( Minnesota Reformer) – The Biden administration plans to distribute more than $3 billion to fund projects that will reduce greenhouse gas emissions and sequester carbon in agriculture and forestry — a tripling of its initial commitment in February.

U.S. Secretary of Agriculture Tom Vilsack was set to publicly announce the expansion of the Partnerships for Climate-Smart Commodities program on Wednesday, along with 70 projects that will receive the initial funding.

“This is a really, really important day for American agriculture,” Vilsack told reporters Tuesday. “I just hope everybody fully appreciates the significance of what we’re doing here.”

U.S. Secretary of Agriculture Tom Vilsack said more than $3 billion will fund greener agricultural practices. Photo by Jared Strong/Iowa Capital Dispatch.

The program is being funded through the Commodity Credit Corporation, which has been historically used to support farmers with loans and payments and to fund conservation programs of the farm bill.

The U.S. Department of Agriculture has said it can use the CCC to fund the new climate program without congressional approval because it will “aid in the expansion of markets for agricultural commodities,” a provision of its charter. A key goal of the program is to create markets for climate-friendly products.

“We have significant resources left in the CCC account to be able to adequately and fully and completely respond to any farm bill program payments,” Vilsack said.

The initial selected projects will get a total of about $2.8 billion over the course of five years, and the companies, universities, conservation groups and others that have proposed them will contribute a total of about $1.4 billion, Vilsack said. Funding for a second group of projects is expected later this year.

It’s part of a voluntary approach the Biden administration is taking toward its goal of “net zero” agriculture that would boost the amount of carbon that remains in soil and reduce the emissions of livestock, machinery and other sources. Rather than force farmers to reduce emissions and improve soil health through regulations, Vilsack hopes to give farmers lucrative markets for products that are the result of those reduced-emissions strategies.

The initial round of projects is expected to encompass the production of livestock, milk, corn, soybeans, wheat, rice, peanuts, cotton, timber and others, with producers in each state included in at least one project. The program requires that those project leaders make periodic reports of their progress.

“This will be a very transparent process,” Vilsack said. “We will be reporting on it on a regular basis.”

At least 15 of the 70 projects will include Iowa producers, according to project summaries provided by USDA. Up to $95 million will go to an Iowa Soybean Association program that pays farmers to implement conservation practices to keep more carbon in the soil and improve water quality. The greenhouse gas reductions can be sold to companies and organizations who seek to offset their own emissions.

Agriculture accounts for about 11% of greenhouse gas emissions in the United States, according to the U.S. Environmental Protection Agency.

This story was originally published by Iowa Capital Dispatch, a States Newsroom outlet and sister-site of the Minnesota Reformer.

( Cronkite News) – PHOENIX – As a climate change activist and mental health advocate, Saiarchana Darira studies the effects of global warming not just on the environment but on the well-being of people worldwide.

The recent Arizona State University graduate and self-described “environ(mental) health researcher” works as the youth engagement lead at Turn It Around!, a project enlisting young people across the globe to help educate adults about the dangers of climate change.

Toddlers, teens and young adults from Canada to India have designed flashcards – with artwork on one side and short essays or comments about the effects of climate change on the other – to challenge people to “think, see and act in new ways.”

“Climate injustice is a very complex and widespread issue, and how it affects mental health is overlooked,” Darira said, pointing to Arizona’s often record-breaking, blazing temperatures as one example.

“The lack of being able to go outside due to the heat, the increase in feelings of isolation, ecological grief – they all play a role in mental health.”

Turn It Around! enlists young people to design flashcards about climate change. This card, by two teens from India, encourages people to “think about sustainability through the lens of environmental health.” (Photo courtesy of Turn It Around!).

During an annual meeting of its delegates in June, the American Medical Association declared climate change a public health crisis and said it would push for more policies to help limit global warming to no more than 1.5 degrees Celsius – the ceiling included in the Paris climate accord.

The organization highlighted the health risks of producing fossil fuel-derived hydrogen and said it will develop plans to help physicians adopt environmentally sustainable programs in their practices.

“Our patients are already facing adverse health effects associated with climate change – from heat-related injuries, vector-borne diseases and air pollution from wildfires to worsening seasonal allergies and storm-related illness and injuries,” AMA board member Ilse Levin said in a statement.

“Taking action now won’t reverse all of the harm done, but it will help prevent further damage to our planet and our patients’ health and well-being.”

From 2030 to 2050, according to the World Health Organization, 250,000 additional deaths are expected each year worldwide because of climate-driven health problems, including malnutrition, malaria and heat.

In Arizona, health conditions related to rising temperatures are a primary concern.

Even before the official start of summer this year, Phoenix hit a high of 114 degrees. As of July 23, Maricopa County – Arizona’s most populous – had seen 38 confirmed heat-associated deaths for the year, more than the 26 recorded over the same time period in 2021.

