can help mitigate this great human challenge.”

Did you enjoy this article?  Passionate about economics? Show your support.

Related Articles

Invited by the king of Bhutan, CU Boulder PhD student Clare Gallagher completed the 109-mile Snowman Race to bring attention to the realities of climate change

Usually when Clare Gallagher runs 100 miles, she does it all at once—a day that’s alternately punishing and exhilarating and at the furthest boundaries of what her body can do.

The 109-mile was different. It spanned five days across the Himalayas and saw 16 of the most elite ultramarathoners from around the world traversing multiple mountain passes approaching 18,000 feet.

Clare Gallagher (left) was invited by Bhutanese King Jigme Khesar Namgyel Wangchuck to run the 109-mile Snowman Race ultramarathon. (Photo: Snowman Race)

“As far as ultramarathons go, it was not that crazy a distance—we were doing about a marathon a day,” Gallagher explains. “But it took so, so long because these mountains are just so high. We started in Laya (Bhutan), which is about 13,000 feet in elevation, and went up from there.”

Gallagher, a PhD student in the University of Colorado Boulder Department of Environmental Studies and the Institute of Arctic and Alpine Research (INSTAAR), was invited by the king of Bhutan to participate in the 2024 Snowman Race held at the end of October. It was the second time the race was held—an event envisioned by Bhutanese King Jigme Khesar Namgyel Wangchuck to draw international attention to the stark realities of climate change in Bhutan and around the globe.

“Once we actually got there and were literally on top of these glaciers, I could see his point,” Gallagher says. “His goal is for international trail runners like myself to help share the story of what we saw, and what I saw is that the glaciers are melting.”

Running 100 miles

Before she vividly learned that a journey of 100 miles begins with a single step, however, Gallagher was simply a girl who liked to run. She ran track as an undergraduate at Princeton and kept running in Thailand, where she moved after graduating to teach English. While there, she signed up for the inaugural Thailand Ultramarathon almost on a whim and ended up winning.

Read more about Clare Gallagher's experiences in Bhutan in an .

The races she entered grew in length, and in 2016, at age 24, she ran the Leadville Trail 100 for the first time and won. “I had been reading Outside magazine, and I always looked up to some of the women who preceded me (in ultramarathons),” Gallagher says.

“I thought they were really badass, and trail running seemed a lot more interesting than track—I’d gotten really burned out in undergrad, but to race in a beautiful mountain environment, in places that are so remote, really appealed to me.”

Clare Gallagher (front row, far left in purple shirt) and 15 ultramarathon colleagues from Bhutan and around the world completed the five-day Snowman Race. (Photo: Snowman Race)

She won the 2017 , setting a course record, and the 100-mile Western States Endurance Run in 2019, the Black Canyon 100K in 2022 and the Leadville 100 again, also in 2022. She was invited to run the inaugural Snowman Race in Bhutan that year, but she’d started her PhD program, and her schedule couldn’t accommodate the training.

When she was invited to the second Snowman Race in 2024, despite still being in graduate school, she eagerly accepted. The 16 participants were evenly split between Bhutanese and international runners, “and the Bhutanese runners destroyed us,” Gallagher says with a laugh.

“The physiology of running at altitude is pretty fascinating. A lot of the literature is finding that aspects of this ability are genetic, so if you don’t live at these altitudes and if you can’t afford to be acclimating for a month, your experience is going to be really different. It’s probably the gnarliest race I’ve ever done, and I got wrecked by altitude. People thought I might do well because I’m from Colorado—and I was using an altitude tent beforehand a little bit, but I was also taking my PhD prelims and didn’t want to be sleeping in it. So, I got destroyed.”

She did, most importantly, finish the race, and the slower pace she adopted in acquiescence to the altitude allowed her more time to look around.

‘Please send our message’

The Snowman Race course follows the historic, high-altitude Snowman Trek route, beginning in Laya and ending in Chamkhar, and summitting a series of Himalayan passes—the highest of which is 17,946 feet.

"My experiences in Bhutan reminded me that I also feel a lot of hope and a lot of motivation to do what I can do, and smile while I’m at it," says Clare Gallagher (foreground, running in Bhutan), a CU Boulder PhD student in environmental studies. (Photo: Snowman Race)

“On day three we were up almost to 18,000 feet, and I’m walking and kind of sick with altitude, but I still had never felt the immensity of what I felt in the Himalayas,” Gallagher says. “The race route goes really close to glaciers well over 18,000 feet, and I’ve honestly never felt so scared. I could tell these glaciers were melting and the sun was so hot.

“The story of Bhutan is that these glaciers are melting at a much faster rate than predicted and are then creating these big alpine lakes that break through their levy walls or moraines and flood villages. We ran through one of these most at-risk villages—it takes seven days to get there by horse—and the people who live there don’t want to be forced to move. So, they were saying, ‘Please send our message back to your countries, we’re scared of our glaciers obliterating us.’”

And even though her PhD research focuses on plastic pollution in oceans, “even the issue of plastic pollution was apparent up there,” Gallagher says. “The interconnectedness of our world became so, so apparent up there. A piece of plastic trash up there is going to degrade really fast because of the high altitude and super harsh alpine environment, and then all those chemicals are going to go downstream. There’s not ton of trash in Bhutan, but plastic pollution is still a part of this story.”

She adds that Bhutan, like many smaller nations, is vulnerable to the impacts of climate change despite having one of the smallest carbon footprints on the planet, and she rues that it takes runners from western nations flying there—another carbon-intensive activity—to draw attention to the seriousness of climate change.

“A really surprising take-home from this journey was how spiritual the experience was,” Gallagher says. “All of my fellow Bhutanese runners were praying at mountain passes, and any time there was a meditative stupa, they were stopping and praying to the mountain deities, thanking them for safe passage.

