CLIMATE CHANGE
Climate change may reduce life expectancy by half a year, study suggests
On its own, a 1°C temperature rise might shave off about 5 months, with women and people in developing nations disproportionately affected
The cost of climate change may be six months off the average human lifespan, according to a study published January 18, 2024, in the open-access journal PLOS Climate by Amit Roy from Shahjalal University of Science and Technology and The New School for Social Research, U.S.
Temperature and rainfall — two telltale signals of climate change — cause myriad public health concerns, from the acute and direct (e.g., natural disasters like flooding and heat waves) to the indirect yet equally devastating (e.g., respiratory and mental illnesses). While impacts like these are observable and well documented, existing research has not established a direct link between climate change and life expectancy.
To clarify this relationship, the author evaluated average temperature, rainfall, and life expectancy data from 191 countries from 1940-2020, using GDP per capita to control for drastic differences between countries.
In addition to measuring the isolated impacts of temperature and rainfall, the author designed a first-of-its-kind composite climate change index, which combines the two variables to gauge the overarching severity of climate change.
Results indicate that in isolation, a global temperature increase of 1°C is associated with an average human life expectancy decrease of approximately 0.44 years, or about 5 months and 1 week. A 10-point increase in the composite climate change index — which accounts for both temperature and rainfall — is expected to decrease the average life expectancy by 6 months. Women and individuals in developing nations are disproportionately affected.
Beyond the results of this study, Dr Roy is hopeful that the composite climate change index will standardize the global conversation about climate change; become a usable metric for the nonscientific public; and encourage collaboration and even friendly competition among countries to combat the impacts of climate change.
Mitigating greenhouse gas emissions and adapting to a changing environment are of particular importance, the author says.
To complement this large-scale approach, the author suggests localized future studies that consider specific severe weather events (e.g., wildfires, tsunamis, and floods), the impacts of which cannot be fully captured through analyzing temperature and rainfall alone.
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In your coverage please use this URL to provide access to the freely available article in PLOS Climate: https://journals.plos.org/climate/article?id=10.1371/journal.pclm.0000339
Citation: Roy A (2024) A panel data study on the effect of climate change on life expectancy. PLOS Clim 3(1): e0000339. https://doi.org/10.1371/journal.pclm.0000339
Author Countries: Bangladesh, US
Funding: The author received no specific funding for this work.
JOURNAL
PLOS Climate
METHOD OF RESEARCH
Computational simulation/modeling
SUBJECT OF RESEARCH
People
ARTICLE PUBLICATION DATE
18-Jan-2024
AMS presidential forum to address “Climate Science as Service to Society”
The opening keynote session at the American Meteorological Society’s 104th Annual Meeting in Baltimore will feature a discussion on how to overcome communication and societal barriers limiting the utilization of climate science.
Meeting Announcement[Boston, MA—January 17, 2024] The American Meteorological Society (AMS) will open its 104th Annual Meeting with a Presidential Forum on how to advance society’s acceptance and use of climate science. Distinguished atmospheric scientist Dr. Kerry Emanuel will moderate a “fireside chat” with Monica Medina, President and CEO of the Wildlife Conservation Society and former Deputy Assistant Secretary at the State Department, and Bob Inglis, Executive Director of RepublicEn.org and former congressman from South Carolina. The Forum, with opening remarks by AMS President Brad Colman, will take place Sunday, 28 January, from 4 to 5:15 p.m. U.S. Eastern Time at the Baltimore Convention Center and will be livestreamed on the conference website.
The majority of U.S. adults see climate change as a major threat to the country, yet among both politicians and the public, the issue fails to receive priority attention. Climate science and scientists are often the subjects of misinformation and disinformation campaigns, as well as more personal attacks. New approaches may be needed to overcome these and other barriers that limit the reach and impact of climate science, and of science-based responses to environmental change.
“With climate and environmental change affecting society in dramatic and rapidly accelerating ways, climate science, and the professions that use it, are absolutely vital to surviving upheaval and building a future in which humans can thrive,” says Colman. “We are informing flood infrastructure planning, warning the public about changes in dangerous weather, studying how global climate change occurs, and a great deal more. In recognition of our meeting theme, ‘Living in a Changing Environment,’ I’m pleased to share the stage with two people who have important stories to tell about how we can help our science reach more people, overcome political barriers, and have greater impact.”
Read more about the AMS 2024 Presidential Forum.
Butterflies could lose spots as climate warms
IMAGE:
A FEMALE WITH THREE SPOTS ON THE HINDWING
view moreCREDIT: PROFESSOR RICHARD FFRENCH-CONSTANT
Female Meadow Brown butterflies have fewer spots if they develop in warmer weather – so climate change could make them less spotty, new research shows.
University of Exeter scientists found females that developed at 11°C had six spots on average, while those developing 15°C had just three.
The findings challenge long-held scientific views about why these butterflies have varying numbers of spots.
“Meadow Browns always have large ‘eyespots’ on their forewings, probably for startling predators,” said Professor Richard ffrench-Constant, from the Centre for Ecology and Conservation on Exeter’s Penryn Campus in Cornwall.
“They also have smaller spots on their hindwings, probably useful for camouflage when the butterfly is at rest.
“Our findings show that fewer of these hindwing spots appear when females experience higher temperatures during their pupal stage (in a chrysalis before emerging as a butterfly).
“This suggests the butterflies adapt their camouflage based on the conditions. For example, with fewer spots they may be harder to spot on dry, brown grass that would be more common in hot weather.
“We did not observe such a strong effect in males, possibly because their spots are important for sexual selection (attracting females).”
Since the classic work of biologist EB Ford, eyespot variation in the Meadow Brown butterfly has been used as an example of “genetic polymorphism” (the co-existence of multiple genetic forms in a single population).
However, the new study shows the eyespot variation is caused by thermal plasticity (the ability to react to changing temperatures).
“This is a family story for me, as my father collected butterflies for EB Ford here in Cornwall,” Professor ffrench-Constant said.
“In the new study, we looked at current Cornish populations – collecting males and females from the same field every day throughout the flight season – and historical collections from Eton and Buckingham.”
The researchers predict that spotting will decrease year on year as our climate warms.
Professor ffrench-Constant added: “This is an unexpected consequence of climate change. We tend to think about species moving north, rather than changing appearance.”