Over all of last year, the county recorded 339 heat-associated deaths – the highest on record.

(Graphic from Maricopa County)

Decades of rising temperatures prompted Phoenix to allocate almost $3 million to heat readiness in its 2021-22 budget, to launch an Office of Heat Response & Mitigation last fall, and to develop a heat response plan.

“We’ve certainly seen significant trends in temperature here in Arizona, especially nighttime temperatures, as a consequence of urbanization and global scale climate change,” said David Hondula, director of the city’s Office of Heat Response & Mitigation. “Those increases, particularly in our summer months, can have adverse impacts on public health.”

A new Phoenix shelter can provide relief for up to 200 people experiencing homelessness. “Almost everyone that comes in our doors initially has some level of heat-related illness,” says Jennifer Morgan, program director. (Photo by Troy Hill/Cronkite News)

Efforts in the works to address the problem include increasing tree and canopy shade by 25%; continuation of the city’s Cool Pavement Program, a project that applies an asphalt seal coating to combat the urban heat island effect; and a new heat shelter in Phoenix that can provide relief for up to 200 people experiencing homelessness.

“Almost everyone that comes in our doors initially has some level of heat-related illness, whether it be dehydration or extreme sunburn or signs of heatstroke,” said Jennifer Morgan, program director of the new shelter. “The need for a program like this one has existed, but the urgency was created by the heat.”

Heat affects the body in many ways: dehydration, heat stroke, exhaustion and anxiety, while also compromising preexisting heart and lung conditions.

An editorial in the New England Journal of Medicine, written by leaders of medical journals worldwide, cites a host of other issues: “dermatological malignancies, tropical infections, adverse mental health outcomes, pregnancy complications, allergies and cardiovascular and pulmonary morbidity and mortality.”

The authors note that vulnerable populations are those most at-risk: children, older people, individuals of color, the poor and those with underlying health problems.

Black people are 40% to 59% more likely to live in high-impact areas – those that experience the most brutal effects of climate change first.

Indigenous communities face a unique struggle with climate change. Living in tribal and rural areas along the coast leaves them vulnerable to the heat, and many rely on the environment for food and cultural practices.

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Heat has a new enemy in Phoenix: A city office dedicated to fighting rising temperatures

In Arizona, the White Mountain Apache Tribe and other tribal communities are facing water shortages, with heat and drought only exacerbating the problem.

“As we look into a warmer future,” Hondula said, “we need to be mindful of our currently constrained water resources.”

Concerns about the impact of the climate crisis on health are driving doctors, nurses, medical students and others to become advocates for change.

The Medical Society Consortium on Climate and Health, which amplifies the voices of doctors in the U.S. while encouraging climate solutions, developed a three-prong approach to the issue: Stop investing in energy produced by fossil fuels, do invest in and support renewable energy, and make the transition fair to everyone.

“Now is the time to ‘go big’ to meet the needs of the moment,” the group said in a 2022 report on climate and health. “We can and must raise our voices to influence the decisions that will affect health now and for generations to come.”

Last year, Darira’s group presented its flashcard initiative at the U.N. Climate Change Conference in Glasgow, Scotland, with the hope of influencing politicians, policymakers and educators to do more.

“The atmosphere is warming at a very alarming rate, and the world leaders are not taking urgent enough action,” Darira said.

Alexandra Conforti, Health Reporter, Phoenix, expects to graduate in May 2022 with a bachelor’s degree in journalism and a minor in criminology and criminal justice. Conforti has interned at Times Media Group in Phoenix, and has experience with photo and social media.

Troy Hill, News Visual Journalist, Phoenix, graduated in May 2022 with a bachelor’s degree in journalism and a minor in film production. Hill worked for the ASU Lodestar Center for Philanthropy and Nonprofit Innovation and is working for the Phoenix news bureau.

Via Cronkite News

Southern Tasmania’s tall eucalyptus forests are exceptionally good at taking carbon dioxide from the atmosphere and converting it into wood.

For many years, we have believed these forests had a reasonable buffer of safety from climate change, due to the cool, moist environment.

Unfortunately, my research published today shows these forests are closer to the edge than we had hoped. I found during heatwaves, these forests switch from taking in carbon to pumping it back out.

That’s not good news, given heatwaves are only expected to increase as the world heats up. While we work to slash emissions, we need to explore ways to make these vital forests more resilient.

From carbon dioxide in to carbon out

It’s well established from forest sampling that moist, cool environments like southern Tasmania provide ideal growing conditions for tall eucalypt forests.

We had believed these types of forests would have a buffer against the worst effects of climate change to come, and perhaps even benefit from limited warming.

But this is no longer the case.