“I really do feel there’s some connection between caring for this planet and each other and all the plants and animals on this planet. I feel like that reverence is something I’ve been missing in my work as an environmentalist. The phrase ‘climate change’ has taken on an almost corporate flavor, but in Bhutan things aren’t emails or PowerPoints or slogans, they’re real. Climate change is not just a phrase; it means melting glaciers. So, I’m interested in taking that depth and reverence for the land and living things and beings and asking, ‘OK, what are our problems here in Colorado? What are our challenges?’”

A hazard of the field in which she’s immersed is extreme climate anxiety, and Gallagher says she’s worked to focus day-to-day on “taking care of what I can take care of and acknowledging my present. My experiences in Bhutan reminded me that I also feel a lot of hope and a lot of motivation to do what I can do, and smile while I’m at it. I feel a lot of gratitude for being alive at this time in history and asking, ‘What are we going to do with this moment?’”

Did you enjoy this article?  Passionate about environmental studies? Show your support.

Related Articles

New research by CU Boulder PhD student Grant Webster finds that the free-fare public transit initiative didn’t reduce ground-level ozone, but may have other benefits

is a big fan of public transit—he takes the bus multiple times a week from his home in east Boulder to the CU Boulder campus, where he’s working on a PhD in economics.

So, two years ago, when he heard about Colorado’s new “” campaign, he was intrigued.

The premise was simple: During the month of August 2022, the state’s Regional Transportation District (RTD) waived fares for all bus and train rides. With this free perk, state leaders hoped to encourage Coloradans to leave their cars at home and take public transit instead. They expected this incentive to reduce ground-level pollution during peak ozone season.

CU Boulder economics researcher and PhD student Grant Webster found that the "Zero Fare for Better Air” public transportation campaign did not significantly reduce ozone pollution in Colorado.

As a bus rider, Webster was optimistic, too. But as an economist, he wanted to see the data.

“When they came out with this policy, I was like, ‘Hey, I ride the bus, I think that’s a cool idea,’” he says. “But I was also curious. Has anybody studied whether these policies actually work?”

Now, he has an answer to that question. “Zero Fare for Better Air” did not significantly reduce ozone pollution in Colorado, Webster reports in published in the journal Transportation Research Part A: Policy and Practice.

Using air pollution, weather, ridership and traffic data, Webster found that public transit ridership did increase during the month of free fares—by roughly 15% to 20%. But even though bus and train travel got a boost, car traffic volumes stayed roughly the same.

“The increase in ridership doesn’t seem to be reducing the number of cars on the roads,” he says. “It might just be transit users taking more rides, or people using RTD that weren’t going to take the ride to begin with.”

Informing policy

Roughly 2% of commuters in the Denver metro area use public transit as their main daily form of transportation—and the proportion is likely even smaller in other parts of the state. So, while public transit ridership saw a sizable bump percentagewise, this bump wasn’t enough to reduce ozone pollution.

For Colorado to see a 1% decrease in ozone pollution, public transit ridership would need to increase by 74% to 192%, Webster finds.

“Even if we had this big increase in ridership, it’s still such a small proportion of commuters, in terms of total pollution contributors, that we wouldn’t expect a huge decrease in ozone pollution overall,” he says.

“The transit infrastructure, the whole environment we live in here in Colorado … people are really reliant on their cars. You’d need a much bigger switch of people’s transit behaviors for this policy to be affecting overall air pollution.”

The findings are a bit of a bummer, but Webster says they’re important nonetheless. They could help policymakers use their limited dollars in different ways—ones that might be more effective at reducing pollution.

The “Zero Fare for Better Air” campaign was funded by Colorado Senate Bill 22-180 and brought back in 2023, but axed in 2024 due to cited budget constraints.

The “Zero Fare for Better Air” campaign was funded by and offered in partnership with the Colorado Energy Office. RTD brought back the campaign for a second year in 2023 and expanded it to include both July and August, while Webster’s research was still underway. But, in 2024, it axed the program, .

Webster also points out that, while the campaign didn’t reduce ozone pollution as intended, it may have had other economic benefits, such as making public transit more affordable for low-income individuals or introducing new riders to the system.

Also, his findings only apply to Colorado, where overall ridership is relatively low. The picture might look very different in cities and states with more robust transit infrastructure and a higher proportion of public transit commuters, he adds. So, policymakers elsewhere shouldn’t completely rule out similar initiatives in their locales.

“In places like New York City or Washington, D.C., this type of policy might have completely different implications,” he says.

Consider other incentives

Overall, the findings suggest that, when deciding whether to drive or take public transit, the cost of the fare is not the most important factor in commuters’ decision-making process. And that’s an important takeaway: To change commuters’ behavior, policymakers may need to consider other, more compelling incentives.

 

You’d need a much bigger switch of people’s transit behaviors for this policy to be affecting overall air pollution.”

 

“When you talk about getting to work, there are so many factors at play,” Webster says. “What’s traffic going to be like? How far away is the bus station? How long do I have to wait? Can I leave in the middle of the day to go run an errand?”

More broadly, as policymakers look for novel ways to slow or halt human-caused climate change, the study also demonstrates the value of considering possible solutions through an economic lens.

“Economics provides a lot of good tools for studying these types of environmental policies,” Webster says. “Can we incentivize people to change their behavior and, as a result, change an environmental outcome? It’s a super important time to focus on the environment and our human impacts on it. And economics can play a role in studying these issues.”

Top image: Riders board a city bus in Denver. (Photo: RTD)

Did you enjoy this article?  Passionate about economics? Show your support.

Related Articles

CU Boulder PhD student Clare Gallagher finds reason for hope amid the complexities of negotiations to craft a U.N. treaty addressing a worldwide crisis

In the past year, Clare Gallagher has gotten very interested in , which she admits is “a really depressing Google search” if you’re not already familiar with it.

Ghost gear is the umbrella term for lost, abandoned or discarded fishing gear that contributes to the crisis of plastic pollution in Earth’s oceans and can trap fish and marine mammals, causing them to die by suffocation or exhaustion. In the upper Gulf of California, for example, to the vaquita porpoise nearing the brink of extinction.