Meadow Browns spend about 28 days in the pupal stage, usually emerging in late spring in the UK.
The paper, published in the journal Ecology and Evolution, is entitled: “Eyespot variation and field temperature in the Meadow Brown butterfly.”
A female Meadow Brown with one spot on its hindwing
Spotless hindwings may help with camouflage in hot and dry conditions. The forewing eyespot can be hidden by the hindwings
Spotless hindwings may help with camouflage in hot and dry conditions. The forewing eyespot can be hidden by the hindwings
CREDIT
Professor Richard ffrench-Constant
Professor Richard ffrench-Constant
JOURNAL
Ecology and Evolution
ARTICLE TITLE
Eyespot variation and field temperature in the Meadow Brown butterfly
ARTICLE PUBLICATION DATE
17-Jan-2024
The heat is on: UMass Amherst scientists discover southern Africa’s temps will rise past the rhinos’ tolerance
New research shows that rising temperatures caused by climate change are impacting the remaining black and white rhinoceros populations on the African continent, suggests taking steps to mitigate impact now
Peer-Reviewed PublicationIMAGE:
BOTH BLACK AND WHITE RHINOS, LIKE THIS ONE AT KRUGER NATIONAL PARK, SOUTH AFRICA, ARE THREATENED BY CLIMATE CHANGE.
view moreCREDIT: SAM FERREIRA
January 17, 2024
The Heat is on: UMass Amherst Scientists Discover Southern Africa’s Temps Will Rise Past the Rhinos’ Tolerance
New research shows that rising temperatures caused by climate change are impacting the remaining black and white rhinoceros populations on the African continent, suggests taking steps to mitigate impact now
AMHERST, Mass. – Southern Africa contains the vast majority of the world’s remaining populations of both black and white rhinoceroses (80% and 92%, respectively). The region’s climate is changing rapidly as a result global warming. Traditional conservation efforts aimed at protecting rhinos have focused on poaching, but until now, there has been no analysis of the impact that climate change may have on the animals. A research team from the University of Massachusetts Amherst has recently reported in the journal Biodiversity that, though the area will be affected by both higher temperatures and changing precipitation, the rhinos are more sensitive to rising temperatures, which will quickly increase above the animals’ acceptable maximum threshold. Managers in national parks should begin planning adaptations to manage the increased temperatures in the hopes of preserving a future for the rhinoceroses.
The African continent has seen its average monthly temperatures rise by .5 – 2 degrees Celsius over the past century, with up to another two degrees of warming projected for the next 100 years, according to the Intergovernmental Panel on Climate Change’s (IPCC) high greenhouse gas emissions scenario. It is also well known that the changing climate will disrupt historical precipitation patterns—but which of these, temperature or rainfall, will have the most impact on a species, like white and black rhinos, that have long been the target of conservation efforts?
The question is especially important for rhinos because they don’t sweat, and instead cool themselves off by bathing and finding shade.
“Generally speaking, most, if not all, species will, in one way or another, be negatively affected by the changing climate,” says lead author Hlelowenkhosi S. Mamba, who completed this research as part of her graduate studies at UMass Amherst. “It is therefore important for conservationists to conduct macroecological assessments over large areas to catch trends and model futures for some of the world’s most vulnerable species to prepare to mitigate climate change’s effects, hence minimizing global biodiversity losses.”
To understand how our changing climate will affect rhino populations, Mamba and senior author Timothy Randhir, professor of environmental conservation at UMass Amherst, focused their efforts on the five large national parks in South Africa, Namibia, Zimbabwe, Kenya, Botswana, Tanzania and eSwatini that are home to most of the rhinos. The parks represent diverse landscapes.
Mamba and Randhir then modelled two scenarios for each of the parks: the IPCC’s high-emissions scenario and a more moderate emissions scenario. They projected temperature and precipitation for each of the scenarios out to 2055 and 2085 to arrive at a probability that each park would remain suitable for the rhinos.
They found that each park will see approximately 2.2 ºC warming by 2055 and 2.5 ºC by 2085 under the moderate emissions scenario. Under the high emissions scenario, each park will be warmer by approximately 2.8 ºC in 2055 and 4.6 ºC in 2085.
Nearly every park will become increasingly drier as emissions increase, with the exception of one, Tsavo West National Park in Kenya, which will see more rainfall.
This is all very bad news for the rhinos, because the team also found that, though the change in precipitation will not be ideal for the rhinos, the changes in temperature are greater than what the species can bear.
“The temperature conditions in all study parks will become increasingly unsuitable for both species, but it is predicted that white rhinos will be affected earlier than black rhinos,” the authors write. “All the parks are showing drastic changes in the occurrence probability of rhinos.” And under the high-emissions scenarios, the probability of occurrence of either species shrinks to zero by 2085.
The worst news involves Etosha National Park, in Namibia, and Hlane National Park, in eSwatini, both of which will become too warm for rhinos in either scenario.
But to be forewarned is to be forearmed. “This paper highlights the importance of using climate predictions for both park and rhino management,” says Randhir. “We propose that park managers think now about increasing water supplies, tree cover, watching for stress and planning to allow rhino migration as the world warms.”
JOURNAL
Biodiversity
ARTICLE TITLE
Exploring temperature and precipitation changes under future climate change scenarios for black and white rhinoceros populations in Southern Africa
Tackling the effect of climate change on diarrheal diseases
Thanks to a Horizon Europe grant, Amsterdam UMC together with the Amsterdam Institute for Global Health and Development, is set to lead a global consortium to improve policies and interventions
Diarrhoea is, globally, the second largest cause of death for children under 5. Contributing to more than 500,000 deaths, only pneumonia kills more children each year. Climate change, driving increased flooding and droughts, threatens the fragile progress made in reducing the burden of diarrheal disease over the past decades. Together with the Amsterdam Institute of Global Health and Development, Amsterdam UMC is set to lead a global consortium in the hunt for improved interventions.
"We see that the impact of climate change on diseases transmission depends on the constantly changing interaction between climate events, local vulnerabilities and exposure to disease-causing microorganisms,” says Vanessa Harris, Assistant Professor of Global Health at Amsterdam UMC. "For example, sudden heavy rain can cause sewers to overflow and contaminate water supplies or increasing temperatures can cause some pathogens to live longer outside the body,” Harris adds.