I monitored what happened to a messmate stringybark (Eucalyptus obliqua) forest during a three week heatwave in November 2017. Under these conditions, the forest became a net source of carbon dioxide, with each hectare releasing close to 10 tonnes of the greenhouse gas over that period.

A year earlier during more normal conditions, the forest was a net sink for carbon dioxide, taking in around 3.5 tonnes per hectare.

How can we know this? The forest I studied is at the Warra Supersite in the upper reaches of the Huon Valley, one of 16 intensive ecosystem monitoring field stations making up Australia’s Terrestrial Ecosystem Research Network.

Instruments mounted on an 80-metre-tall tower at Warra give us great insight into how the forest is behaving. We can measure how much, and how quickly, carbon dioxide, water and energy shuttle between the forest and the atmosphere.

So what actually happened in the forest during the hot spell? Two crucial things.

The first was that the forest breathed out more carbon dioxide. This was expected, because living cells in all air-breathing lifeforms (yes, this includes trees)
respire more as temperatures warm.

But the second was very unexpected. The forest’s ability to photosynthesise fell, meaning less solar energy was converted to sugars. This took place while the trees were transpiring (releasing water vapour) rapidly.

Until now, we’ve seen falls in photosynthesis output in heatwaves because the trees are trying to limit their water loss. They can do this by closing their pores on their leaves (stomata). When a tree closes its stomata, it makes it harder for carbon dioxide in air to enter the leaves and fuel the photosynthesis process.

By contrast, this heatwave saw trees releasing water and producing less food at the same time.

So what’s going on? In short, the temperatures were simply too hot for the forests in southern Tasmania. Every forest has an ideal temperature to get the best results from photosynthesis. We now know this temperature in Australia is linked to the historic climate of the local area.

That means the trees at Warra require lower temperatures to optimally feed themselves, compared to most other Australian forests.

During the 2017 heatwave, the temperatures soared well outside the forest’s comfort zone. In the hottest part of the day, the forest was no longer able to make enough food to feed itself.

Outside the forest’s comfort zone

For now, the forest at Warra is still intact. After the heatwave, the messmate stringybark forest quickly recovered its ability to feed itself, and became a carbon sink again.

But as the world warms, these forests will be pushed outside their comfort zones more and more. They can only endure so many of these kinds of heatwaves. If they keep coming, there will be a tipping point beyond which the forest can no longer recover.

What then? We can see a disturbing glimpse when we look at Tasmania’s oceans, which are a marine heatwave hotspot. Fully 95% of Tasmania’s giant kelp forests are now gone, killed off by temperatures beyond their ability to tolerate.

It is no exaggeration to say that the rapid increase in temperatures are the most serious threat to the health of tall eucalypt forests I’ve encountered during 40 years of studying forest health and threats in Tasmania.

Unlike the kelp forests, our tall eucalyptus forests have not yet hit their tipping point. We still have time to lessen the risk global heating poses.

There is already work under way to test promising new methods for making future forests better able to cope with the new climate they find themselves in.

These techniques include climate adjusted provenancing, where forest managers sow seeds of local species collected from areas at the hotter end of their range. Another being tried for giant kelp is finding individual plants with better heat tolerance and breeding them.

Our eucalyptus forests will need our help, more and more. The better engaged and informed we are about the risks to forests we long thought were highly resilient, the likelier we will be to be able to preserve them.

One way we could do this is by making our monitoring data publicly accessible in real time, so we can grasp the strain our forests are under as the world warms.

Tim Wardlaw, Research Associate, University of Tasmania

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

When it comes to climate change, no nation is more important than China. It consumes more coal than the rest of the world combined, and it is the leading emitter of greenhouse gases, accounting for nearly 30% of global emissions.

Unless China takes rapid steps to control its greenhouse gas emissions, there is no plausible path to achieving the Paris climate agreement aim to limit global warming to 1.5 degrees Celsius (2.7 F), or even the less ambitious target of “well below 2 C” (3.6 F).

So, with the Olympic spotlight on China, what is the country doing to help the world avoid the worst impacts of climate change, and is it doing enough?

China’s record is mixed. Over the past year, China has signaled that it intends to continue on its well-worn path of making modest, incremental contributions to combat climate change, an approach inadequate for achieving the Paris goals. Yet, as an expert in environmental diplomacy who has followed China’s actions for years, I see reasons to think China might increase its efforts in the coming years.

China’s measured approach to climate change

A common misconception is that China either lacks climate policies or fails to implement them. The reality is that China has a robust set of climate and energy policies and a strong track record when it comes to fulfilling its pledges to the international community.

Driven by a desire to reduce air pollution, enhance energy security and dominate the industries of the future, China has been the world’s leading investor in renewable energy since 2013, and it has been buying up raw materials those industries need, such as cobalt mines in Africa. It has three times more renewable energy capacity than any other country, and its electric vehicle use is growing. As of 2019, about half the world’s electric vehicles and 98% of electric buses were in China.