When Gallagher, a PhD student in the University of Colorado Boulder Department of Environmental Studies, joined an observer delegation at the fourth session of the April 23-29 in Ottawa, Canada, she learned that fishing gear is included in a proposed international treaty on plastic pollution that would be discussed at the weeklong gathering.

Clare Gallagher, a PhD student in the CU Boulder Department of Environmental Studies, by a sculpture outside a U.N. treaty negotiating session in Ottawa, Canada. (Photo: Clare Gallagher)

However, after attending several all-day—and sometimes into the night—negotiating sessions, “I learned that fishing gear is almost like a side note to the greater problem. Single-use plastics are so nefarious, and this is the next climate change fight,” Gallagher says.

“To be able to go sit in conference room for 14 hours a day for nine days straight—and the final meetings went until 3 a.m.—I was pretty in awe of the dedication of the people in these meetings. But then at the same time, it was also incredibly frustrating when there’s not a lot of progress made. It’s just the way of global geopolitics, and I was getting a crash course in this—there will be some countries or blocs of countries that don’t want strong treaties, like oil-producing countries, just as there are countries that have been against strong environmental treaties for the last several decades.”

The gathering Gallagher attended was the fourth session of the U.N. Intergovernmental Negotiating Committee on Plastic Pollution and focused on the marine environment. The committee’s stated goal is to have a completed treaty written by the end of the year.

For Gallagher, attending the session not only was eye-opening to the intricacies of global geopolitics, but also brought several other key insights, including:

Abandoned fishing gear is one problem of many in the crisis of plastic pollution in the world’s oceans

“Microplastics were a huge, huge topic at the treaty discussions,” Gallagher says. “From a health standpoint, I was really surprised to see so many endocrinologists there. The endocrine destruction from chemicals that are being added to plastics is linked to the obesity epidemic, to the epidemic of anxiety and depression. It’s actually pretty terrifying.”

Among the discussion topics were , sometimes called nurdles, which are commonly used as a raw material for making plastic products. They are frequently shipped via container, and if pellets ever spill from those containers into a marine environment, the environmental damage and harm to living creatures can be devastating.

“So, some of the discussion was about classifying them as hazardous waste,” Gallagher says.

However, abandoned fishing gear is a big problem

“Ghost gear is the colloquial term,” Gallagher explains. “The more scientific term is abandoned, lost or discarded fishing gear, or ALDFG, and it’s just a terrible thing. Let’s say you a have huge vessel that’s fishing tuna in the Pacific and use purse seines, which are these crazy kilometer-wide nets that can cinch up entire schools of tuna.

“Say that net gets lost or is intentionally cut by crew or just gets stuck on something or there’s a full-on accident. That net will continue to fish whales, dolphins, turtles, you name it after it’s lost contact with the vessel. That’s why we get term ‘ghost,’ because fishing continues to happen in a worst-case scenario.”

Gallagher notes that purse seines typically are made of nylon, which sinks in water because of its density, so they’re not a significant contributor to the Great Pacific Garbage Patch, which is now about the size of Alaska. However, lighter density nets and fishing line made of high-denisty polyethylene wash up on shorelines around the world, “so it’s pretty incredible that this treaty is trying to address fishing gear as its own plastic pollution sector because almost all commercial fishing nets and lines are made of plastic polymers, so this treaty could address industrial, global and local fishing economies.”

CU Boulder PhD student Clare Gallager attended the fourth session of the United Nations Intergovernmental Negotiation Committee on Plastic Pollution as an observer. (Photo: Clare Gallagher)

Many perceive plastic pollution as a symptom a bigger issue

“The biggest thing is production,” Gallagher says, “stopping primary plastic production. That’s one of the things that’s so interesting about this treaty process, because it’s almost the same story, it’s the same players, it’s the same perpetrators as the international debate over fossil fuel emissions.”

In fact, Gallagher notes, the analyzed the affiliations of registered attendees for the session and found almost 200 lobbyists for the fossil fuel and chemical industries were registered.

The problems of plastic pollution are daunting, but there’s room for hope

“I felt, not being a United Nations treaty expert, pretty overwhelmed by the scale at which countries around the world need to compromise and work together to create any international treaty, especially environmental treaties,” Gallagher says. “It’s pretty overwhelming to think this is how humanity governs itself at the top level.

“That being said, I have hope that the most ambitious countries will continue to push for a strong treaty on plastic pollution. I don’t know if remorse is right word, but there is sadness that many of the countries suffering the most from plastic pollution are not producing the plastic. They’re the ones that have to deal with plastic trash and plastic pollution, the ones that have to fight for a strong treaty, and there’s a real power imbalance that I find so disgusting and disturbing.”

Gallagher says one of the most impressive coalitions she observed at the session was the “There was a woman from Easter Island, which, granted, is part of Chile, and she told a story about how every time her young son goes surfing, which is like every day, she has to wash his hair because there’s so much microplastic in it when he’s done.

“People from some of the smallest, poorest countries repeatedly said, ‘This is not complex. We don’t want your trash; we need to stop this.’ I think that bravery and that fight—these Davids taking on Goliaths, as seen in the —is what is going to make the world a better place.”

Did you enjoy this article?  Passionate about environmental studies? Show your support.

Related Articles

La Niña is coming, raising the chances of a dangerous Atlantic hurricane season–an atmospheric scientist explains this climate phenomenon

One of  to the record-breaking global temperatures over the past year—El Niño—, and its opposite, La Niña, is on the way.

Whether that’s a relief or not depends in part on where you live. Above-normal temperatures are still . And if you live along the U.S. Atlantic or Gulf coasts, La Niña can contribute to the .

Pedro DiNezio, a University of Colorado Boulder associate professor of atmospheric and ocean sciences who studies El Niño and La Niña, explains why and what’s ahead.