Mapping the terrain
To facilitate effective policy responses in countries that are the most vulnerable to the impacts of climate change, more knowledge is necessary. For Harris’ consortium the initial aim is to understand how climate change’s impact on water supplies and the environment will affects the spread of key pathogens and, thus, the risk of contracting diarrheal disease. "By bridging this knowledge gap, we can map which areas are more at risk and why, allowing communities and policy makers to prepare and adapt locally," says Harris. “We'll do this by bringing together a broad range of experts – from climate experts and engineers to anthropologists, health economists, and public health experts – and then using broad-scale modelling and community-based case studies to describe the consequences of climate change on diarrheal burden and identify which local interventions will be most effective into the future.”
Firsthand experience
Dr. Dzidzo Yirenya-Tawiah and Dr. Adelina Mensah, both environmental scientists at the University of Ghana, have conducted multiple community-based studies and seen the effects of climate change on health first hand.
"Many of our fishing communities are exposed to frequent flooding events from sea level rise, storm surges and erratic rainfall events, which sometimes all occur at the same time and have devastating consequences on infrastructure and water supplies. Quality of surface and groundwater is especially compromised through unknown pathways of disease transmission. With limited alternative resources, health risks are exponentially increased," says Mensah.
Horizon Grant
Ghana is not the only country where case studies will be performed, the consortium will also carry out research in Tanzania, Romania and Italy. In all four countries, case study sites are chosen due to their susceptibility to both flooding and drought. However, there are also individual characteristics that will provide the consortium with unique insights. For example, in Naples, proximity to farming and agriculture, coupled with an ageing urban water infrastructure provides added risks. Haydom, Tanzania is an extremely rural setting with high rates of malnutrition and poverty and increased exposure to food insecurity.
Dr. Estomih Mduma is a Public Health researcher at Haydom Lutheran Hospital and sees how diarrhoea diseases are a major cause of hospital admission, child morbidity and mortality in the hospital. The limited accessibility to water compromises the effort to reduce the burden of diarrhoea in this vulnerable population. These vulnerabilities are part of what the SPRINGS consortium plans to tackle, and thanks to a Horizon grant worth 6.5m euros, the project will draft concrete policies that are ready to be implemented.
"We want to get to the stage where we can predict local and national risks and use this evidence to shape policy. This means understanding where water quality and pathogen surveillance needs to be performed to support communities and governments in prioritising their limited resources across health and environmental sectors. Ultimately, combing better mapping and more surveillance coupled with targeted interventions should reduce illnesses and deaths,” concludes Harris.
The SPRINGS consortium consists of Amsterdam UMC, AIGHD, the Norwegian Meteorological Institute, the University of Virginia, the University of Ghana, the London School of Health and Tropical Medicine, Three o'Clock, Aarhus University, the IHE Delft Institute for Water Education, The Abdus Salam International Centre for Theoretical Physics, the Vrije Universiteit Amsterdam, the University of Naples, the Haydom Lutheran Hospital, AQUATIM, the University of Bucharest and the Dutch National Institute for Public Health and the Environment (RIVM).
Focus on biological processes does not capture the whole picture
Call for a Comprehensive View of the Marine Biological Carbon Pump and its role in Climate Change
The ocean contains about 60 times more carbon than the atmosphere, in part due to a key process in the marine carbon cycle called the biological carbon pump (BCP). In this process, carbon dioxide (CO2) is converted to organic matter through photosynthesis and subsequently sinks as the so-called “export flux” from the surface ocean waters to the deep sea. As it sinks, bacterial decomposition processes break down the organic matter back into inorganic carbon, thus storing CO2 in the interior ocean. The BCP keeps atmospheric CO2 levels significantly lower than they would be in a hypothetical world without the BCP. So far, so good. But one crucial aspect is often overlooked, says Dr Ivy Frenger, a climate researcher at the GEOMAR Helmholtz Centre for Ocean Research Kiel: “You have to consider the ocean circulation, because it determines how much of the biologically produced CO2 can actually accumulate in the interior ocean in the long term, isolated from exchange with the atmosphere.” Looking at the effect of the BCP only in terms of the export flux is like trying to explain the balance of a bank account by looking only at the deposits. “But there are gains and losses.”
Changes in the BCP are an important research topic in the context of climate change. Ivy Frenger notes that when considering the impact of the BCP on atmospheric CO2, it is common to focus on the export flux and neglect the ocean circulation. She and six international colleagues have therefore published an opinion paper entitled “Misconceptions of the marine biological carbon pump in a changing climate: Thinking outside the 'export' box”.
In their paper, the scientists aim to address the misconception that there is a direct link between the global export flux - equivalent to deposits - and the biogenic storage of CO2 in the ocean, and hence, atmospheric CO2 – the equivalent to the bank account balance. “There is no such simple correlation,” says Dr Frenger. The “withdrawal” side also needs to be taken into account.
A much simpler and scientifically more accurate approach, she says, would be to directly estimate the CO2 reservoir resulting from biological processes in the interior ocean. Such an estimate can be made by measuring the oxygen content of the ocean's interior along with its physical state, such as temperature. Changes in these variables under climate change would also explain a seemingly paradoxical response of the BCP under anthropogenic climate change: Despite a decreasing export flux, carbon storage due to the biological pump in the interior ocean increases. This is because changes in ocean circulation delay the return of biologically stored carbon from the ocean interior to the surface. As in the bank account analogy: while the deposits are lower, if the withdrawals are reduced to an even greater extent there will be a net increase. Accordingly, for climate change, this feedback results in more CO2 being stored in the ocean's interior than would be the case without the biological carbon pump. Co-author Angela Landolfi remarks: “It is important to note that this effect is small when compared to the continuing massive anthropogenic CO2 emissions from fossil fuels”.
The scientists hope that their opinion paper and proposed approach will contribute to a clearer understanding of the influence of the marine biological carbon pump on atmospheric CO2 in a changing world. A broader view of the biological carbon pump is particularly important for proposals to remove CO2 from the atmosphere through marine CDR approaches, such as artificially stimulating marine biology.