Overall, China achieved nine of the 15 quantitative targets in its 2015 climate commitments ahead of schedule. Over the past decade, coal has fallen from about 70% to 57% of its energy consumption.

In September 2021, Chinese President Xi Jinping indicated that China will stop financing overseas coal power plants. This is likely to lead to the cancellation of much of the 65 gigawatts of coal power plants it had planned in Asia, roughly three times the annual emissions of Bangladesh. And unlike the U.S., China has also established a national emissions trading system for the electricity sector, though it lacks a hard cap on emissions.

When it comes to China’s approach to climate change, the problem is not a lack of policy implementation but rather a lack of policy ambition. China’s climate policies are admirable for a middle-income country that only recently escaped the ranks of the poor, but, like most of the world’s nations, it is still not doing enough.

This is evident both in China’s revised commitments presented at the U.N. climate summit in Glasgow in November 2021 and in its current Five-Year Plan (2021-2025). Both represent piecemeal improvements but will make it difficult to keep global warming well below 2 C.

For instance, China aims to have its carbon dioxide emissions peak before 2030 and be carbon neutral by 2060. These soft targets reflect a Chinese tendency in international negotiations to underpromise so that it can overdeliver. To be consistent with the Paris Agreement aims, China will need to set a cap on emissions and move forward its peak dates.

Current policy and recent history have also raised concerns that China’s coal use will not decline fast enough over the 2020s to achieve the 1.5 C target.

Three times in the past four years China responded to either an energy shortage or economic slowdown by allowing coal production and consumption to surge. In 2020, it added almost 40 gigawatts of new coal capacity, roughly equal to the entire coal fleet of Germany, the world’s fourth-largest industrial power.

Reasons for cautious optimism

There is still a chance that China will enhance its contribution to the fight against climate change.

It is worth noting that China is still developing the policies that will guide its approach to climate change over the next decade. It has released two overarching documents for reaching carbon neutrality and an emissions peak in 2030. Over the next year or so, it intends to release 30 sector- and province-specific documents to guide industries such as steel, cement and transportation.

Two key developments at Glasgow could also nudge China to do more.

First, a considerable number of countries increased their climate pledges, which ratchets up pressure on China.

More than 100 nations pledged to cut emissions of methane, a highly potent greenhouse gas, by 30% by 2030. India pledged to reach net-zero carbon emissions by 2070 and, more importantly, indicated it would potentially get half its electricity from renewable sources by 2030. There were also multicountry pledges to end deforestation, phase out coal and cut international funding for fossil fuels.

Like any country, China’s climate actions are driven primarily by domestic political considerations. However, over the past three decades Chinese policy has responded to – and been shaped by – external forces including diplomacy, advocacy and scientific exchange.

Developing countries, in particular, can influence China’s approach to climate change. Because China has long positioned itself as a leader of the developing world and is sensitive to its international image, it can be hard for Beijing to resist pressure from other developing countries. The fact that several countries, such as India, Indonesia and Vietnam, made bolder-than-expected pledges at Glasgow could induce Beijing to offer more aggressive targets for controlling emissions.

The second key development is that the United States and China achieved a much-needed thaw in their relationship at Glasgow and laid a foundation for future cooperation.

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Although there is some debate about whether the climate benefits more from Sino-American competition or cooperation, there was concern that hostility between China and the U.S. could derail the talks.

Therefore, it was a welcome relief when late in the summit China and the U.S., the second largest greenhouse gas emitter, released a joint declaration outlining their shared commitment to combating climate change.

They agreed to establish a “working group on enhancing climate action in the 2020s” and to meet early in 2022 to address methane emissions. China also indicated it would release a national action plan for methane. This is significant because China did not sign the Global Methane Pledge and has not traditionally included noncarbon greenhouse gases – about 18% of China’s total emissions – in its commitments.

Will developing country pressure and U.S.-China cooperation be enough to persuade China to take more aggressive action? Only time will tell, but Glasgow may have been the crossroad where China and the rest of the world chose a more sustainable path.

This article was updated with attention on China’s climate record during the Olympics.

Phillip Stalley, Endowed Professor of Environmental Diplomacy & Associate Professor of Political Science, DePaul University

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

In October 2019, I set sail with a team of scientists aboard the Canadian Coast Guard Vessel John P. Tully in the northeast Pacific Ocean, off the coast of Vancouver Island. Battling rough seas and lack of sleep, we spent the better part of a week working shoulder-to-shoulder in a small stand-up refrigerator, analyzing seafloor sediments to learn more about the effects of low-oxygen conditions on deep-sea environments.