Pedro DiNezio is a University of Colorado Boulder associate professor of atmospheric and ocean sciences who studies El Niño and La Niña.

What is La Niña?

La Niña and El Niño are the two extremes of a  that can affect weather around the world.

Forecasters know La Niña has arrived when temperatures in the eastern Pacific Ocean along the equator west of South America cool by  (0.9 Fahrenheit) below normal. During El Niño, the same region warms instead.

Those temperature fluctuations might seem small, but they can affect the atmosphere in ways that ripple across the planet.

The tropics have an atmospheric circulation pattern called the , named after Sir Gilbert Walker, an English physicist in the early 20th century. The Walker Circulation is basically giant loops of air rising and descending in different parts of the tropics.

Normally, air rises over the Amazon and Indonesia because moisture from the tropical forests , and it comes down in East Africa and the eastern Pacific. During La Niña, those loops intensify, generating stormier conditions where they rise and drier conditions where they descend. During El Niño, ocean heat in the eastern Pacific instead shifts those loops, so the eastern Pacific gets stormier.

EL Niño and La Niña also affect , a strong current of air that blows from west to east across the U.S. and other mid-latitude regions.

During El Niño, the jet stream tends to push storms toward the , making these typically dry areas wetter. Conversely, mid-latitude regions that normally would get the storms become drier because storms shift away.

This year, forecasters expect a  – likely by late summer. After a strong El Niño, like the world saw in late 2023 and early 2024, conditions tend to swing fairly quickly to La Niña. How long it will stick around is an open question. This cycle tends to swing from extreme to extreme every , but while El Niños tend to be short-lived, La Niñas can last two years or longer.

How does La Niña affect hurricanes?

Temperatures in the tropical Pacific also control wind shear over large parts of the Atlantic Ocean.

Wind shear is a difference in wind speeds at different heights or direction. Hurricanes have a harder time holding their column structure during strong wind shear because stronger winds higher up push the column apart.

La Niña produces less wind shear, removing a brake on hurricanes. That’s not good news for people living in hurricane-prone regions like Florida. In 2020, during the last La Niña, the Atlantic saw a  and 14 hurricanes, and 2021 had 21 tropical storms and seven hurricanes.

Forecasters are already warning that  could , due in large part to La Niña. The tropical Atlantic has also been exceptionally warm, with  for over a year. That warmth affects the atmosphere, causing more atmospheric motion over the Atlantic, fueling hurricanes.

During La Niña, the Walker Circulation intensifies, triggering stronger storms where the air rises. (Graphic: Fiona Martin/NOAA Climate.gov)

Does La Niña mean drought returns to the US Southwest?

The U.S. Southwest’s water supplies will probably be OK for the first year of La Niña because of all the rain over the past winter. But the second year tends to become problematic. A third year, as the region saw in 2022, can lead to .

Drier conditions also fuel  in the West, , when the winds pick up.

What happens in the Southern Hemisphere during La Niña?

The impacts of El Niño and La Niña are almost a mirror image in the Southern Hemisphere.

Chile and Argentina tend to get drought during La Niña, while the same phase leads to more rain in the Amazon.  during the last La Niña. La Niña also , meaning above-average rainfall. The effects aren’t immediate, however. In South Asia, for example, the changes tend to show up a few months after La Niña has officially appeared.

La Niña is , where vulnerable communities are already in a .

Is climate change affecting La Niña’s impact?

El Niño and La Niña are now happening on top of the effects of global warming. That can exacerbate temperatures, as the world saw in 2023, and precipitation can go off the charts.

Since summer 2023, the world has had  of record-breaking global temperatures. A lot of that warmth is coming from the oceans, which are .

La Niña should cool things a bit, but  that drive global warming are still rising in the background. So while fluctuations between El Niño and La Niña can cause , the overall trend is toward a warming world.

Pedro DiNezio is an associate professor of atmospheric and oceanic sciences at the .

This article is republished from  under a Creative Commons license. Read the .

Related Articles

CU Boulder professors explain Earth Day’s history, impact, what it’s become and if it’s still relevant

If you were at the University of Colorado Boulder in April 1970, you were likely aware―very aware―of the first Earth Day on April 22. CU Boulder was all in and almost stretched the day into a full week, kicking things off on April 18 when the campus was dotted with green flags and abuzz with special events, speeches, films, symposiums, rap sessions and panels.

CU Boulder was just one of about 1,500 universities celebrating Earth Day, not to mention 20 million Americans and more than 10,000 cities, churches and other organizations, says Paul Sutter, a CU professor of environmental history.

That first Earth Day went viral long before viral was cool. No social media, no email blasts, no group texts. Just TV, radio, word of mouth and, in Boulder, an old-fashioned paper-and-ink brochure listing the scheduled events.

“One of the remarkable things is that Earth Day came out of nowhere and was organized quickly, bringing together large numbers of activists who had worked separately before and had not put a name to their movement yet,” Sutter says.

CU Boulder scholars Paul Sutter (left) and Steve Vanderheiden have studied Earth Day's history and impact.

“Earth Day was also decentralized, which meant that it manifested itself in different ways in different places. This was one key to its success. In many ways, we’ve forgotten how powerful and radical these events were. Organizing these events helped to democratize environmentalism.”

So what led to that first Earth Day? And have subsequent Earth Days had the same impact?

Some, including Sutter, say the time was right and argue that even though it sprouted quickly, there were forces at work decades before its birth.  

“Americans emerged from WWII concerned about the destructiveness of the war and the state of the global environment―particularly the relationship between population growth and natural resources,” Sutter says. “Early postwar environmental concern was decidedly global.”

And there was worry about the atomic bomb and nuclear technology. “The first detonation of an atomic bomb … was a watershed moment in the nation’s environmental history, and postwar antinuclear activism culminated with the Nuclear Test Ban Treaty of 1963,” Sutter says.

Many cite Rachel Carson’s book on environmental science, Silent Spring, as an added spark as well.

