By Samuel Myers
Image: Narendra Shrestha/EPA-EFE/REX/Shutterstock
Samuel Myers is a principal research scientist at the Harvard Chan School of Public Health and director of the Planetary Health Alliance.
Feeding a planet inhabited by 10 billion people by mid-century — already a daunting task — is getting harder due to a little-known impact of global warming: the decline of essential nutrients in the world’s staple foods that exist in almost every single person’s diet around the world.
The mechanism by which rising carbon dioxide saps nutrients from our food crops remains somewhat unclear, but the effect is consistent across most plant types from trees to grasses to edible crops: It is reducing the availability of zinc, iron, protein and key vitamins in wheat, rice and several other fundamental grains and legumes.
The implications are huge: By 2050, hundreds of millions of people could slip below the minimum thresholds of these nutrients needed for good health, and more than 2 billion already deficient could see their conditions worsen. And it extends well beyond human nutrition as every animal in the biosphere depends, directly or indirectly, on plant consumption for nutrients.
These findings, which will appear this week as part of the most comprehensive review ever compiled on the two-way relationship between global warming and land use, highlight the urgent need to slash the greenhouse gas emissions that drive climate change. Human activity has increased atmospheric carbon more than 40 percent since the mid-19th century, enough to unleash a deadly onslaught of extreme weather made more destructive by rising seas. Without a drastic drop in emissions, those levels will climb even more quickly over the coming decades.
Scientists from the United Nations' Intergovernmental Panel on Climate Change are meeting in Geneva this week to validate a 30-page summary for policymakers of a 1,000-page underlying report. Food security is high on the agenda.
Nutritional deficiencies continue to take a heavy toll. Zinc deficiency affects the immune system and increases vulnerability to malaria, lung infections and deadly diarrheal diseases, claiming the lives of some 30,000 children younger than 5 each year. Protein deficiency causes stunting and increases infant mortality. Iron deficiency is linked to nearly 60,000 deaths and 34 million “life years” lost to disability or premature death every year, and can also result in decreased work capacity, reduced IQ and anemia.
Humans are deeply vulnerable to reductions in the nutrient content of staple food crops. We get 60 percent of dietary protein, 80 percent of iron and 70 percent of zinc requirements from plants, most of which are losing these nutrients in response to rising carbon dioxide levels.
Research I have co-written indicates that as a result of these emissions, nearly 2 percent of the global population — an extra 175 million people — could become zinc-deficient, and 122 million would no longer get enough protein. Some 1.4 billion women and children younger than 5 would find their iron intake reduced by 4 percent or more. Half a billion in this group risk developing iron-deficiency-related disease.
By 2050, the vitamin B content of rice is expected to drop 17 to 30 percent, upping the risk of deficiencies in folate (B9), thiamine (B1) and riboflavin (B2) for tens of millions of people, especially in regions dependent on rice. All these vitamins are crucial for normal and healthy development.
The reason for this is still a bit of a mystery. There are theories, such as that more carbon dioxide causes plants to produce more starch, which could have a diluting effect whereby plants become carbohydrate-rich and nutrient-poor. But that’s not the case for all nutrients; the science has a long way to go before we have sound answers.
We do know, however, that when the carbon dioxide effect is combined with the impact of climate change on crop yields, we see even larger reductions in the availability of nutrients in the global diet. Compared with a world without these effects, we anticipate a 14 to 20 percentreduction in the global availability of iron, zinc and protein by 2050, which would threaten large segments of the global population with nutrient deficiencies.
Supplements and vitamins could temporarily alleviate some of the health consequences, but these options have existed for decades and have not protected the billions of people who already suffer from nutrient deficiencies, in part because they are difficult to distribute and do not address the underlying cause of malnutrition.
The countries hit hardest are primarily those that have contributed the least to global carbon emissions, particularly nations in South Asia, the Middle East, sub-Saharan Africa and North Africa, and the former Soviet Union. India would also be hit especially hard, and there would be dramatic increases in zinc and protein deficiencies in China, Indonesia, Bangladesh, Brazil, Kenya and other emerging economies.