When organisms die, they sink through the water column, consuming oxygen in the sub-surface ocean as they decompose. This leads to bands of oxygen-depleted water called oxygen minimum zones, or “dead zones.”

These harsh environments are uninhabitable for most organisms. Although they occur naturally in some areas, dead zones often appear after fertilizer and sewage wash downstream into coastal areas, sparking algal blooms, which then die off and decompose.

One of our studies from that expedition suggested that the sediments below oxygen-depleted waters are a significant source of nitrous oxide (N2O). This gas is released into the atmosphere when deep water rises to the surface in a process known as upwelling.

Nitrous oxide, more commonly known as “laughing gas,” is a potent greenhouse gas, 300 times more powerful than carbon dioxide. Global emissions of N2O are increasing as a result of human activities that stimulate its production.

N2O hotspots

The oceans currently account for around 25 per cent of global N2O emissions, and scientists are working to improve estimates of marine contributions. Most research has focused on oxygen minimum zones, which are known as hotspots of N2O emissions.

Warming of the ocean due to climate change is driving the expansion of marine oxygen minimum zones globally. This has led to speculation that N2O emissions from the oceans will continue to increase and further accelerate climate change. Our results indicate that even more N2O production may be expected where these low-oxygen waters are in contact with the seafloor.

This story is part of Oceans 21

Our series on the global ocean opened with five in-depth profiles. Look out for new articles on the state of our oceans in the lead up to the UN’s next climate conference, COP26. The series is brought to you by The Conversation’s international network.

Nitrogen is an essential component to life on Earth and exists in the environment in many different forms. Specialized groups of single-celled microbes use nitrogen-containing compounds, such as ammonium and nitrate, for energy to drive cellular functions. These metabolic reactions mediate the transformation of nitrogen between its various states in the environment, during which N2O can leak out into the environment as a byproduct.

Aside from its effects as a greenhouse gas, N2O is also the predominant ozone-depleting substance emitted to the atmosphere.

Mangroves as N2O banks

Our team travelled to Bermuda in the fall of 2020 to measure N2O emissions in a pristine mangrove forest in collaboration with the Bermuda Institute of Ocean Sciences. These sediments were shallower and accessible to snorkelers, which allowed us to thoroughly investigate their role in N2O cycling under different environmental conditions.

We found the seabed sediments in the Bermuda mangroves were actually consuming N2O from the overlying seawater. Similar N2O “sinks” have been described previously in other pristine systems, including estuaries, mangroves and even terrestrial soils.

The ability of these areas to draw N2O from the atmosphere is tied to the concentrations of nitrogen-containing nutrients in the environment. Nitrous oxide production is inhibited when these nitrogen-containing nutrients are in short supply. When nutrient levels are sufficiently low, marine habitats can act as net consumers of N2O.

Sediments that act as N2O sinks can also act as net sources of N2O to the atmosphere when subjected to increased nitrogen loading from agricultural runoff and urban waste water. Indeed, mangroves and other near-shore ecosystems that experience sustained inputs of dissolved nitrogen tend to be large N2O emitters.

The extent to which pristine environments can serve as buffers against increases in atmospheric N2O concentrations is still uncertain. Most studies to date have focused on densely populated and highly disturbed regions of Europe and Asia, which act as sources of N2O. This leaves much to be learned about the role of pristine marine habitats as N2O sinks and their overall influence on global N2O budgets.

Targeting fertilizer

Although reducing future marine N2O emissions hinges on the more complex problem of slowing the growth and spread of marine oxygen minimum zones, actions to conserve and restore pristine coastal environments are tractable interventions that can be implemented in the short term.

At present, human agricultural practices account for over two-thirds of global N2O emissions. As a result, much attention has been directed at reducing the amount of excess nitrogen added to agricultural soils via fertilizer. Since nutrients that are not taken up by plants often end up in watersheds that drain into the ocean, policies that address overuse of fertilizers will also benefit adjacent aquatic ecosystems.

However, further reducing marine emissions will require a multifaceted approach that also addresses coastal development and waste-water disposal practices in heavily impacted areas.

The United Nations has declared 2021 as the start of a Decade of Ocean Science for Sustainable Development. Detailing the vital link between oceans and climate change has never been more timely than now.

Brett Jameson, PhD Candidate in Biological Oceanography , University of Victoria

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

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Bonus Video added by Informed Comment:

UCTV: “Oceans Out of Breath: Oxygen Minimum Zones in a Warming Climate”

As the world warms and the atmosphere becomes increasingly fertilised with carbon dioxide, trees are growing ever faster. But they’re also dying younger – and overall, the world’s forests may be losing their ability to store carbon. That’s the key finding of our new study, published in the journal Nature Communications.