Another factor: The space program, which allowed humans to view Earth from space for the first time. Sutter says that sight gave people “a sense of the planet’s finitude and limits.”

Still relevant?

As successful as that first Earth Day proved to be, after more than a half century, some question whether it’s still relevant, and ask if there’s something else that could make a bigger difference.

Steve Vanderheiden, a CU Boulder professor of political science and environmental studies, says anything that’s been observed annually since 1970 is “bound to have diminishing returns” over time, and that today’s iteration “will be less consequential” than the first one.

 

One of the remarkable things is that Earth Day came out of nowhere and was organized quickly, bringing together large numbers of activists who had worked separately before and had not put a name to their movement yet.”

 

“I don't mean to suggest that there isn't still a role for what Earth Day has become―an occasion to teach about environmental issues or hold events where people reaffirm the importance of environmental protection―but rather that we shouldn't expect it to make much of a difference in public opinion or to build momentum for legislation, which we still need,” Vanderheiden says.

“Those goals are now better served by more oppositional forms of political organization and expression that are more willing or able to challenge the status quo.”

While Vanderheiden says that the original Earth Day was “a powerful focusing event” for the U.S. environmental movement, he sees subsequent Earth Days as having made “relatively little difference,” and that any of the past 40 Earth Days have not swayed public opinion on most environmental issues.

“Part of this is a function of the original Earth Day [that was] intended as a consciousness-raising event, for which it was wildly successful. Consciousness now having already been raised about such issues, these later iterations have less potential to accomplish the same objective.”

Vanderheiden adds that Earth Day has also not evolved to reflect activism or resistance. “That might make it too threatening to the status quo to continue enjoying the wide but shallow support that it now receives. In a way, Earth Day has … maintained its popularity because it doesn't really challenge anything anymore. It’s somewhat like how we still celebrate May Day but almost never with much of its original critical content.”

Interested in learning more about Earth Day? Sutter recommends Adam Rome’s 

Top image: The partly-illuminated Earth rising over the lunar horizon as recorded by Apolo 11; the Earth is approximately 400,000 km away. (Photo: NASA)

Did you enjoy this article?  Passionate about arts and sciences? Show your support.

Related Articles

Harvard scholar Naomi Oreskes, the 2024 Patricia Sheffels Visiting Scholar in Environmental Studies, highlights how free market fundamentalism has thwarted the science of climate change

The best way to define market fundamentalism is in terms of what Ronald Reagan called “the magic of the marketplace.”

“It’s the idea that ‘the free market’ is powerful, efficient, effective, rational and that most problems can best be solved by allowing the market to do its thing,” explained , the Henry Charles Lea Professor of the History of Science at Harvard University and an affiliated professor of earth and planetary science. She added that market fundamentalism also must be understood as a force that has long blocked, and continues to block, climate action.

Oreskes, the 2024 Patricia Sheffels Visiting Scholar in the Department of Environmental Studies, presented some of the findings from her research at a lecture April 4. In it, she detailed a decades-long campaign to cast doubt on science and block political action on climate change—buoyed by the argument that the free market is best poised to tackle the issue.

However, “there is not such a thing as the free market,” Oreskes said. “Markets can be very effective for many kinds of things, but our argument is not all things.”

Naomi Oreskes, the 2024 Patricia Sheffels Visiting Scholar in the Department of Environmental Studies, presented some of the findings from her research at a lecture April 4.

In her 2023 book, written with Eric Conway, , Oreskes began with the “very notion of the free market—this idea that the market exists, it’s a thing, it exists unto itself, it has agency and even wisdom. I think of the metaphor of the invisible hand of the marketplace, which is often talked about as if it’s not a metaphor, as if there actually is an invisible hand,” she said.

“The reality is that we make markets. They have been around since biblical times and are associated with the rise in capitalism, and people have been studying them for just as long—you can find rules for how markets should operate in Leviticus. But there is no such thing as ‘the free market’ and never has been. The reality is that government has always been involved in markets, in protective tariffs … in many cases, governments have created markets.”

In the headlines in the ‘80s

Oreskes began her presentation by displaying a story that appeared on the front page of headlined “Global warming has begun, expert tells Senate.” The expert was James E. Hansen of NASA, described in the story as a leading expert on climate change, who said “that there was no ‘magic number’ that showed when the greenhouse effect was actually starting to cause changes in climate and weather. But he added, ‘It is time to stop waffling so much and say that the evidence is pretty strong that the greenhouse effect is here.’”

Oreskes further noted that in 1992, George H.W. Bush signed the , which he described as “the first step in crucial long-term international efforts to address climate change.”

“So, a few years ago, I got interested in the question ‘What the heck happened?’” Oreskes said. “We had a Republican president and Democratic leaders in Congress, so why didn’t we take those concrete steps that Bush promised us?

“The answer is not a lack of scientific communication. Lots of people at the time thought that scientists just weren’t doing a good enough job explaining the science, but what (Conway and I) showed … was a politically motivated campaign to cast doubt on that science and block political action.”

This has been exacerbated, she said, by negative belief in government and hostility to government action, especially government regulations: “Market fundamentalists will tell you that government needs to get out of the way and let markets do their magic.”

For more than 100 years, she said, organizations like the National Association of Manufacturers have partnered with scientists and economists to stoke hostility toward government regulation, framing it as a backdoor to communism and antithetical their definition of freedom.

 

We’ve had conservative physicists who made common cause with the fossil-fuel industry and libertarian think tanks. Why would educated, intelligent people deny basic scientific findings—especially about things as established as the harms of tobacco use or as big as the hole in the ozone layer? The answer is politics.”

 

“We’ve had conservative physicists who made common cause with the fossil-fuel industry and libertarian think tanks,” Oreskes said. “Why would educated, intelligent people deny basic scientific findings—especially about things as established as the harms of tobacco use or as big as the hole in the ozone layer? The answer is politics.”

