Click the link for a transcript of “Taking the Temperature on Climate Change."

Climate Policy in the United States

Changes in climate are going to affect most, if not all, of us in the U.S. And public opinion has certainly changed on this in the last 10 years. Many more Americans are on board that the climate is changing and that we should do something about it. There's much more support for climate legislation across the board from Democrats and increasingly from Republicans.

Anyone who works on climate was really excited to see the platform Biden ran on, because it was really the first mainstream presidential campaign where climate had played a fundamental role. There's been a lot of discussion aboutthe importance of climate, the damages from climate that are already happening, and what we need to do is take aggressive action in the future to deal with the problem.

But there are specific industries who are going to be harmed by this legislation, and they are quite organized in fighting this legislation, and in funding politicians who fight it, and in funding organizations, either transparently or not, that are fighting climate legislation.

We are closer than we’ve ever been to really meaningful legislation on climate change. The optimistic view is that we’re on the right trajectory and that we’re going to get some part of this done eventually. But we’re not there yet.
 

COP26: Climate Change on the Global Stage

A “COP” is a “Conference of the Parties,” which is an annual meeting of the signatories of the 1992 United Nations Framework Convention on Climate Change. The main focus of Glasgow was to get countries to be very transparent about how they are going to achieve the ambitions for combating climate change that they articulated at the last major COP summit in Paris.

Was it a success? A lot of countries did come to the table in Glasgow and made commitments in ways that they hadn't done before. There were also new, important agreements on certain greenhouse gasses that we've learned recently are pretty damaging, like methane.

Where we failed to make progress was on something that's called “loss and damage.” Many developing countries argue that they are suffering the damages from climate change even though it is a problem that they have not caused, and they are seeking compensation from developed countries who have been the drivers of climate change. That issue was on the table in Glasgow, but it got put off until next year in Egypt.

The Forecast for the Future

Progress is being made. Emissions are falling in the U.S. They're falling in California. They're falling in the EU. They're pretty flat around the world. And these are not just the per capita emissions, but overall emissions are now going down in many parts of the world, which is a huge success.

Where has that progress come from? In part from government policies that have been successful in mitigation. But the driving factor has really been longer decadal investments by both the public sector and the private sector in technologies that allow us to produce energy in a clean way. It’s a combination of long-term public support through taxes and subsidies for the development of these technologies alongside private sector deployment of these technologies at huge scale.
 

It’s important for people to know about these successes. But it’s also important for us to realize what we don’t know. Emissions in different parts of the world are falling, and that’s fantastic. But it’s also true that people are already getting sick, being harmed, and dying because of the changes we’re already experiencing.  We’re poorly adapted to the climate we live in now, much less the climate of a two-degree warmer or three-degree warmer future, and the science on that needs to be much more widely understood.

I think a huge role for us as academics is not only to do the research to understand those questions, but to get that information out into the world. The great thing about the Freeman Spolgi Institute and institutions like FSI is that it's part of our mandate to translate this research out into the broader world. The translation of what we already know is important, as is the imperitive to drill down on and study the things that we don't.

A major bill with bipartisan support in Congress would reward farmers for an unusual harvest. The Growing Climate Solutions Act(link is external) promises billions of dollars for climate-smart agriculture practices, such as planting cover crops to reduce erosion and sequester carbon. The bill highlights farming’s potential as a climate change solution, as well as the challenge of controlling the sector’s growing greenhouse gas emissions. Below, Stanford Earth scientists Inês Azevedo, David Lobell and Rob Jackson discuss the surprising amount of greenhouse gases emitted by farming, how farmland conservation programs can help reverse the trend and what the federal government can do to promote more climate-friendly agriculture, among other issues.

Azevedo is an associate professor in the Department of Energy Resources Engineering at Stanford’s School of Earth, Energy & Environmental Sciences (Stanford Earth). Her research examines the role of food systems in reaching de-carbonized economies. Lobell is the Gloria and Richard Kushel Director of the Center on Food Security and the Environment. He uses unique datasets to study rural areas; his research has shown how reduced soil tillage can increase yields while nurturing healthier soils and lowering production costs. Jackson is the Michelle and Kevin Douglas Provostial Professor of Energy and Environment in Stanford Earth. His work has shown that global emissions of nitrous oxide increased by 30 percent over the past four decades due mostly to large-scale farming with synthetic fertilizers and cattle ranching, and that well-managed soil’s ability to trap carbon dioxide is potentially much greater than previously estimated.