In a world without humans, forests would exist in equilibrium, taking roughly as much carbon out of the atmosphere as they lose. However, humans have disturbed this equilibrium by burning fossil fuels. As a result, atmospheric CO₂ levels have increased leading to an increase in temperature and fertilising plant growth. These changes have stimulated tree growth over the past decades, even in intact, “old-growth” forests that have not experienced recent human disturbances. This in turn has allowed forests to take up more carbon than they release resulting in large net accumulation – what’s often called the “carbon sink”.

Earth scientists like us often wonder how long forests can continue to be a sink. The extra CO₂ will benefit trees everywhere, and temperature increases will help them grow in colder regions. So you could expect forests to continue soaking up much of our carbon emissions – and that is exactly what most earth system models predict.

However, possible changes in tree lifespan may throw a spanner in the works. A few years back when studying old-growth Amazon forests, we noted that initial growth increases were followed by increases in tree mortality. We hypothesised that this could be due to faster growth reducing how long trees live for. If true, this means predictions that the carbon sink will continue may have been overly optimistic, as they did not take into account the trade-offs between growth and longevity. Our new findings provide evidence for this hypothesis.

To study the relationship between tree growth and longevity, we used tree ring records. The width of each ring tells us how fast the tree grew, while counting rings provides information on age and allows us to estimate its maximum lifespan. We analysed more than 210,000 individual tree ring records belonging to more than 80 different species from across the globe. This large undertaking has been possible thanks to decades of work by dendrochronologists (tree ring specialists) from across the world, who made their data publicly available.

The hare and the tortoise

Our analysis shows that trees that grow fast, die young. It has been known for a long time that faster growing species live shorter. A balsa tree, for example, grows quickly to 20 metres or more but will live for only a few decades, while some bristlecone pine trees have been growing slowly and steadily for nearly 5,000 years.

We found that this is not only true when comparing different species, but also within trees of the same species. It was a surprise to find that this trade-off occurs in nearly all types of trees and ecosystems, from closed-canopy tropical forests to the hardy trees that brave the Arctic regions. A slow growing beech tree may be expected to live several decades longer than its fast-growing relatives. It is very much like the story of the hare and the tortoise – slow but steadily growing trees are the ones that live longest.

In order to study the implications of this we compared how much carbon would be accumulated under two tree simulation models. One simulation included this “grow-fast, die-young” trade-off, and the other used a model in which trees lived equally long, regardless of their growth rates. We found that trees growing faster and dying younger initially caused the overall level of biomass to increase, but it also increased tree mortality several decades later.

Therefore, eventually the forest starts to lose biomass again and return to the same level as in the beginning, but with faster growing and shorter-lived trees. Our models indicate that faster growth results in faster tree death, without real long-term increases in carbon storage. Some researchers predicted this long ago, and our results support their prediction.

These model predictions are not only consistent with observed changes in forests dynamics in the Amazon but also with a recent study reporting an increase in tree death across the globe.

Why do rock stars die young?

An intriguing question is why the fast-growing trees, the “rock stars” of the forest, live much shorter lives. We don’t yet have a conclusive answer, but we have looked at some potential mechanisms. For example, it could be that higher temperatures and other environmental variations that stimulate faster growth, also reduce tree lifespans. However, we find that reductions in lifespan are the result of faster growth itself.

One simple hypothesis is that trees die once they reach a certain maximum potential size, and the faster a tree reaches this size the younger it dies. Other possible explanations are that fast growing trees simply make cheaper wood (in terms of energy expenditure), and invest fewer resources in fighting off diseases and insect attacks, or are more vulnerable to drought. Whatever the cause, this mechanism needs to be built into scientific models if we want to make realistic predictions of the future carbon sink and thus how much CO₂ will be in the atmosphere.

Roel Brienen, NERC Research Fellow, University of Leeds and Emanuel Gloor, Professor in Biogeochemical Cycles, University of Leeds

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

One of the first things I teach students is the difference between energy and electricity. Electricity is a particular form of energy, but often the two words are used interchangeably.

Britain recently celebrated its longest streak without burning coal to generate electricity. For the first quarter of 2020, global electricity demand fell by 2.5%, while at the same time, demand for coal and oil fell by 8% and 5% respectively. Renewable electricity was the only source to see demand growth in big markets over this same period, growing by 8% compared to 2019 in the EU and UK.

This all sounds like good news, and it is. But in the grand scheme of things, generating less carbon-rich electricity might not be that big a deal in the fight against climate change. That’s because the electricity sector makes up just 17% of the total energy the world uses in 2020. Almost a quarter of that electricity is supplied by renewables. So what about the rest of our energy needs?