Together, politics and business have framed “free enterprise” as one of the United States’ founding principles, but it “appears nowhere in the Declaration of Independence, nowhere in the Constitution, and if you know anything about the history of America in the 19th century, governments at the federal and state level were massively involved in developing the economy.”

American capitalism has not protected freedom, Oreskes said, and “freedom is not protected by our systems of distributing goods and services, but by our forms of government. If you think about it in terms of the political economy, there’s the political part and the economic part. The political part has to be supported by governance; freedom is supported by our laws and also by our civic norms, what we accept as legitimate and what we reject as not legitimate.

“A common American error is the belief that freedom is the absence of state authority. One part of the reason why so many Americans have made this error is because this is what we’ve been told for more than a century by powerful people, powerful organizations and some powerful academics.”

She said that the climate crisis can be seen as a market failure and that free-market fundamentalism has triggered “a race to the bottom.”

Quoting the author Kim Stanely Robinson, Oreskes said, “The invisible hand never picks up the check.”

Did you enjoy this article?  Passionate about environmental studies? Show your support.

Related Articles

‘Stand Up for Climate Comedy’ unites CU Boulder student performers and professional comedians in a show that encourages the audience to laugh together and then work together

The Green Bachelor was not impressed with Oceana Sea and her 2 million followers—despite her name, she hates the water and doesn’t know how to swim. Nor was he impressed with Petrolina Exxon and her daddy’s helicopter. They clearly weren’t there for the right reasons.

Not to spoil the true-eco-love ending, but the Green Bachelor, a marine biologist, was smitten with the contestant who rode her bike to the Green Bachelor mansion and knows the flow of her local watershed.

Pause scene.

"Stand Up for Climate Comedy" is at 7 p.m. April 15 at Boulder Theater, 2032 14th St. Admission is free.

“I think we should say, ‘What is your local watershed and what are you doing to support it, hmm?’” says Elizabeth Smith, a junior majoring in environmental studies.

This followed discussion of defining Oceana as someone who obviously doesn’t know her bodies of water, and advice from Beth Osnes to remember that the sketch is “a physicality thing, so get it up on its feet as soon as you can.”

It was a Tuesday morning in the Climate Change Communication class, and students were laughing at climate change.

Not the reality of it, of course—it’s the defining issue of their generation and there’s nothing funny about it—but in preparation for Stand Up for Climate Comedy April 15 at the Boulder Theater. The show, which is in its ninth year, will feature comedians and science communicators , and , as well as students from the Climate Change Communication class, who write and perform either solo stand-up or group sketches that they create together with support from Osnes and Ben Stasny, a PhD candidate in theater and teaching assistant for the class.

“Comedy has always taken on serious, heavy, depressing social issues,” explains Osnes, a University of Colorado Boulder professor of theatre and dance who teaches the class. “Instead of people just yelling at each other about these issues, approaching them through comedy makes engagement with the issues not only positive, but helps us process them in a way that doesn’t feel overwhelming or hopeless.

“Comedy relies on double meaning. I think it’s easy for us to get stuck in binary thinking, things are one way or the other, and once you get locked into one thought, you’re stuck. Comedy can help us get unstuck, and the gorgeous thing about it is when it works, our response is involuntary, that burst of laughter, and all of a sudden everybody’s having that same response and we’re having it together. It’s golden. When we’re talking about climate change, we need things that are going to help us burst through our set ways of thinking and that we do together.”

Laughing together

Stand Up for Climate Comedy is the brainchild of Osnes and Max Boykoff, a CU Boulder professor of environmental studies, who also are two of the project leaders for , a collective effort that aims to creatively frame and tell the stories surrounding climate change through video, theatre, dance and writing.

Osnes and Boykoff figured that people might have a better time carrying or reframing the burdens of guilt and despair that shadow climate change if they were laughing together rather than shouting at each other. It’s not so much “laugh to keep from crying,” she says, but more “laugh and get moving.”

The first year of Stand Up for Climate Comedy “was basically Max and me downstairs (in the Theatre Building) with a $250 budget,” Osnes says.

Not long after, however, they were approached by representatives from the “who came to us and said, ‘We’re so sick of people screaming at each other; if we gave you $25,000, what would you do with it?’” Osnes recalls.

Beth Osnes (center) works with Lief Jordan (left), Jayden Simisky and Taylor Gutt as they prepare their stand-up comedy performances. (Photos: Rachel Sauer)

They would make the show bigger, they would organize events across the country, they would bring in luminaries of comedy who also know their science and they would integrate students as a key part of the show. That last part—student involvement—is especially key, Osnes says, because students have deep knowledge of the issues of climate change and are demanding action.

Hence the environmental hostility.

‘The seas are rising, and so are tensions!’

“My best bit is, ‘I’m sick of all this environmentally friendly shit. I’m environmentally hostile now,’” says Taylor Gutt, a senior in environmental studies.

“That’s a good bit,” says Lief Jordon, also a senior in environmental studies. “Environmental hostility is funny.”

They’re sitting with Jayden Simisky, a senior in environmental studies, and Cate Billings, a senior majoring in creative technology and design, at the top of a staircase in the Loft Theatre, workshopping the stand-up routines they’re writing.

None of them has performed stand-up before, “but why not, right?” Jordan says with a laugh. “If you’re going to go down, go down big.”

Billings is taking her stand-up in a multimedia direction, complete with a PowerPoint presentation “so it’s a little educational,” she explains. “I have a slide of coral bleaching and I say, ‘Up here on the surface we bleach our assholes, but coral is way ahead of the trend.’”

That earns an appreciative laugh from her classmates. Meanwhile, Simisky is thinking out loud about how to make carbon dioxide funny.

“The biggest thing for me with CO2 is they’re always saying, like, ‘7,000 tons of CO2,’” he says. “So, there’s this whole-ass neighborhood of carbon dioxide in the sky. Maybe something like, ‘There’s so much CO2 in the air that they’re starting to weigh it in terms of cruise ships. I’ve started to live in fear of a boat falling out of the sky.’”