The bottom line is frighteningly clear: Unless governments dramatically step up their emissions-reduction efforts, nutritional deficiencies and their associated burdens are set to become even more severe and widespread. We cannot wait to act any longer.
By Leah Burrows, SEAS Communications
After years of making progress on an organic aqueous flow battery, Harvard University researchers ran into a problem: the organic anthraquinone molecules that powered their ground-breaking battery were slowly decomposing over time, reducing the long-term usefulness of the battery.
Now, the researchers — led by Michael Aziz, the Gene and Tracy Sykes Professor of Materials and Energy Technologies at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) and Roy Gordon, the Thomas Dudley Cabot Professor of Chemistry and Professor of Materials Science — have figured out not only how the molecules decompose, but also how to mitigate and even reverse the decomposition.
The death-defying molecule, named DHAQ in their paper but dubbed the “zombie quinone” in the lab, is among the cheapest to produce at large scale. The team’s rejuvenation method cuts the capacity fade rate of the battery at least a factor of 40, while enabling the battery to be composed entirely of low-cost chemicals.
The research was published in the Journal of the American Chemical Society.
“Low mass-production cost is really important if organic flow batteries are going to gain wide market penetration," said Aziz. “So, if we can use these techniques to extend the DHAQ lifetime to decades, then we have a winning chemistry.”
“This is a major step forward in enabling us to replace fossil fuels with intermittent renewable electricity,” said Gordon.
Since 2014, Aziz, Gordon and their team have been pioneering the development of safe and cost-effective organic aqueous flow batteries for storing electricity from intermittent renewable sources like wind and solar and delivering it when the wind isn’t blowing and the sun isn’t shining. Their batteries use molecules known as anthraquinones, which are composed of naturally abundant elements such as carbon, hydrogen, and oxygen, to store and release energy.
At first, the researchers thought that the lifetime of the molecules depended on how many times the battery was charged and discharged, like in solid-electrode batteries such as lithium ion. However, in reconciling inconsistent results, the researchers discovered that these anthraquinones are decomposing slowly over the course of time, regardless of how many times the battery has been used. They found that the amount of decomposition was based on the calendar age of the molecules, not how often they’ve been charged and discharged.
That discovery led the researchers to study the mechanisms by which the molecules were decomposing.
“We found that these anthraquinone molecules, which have two oxygen atoms built into a carbon ring, have a slight tendency to lose one of their oxygen atoms when they’re charged up, becoming a different molecule,” said Gordon. “Once that happens, it starts of a chain reaction of events that leads to irreversible loss of energy storage material.”
The researchers found two techniques to avoid that chain reaction. The first: expose the molecule to oxygen. The team found that if the molecule is exposed to air at just the right part of its charge-discharge cycle, it grabs the oxygen from the air and turns back into the original anthraquinone molecule — as if returning from the dead. A single experiment recovered 70 percent of the lost capacity this way.
Second, the team found that overcharging the battery creates conditions that accelerate decomposition. Avoiding overcharging extends the lifetime by a factor of 40.
“In future work, we need to determine just how much the combination of these approaches can extend the lifetime of the battery if we engineer them right,” said Aziz.
“The decomposition and rebirth mechanisms are likely to be relevant for all anthraquinones, and anthraquinones have been the best-recognized and most promising organic molecules for flow batteries,” said Gordon.
“This important work represents a significant advance toward low-cost, long-life flow batteries,” said Imre Gyuk, Director of the Department of Energy’s Office of Electricity Storage program. “Such devices are needed to allow the electric grid to absorb increasing amounts of green but variable renewable generation.”
This research was co-authored by Marc-Antoni Goulet, Liuchuan Tong, Daniel A. Pollack, Daniel P. Tabor, and Eugene E. Kwan, all from Harvard; and Susan A. Odom of the University of Kentucky; and Alán Aspuru-Guzik of the University of Toronto.