JOURNAL
Global Change Biology
METHOD OF RESEARCH
Literature review
SUBJECT OF RESEARCH
Not applicable
ARTICLE TITLE
Misconceptions of the marine biological carbon pump in a changing climate: Thinking outside the “export” box
ARTICLE PUBLICATION DATE
8-Jan-2024
The Frontiers of Knowledge Award goes to five European pioneers who discovered the link between greenhouse gases and rising global temperatures enclosed within the polar ice
The BBVA Foundation award in the Climate Change category has gone in this sixteenth edition to five European scientists for establishing a “fundamental coupling” between greenhouse gas concentrations and rising temperatures across the planet
Grant and Award AnnouncementIMAGE:
DORTHE DAHL-JENSEN, WINNER OF THE FRONTIERS OF KNOWLEDGE AWARD IN CLIMATE CHANGE.
view moreCREDIT: BBVA FOUNDATION
The BBVA Foundation Frontiers of Knowledge Award in the Climate Change category has gone in this sixteenth edition to five European scientists whose pioneering research on polar ice samples established a “fundamental coupling” between greenhouse gas concentrations and rising air temperatures across the planet over the past 800,000 years. The contributions of Denmark’s Dorthe Dahl-Jensen (University of Copenhagen), French scientists Jean Jouzel and Valérie Masson-Delmotte (Laboratoire des Sciences du Climat et de l’Environnement, Université Paris Saclay), and Swiss researchers Jakob Schwander and Thomas Stocker (University of Bern) have demonstrated that records extracted from Earth’s oldest and thickest ice deposits, in Antarctica and Greenland “show that changes in atmospheric concentrations of greenhouse gases, including carbon dioxide and methane, are accompanied by systematic changes in ambient air temperature across the globe.”
Their research on the natural variability of the Earth’s climate “contextualizes current greenhouse gas concentrations and the associated global warming” within the frame of planetary history, in the words of the award citation. For the committee, the convergent contributions of the five awardees have revealed that “over the past 800,000 years, greenhouse gas concentrations due to natural variability have never reached the atmospheric levels seen today,” the cause of our current human-induced global warming.
Their work, it concludes, “required scientific, technical and logical breakthroughs in many areas to measure greenhouse gas concentrations,” and “has built upon sustained international collaborative efforts by generations of researchers.”
“The main message from the ice sheets is that CO2 and temperature are tightly coupled; that the amount of greenhouse gases in the atmosphere today is without precedent in the last 800,000 years. And this has profound implications for how our planet will evolve over the coming decades and centuries,” says Bjorn Stevens, committee chair and Director of the Max Planck Institute for Meteorology. “If we want to abate or mitigate warming, it’s quite clear that we have to reduce the concentration of greenhouse gases in the atmosphere.”
“As it gradually accumulates, the snow that forms the polar ice captures the air around it,” explains committee member Miquel Canals, Director of the Sustainable Blue Economy Chair. “This air gets trapped in bubbles within the ice. And these bubbles are like a book on the atmospheric conditions prevailing through time which we need to decipher to get to their composition and meaning.”
The five awardee scientists have, in effect, reconstructed this precious record of the Earth’s climate conserved in the polar ice. “This is fascinating and invaluable work,” Canals continues, “which provides us with a benchmark for the current status of global warming.”
For Joan Grimalt Obrador, a researcher at the Institute of Environmental Assessment and Water Research (IDAEA) of the Spanish National Research Council (CSIC) and nominator of Thomas Stocker, the awardees’ principal achievement has been to demonstrate that today’s greenhouse gas concentrations are definitively off the scale. So we are on uncharted ground, living an experiment whose result is a question mark. And the threat is to human life, not nature, which has always found ways to adapt.”
Conclusive proof on the link between CO2 and warming
Ice core analysis has been a landmark in climate science, providing conclusive evidence of the linkage between greenhouse gases and the Earth’s temperature. Back in the 1960s, there were already physics-based climate models showing that increased atmospheric concentrations of carbon dioxide would lead to higher temperatures. What was missing was concrete data on the composition of the atmosphere through history that could validate this finding. Jean Jouzel’s analysis of an Antarctic ice core from the Vostok base, published in Nature in 1987, brought the needed confirmation: “The link between changes in greenhouse gases and temperature was really established thanks to that Vostok ice core,” he recalls today.
Although there had been studies done on ice cores, none had reached back further than the last ice age, which began 110,000 years ago. But the Soviet scientists stationed at Vostok managed to drill more than 2,000 meters down through the ice, obtaining samples of an age of up to 160,000 years, i.e., the previous interglacial period. Jouzel and his colleague Claude Lorius, who died in 2023, could get access to these samples thanks to the latter’s contacts with members of the Vostok team, and what the two observed was a close linkage between changes in the carbon cycle, atmospheric composition and climate, three key factors in the dynamics of glacial-interglacial cycles.
‘Time machines’ to establish the climate impact of human activity
Ten years after that Nature article, Valérie Masson-Delmotte elaborated on Jouzel’s work, extending his analysis to Greenland ice cores. Her conclusions matched those obtained by her compatriot at the opposite end of the planet, adding robustness to his findings. Since then, Masson-Delmotte and Jouzel, as well as their fellow awardees, have been working to refine the study of past climates and understand their evolution over hundreds of thousands of years.
“Ice cores are these amazing time machines,” Masson-Delmotte enthuses. “What is really striking is that we are finding ever stronger evidence confirming the intuition from the late 1970s.” And these records also highlight the extent to which atmospheric greenhouse gas levels have rocketed as a consequence of human activity: “The ice core record, together with other sources of information, shows that human influence on the whole climate system is unequivocal,” says the awardee scientist.
As well as modeling past climate with ice cores, Masson-Delmotte has combined this data with multiple other aspects of climate science to predict what the Antarctic will look like in 2070 under different warming scenarios. “We show that if global warming holds at levels close to present day, major changes could be avoided for the region, while with larger degrees of warming, there would be potentially irreversible changes.”
One implication of this warming would be a rise in sea level, which is already 20 centimeters higher than in 1900 and with the rate of increase accelerating since the 1990s. “We are heading for a sea-level rise of 50 cm by 2100 if warming is contained at low levels, and of more than one one meter in the event of very high greenhouse gas emissions,” Masson-Delmotte warns. “These rises will affect about one billion people by 2050, with multiple direct consequences for our coasts. In northern France, we have already experienced unmanageable flooding due to exceptionally high rainfall and rising sea levels.” In sum, the results achieved by this group of researchers show that the records preserved in the polar ice testify to phenomena and situations that extend across the whole planet, including the regions furthest from the poles.