Skyler Behrens (foreground) times her group's comedy sketch on a practice run-through.

That’s good, his classmates agree.

Elsewhere in the theater, Skyler Behrens, a sophomore studying engineering and education, and Claire Grossman, a junior in creative technology and design, are considering what contestants on a climate change-informed “Love Island” would say.

“What if he just says, ‘Wow, that’s hot’?” Behrens suggests.

“That’s perfect,” Grossman says, and soon Behrens is running through the sketch introduction again: “Welcome back, everyone, to the most exciting season of ‘Love Island’ yet! The seas are rising, and so are tensions!”

Nearby, Marcus Witter and Jake Mendelssohn, both seniors in environmental studies, and Austin Villarreal, a junior studying environmental design, are working with Osnes on their sketch involving three guys on a chairlift deciding who has to jump off.

“I don’t really like murder,” Osnes observes. “I think it’s funnier if an act of God knocks you off.”

Many of the students have not done this kind of performance before, and certainly not on a stage the size of Boulder Theater’s. They admit to nerves and to thinking about jokes so much that they stop being funny, but they’re excited, too.

“It helps that we’re doing it together,” notes Danielle Harris, a senior in environmental studies who plays Oceana Sea on “The Green Bachelor,” and her comedy partners nod in agreement.

Did you enjoy this article?  Passionate about creative climate communication? 

Related Articles

Landscape corridors can aid in fire ant spread, but the effects are transient, CU Boulder researcher Julian Resasco shows

As habitat loss and fragmentation continues, many in the scientific community view landscape corridors as important for connecting habitat fragments to maintain biodiversity.

And yet, might those same landscape corridors make it easier for invasive species to spread and cause greater harm to biodiversity?

It’s a question Julian Resasco, an assistant professor in the University of Colorado Department of Ecology and Evolutionary Biology, has been investigating for more than a decade. He now has an answer for one particular invasive species.

CU Boulder researcher Julian Resasco has studied invasive fire ants for more than a decade.

When Resasco first began researching the issue while working on his PhD, he found the perfect setting with the Savannah River Site Corridor Experiment in South Carolina, which is the largest corridor experiment site in the world. He also found an excellent test subject in Solenopsis invicta, more commonly known as fire ants.

Fire ants are considered one of the most problematic invasive species in the United States, to the detriment of native ant species, Resasco notes. Fire ants are native to South America, but have made themselves at home in the United States since the 1930s and today can be found in many southern states.

“The idea behind this experiment was to design an experiment to see how habitat fragmentation, and conversely, corridors, affect the movement of organisms and biodiversity,” Resasco says. “And the Savannah River Site is an 80,000-hectare site owned by the U.S. Department of Energy and administered by the Forest Service, so it’s one of the few places where large-scale experiments like this can happen.”

Resasco says he initially contemplated focusing his research on small mammals, but eventually decided to study fire ants because they are so invasive. They worked well with the idea of potential negative effects related to corridors, and they also worked well for the scale of the experiment.

“Also, it’s very easy to collect data on ants,” he adds. “So, very quickly I had a cool question and lots of data. Because fire ants are very detrimental to co-occurring ants, I could look at how the fire ants respond to the corridors, and what the effect is on the native ants that live with them.”

In some cases, fire ants will raid the nests of native ants, while in others they will simply monopolize the food and resources in areas they share with native ants and crowding them out, Resasco says, noting fire ants are more aggressive than their native counterparts.

Creating a large-scale testing area

To test whether corridors aided the spread of fire ants, the U.S. Forest Service created experimental landscapes called blocks. One block consists of a central patch created by clearing plantation forest, making a better habitat for fire ants, surrounded by three randomly assigned patch types: connected and rectangular or winged. (Rectangular and winged patches were unconnected to the central patch.)

Researchers used pitfall traps to capture ant workers over a period of years, including 2008 and annually from 2014 to 2019, to estimate the density of fire ants and native ants.

Resasco says research he published in 2014 in showed that fire ant biology played an important role in their degree of spread. Specifically, trait differences between monogyne (single egg-laying queen) and polygyne (multiple egg-laying queen) colonies were important predictors of fire ant population densities, their impact on local ants and the effects of corridors.

The Corridor Experiment at the Savannah River Site in South Carolina is an 80,000-hectare site owned by the U.S. Department of Energy and administered by the U.S. Forest Service; it was designed to test the efficacy of corridors for conservation of biodiversity. (Photo: Ellen Damschen)

Notably, monogyne queens taking part in large aerial mating flights will establish new colonies as far as several kilometers away from their natal homes, while polygyne queens disperse over shorter distances.

“When there is only one queen per colony (monogyne), the behavior of the ants is very different,” Resasco explains. “They defend a big territory to keep other fire ants away, whereas in the polygyne social form there are many egg-laying queens per colony and they will not be aggressive toward non-nestmates. Instead of spreading out, they intermingle with each other and establish really high densities, which has more negative effects on the native ants.”

As a result of their respective mating dispersal patterns, Resasco says his 2014 published research showed polygyne fire ants benefitted from land corridors, while monogyne fire ants—aided by their ability to fly above the tree canopy and for longer distances—were readily able to establish new colonies in patches regardless of whether they were connected with corridors.

However, Resasco says he theorized in 2014 that the effects of corridors on polygne fire ants were transient, meaning fire ant density differences between connected and non-connected patches would dimmish over time, as polygyne fire ants fully established themselves in patches. Now, with testing done over the past decade, research shows that is the case, says Resasco, who recently published his .

“Oftentimes, invasive species are invasive because they’re really good at getting around, so corridors might not make a big difference one way or another if the species can readily colonize,” he says. At the same time, fire ants are just one example of invasive species, so there may be cases in which the benefits of land corridors should be carefully weighed against drawbacks.