The research was supported by the Energy Storage program of the U.S. Department of Energy, the Advanced Research Projects Agency – Energy, the Innovation Fund Denmark, the Massachusetts Clean Energy Technology Center, and Harvard SEAS.
With assistance from Harvard’s Office of Technology Development (OTD), the researchers are seeking commercial partners to scale up the technology for industrial applications. Harvard OTD has filed a portfolio of pending patents on innovations in flow battery technology.
Introducing the 2019-2021 Environmental Fellows
The Harvard University Center for the Environment extends a warm welcome to the newest class of Environmental Fellows: Alyssa Battistoni, Marissa Elizabeth Grunes, Paul Ohno, Jon Proctor, and Adam Slavney. These fellows will join a group of remarkable scholars who will be beginning the second year of their fellowships. Together, the Environmental Fellows at Harvard will form a community of researchers with diverse backgrounds united by intellectual curiosity, top-quality scholarship, and a drive to understand some of the most important environmental challenges facing society.
Faculty Advisor: Katrina Forrester
PhD: Political Science, Yale University
Alyssa Battistoni is a political theorist working at the intersection between environmental politics, political economy, and feminist thought.
Alyssa earned a BA in Political Science from Stanford University, a MSc in Nature, Society, and Environmental Policy from the University of Oxford, and a PhD in Political Science from Yale University, where she studied political theory. Her dissertation examined the history of the economic approach to environmental problems in the twentieth century and its implications for politics. Her academic work has been published in Political Theory and Contemporary Political Theory, and her writing has appeared in The Guardian, The Nation, Dissent, The Chronicle of Higher Education, and Jacobin, where she is a member of the editorial board. She is an associate faculty member at the Brooklyn Institute for Social Research.
As an Environmental Fellow, Alyssa will work with Professor Katrina Forrester of the Department of Government to theorize new approaches to the challenges of climate politics, with particular attention to the role of the state and interaction between state and economy.
MARISSA ELIZABETH GRUNES
MARISSA ELIZABETH GRUNES
Faculty Advisor: James Engell
PhD: English, Harvard University
Marissa Grunes is a scholar of American literature whose dissertation examines the intersection of architecture and environmentalism in nineteenth-century American culture. She will earn her PhD from the English Department at Harvard University in the Spring of 2019. Marissa’s doctoral work brought together architectural history, aesthetic theory, and environmental history to consider the productive relation between the arts and early environmental thought in the nineteenth-century United States. Marissa’s interdisciplinary research has also led her into the medical humanities and the history of science, with work on the emergence of the hospice movement and the cultural history of the Antarctic.
As an Environmental Fellow, Marissa will work under the guidance of Professor James Engell in the English Department on a book about Antarctica for the general reader. Incognita: A Portrait of Antarctica will combine historical research with a synthesis of current ecological, atmospheric, and geophysical findings to offer a journey across the continent. Marissa’s goal is to produce a rigorously-researched book that will capture the imagination of curious readers, drawing them into the threatened world of the Antarctic and its power to transform our planet.
Dept/School: Earth and Planetary Sciences & John A. Paulson School of Engineering and Applied Sciences
Faculty Advisor: Scot Martin
PhD: Chemistry, Northwestern University
Paul Ohno is a physical chemist studying the physical and chemical properties of secondary organic aerosol particles and the implications of these properties for the climate system.
Paul earned his AB in Chemistry from Princeton University in 2014 and his PhD in Chemistry from Northwestern University in 2019. During his PhD studies, he used laser spectroscopy to measure fundamental properties of aqueous interfaces so as to better understand, predict, and control chemical processes that occur there, like groundwater pollutant capture at the mineral/water interface.
As an Environmental Fellow, Paul will work with Professor Scot Martin of the John A. Paulson School of Engineering and Applied Sciences and the Department of Earth and Planetary Sciences. Their work will focus on developing and applying spectroscopic techniques to directly determine physical and chemical properties, such as viscosity and diffusivity, of secondary organic aerosol particles while they remain in suspension. Paul is also a 2019 Schmidt Science Fellow.