Understanding Greenland’s past to understand the Earth’s future climate
Dorthe Dahl-Jansen’s contributions lie primarily in the reconstruction of past climate from the study of Greenland ice cores, as written up in a 1998 paper published in Science. “The knowledge from the past preserved in ice cores is important for understanding what can happen in the future,” she explains, “because most modeling work is based on instrumental records from weather stations that only reach 150 years back in time, a very stable climate period. And we know from the past that this is not the full story.”
“The ice gives us both temperature, through the analysis and interpretation of stable water isotopes, and greenhouse gas levels, through the air trapped inside,” Dahl-Jansen relates. Her research has found that past temperatures rose during periods of increased solar energy influx, which in turn increased CO2 in a positive feedback loop: “We know that when temperature rises, it warms the ocean, which releases CO2 into the atmosphere. These higher levels of CO2 warm the atmosphere and ocean even more, and then CO2 starts to rise again. So we get the warming episodes observed in the climate of the past.”
But what Dahl-Jansen’s research has revealed is that greenhouse gas concentrations at no point reached the levels of today. “Even though there have been previous warm periods, like we had 115,000 years ago, where the temperature was actually four degrees warmer, we never saw CO2 values higher than 300 parts per million, while the average today is 420 ppm. So it is us who have brought about these heightened values of CO2 that are driving up temperatures.”
This is why she is so concerned about the potential impacts of human-induced global warming, some of which are probably already unstoppable: “We know that CO2 stays in the atmosphere for more than 100 years, so it’s going to be very hard to stop temperatures rising with the greenhouse gas concentrations we have right now.” In fact, the Danish scientist believes some tipping points have already been passed, like the inevitable disintegration of the large Antarctic ice shelves that is visibly underway.
Dahl-Jansen also points out that, based on the results of her research on abrupt changes in past climate, there is a risk that the pouring of fresh water into the ocean, due to the ice melt, could disrupt the ocean currents that give Europe its relatively mild winters. “The Gulf Stream is important because it warms northern Europe, Denmark and Spain as well. And if it shuts down due to global warming, it will strongly impact climate in our countries, though ironically enough, it will cool the temperature.”
Technological innovation to trace climate history in the ice
None of this research would not have been possible without the technology to obtain ice cores, and here Jakob Schwander has been a pioneer. He refers to himself as “passionate” about engineering and ice drilling techniques. An area in which he is recognized as a brilliant innovator, developing, improving and creating new devices to reach ever deeper layers of pristine ice. This, precisely, has been one of his main contributions.
It was through his inventions that Schwander was able to analyze the air bubbles trapped in the “firn” – the layer of compacted ice at over 70 meters depth that lasts through winter after winter above the level of the glacial ice, and holds 25% of air. In 1984 he published a paper in Nature which concluded that the age of the air trapped in bubbles was significantly less than that of the enclosing ice.
“Thanks to the fact that heavy gases sink to the top layers of the firn, we can now tell the age of the air trapped in the polar ice layers, which do not coincide. This is a process that happens only in porous materials like firn or sand dunes. It doesn’t occur in the atmosphere because the atmosphere is constantly mixed by the wind. This has led to improvements in the construction of ice core age scales at different depths, which has also led to greater accuracy in measuring past temperature and precipitation,” he explains. “My contribution has maybe been to serve as a springboard for other studies. When I started, I was practically on my own. And now there are hundreds of people working on the subject.”
Just over ten years ago, Schwander began work on what would become his signature innovation, the world’s smallest ice drill, with a diameter of just 2 cm. Known as the RADIX (Rapid Access Drill for Ice eXtraction), in 2021 it reached a depth of 320 meters (-55º) in the Antarctic ice, a task completed in a few short days. “It’s a completely new technique, Schwander points out. “Many parts of the drill had to be redesigned to make them small enough.”
New models for a “unique knowledge” of our planet
Thomas Stocker, who worked with Schwander on the RADIX project, has measured concentrations of carbon dioxide trapped in the air bubbles of ice cores extending back 800,000 years. Seeking to interpret the data found, he developed a number of climate models to understand climate changes over a very long time scale spanning several ice ages.
He drew three main conclusions from this research. “First of all, carbon dioxide concentrations today are 35% higher than at any time in the past 800,000 years. Second, warming is without precedent in at least the last 2,000 years. And third, we have learned from polar ice cores that there are instabilities in the climate system, abrupt changes that could actually happen again in the future due to the large perturbations that man is inflicting on climate.”
The researcher insists that an important part of these findings is that they draw on data from both Antarctica and Greenland, providing “unique knowledge” about the dynamics of the Earth system. Abrupt changes in past climate indicate that the coupled system of the atmosphere and ocean have “limited stability” to perturbations, with the ocean being an important element in communicating large-scale climate disruptions between the hemispheres. Stocker points out that this had first been hypothesized based on model simulations, but “could then be confirmed by the precise analysis of ice cores from Greenland and Antarctica.”
The gap between the scientific evidence and political inaction in addressing the climate challenge
All five laureates believe there is a worrying gap between the unequivocal scientific evidence on the potential impacts of today’s climate change and the so far inadequate response of the international community. They also believe, however, that there remains room for maneuver in dealing with the challenge.
“We are still dragging our feet, although in most countries there is a growing awareness of the need to act,” Dahl-Jansen contends. “We have time, but if we wait, the consequences will be more severe, because greenhouse gases are still warming the planet and will continue to do so for the next 100 years, even if we halt emissions. So we need to react now and start reducing our use of fossil fuels.”
“For the moment it seems that we are not able to reach the goals we have set to tackle climate change,” says Schwander. “Probably because humans are not suffering enough yet. So I think to solve the problem we have to improve our energy efficiency and use of resources, and here we can learn a lot from nature. Nature is very efficient at using resources and recycling, and in the use of energy.”
“My impression is that the scientific community has done its work, in the sense that we have alerted policymakers to the gravity of the situation. But the real challenge is then to turn these recommendations into real and effective measures,” says Jouzel.
“It’s not about hope or despair,” adds Masson-Delmotte, “It’s a matter of effective action. When you find yourself with your back against the wall, when you are faced with extreme events like those experienced in Spain with fires, intense heat waves or heavy rainfall, what you need is not to resign yourself, but to step up the action.”