Transport and heating

Transport amounts to 32% of global total energy demand, but the contribution of renewable energy here is very small, just 3.3%, comprised of biofuels and electric cars powered by renewables. The biggest slice of global energy demand (51%) is heating, which is covered mostly by using natural gas and heating oil. Only 10% of heating demand is supplied by renewables, with the biggest contributor being biomass. Solar thermal panels, which use energy from the sun to heat water, have existed for more than 120 years, but they only supply 1% of the world’s heating needs.

If we were to add all sectors of global energy demand together, we’d see renewables only supply around 10%. Despite a constant increase in total renewable energy generation – which grew by 21.5% between 2013 and 2018 – that increase wasn’t enough to offset the total increase in demand caused by the growing population and our increased use of energy in general.

Out of the total growth in our energy demand since 2013, renewables currently make up less than one-third. The rest is still met by older forms of energy, like fossil fuels.

Global energy trends, 2013-2018

This is known as the Jevon’s paradox. Appliances are getting more efficient at using energy, and so becoming cheaper to use. Because they are cheaper, we tend to have more of them and use them more often, leading to an overall increase in energy use.

Electric car sales are increasing worldwide – a 40% increase in 2019 compared to 2018. This inevitably will lead to a surge in electricity demand and since we want to keep electric cars green, this surge will need to be met by renewables. But in a typical city like Athens in Greece, support for electric vehicles is coupled with a commitment to generate more of the country’s electricity with lignite – a very dirty form of coal. There are plans to eventually phase out lignite in Greece, but shouldn’t that come before the call for more electric cars? After all, an electric car is only as green as the electricity that powers it.

The same goes for the biggest source of energy demand – heating. Many countries plan to switch natural gas and oil heating to electric alternatives and demand is expected to grow by 4.6% by 2025. But one might wonder, will it make a difference if our electricity isn’t that green to begin with?

Energy demand will keep increasing. We must rapidly increase how much of the energy we use is generated by renewables. One small step in that direction would be recognising that electricity is only part of the necessary transformation for a cleaner, better tomorrow.

George Loumakis, Lecturer in Energy, Glasgow Caledonian University

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

The end-Permian mass extinction is considered to be the most devastating biotic event in the history of life on Earth – it caused dramatic losses in global biodiversity, both in water and on land. About 90% of marine and 70% of terrestrial (land) species went extinct. This event may have been responsible for opening up niche spaces that ushered in the age of the dinosaurs. We know that the end-Permian in the marine realm happened about 251.9 million years ago – but the age and duration of the extinction on land, and whether it coincided with the marine extinctions, is one of the most hotly debated topics in palaeontology.

New research from South Africa’s Free State province may go some way to settling the debate. Dr Jennifer Botha, who led the research team, explained the findings to The Conversation Africa’s Natasha Joseph.

What did you find in your research?

The South African Karoo Basin preserves the most complete sequence of the end-Permian extinction on land. In our study we examined a site in the country’s Free State province to try and figure out when the end-Permian mass extinction happened. Our findings suggest the answer is a maximum of 251.7 million years ago, with an error margin of about 300 000 years either way; geologically speaking this is quite short and still falls within the 251.9 marine date. This suggests the land extinction event happened at the same time as the marine extinction event.

How did you figure this out?

The Karoo Basin, which includes about two-thirds of South Africa and parts of Lesotho, is the best region in the world for studying the end-Permian extinction on land. This is because of its rich fossil record and relatively complete sedimentological sequence.

Our research involved a comprehensive study of palaeontological, sedimentological, geochemical and detrital zircon data from the Free State site. Zircons are crystals found in volcanic ash and their radioisotopes – variants of different chemical elements – can be used to date the sediments in which they are found. Zircons from an ash bed provide the most accurate dates, but detrital zircons, which have been redeposited in the sediments, can also be used when a pristine ash bed is lacking.

We collected fossils from the site to pinpoint the palaeontologically-defined extinction. We also studied the sediments, which allowed us to see how and when the climate changed during the extinction. This also helped us to pinpoint the event.

We then collected carbonate nodules (lumps of rock containing carbonate) from paleosols at the site – these are ancient soils. Analysing the isotopes from these palaeosols showed us they were similar to palaeosols found at other terrestrial and marine sites dating back to the Permian and Triassic periods. The Triassic Period immediately followed the Permian Period.

All of our analysis suggests that there was a mass extinction event at the time of the end-Permian, on land – and more importantly that it happened at the same time as the marine end-Permian extinction.

Our findings have global ramifications. They do not support previous arguments that propose the end-Permian extinction occurred later on land compared to the sea. Instead, they suggest these events happened at the same time.

Why is this sort of dating important? What is the value in knowing how long ago something happened?

Being able to connect the land and marine extinctions to a single event shows just how catastrophic the end-Permian mass extinction was.