What might the average person be surprised to learn about greenhouse gas emissions from America’s agricultural lands?

Lobell: First, I think people are surprised that the food system actually uses a very small share of fossil fuels, even when you include all the fertilizer production. Second, people are surprised by how many things they think are good, like eating organic or local foods, have very little effect on emissions and can even be worse than conventional alternatives.

Jackson: Many people are aware that fossil fuel use drives most carbon dioxide emissions, but they might not know that more than half of methane and nitrous oxide emissions attributable to human activities come from agriculture.

Azevedo: I think the average person would be surprised to learn agriculture – including livestock, agricultural soils and agricultural production – accounts for about 10 percent of total U.S. greenhouse gas emissions and, in contrast to some other sectors of the economy, they have increased over time.

Does the Growing Climate Solutions Act go far enough to mitigate and reduce emissions? How could it be stronger?

Lobell: I worry that there isn’t enough emphasis on the main greenhouse gases that agriculture contributes to – nitrous oxide and methane – where progress could probably be made a lot faster than for carbon dioxide. Soil carbon is like motherhood and apple pie – nobody is against it – but I wish that half the energy I see going into how to get more carbon into soil was going into how to reduce emissions of the other gases.

How can programs that reward farmers for certain conservation practices help? 

Jackson: The world’s soils contain far more carbon than the atmosphere, but agricultural activities such as plowing have released two hundred billion tons of carbon dioxide to the atmosphere from soils. Conservation programs can help us put some of that carbon back where it belongs, making our soils more fertile and better at retaining water.

Lobell: On one level, these programs can help start the process of making agriculture carbon neutral or even carbon negative. This is important if we want to meet aggressive climate goals. On another level, they can help build a broader political coalition devoted to solving climate change. This might be even more important for climate goals, especially given the disproportionate role of rural states in our federal government.

How should such programs be designed for maximum efficiency and cost-effectiveness?

Lobell: I’m concerned there is a lot of hype out there now on what specific practices can deliver, for example by companies trying to raise large funding rounds on the idea of selling carbon credits. I think it’s important that the programs have a strong system of verification and ability to adjust over time as we learn about what is truly effective.

Jackson: Rather than focusing primarily on carbon dioxide, agricultural incentives would be well served to reduce emissions of methane and nitrous oxide through practices such as better fertilizer and manure management. Methane’s warming potential is 30 times higher than carbon dioxide’s over a century, and nitrous oxide’s warming potential is nearly 300 times higher. Reducing them is a great bang for our climate buck.

From a global perspective, how important is agriculture’s role as a potential climate change solution, and how can policymakers better quantify and track it?

Azevedo: One of the recent things our recent research has shown is that although reducing emissions from fossil fuels is essential for meeting the Paris Agreement goals, other sources of emissions may also preclude its attainment. Specifically, even if all fossil fuel emissions were immediately halted, the achievement of the agreement’s 1.5 degree Celsius maximum temperature increase target would likely not be feasible if global food systems continue along their current trends.

Lobell: I think accelerating public research in this area will be critical, particularly for ways to accurately measure carbon accumulation or emissions reductions on individual farms. If this had been a well-funded area, we might be in a much better position in terms of leveraging all of the private sector enthusiasm for it. Since food is a traded commodity, it will also be important to monitor global land-use change and the extent to which our domestic policies might be having unintended consequences elsewhere.

Despite aquaculture’s potential to feed a growing world population while relieving pressure on badly depleted oceans, the industry has been plagued by questions about its environmental impacts.

But over the years, the diverse industry – which ranges from massive open-ocean salmon cages to family farm freshwater tilapia ponds – has made significant strides toward sustainability, according to a new Stanford-led analysis.

The study notes, however, that in order for the global aquaculture sector to deliver on its full promise, more effective oversight measures are needed to help ensure that its environmentally sound systems are economically viable.

The findings, published March 24 in Nature, could help shape how consumers think about the seafood they buy, and inform governance strategies critical to global food and nutrition security.

“As the demand for seafood around the world continues to expand, aquaculture will keep growing,” said study lead author Rosamond Naylor, the William Wrigley Professor of Earth System Science in Stanford’s School of Earth, Energy & Environmental Sciences (Stanford Earth). “If we don’t get it right, we risk the same environmental problems we’ve seen in land-based crop and livestock systems: nutrient pollution, excessive use of antibiotics and habitat change that threatens biodiversity.”

