Category Archives: Carbon, Climate & Bioenergy

For the last century, rising levels of carbon dioxide helped plants grow faster, a rare silver lining in human-caused climate change. But now, as drier conditions set in across much of the globe, plant growth may be failing to keep up with emissions, a new study suggests. Through photosynthesis, plants convert water and carbon dioxide into storable energy. By burning fossil fuels, humans have driven up carbon dioxide levels, from around 280 parts per million before the Industrial Revolution to 417 parts per million last year. That extra carbon dioxide has sped up photosynthesis, spurring plants to soak up more of our emissions and grow faster. Since 1982, plants globally have added enough leaf cover to span an area roughly twice the size of the continental U.S. But the effect appears to be wearing off. While carbon dioxide levels continue to climb, more than a century of warming has also made the climate more hostile to plants.

Much of America is baking under record heat or seeing sunlight filtered through the haze of wildfires thousands of miles away. We need to reduce greenhouse gases to slow the effects of global warming. One tool that has not yet been used to its fullest extent is trading carbon offset credits. …To achieve this, companies purchase carbon credits issued by projects that aim to reduce or eliminate emissions. Some examples include renewable energy initiatives such as wind farms, forest conservation and afforestation, and carbon capture projects. By doing so, they create a market-driven approach to mitigating the growth in greenhouse gas emissions…But for offset trading to work, the market needs to be much broader. Climate change is a global crisis, after all, so we need a solution that’s global, too. …Along with this market would come a global set of standards and regulation for verification so everyone is operating on the same page. 

Activists are condemning a recent Forest Service report to Congress, saying one of its conclusions supports a policy that would worsen climate change by allowing the removal of old trees that absorb large amounts of carbon. Some scientists and environmental groups say the report inaccurately states that older trees remove less carbon than younger trees — a conclusion they fear will encourage a policy of logging older forests. The report …could lead to more logging, said Norman Christensen, a professor at Duke University’s Nicholas School of the Environment. The Forest Service said that U.S. forests will rapidly lose their ability to soak up carbon and could become net carbon emitters by 2070 instead of carbon sinks. The report says development along with worsening wildfires and tornadoes will destroy large chunks of U.S. forests and disrupt their carbon absorption. The report also says aging forests absorb less carbon than younger forests as tree growth slows.

A landmark ruling found the state of Montana violated young people’s constitutional rights to a “clean and healthful environment,” marking the first time a U.S. court has connected the government’s fossil fuel promotion with harm to youth from climate change neglect. The case, Held vs. State of Montana, involved 16 Montana youths who aimed to protect their rights to a healthy environment, dignity and freedom. Youth plaintiffs and expert witnesses argued that the state violated their constitutional right to a clean environment, including safeguarding air, water, wildlife and public lands from climate-related threats like droughts, wildfires and floods. Montana Judge Kathy Seeley ruled in favor of the young plaintiffs, stating that laws prohibiting climate change consideration in fossil fuel activities were unconstitutional; the decision highlighted climate impacts, irreversible injuries from greenhouse gas emissions, and the need for science-based climate measures. The plaintiffs did not seek money in their lawsuit.

Reaching “net zero” will require capturing large amounts of emissions from activities that are hard to decarbonize, like making cement:

• How much more carbon capture is needed? Twice as much carbon would need to be removed by that year on an annual basis using trees and soils and roughly 1,300 times as much would have to be sucked up using new technologies.
• Why wouldn’t planting a gazillion more trees get us further? Researchers in 2017 estimated that reforestation and other such “natural climate solutions” could produce 37% of the cuts needed by 2030… But that much tree-planting would likely require land three times the size of India. 
• What are the other main options? There are two main methods, known as carbon capture and storage (CCS), and direct air capture (DAC).
• Are there other methods of carbon capture? Bioenergy with carbon capture and storage (BECCS). …Soil carbon sequestration.

An alarming report from the US Department of Agriculture predicts that by 2070, the nation’s forests will release substantially more carbon than they store. Forests in the US – bar those in Alaska – will no longer absorb 150 million metric tons of carbon a year within five decades, experts say. To understand how a carbon sink can become a carbon tap, we have to consider the lifecycle of a healthy forest, where new growth matures into old growth and old growth dies and makes room for new growth. But today, in North America, not enough young trees are being planted and allowed to grow up. This means that mature forests are outpacing young forests, which are also more likely to be harvested or killed due to climate effects like wildfires, drought, or storms. The overall shift to an older age cohort of trees means that in the future, forests in the US could be dying more than they are growing.