Dept/School: Earth and Planetary Sciences & John A. Paulson School of Engineering and Applied Sciences
Faculty Advisor(s): Peter Huybers, Jim Stock, and others
PhD: Agricultural and Resource Economics, University of California, Berkeley
Jon Proctor develops and pairs methods in econometrics, spatial statistics and machine learning with global socio-environmental datasets to empirically estimate the relationships that govern our climate and agricultural systems. For example, in recent work Jon uses volcanic eruptions as natural experiments to provide the first empirically-based estimates of how solar geoengineering might impact agricultural yields. In a second strand of research he develops, characterizes and democratizes new algorithms for planetary-scale monitoring using satellite imagery. Jon graduated from Stanford University in 2014 where he studied Earth Systems; he will earn his PhD in Agricultural and Resource Economics from the University of California, Berkeley in August, 2019.
As a joint Data Science and Environmental Fellow, Jon will continue to explore 1) how human activity alters the transfer of sunlight through the atmosphere, and in turn, how these changes in radiation impact crop productivity and 2) how remote sensing measurements can be efficiently made and appropriately applied to quantify relationships in socio-environmental systems. He is excited to pursue these questions with Peter Huybers, Jim Stock, and others. When he’s not at his desk, you can find Jon backpacking, rock climbing, or teaching and performing improvisational theater.
Department: Chemistry and Chemical Biology
Faculty Advisor: Jarad Mason
PhD: Chemistry, Standford University
Adam Slavney is a chemist and materials scientist who makes and studies porous materials for the capture, storage, and chemical transformation of environmentally important gases.
Adam earned his PhD in chemistry from Stanford University in 2019. His doctoral work focused on the development of halide double perovskites as optoelectronic materials, particularly in the realm of photovoltaics. Adam discovered several new double perovskite phases, extensively studied their promising optical absorption, carrier transport, and defect properties, and outlined simple rules to accurately predict and describe the electronic structures of all halide double perovskites. While at Stanford he held a Stanford Graduate Fellowship and the Franklin Veatch Memorial Fellowship. Prior to Stanford, Adam received his BA in chemistry in 2014 from Washington University in St. Louis.
As an Environmental Fellow, Adam will work with Jarad Mason from the Department of Chemistry and Chemical Biology. His research will focus on the synthesis of novel porous materials such as nanocrystal frameworks and intrinsically-porous liquids. These materials will be used to separate and store technologically important gases such as hydrogen and oxygen as well as to capture and remediate environmental pollutants such as carbon monoxide and the nitrogen oxides. Adam’s work will be supported by the Arnold O. Beckman Postdoctoral Fellowship in the Chemical Sciences.
By Caitlin McDermott-Murphy, Department of Chemistry and Chemical Biology
About one fourth of the Northern Hemisphere is covered in permafrost. Now, these permanently frozen beds of soil, rock, and sediment are actually not so permanent: They’re thawing at an increasing rate.
Human-induced climate change is warming these lands, melting the ice, and loosening the soil. This may sound like any benign Spring thaw, but the floundering permafrost can cause severe damage: Forests are falling; roads are collapsing; and, in an ironic twist, the warmer soil is releasing even more greenhouse gases, which could exacerbate the effects of climate change.
From the first signs of thaw, scientists rushed to monitor emissions of the two most influential anthropogenic (human-generated) greenhouse gases (carbon dioxide and methane). But until recently, the threat of the third largest (nitrous oxide) has largely been ignored.
In the Environmental Protection Agency’s (EPA) most recent report (from 2010), the agency rates these emissions as “negligible.” Perhaps because the gas is hard to measure, few studies counter this claim.
Now, a recent paper shows that nitrous oxide emissions from thawing Alaskan permafrost are about twelve times higher than previously assumed.
“Much smaller increases in nitrous oxide would entail the same kind of climate change that a large plume of CO2 would cause” says Jordan Wilkerson, first author and graduate student in the lab of James G. Anderson, the Philip S. Weld Professor of Atmospheric Chemistry at the Harvard John A. Paulson School of Engineering and Applied Sciences.