Twenty years ago, Naylor led a study that sparked controversy by saying farmed fish and shellfish in some cases added pressure to ocean fisheries – instead of relieving it – because carnivorous farm-raised species required large amounts of wild fish for feed. The paper, also published in Nature, prompted a spate of news stories and academic research questioning whether aquaculture was more of an environmental problem than a solution. Environmental groups applauded the study’s focus on aquaculture’s marine ecosystem impacts, while the industry pointed to hopeful developments that were largely ignored, such as ongoing improvements in fish nutrition.

Since then, the volume of global aquaculture production has tripled. In the new paper, aquaculture specialists and scientists from Asia, Europe, South America and the U.S. assessed the state of the industry by synthesizing hundreds of studies done over the past two decades on issues ranging from value chain developments in freshwater aquaculture to the use of wild fish in feeds to seaweed market challenges.

Their analysis considered key challenges and uncertainties, such as climate change’s impact on the industry, low-income producers’ adoption of sustainable seafood certification programs and shellfish and seaweed farmers’ ability to profit from providing ecosystem services, such as carbon capture.

Among the findings: freshwater aquaculture, comprised of nearly 150 species of fish, shellfish and plants, accounts for 75% of farmed aquatic food consumed directly by humans.

“Most aquaculture is about fish people can afford to eat – and most of the farming of aquatic animals happening in Asian countries stays in those countries,” said study co-author David Little, a professor in the University of Stirling Institute for Aquaculture, in the U.K. “It’s having an important impact on food security and rural livelihoods.”

Other regions, including Africa, are increasingly benefitting from the introduction of freshwater aquaculture. But while small freshwater farms are on the rise around the world, there is little oversight of their practices.

The researchers also found that the production of high-value shrimp, salmon and other marine fish rose rapidly, contributing to a significant rise in the share of global fishmeal and fish oil used by aquaculture. Yet, the ratio of wild fish input per fed fish output has dropped almost seven-fold since 1997.

“We have been successful in converting carnivorous fish, such as salmon and trout, largely into vegetarians,” said study co-author Ronald Hardy of the Aquaculture Research Institute at the University of Idaho.

In the study, the researchers call for better management of antimicrobial use in fish farming to limit the development of drug-resistant microbes that threaten both fish and human health, and regulation of marine farm sites. They also recommended incentives for sustainably designed systems to prevent cross-contamination between fish waste and surrounding waters, and a food systems approach to governance that considers nutrition, equity, justice and environmental outcomes and trade-offs across land and sea.

“When done well, aquaculture can play a sustaining role in global food systems by providing expanded food production and livelihood benefits with relatively minimal environmental harm,” said study co-author Dane Klinger, director of aquaculture at Conservation International and PhD graduate of Stanford’s Emmett Interdisciplinary Program in Environment and Resources. “This assessment will help industry, government and other stakeholders navigate the opportunities and obstacles that remain ahead.”

The researchers shared observations from their analysis in a related seminar. Watch it here.

Dust sweeping across the Southeast U.S. in recent days warns of a growing risk to infants and children in many parts of the world. A Stanford-led study focuses on this dust, which travels thousands of miles from the Sahara Desert, to paint a clearer picture than ever before of air pollution’s impact on infant mortality in sub-Saharan Africa. The paper, published on June 29 in Nature Sustainability, reveals how a changing climate might intensify or mitigate the problem, and points to seemingly exotic solutions to reducing dust pollution that could be more effective and affordable than current health interventions in improving child health.

“Africa and other developing regions have made remarkable strides overall in improving child health in recent decades, but key negative outcomes such as infant mortality remain stubbornly high in some places,” said study senior author Marshall Burke, an associate professor of Earth system science in Stanford’s School of Earth, Energy & Environmental Sciences. “We wanted to understand why that was, and whether there was a connection to air pollution, a known cause of poor health.”

Understanding airborne danger

Children under 5 are particularly vulnerable to the tiny particles, or particulate, in air pollution that can have a range of negative health impacts, including lower birth weight and impaired growth in the first year of life. In developing regions, exposure to high levels of air pollution during childhood is estimated to reduce overall life expectancy by 4-5 years on average.

Quantifying the health impacts of air pollution – a crucial step for understanding global health burdens and evaluating policy choices – has been a challenge in the past. Researchers have struggled to adequately separate out the health effects of air pollution from the health effects of activities that generate the pollution. For example, a booming economy can produce air pollution but also spur developments, such as lower unemployment, that lead to better healthcare access and improved health outcomes.