Ocean carbon removal startup Running Tide has delivered its first-ever carbon removal credits to inaugural buyer Shopify Inc. Running Tide sank more than 1,000 tons of limestone-coated wood waste to the ocean floor roughly 100 miles south of Iceland. That wood would have otherwise been burned, releasing carbon dioxide into the atmosphere. Instead, the startup says the CO2 contained in this material will be safely stored on the ocean floor for 800 to 10,000 years, depending on a variety of factors. The process removed 275 net tons of carbon dioxide equivalent after accounting for project-related emissions, with 100 tons going to Shopify. …Running Tide has faced controversy in recent years, most notably after MIT Technology Review raised concerns around the company’s practices having potentially negative ecological impacts. …Running Tide is also exploring carbon removal methods that include increasing the ocean’s alkalinity, which could up its capacity to absorb CO2. 

Three letters to the editor re: The Aug. 3 news article “Planting a trillion trees would do little to curb global warming”

• Brian Kittler, Cornelius, Ore., forest restoration lead with American Forests. ...Conserving forests is just as important as adding new ones. That’s why my organization and others work to protect existing forests, manage forestlands for climate resilience and long-term health, and restore burned and damaged forests. …We cannot win on climate with forests alone, but we cannot win without them.
• Rita Hite, Washington, president and chief executive of the American Forest Foundation. Science shows that reforestation is the single largest potential source of natural climate mitigation. …The most immediate path to those solutions is through comprehensive policy such as the Inflation Reduction Act.
• Dan Weiss, Washington. In light of his pro-logging record, Mr. McCarthy’s tree proposal is redwood-size chutzpah. …Mr. McCarthy’s hypocritical actions would increase, not reduce, the existential threat posed by climate change.

More than once this summer, U.S. cities have been hazed by smoke from wildfires. With orange sunsets and grey, hazy days, the smoke makes climate change visible in the sky. Publishers and nongovernmental organizations seem already to have noticed the uptick in the number, intensity, and duration of wildfires in the past several years. And so in time for this summer’s burn, they have released several new books and reports, five just since the start of the new year. As a counterpoint to the joyous “grove of tree books” Yale Climate Connections put together for Arbor Day, this month’s bookshelf presents 12 titles on the climate-charged threat to their — and our — future: wildfires.

James Hansen in 1988

The world is shifting towards a superheated climate not seen in the past 1m years, prior to human existence, because “we are damned fools” for not acting upon warnings over the climate crisis, according to James Hansen, the US scientist who alerted the world to the greenhouse effect in the 1980s. Hansen, whose testimony to the US Senate in 1988 is cited as the first high-profile revelation of global heating, warned in a statement with two other scientists that the world was moving towards a “new climate frontier” with temperatures higher than at any point over the past million years, bringing impacts such as stronger storms, heatwaves and droughts. The world has already warmed by about 1.2C since mass industrialization, causing a 20% chance of having the sort of extreme summer temperatures currently seen in many parts of the northern hemisphere, up from a 1% chance 50 years ago, Hansen said.

A common response to biomass is: how can burning biological matter be sustainable or carbon neutral? But biomass, in terms of its carbon emissions, is conceptually circular. The tree used to produce the biomass has absorbed all the carbon that is released on burning, so over a typical cycle of 30 years, there is no net addition to carbon in the atmosphere, unlike burning fossil fuels. …While there is still a carbon cost of making and transporting pellets, this is a fraction of the carbon released by burning coal or gas. …Although using forestry waste may be dismissed by some as simply burning trees, investors should bear in mind that forest coverage in the US and Canada is stable, and new trees are planted to replace those felled, making this a sustainable resource. North American forestry is a heavily regulated industry with strict environmental standards.

…Over the past two years, several big insurers, including Allstate and State Farm, have scaled back their home insurance businesses in California to avoid paying billions for wildfire damage, or have halted sales of new policies altogether. …Insurance companies in states like Colorado, Louisiana and Florida are paring down business to shield themselves from ballooning losses as climate change fuels more-intense disasters. …insurers say they can’t increase rates enough to cover the damage occurring in the riskiest places. Meanwhile, the cost of disasters keeps going up. People continue moving to regions vulnerable to hurricanes or prone to wildfires. …Given the near-certainty that the impacts of climate change will get worse, experts say it is critical to build homes that are more resilient. …In the future, slowing down or even stopping development in the riskiest areas is ultimately part of the solution to rising insurance losses, experts say.