For Stocker “science identified the problem of climate change as early as the late 1970s, but the response of the public and the policymakers has been extremely slow. The time to act is now, and to act means to reduce greenhouse gas emissions as urgently as possible to keep within the temperature bands stated in the Paris Agreement of 2015, which means keeping global warming well within two degrees celsius. Inaction may mean short-term benefits but also long-term damages: conflicts between communities and between nations over resources like water and living space.”
Laureate bio notes
Dorthe Dahl-Jensen (Copenhagen, Denmark, 1958) received her PhD in Geophysics from the University of Copenhagen in 1988. She then took up a teaching and research position at this institution, with which she has remained associated throughout her career. Currently Villum Investigator Professor at the university’s Niels Bohr Institute, since 2018 she has also held a Canada Excellence Research Chair at the University of Manitoba (Canada). She led the Centre of Excellence for Ice and Climate at Copenhagen between 2007 and 2017, and has served as principal investigator on international programs ranging from deep drilling projects such as EastGRIP (East Greenland Ice-core Project) or NEEM (North Greenland Eemian Ice Drilling Project) to initiatives like Past4Future, funded by the European Union and involving 22 countries. She is also a researcher on the Green2Ice project, which in 2022 was awarded an ERC Synergy Grant worth 13.9 million euros.
Jean Jouzel (Janzé, Ille-et-Vilaine, France, 1947) obtained his engineering degree from the École Supérieure de Chimie Industrielle de Lyon (1968), going on to earn a PhD in Physical Sciences there in 1974. In 1973, he joined the French Alternative Energies and Atomic Energy Commission (CEA) as a research scientist. Today he is a CEA emeritus scientist at the Laboratoire des Sciences du Climat et de l’Environnement, a joint initiative of the CEA, the French National Center for Scientific Research (CNRS) and Université Paris-Saclay. Jouzel was a lead author on the second and third reports of the Intergovernmental Panel on Climate Change and served as vice-chair of its Working Group I. He is also a past director of the Institute Pierre-Simon Laplace, which brings together the expertise of eight laboratories, two associated teams and 1,500 professionals working in climate and environmental research. Jouzel is a Member Editor of the Proceedings of the National Academy of Sciences.
Valérie Masson-Delmotte (Nancy, France, 1971) obtained her engineering and master’s degrees at the École Centrale de Paris, where she also earned a PhD in 1996 with a thesis on past climate modeling. She is currently a senior scientist at the Laboratoire des Sciences du Climat et de l’Environnement (CEA, French National Center for Scientific Research [CNRS], Université Paris-Saclay), forming part of the Institute Pierre-Simon Laplace. Co-chair of Working Group I (Physical Science Basis) for the Sixth Assessment Report of the Intergovernmental Panel on Climate Change between 2015 and 2023, she has been listed as a Highly Cited Researcher in Geosciences (2014 to 2019) and in the Cross-Field category (2020 to 2022). Masson-Delmotte is a member of France’s High Council on Climate (HCC) and the French National Ethics Advisory Council.
Jakob Schwander (Koppigen, Switzerland, 1952) graduated in physics from the University of Bern and received his PhD degree from the same institution with a thesis on electrical conductivity measurements in Greenland and Antarctic ice samples for gas record studies. After completing postdoctoral research at the State University of New York at Buffalo, in 1986 he joined the Department of Climate and Environmental Physics at the University of Bern, where he is now a senior scientist at the Institute of Physics and the Oeschger Center for Climate Change. Schwander has participated in more than 20 expeditions to Greenland and Antarctica over the past 40 years. In this time, his drilling expertise has proved a powerful aid in international endeavors like the Greenland Ice Core Project (GRIP) or the European Project for Ice Sampling in Antarctica (EPICA).
Thomas Stocker (Zurich, Switzerland, 1959) graduated in physics from ETH Zurich, where he went on to receive a PhD in Natural Sciences in 1987. After holding a series of research positions at University College London, McGill University (Montreal) and Columbia University (New York), in 1993 he moved to the University of Bern, where he is now Professor of Climate and Environmental Physics in the Institute of Physics. Stocker has maintained a decades long association with the Intergovernmental Panel on Climate Change, as a coordinating lead author, then, between 2008 and 2015, as the co-chair of its Working Group I. It was during his tenure that the report Climate Change 2013: The Physical Science Basis was approved by governments, providing the scientific foundation for the Paris Agreement.
Nominators
A total of 67 nominations were received in this edition. The awardee researchers were nominated by Sune O. Rasmussen and Anders Svensson, University of Copenhagen (Denmark); James W. C. White, University of Colorado Boulder (United States); Philippe Bousquet, CEA Orme des Merisiers (French Alternative Energies and Atomic Energy Commission), France; Hubertus Fischer, Thomas F. Stocker and Nicolas Thomas, University of Bern (Switzerland) and Joan Grimalt Obrador, Spanish National Research Council (Spain)
Climate Change committee and evaluation support panel
The committee in this category was chaired by Bjorn Stevens, Director of the Max Planck Institute for Meteorology (Hamburg, Germany), with Carlos Duarte, holder of the Tarek Ahmed Juffali Research Chair in Red Sea Ecology at King Abdullah University of Science and Technology (Thuwal, Saudi Arabia), acting as secretary. Remaining members were Sandrine Bony, Director of Research in the Laboratoire de Météorologie Dynamique (LMD) at Sorbonne University (Paris, France); Miquel Canals, Director of the Sustainable Blue Economy Chair and and Professor of Marine Geosciences in the Department of Earth and Ocean Dynamics at the University of Barcelona (Spain); José Manuel Gutiérrez, Director of the Institute of Physics of Cantabria (IFCA) and Coordinating Lead Author of the Atlas chapter in the IPCC’s Sixth Assessment Report; Martin Heimann, Director Emeritus in the Department of Biogeochemical Systems at the Max Planck Institute for Biogeochemistry (Jena, Germany); Edward Rubin, Alumni Chair Professor of Environmental Engineering and Science Emeritus at Carnegie Mellon University (Pittsburgh, United States); Paul Wassmann, Professor Emeritus in the Department of Arctic and Marine Biology at UiT The Arctic University of Norway; and Julie Winkler, Professor of Geography in the Department of Geography, Environment and Spatial Sciences of Michigan State University (United States).