To isolate the effects of air pollution exposure, the Stanford-led study focuses on dust carried thousands of miles from the Bodélé Depression in Chad – the largest source of dust emissions in the world. This dust is a frequent presence in West Africa and, to a lesser extent, across other African regions. The researchers analyzed 15 years of household surveys from 30 countries across Sub-Saharan Africa covering nearly 1 million births. Combining birth data with satellite-detected changes in particulate levels driven by the Bodélé dust provided an increasingly clear picture of poor air quality’s health impacts on children.

Sobering findings and surprising solutions

The researchers found that a roughly 25 percent increase in local annual mean particulate concentrations in West Africa causes an 18 percent increase in infant mortality. The results expand on a 2018 paper by the same researchers that found exposure to high particulate matter concentrations in sub-Saharan Africa accounted for about 400,000 infant deaths in 2015 alone.

The new study, combined with previous findings from other regions, makes clear that air pollution, even from natural sources, is a “critical determining factor for child health around the world,” the researchers write. Emissions from natural sources could change dramatically in a changing climate, but it’s unclear how. For example, the concentration of dust particulate matter across Sub-Saharan Africa is highly dependent on the amount of rainfall in the Bodélé Depression. Because future changes in rainfall over the Bodélé region due to climate change are highly uncertain, the researchers calculated a range of possibilities for sub-Saharan Africa that could result in anywhere from a 13-percent decline in infant mortality to a 12-percent increase just due to changes in rainfall over the desert. These impacts would be larger than any other published projections for climate change impact on health across Africa.

Safeguarding children against air pollution is nearly impossible in many developing regions because many homes have open windows or permeable roofs and walls, and infants and young children are unlikely to wear masks. Instead, the researchers suggest exploring the possibility of dampening sand with groundwater in the Bodélé region to stop it from going airborne – an approach that has been successful at a small scale in California.

The researchers estimate that deploying solar-powered irrigation systems in the desert area could avert 37,000 infant deaths per year in West Africa at a cost of $24 per life, making it competitive with many leading health interventions currently in use, including a range of vaccines and water and sanitation projects.

“Standard policy instruments can’t be counted on to reduce all forms of air pollution,” said study lead author Sam Heft-Neal, a research scholar at Stanford’s Center on Food Security and the Environment. “While our calculation doesn’t consider logistical constraints to project deployment, it highlights the possibility of a solution that targets natural pollution sources and yields enormous benefits at a modest cost.”

Additional co-authors include Eran Bendavid, an associate professor of medicine at Stanford, member of the Maternal andChild Health Research Institute and an affiliate of the Stanford Woods Institute for the Environment; Jennifer Burney and Kara Voss of the University of California San Diego. Burke is also deputy director of the Center on Food Security and the Environment; and a fellow at the Stanford Woods Institute for the Environment, the Freeman Spogli Institute for International Studies and the Stanford Institute for Economic Policy Research.

The research was supported by the National Science Foundation and the Robert Wood Johnson Foundation.

The ocean could produce up to 75 percent more seafood than it does today and drive sustainable economic growth, holding a key role in solving global hunger. Center on Ocean Solutions Co-Director Jim Leape joined Stanford Earth Professor Roz Naylor for a conversation about food security, the current COVID-19 pandemic and how global food policies can better integrate “blue foods” from marine and freshwater systems. 

"COVID-19 is disrupting processed and widely traded seafood products, such as salmon, shrimp and tuna," states Naylor. "However, locally produced and consumed food systems are actually faring much better. This is especially true for some small-scale fisheries, where local fishing groups have taken the initiative to sell seafood locally and new markets are emerging during the COVID-19 period. Production and consumption have become more tightly connected as a result."

Both Leape and Naylor are part of the global Blue Food Assessment, the first comprehensive review of aquatic foods and their roles in the global food system. Naylor will discuss the assessment with collaborators during the Virtual Ocean Dialogues on June 3rd. 

The pair also highlighted promising innovations for sustainable future food systems. "Illegal fishing defeats efforts to manage the resource sustainability and cheats the fishers who are playing by the rules," Leape explains. "And we can end it. Emerging technologies are bringing much greater transparency into the fishing industry."

"If we want healthy oceans in the future, we have to be thinking about a wide range of innovations, and the institutions, financial incentives, and public trust needed to turn these innovations into real market solutions," says Naylor. 