While meta-analysis articles published in and by Resasco and his colleagues found much evidence of positive effects of corridors and limited evidence of negative effects, Resasco notes that “there could potentially be times when connecting corridors could have some negative effects we should consider,” adding negative effects of landscape corridors are much less studied than positive effects. Study by other researchers on aspects landscape corridors related to fauna, insects and animals is ongoing, he adds.

“The value of research sites like the Corridor Experiment at Savannah River Site is we can develop theories of how things work and test them out on larger-scale models,” Resasco concludes. “That was the value of the study here.”

Top image: a fire ant queen (Photo: Nash Turley)

Did you enjoy this article?  Passionate about ecology and evolutionary biology? Show your support.

Related Articles

Climate change matters to more and more people–and could be a deciding factor in the 2024 election

If you ask American voters what their top issues are,  to kitchen-table issues like the economy, inflation, crime, health care or education.

Fewer than 5% of respondents in  said that climate change was the most important problem facing the country.

Despite this, research  suggests that concern about climate change has had a significant effect on voters’ choices in the past two presidential elections. Climate change opinions may even have had a large enough effect to change the 2020 election outcome in President Joe Biden’s favor. This was the conclusion of  of polling data that we published on Jan. 17, 2024, through the University of Colorado’s .

Matt Burgess is a CU Boulder assistant professor of environmental studies and institute fellow in the Cooperative Institute for Research in Environmental Sciences (CIRES).

What explains these results, and what effect might climate change have on the 2024 election?

Measuring climate change’s effect on elections

We used 2016 and 2020 survey data from the nonpartisan organization  to analyze the relationships between thousands of voters’ presidential picks in the past two elections with their demographics and their opinions on 22 different issues, including climate change.

The survey asked voters to rate climate change’s importance with four options: “unimportant,” “not very important,” “somewhat important” or “very important.”

In 2020, 67% of voters rated climate change as “somewhat important” or “very important,” up from 62% in 2016. Of these voters rating climate change as important, 77% supported Biden in 2020, up from 69% who supported Hillary Clinton in 2016. This suggests that climate change opinion has been providing the Democrats with a growing electoral advantage.

Using two different statistical models, we estimated that climate change opinion could have shifted the 2020 national popular vote margin (Democratic vote share minus Republican vote share) by 3% or more toward Biden. Using an Electoral College model, we estimated that a 3% shift would have been large enough to change the election outcome in his favor.

These patterns echo the results of a . This poll found that more voters trust the Democrats’ approach to climate change, compared to Republicans’ approach to the issue.

What might explain the effect of climate change on voting

So, if most voters––do not rank climate change as their top issue, how could climate change opinion have tipped the 2020 presidential election?

Our analysis could not answer this question directly, but here are three educated guesses:

First, recent presidential elections have been extremely close. This means that climate change opinion would not need to have a very large effect on voting to change election outcomes. In 2020, Biden  by about 10,000 votes–0.2% of the votes cast–and he won Wisconsin by about 20,000 votes, 0.6% of votes cast.

Second, candidates who deny that climate change is real or a problem might turn off some moderate swing voters, even if climate change was not those voters’ top issue. The scientific evidence for climate change being real  that if a candidate were to deny the basic science of climate change, some moderate voters might wonder whether to trust that candidate in general.

Third, some voters may be starting to see the connections between climate change and the kitchen-table issues that they consider to be higher priorities than climate change. For example,  that climate change affects health, national security, the economy and immigration patterns in the U.S. and around the world.

People march from the U.S. Capitol to the White House protesting former President Donald Trump’s environmental policies in April 2017. (Photo: Astrid Riecken/Getty Images)

Where the candidates stand

Biden and former President Donald Trump have very different records on climate change and approaches to the environment.

Trump  climate change a “hoax.”

In 2017, Trump , an international treaty that legally commits countries to reduce their greenhouse gas emissions.

 that decision in 2021.

While in office, Trump rolled back  aimed at protecting the country’s air, water, land and wildlife, arguing that  businesses.

Biden has restored . He has also added several new rules and regulations, including a  to publicly disclose their greenhouse gas emissions.

Biden has   laws that  tens of  to address climate change. Two of those laws were bipartisan.

On the other hand, the U.S.  the world’s largest producer of oil and gas, and the largest exporter of natural gas, during Biden’s term.

In the current campaign, Trump has  subsidies for renewable energy and electric vehicles, to increase domestic fossil fuel production and to roll back environmental regulations. In practice, some of these efforts  from congressional Republicans, in addition to Democrats.

Public  on particular  that .

President Joe Biden speaks about his administration’s work to combat climate change on Nov. 14, 2023. (Photo: Susan Walsh/Associated Press)

Nonetheless, doing something about climate change remains much more popular than doing nothing. For example, a  found 57% of voters would prefer a candidate who supports action on global warming over a candidate who opposes action.

What this means for 2024

 found that between the 2016 and the 2020 presidential elections, climate change became increasingly important to voters, and the importance voters assign to climate change became increasingly predictive of voting for the Democrats. If these trends continue, then climate change could provide the Democrats with an even larger electoral advantage in 2024.

Of course, this does not necessarily mean that the Democrats will win the 2024 election. For example, our study estimated that climate change gave the Democrats an advantage in 2016, and yet Trump still won that election because of other issues. Immigration  for a plurality of voters, and  suggest that Trump currently leads the 2024 presidential race over Biden.

Although a majority of voters currently prefer the Democrats’ climate stances, this need not always be true. For example, Democrats  when their policies , or when they are framed as , , or . Some Republican-backed climate policies,  renewable energy projects, are popular.

Nonetheless, if the election were held today, the totality of evidence suggests that most voters would prefer a climate-conscious candidate, and that most climate-conscious voters currently prefer a Democrat.

Matt Burgess is an assistant professor of environmental studies at the .

This article is republished from  under a Creative Commons license. Read the .

Related Articles