This type of research has applications to understanding the current mass extinction in what has been called the sixth mass extinction. That’s because any information gleaned from past mass extinctions can give us insight into how and why organisms are going extinct today. We can also, as I’ve written before, use information from the past to predict which species might survive and which may be more sensitive to extinction.

Jennifer Botha, Specialist Museum Scientist and Head of Department (National Museum, Bloemfontein) and Research Affiliate, University of the Free State

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MIT Graduate Program in Science Writing: “The Great Dying”

From climate change to omnipresent plastic waste, 2019 delivered a lot of discouraging environmental news. Several special reports this year from the Intergovernmental Panel on Climate Change documented how global warming is altering the planet’s lands, forests, oceans and frozen regions.

Another U.N. report warned that the Earth is losing species at an alarming rate, with around 1 million animal and plant species facing extinction. Key causes include changes in land use, such as clearing forests for agriculture; unsustainable fishing rates; climate change; pollution; and the spread of invasive species.

Governments may seem unable or unwilling to confront these challenges, but scholars are proposing innovative solutions. Here are three articles that we published this year that put forth responses to urgent environmental challenges.

1. Cooling the planet and saving species

Climate change and biodiversity loss are interconnected problems that together can seem overwhelming. But in a study published in April, 18 scientists proposed a “Global Deal for Nature” that can help avert both catastrophic climate change and mass extinction.

The plan identifies about a thousand “ecoregions” on land and sea that each contain unique ensembles of species and ecosystems, and also help curb climate change by storing carbon.

“Our plan would require a budget of some US$100 billion per year. This may sound like a lot, but for comparison, Silicon Valley companies earned nearly $60 billion in 2017 just from selling apps,” Arizona State University conservation scientist Greg Asner, a co-author of the report, wrote for The Conversation. “Today, however, our global society is spending less than a tenth of that amount to save Earth’s biodiversity.”

“Forests, grasslands, peatlands, mangroves and a few other types of ecosystems pull the most carbon from the air per acre of land,” Asner notes. “Protecting and expanding their range is far more scalable and far less expensive than engineering the climate to slow the pace of warming. And there is no time to lose.”

2. Stemming the tide of plastic trash

Global markets for scrap material, including recyclables, have been in turmoil since early 2018, when China – which was importing a large share of the world’s scrap – shut that window almost completely. This year other Asian countries followed suit, saying they would no longer accept materials they were ill-equipped to handle.

These shocks have left U.S. scrap dealers searching for markets. Many are sending plastics – the hardest materials to recycle – to landfills.

Alarmed by these developments and the growing scale of plastic waste, many communities and businesses are intensifying the search for new solutions.

“Recycling authorities have launched public education campaigns, and investment in recycling infrastructure is on the rise,” reports Kate O’Neill, professor of global environmental politics at the University of California, Berkeley. “There is palpable energy at trade meetings around improving options for plastics recycling. Chinese companies are investing in U.S. pulp and paper recycling plants, and may extend into plastics.”

This process won’t be quick, since it also requires action at the global level to connect national policies. And reducing production and use of plastic remains key. “But as one Asian country after another shuts the door on scrap exports, it is becoming increasingly clear that business as usual will not solve the plastic pollution challenge,” O’Neill writes.

3. A new New Deal for US farmers

Severe weather, corporate consolidation in agriculture and a trade war with China put heavy pressure on U.S. farmers in 2019. Farm bankruptcies are at historic highs, and many experts wonder where the next generation of farmers will come from.

Social scientists Maywa Montenegro of the University of California, Davis, Annie Shattuck of Indiana University and Joshua Sbicca of Colorado State University see this convergence as an economic, environmental and social crisis for farming communities. In response they propose a “just transition” to a system that cuts carbon emissions from agriculture, makes farmers less vulnerable to the effects of climate change and delivers economic justice to rural communities.

“Two elements are essential: Agriculture based in principles of ecology, and economic policies that end overproduction of cheap food and reestablish fair prices for farmers,” they assert.

To picture what such a transition would look like, they point to New Deal agriculture policies adopted in the 1930s that directed public investments to rural communities, set price floors for crops and paid farmers to adopt conservation policies. This system was largely scrapped after World War II in favor of rules that promoted large-scale commodity production and maximized output. Today, the authors argue, farmers are locked into an economic model that is “unsustainable for farmers, eaters and the planet.”

But in political and agricultural circles, new proposals are emerging for reducing corporate power in agriculture and restoring parity for farmers – payment that reflects production costs. Redirecting an industry this large is a long, slow process, but Montenegro, Shattuck and Sbicca assert that “if policymakers can envision a contemporary version of ideas in the original New Deal, a climate-friendly and socially just American agriculture is within reach.”

Editor’s note: This story is a roundup of articles from The Conversation’s archives.

Jennifer Weeks, Environment + Energy Editor, The Conversation

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