Read the full Stanford ReportQ&A >

Explore the new Blue Food Assessment website >

Learn more about our work curbing illegal fishing >

COVID-19, combined with the effects of ongoing civil conflicts, hotter and drier weather in many areas, and an unfolding locust invasion in Africa and the Middle East, could cut off access to food for tens of millions of people. The world is “on the brink of a hunger pandemic,” according to World Food Program (WFP) Executive Director David Beasley, who warned the United Nations Security Council recently of the urgent need for action to avert “multiple famines of biblical proportions.”

(Watch Beasley’s conversation on food insecurity as a national security threat with his WFP predecessor, Ertharin Cousin, a visiting scholar with Stanford’s Center of Food Security and the Environment.)

Understanding how these conditions – alone or in combination – might affect crop harvests and food supply chains is essential to finding solutions, according to David Lobell, the Gloria and Richard Kushel Director of the Center on Food Security and the Environment. Below, Lobell discusses the connection between immigration and U.S. food security, a counter-intuitive effect of COVID-19 and more.

How could COVID-19 affect global food security?

I think the biggest effects will probably be related to lost incomes for many low-income people. Even if food prices don’t change, potentially hundreds of millions could be pushed into a much more precarious food situation. I’d be especially worried about remittances – the money immigrants in wealthy nations send home to developing nations – falling, since these are a surprisingly large source of stability for many poor people. Beyond the income effects, there are definitely prospects for reduced supply of foods, but I think these are secondary, especially because global stocks right now are quite large.

Another counter-intuitive effect is that the drop in gasoline demand due to social distancing may be a big driver of changes in food prices. A lot of corn demand is for use in ethanol fuel, and corn prices can affect the prices of many other crops. The price of corn has dropped by about 20 percent since February.

What are the biggest risks in terms of food supply?

Three things come to mind. First, for crops that require a lot of labor, there are some indications that planting and harvest activities are being affected. Even though these are usually included as essential activities, they often rely on migrant populations that can no longer cross state or national borders. California is going to be a prime case study in this.

Second, some countries, like Russia, have started to restrict food exports in an effort to calm domestic consumers worried about food shortages. Even if there is enough global supply, there is a risk that supply for importing countries could be curtailed. This was a big part of the food price spikes a decade ago. Now, we have the added potential that exports will be limited by a lack of mobility to get products to the port – for instance, there are reports from South America that towns won’t let trucks through for fear of the virus.

Third, COVID-19 could really limit the ability of governments and international groups to address other crises that emerge. Nearly every year there are at least a few surprises around the world affecting food that are usually handled before they make big news. Things like livestock diseases and crop pest outbreaks, for example. But without the ability to deploy people to assess and fix problems, there is more scope for issues to go unchecked. Right now, the biggest example of this is the desert locust outbreak in Eastern Africa.

What current and/or likely future weather conditions might have significant impacts on food production?

As the globe warms, we continue to see more “surprises” in most years in terms of record hot or dry growing seasons. It’s a bit too soon to say if and where those will emerge this year. Since global food stocks are high, we have some ability to cope with a shock, but if governments are already nervous it may take less to induce export bans and all of the negative effects those entail.

Ahead of the summer harvest, what is the prospect for controlling locust swarms in threatened countries, and how might the swarms further complicate the global food security picture?

If not for COVID-19, this would likely be the biggest development related to food this year. My understanding is that they are spreading fast in Africa and the Middle East, and while they haven’t yet had big effects in the main production regions, the next couple of months will be critical. The hope is that the winds change and drive them back toward the desert areas they came from. If not, there are at least 20 million people at risk of major food security impacts in the region.

Could we see locust swarms in the U.S.? What can we do to prevent them?

Locusts can occur anywhere. A few years back there was a major outbreak in Israel. They haven’t been a big issue in the U.S. because control methods are available, such as widespread spraying. But again, in a time of COVID-19, these types of responses are harder.

What does history teach us about the situation we are in with multiple threats to food security, and how to deal with it?

I think it comes down to a combination of investing in science-based solutions to avoid problems to begin with, and then having good social safety nets for when problems arise. At that level, it’s not really any different than dealing with infectious disease. The absence of any problems is our goal. At the same time, that absence always seems to breed complacency and neglect. Hopefully, the experiences of 2020 will help strengthen support for a society based on facts, science and compassion.

Media Contacts

David Lobell, Center on Food Security and the Environment: (650) 721-6207; dlobell@stanford.edu

Rob Jordan, Stanford Woods Institute for the Environment: (650) 721-1881; rjordan@stanford.edu