Since nitrous oxide is about 300 times more potent than carbon dioxide, this revelation could mean that the Arctic—and our global climate—are in more danger than we thought.
In August 2013, members of the Anderson lab (pre-Wilkerson) and scientists from the National Oceanic and Atmospheric Administration (NOAA) traveled to the North Slope of Alaska. They brought along a plane just big enough for one (small) pilot.
Flying low, no higher than 50 meters above the ground, the plane collected data on four different greenhouse gases over about 310 square kilometers, an area 90 times larger than Central Park. Using the eddy-covariance technique—which measures vertical windspeed and the concentration of trace gases in the atmosphere—the team could determine whether more gas went up than down.
In this case, what goes up, does not always come down: Greenhouse gases rise into the atmosphere where they trap heat and warm the planet. And, nitrous oxide poses a second, special threat: Up in the stratosphere, sunlight and oxygen team up to convert the gas into nitrogen oxides, which eat at the ozone. According to the EPA, atmospheric levels of the gas are rising, and the molecules can stay in the atmosphere for up to 114 years.
When Wilkerson joined the lab in 2013, the nitrous oxide data was still raw, untouched. So, he asked if he could analyze the numbers as a side-project. Sure, Anderson said, go right ahead. Both of them expected the data to confirm what everyone already seemed to know: Nitrous oxide is not a credible threat from permafrost.
Wilkerson ran the calculations. He checked his data. He sent it to Ronald Dobosy, the paper’s second author, an Atmospheric Scientist and eddy-covariance expert at the Oak Ridge Associated Universities (ORAU), working at NOAA. “I was skeptical that anything would come of it,” Dobosy says.
After triple checks, Wilkerson had to admit: “This is widespread, pretty high emissions.” In just one month, the plane recorded enough nitrous oxide to fulfill the expected cap for an entire year.
Still, the study only collected data on emissions during August. And, even though their plane covered more ground than any previous study, the data represents just 310 of the 14.5 million square kilometers in the Arctic, like using a Rhode Island-sized plot to represent the entire United States.
Even so, a few recent studies corroborate Wilkerson’s findings. Other researchers have used chambers—covered, pie plate-sized containers planted into tundra—to monitor gas emissions over months and even years.
Other studies extract cylindrical “cores” from the permafrost. Back in a lab, the researchers warm the cores inside a controlled environment and measure how much gas the peat releases. The more they heated the soil, the more nitrous oxide leaked out.
Both chambers and cores cover even less ground (no more than 50 square meters) than Anderson’s airborne system. But together, all three point to the same conclusion: Permafrost is emitting far more nitrous oxide than previously expected. “It makes those findings quite a bit more serious,” Wilkerson says.
Wilkerson hopes this new data will inspire further research. “We don’t know how much more it’s going to increase,” he says, “and we didn’t know it was significant at all until this study came out.”
Right now, eddy-covariance towers—the same technology the Anderson crew used in their plane—monitor both carbon dioxide and methane emissions across the Arctic. Anderson was the first to use airborne eddy-covariance to collect data on the region’s nitrous oxide levels. And, apart from the small-scale but significant chamber and core studies, no one is watching for the most potent greenhouse gas.
Since the Arctic is warming at almost twice the rate of the rest of the planet, the permafrost is predicted to thaw at an ever-increasing rate. These warm temperatures could also bring more vegetation to the region. Since plants eat nitrogen, they could help decrease future nitrous oxide levels. But, to understand how plants might mitigate the risk, researchers need more data on the risk itself.
In his place, Wilkerson hopes researchers hurry up and collect this data, whether by plane, tower, chamber, or core. Or better yet, all four. “This needs to be taken more seriously than it is right now,” he says.
The permafrost may be stuck in a perpetual climate change cycle: As the planet warms, permafrost melts, warming the planet, melting the frost, and on and on. To figure out how to slow the cycle, we first need to know just how bad the situation is.
Image: David S. Sayres