The evaluation support panel of the Spanish National Research Council (CSIC) was coordinated by Teresa Moreno Pérez, Deputy Coordinator of the LIFE Global Area and Research Professor at the Institute of Environmental Assessment and Water Research (IDAEA, CSIC), and formed by Josep M. Gasol Piqué, Research Professor at the Institute of Marine Sciences (ICM, CSIC), Guillermo Gea Izquierdo, Scientific Researcher at the National Institute for Agricultural and Food Research and Technology (INIA, CSIC); Francisca MartÃnez Ruiz, Scientific Researcher at the Andalusian Earth Sciences Institute (IACT, CSIC-UGR); and Sergio Vicente Serrano, Research Professor at the Pyrenean Institute of Ecology (IPE, CSIC).
About the BBVA Foundation Frontiers of Knowledge Awards
The BBVA Foundation centers its activity on the promotion of world-class scientific research and cultural creation, and the recognition of talent.
The BBVA Foundation Frontiers of Knowledge Awards, funded with 400,000 euros in each of their eight categories, recognize and reward contributions of singular impact in physics and chemistry, mathematics, biology and biomedicine, technology, environmental sciences (climate change, ecology and conservation biology), economics, social sciences, the humanities and music, privileging those that significantly enlarge the stock of knowledge in a discipline, open up new fields, or build bridges between disciplinary areas. The goal of the awards, established in 2008, is to celebrate and promote the value of knowledge as a public good without frontiers, the best instrument to take on the great global challenges of our time and expand the worldviews of each individual. Their eight categories address the knowledge map of the 21st century, from basic knowledge to fields devoted to understanding and interrelating the natural environment by way of closely connected domains such as biology and medicine or economics, information technologies, social sciences and the humanities, and the universal art of music.
The BBVA Foundation has been aided in the evaluation of nominees for the Frontiers Award in Climate Change by the Spanish National Research Council (CSIC), the country’s premier public research organization. CSIC appoints evaluation support panels made up of leading experts in the corresponding knowledge area, who are charged with undertaking an initial assessment of the candidates proposed by numerous institutions across the world, and drawing up a reasoned shortlist for the consideration of the award committees. CSIC is also responsible for designating each committee’s chair across the eight prize categories and participates in the selection of remaining members, helping to ensure objectivity in the recognition of innovation and scientific excellence.
Jean Jouzel, winner of the BBVA Foundation Frontiers of Knowledge Award in Climate Change.
CREDIT
Laboratoire des sciences du climat et de l'environnement.
Valérie Masson-Delmotte, winner of the BBVA Foundation Frontiers of Knowledge Award in Climate Change.
Jakob Schwander, winner of the BBVA Foundation Frontiers of Knowledge Award in Climate Change.
CREDIT
BBVA FOUNDATION
Thomas Stocker, winner of the BBVA Foundation Frontiers of Knowledge Award in Climate Change.
CREDIT
University of Bern.
Iron influences plant immunity and may promote resiliency against climate change
Salk researchers discover the molecule IMA1 links plant iron nutrition and immunity, providing a new potential target to help improve plant resilience
Peer-Reviewed PublicationIMAGE:
PLANT ROOT CROSS-SECTION SHOWING IRON DEFICIENCY SIGNAL IMA1 EXPRESSION (YELLOW) DURING IRON DEFICIENCY (LEFT) AND IRON DEFICIENCY PLUS SIMULATED BACTERIAL PRESENCE (RIGHT).
view moreCREDIT: SALK INSTITUTE
LA JOLLA (January 10, 2024)—Plants and animals alike rely on iron for growth and regulation of microbiomes—collections of bacteria, fungi, and more that co-exist in places like the human gut or the soil around a plant’s roots. Plants face a special challenge when acquiring iron, since the strategies plants use to increase iron availability alter the root microbiome and can inadvertently benefit harmful soil-dwelling bacteria.
Now, Salk scientists have discovered how plants manage iron deficiency without helping “bad” bacteria thrive—by eliminating IMA1, the molecular signal for iron deficiency in roots at risk of bacterial attack. Additionally, they found that more IMA1 in leaves can make them more resistant to bacterial attack, suggesting the iron deficiency signaling pathway and plant immune system are deeply intertwined.
The findings were published in Nature on January 10, 2024.
“There is a long-established relationship between plant iron nutrition and bacteria,” says senior author Wolfgang Busch, professor and executive director of Salk’s Harnessing Plants Initiative. “Exploring this relationship with more nuance allowed us to find a surprising new signaling pathway that plants use to turn off iron uptake as a defense strategy against threatening bacteria that also happens to alter the plant’s immune response.”
Because bioavailable iron (iron in a state that plants and animals can use) is a relatively scarce nutrient, iron deficiency—and consequential stunted plant growth—is not uncommon. Since stopping growth is not ideal, plants have developed techniques to encourage iron absorption in low-iron environments. Unfortunately, those techniques can alter the entire microbiome around the roots and increase iron availability for not just the plant, but for the harmful bacteria living nearby, too.
To unravel the complex relationship between plant health, iron levels, and bacterial threat, the researchers turned to a small model plant called Arabidopsis thaliana. They grew the plant in low-iron and high-iron growth substrate (soil), then added fragments of flagella (little tails bacteria use to move) to mimic the presence of bacteria.
"We hypothesized there would be some sort of competition between the plant and bacteria over the iron,” says first author Min Cao, a postdoctoral researcher in Busch’s lab. “But we found that when plants feel threatened by harmful bacteria, they are willing to stop acquiring iron and stop growing—they’ll deprive themselves in order to deprive the enemy.”
When roots were exposed to flagella in low-iron environments, the plants mounted an unexpected response: Rather than the expected battle over iron between plant and bacteria, the plant immediately forfeited by eliminating the iron-deficiency signal IMA1. When roots were exposed to flagella in high-iron environments, IMA1 was not eliminated, but did not need to be expressed since iron levels were sufficient.
In plants that eliminated IMA1 in response to low iron and flagella, the researchers encountered another surprise: The more IMA1, the more resistant plant leaves were to bacterial attack. This observation led to the conclusion that iron availability and iron deficiency signaling help orchestrate the plant immune response.
Busch believes IMA1 may be a useful target for optimizing plant immunity, which will become increasingly important as the planet’s climate continues to change and diseases begin to evolve more rapidly. Discovering that plants will halt iron uptake and arrest their growth in the face of potentially harmful bacteria is the beginning of a much longer story about plant resilience, plant and animal microbiomes, and climate change.
“Microbes determine the fate of carbon in soil, so uncovering how plants react to and impact their soil microenvironment can teach us a lot about optimizing plant carbon storage,” says Busch, who is also the Hess Chair in Plant Science at Salk. “Relatedly, understanding how plants regulate signaling and immune responses in the face of environmental scarcities, like iron deficiencies, will be crucial as scientists optimize plant health in our continually changing climate.”
In the future, the researchers will explore whether targeting IMA1 can change plant resistance to disease, and how exactly the individual cells in plant roots shut down the IMA1 signaling pathway. Learning about plant roots can teach scientists about other absorptive tissues, like the human gut, so they can better understand the intersection of mammalian microbiomes, immune systems, and iron to optimize health.
Other authors include Matthieu Pierre Platre, Ling Zhang, Tatsuya Nobori, Yingtong Chen, Wenrong He, Lukas Brent, and Joseph Ecker of Salk; Huei-Hsuan Tsai and Niko Gelder of the University of Lausanne; and Laia Armengot and Nuria Coll of the Centre for Research in Agricultural Genomics in Bellaterra, Spain.
The work was supported by the National Institutes of Health (R01GM127759, NCI CCSG: P30 014195), the Human Frontier Science Program (LT000661/2020-L), the Chapman Foundation, the Helmsley Charitable Trust, de Ministerio de Universidades, the European Union, the Ministerio de Ciencia e Innovación and Agencia Estatal de Investigació (PID2019-108595RB-I00, 10.13039/501100011033, TED2021-1311457B-I00), Taiwan’s Ministry of Science and Technology (111-2917-I-564-021), and the Centres de Recerca de Catalunya.
Plant root (gray) showing IMA1 expression (yellow) during iron deficiency (left) and iron deficiency plus simulated bacterial presence (right).
CREDIT
Salk Institute
About the Salk Institute for Biological Studies:
Unlocking the secrets of life itself is the driving force behind the Salk Institute. Our team of world-class, award-winning scientists pushes the boundaries of knowledge in areas such as neuroscience, cancer research, aging, immunobiology, plant biology, computational biology, and more. Founded by Jonas Salk, developer of the first safe and effective polio vaccine, the Institute is an independent, nonprofit research organization and architectural landmark: small by choice, intimate by nature, and fearless in the face of any challenge. Learn more at www.salk.edu.
JOURNAL
Nature
ARTICLE TITLE
Spatial IMA regulation restricts root iron acquisition upon MAMP perception
Record heat in 2023 worsened global droughts, floods and wildfires
IMAGE:
CONDOR CREEK IN THE URIARRA FOREST, ACT. PHOTO: LANNON HARLEY/ANU.
view moreCREDIT: CREDIT: LANNON HARLEY/ANU.
Record heat across the world profoundly impacted the global water cycle in 2023, contributing to severe storms, floods, megadroughts and bushfires, new research from The Australian National University (ANU) shows.
The findings are outlined in a new report released today by the Global Water Monitor Consortium and led by ANU researchers.
Lead author Professor Albert Van Dijk, from ANU, said the report underscores the consequences of persistent fossil fuel burning on natural disasters, water resources, biodiversity and food security.
“Record-breaking heat waves swept across the globe in 2023, shattering previous records, from Canada to Brazil and from Spain to Thailand,” Professor Van Dijk said.
“The lack of rainfall and high temperatures exacerbated multi-year droughts in South America, the Horn of Africa and around the Mediterranean.
“Extremely hot and dry conditions inflicted extensive ecological damage on the world's largest forests. Massive wildfires ravaged Canada during the northern summer, while the Amazon rainforest and rivers rapidly descended into severe drought in late 2023.”
Some of the worst disasters of 2023 were linked to unusually strong cyclones bringing extreme rainfall to New Zealand, Mozambique and Malawi, Myanmar, Greece, Libya and Australia.
According to Professor van Dijk, who is also Chair of the Global Water Monitor Consortium, rising sea surface and air temperatures caused by fossil fuel burning have been intensifying the strength and rainfall intensity of monsoons, cyclones and other storm systems.
This was also evident closer to home, where Cyclone Jasper battered northern Queensland and severe storms hit southeast Queensland.
“Some areas around Cairns recorded more than 800 millimetres of rain. The torrential rains caused widespread flooding. That was because the cyclone moved much slower than expected,” he said.
“The recent cyclones and intensive storms in Queensland and elsewhere in Australia should not be seen as isolated freak events but part of a global pattern that was quite clear in 2023.
“In 2023, we saw cyclones behave in unexpected and deadly ways. The longest-lived cyclone ever recorded battered southeastern Africa for weeks.
“Warmer sea temperatures fuelled those freak behaviours, and we can expect to see more of these extreme events going forward.”
Professor van Dijk said the last two decades have seen increased air temperatures and declining air humidity, causing increased heat stress and water requirements for people, crops and ecosystems, while intensifying droughts.
Relative air humidity over the global land surface in 2023 was the second driest on record after 2021, continuing a trend towards drier and more extreme conditions. 2023 was Earth’s hottest year on record, showing what a typical future year with 1.5 degrees warming may look like.
“A total of 77 countries experienced the highest average annual temperature in at least 45 years,” Professor Van Dijk said.
Professor Van Dijk said 2023 was a year of extremes, with increasing extreme dry and wet conditions and more unprecedented weather events. This is in line with ongoing changes in the water cycle over the last two decades.
“The events of 2023 show how ongoing climate change is threatening our planet and lives more with every passing year,” he said.
“Globally, we’re seeing an increase in the frequency and intensity of rainfall events and river flooding. But at the same time, there are also more frequent and faster developing droughts, or ‘flash droughts’.
“That can cause crop failure and destructive wildfires in a matter of weeks or months. With the global food challenge, biodiversity crisis and an extremely urgent need to reduce carbon emissions, these droughts and wildfires are among our greatest global threats.”
The research team used data from thousands of ground stations and satellites orbiting the Earth to provide real-time information on rainfall, air temperature, air humidity, soil and groundwater conditions, vegetation, river flows, flooding, and lake volumes.
The Global Water Monitor is a collaboration between institutions across the world and involves various public and private organisations.
The 2023 report is available on the Global Water Monitor website.
METHOD OF RESEARCH
Data/statistical analysis
