Study finds lands used for grazing can worsen or help climate change
Too much livestock on a given amount of land can lead to carbon losses, but appropriate numbers can actually help sequester the carbon.
When it comes to global climate change, livestock grazing can be either a blessing or a curse, according to a new study, which offers clues on how to tell the difference.
If managed properly, the study shows, grazing can actually increase the amount of carbon from the air that gets stored in the ground and sequestered for the long run. But if there is too much grazing, soil erosion can result, and the net effect is to cause more carbon losses, so that the land becomes a net carbon source, instead of a carbon sink. And the study found that the latter is far more common around the world today.
Long-term research highlights environmental impact of agriculture
Study carried out in ten micro-basins of the Xingu River, in Mato Grosso
How to reconcile the expansion of agricultural frontiers with the maintenance of the basin landscape and the integrity of the hydrological cycle, which are so necessary for human life? And how does all this have to do with food security? The search for these answers led researcher Márcia Macedo to develop, together with other researchers, a long-term study in ten micro-basins of the Xingu River, in Mato Grosso.
It was through the Tanguro Project, an initiative of the Amazon Environmental Research Institute (Ipam) in the city of Querência, that the researcher found the perfect environment to develop her first experiment in search of these answers. In an open-air laboratory, which brings together researchers from several countries, Márcia also had access to watercourses located on land with different uses. “It’s a place where we can compare forested basins, that is, integral ones, and basins with intensive agriculture. So we researched four basins for forestry and six basins for agriculture,” she explains.
Scientists from Woodwell Climate Research Center are among the 195 leading experts in forest ecosystems, climate change, and the carbon cycle who have come together to urge the Biden Administration to immediately declare a moratorium on all logging in mature and old-growth forests on federal lands. The signers include seven members of the National Academies of Sciences and some of the most notable names in climate science.
The letter comes amid growing concerns within the scientific community around the U.S. Forest Service and Bureau of Land Management’s response to an executive order, issued by the Biden Administration on Earth Day 2022, to establish guidelines and best practices to safeguard mature and old-growth forests on federal lands. The letter was initiated by Dr. Beverly Law, Professor Emeritus at Oregon State University, and Dr. Bill Moomaw, Professor Emeritus at Tufts University and Distinguished Visiting Scientist at Woodwell Climate. Last week, Woodwell Climate Senior Scientist and signatory Dr. Rich Birdsey delivered the letter’s message to the Mature and Old Growth Science Summit, hosted by the Forest Stewards Guild, the U.S. Forest Service, and the Society of American Foresters.
“Old-growth forests are made up of our oldest, and typically largest, trees that store massive amounts of carbon,” said Dr. Rich Birdsey. “We need to protect old growth, as well as younger mature forests that can attain old-growth characteristics with time.”
“The carbon storage function these forests play is essential to our efforts to reduce carbon emissions and mitigate the impacts of the rapidly changing climate, yet millions of acres of mature and old-growth forests stand on federal lands that are vulnerable to logging,” said Dr. Beverly Law. “To align with the United States’s commitments to ending global forest deforestation and degradation, we must urgently halt any additional logging of these critical natural resources.”
The scientists point to recent efforts by the agencies to increase timber sales and logging of these forests rather than increasing their protection as directly contrary to these objectives, and call on President Biden to issue a new executive order prohibiting activities that further forest degradation in the short-term, while the Administration works, in partnership with policy and climate leaders, to develop and implement effective, long-term management policies. Reducing timber harvesting of carbon-dense forests can have an immediate effect of lowering emissions and is the most significant action that the U.S. can take to immediately limit greenhouse gasses.
“With their 2022 executive order to protect mature and old-growth forests, the Biden Administration laid the groundwork for the U.S. to emerge as a global leader in conserving these forests and making good on international climate commitments,” said Dr. William Moomaw. “Halting logging in the interim is necessary to protect these resources now, while also working with the agencies to develop strong, long-term policies consistent with the Administration’s commitments to addressing climate change and safeguarding forests as a natural climate solution.”
The full letter can be found here.
Last month was hottest February ever recorded. It’s the ninth-straight broken record
For the ninth straight month, Earth has obliterated global heat records — with February, the winter as a whole and the world’s oceans setting new high-temperature marks, according to the European Union climate agency Copernicus.
The latest record-breaking in this climate change-fueled global hot streak includes sea surface temperatures that weren’t just the hottest for February, but eclipsed any month on record, soaring past August 2023’s mark and still rising at the end of the month. And February, as well the previous two winter months, soared well past the internationally set threshold for long-term warming, Copernicus reported Wednesday.
Continue reading on Associated Press News.
Study pinpoints links between melting Arctic ice and summertime extreme weather in Europe
New research shows how last year’s warming melted ice in Greenland that increased flows of fresh, cold water into the North Atlantic, upsetting ocean currents in ways that lead to atmospheric changes.
The Arctic Ocean is mostly enclosed by the coldest parts of the Northern Hemisphere’s continents, ringed in by Siberia, Alaska and the Canadian Arctic, with only a small opening to the Pacific through the Bering Strait, and some narrow channels through the labyrinth of Canada’s Arctic archipelago.
But east of Greenland, there’s a stretch of open water about 1,300 miles across where the Arctic can pour its icy heart out to the North Atlantic. Those flows include increasing surges of cold and fresh water from melted ice, and a new study in the journal Weather and Climate Dynamics shows how those pulses can set off a chain reaction from the ocean to the atmosphere that ends up causing summer heatwaves and droughts in Europe.
Read more on Inside Climate News.
How poop turns into forests
Did you know the world’s largest tropical forest is partly formed by seeds emerging from poop? Ecologist Ludmila Rattis reveals the surprisingly fruitful benefits of letting nature take care of its own business, sharing how the digestive habits of tapirs — pig-like creatures that roam Amazonia — spread seeds that help regenerate the forest and promote climate resilience worldwide. (Even nature’s waste is put to good use!)
Freeze on Russian collaboration disrupts urgently needed permafrost data flow
Warming temperatures in the Arctic are accelerating the thaw of carbon-rich permafrost and threatening to add massive amounts of carbon dioxide and methane to an atmosphere already overheating from the buildup of anthropogenic greenhouse gas emissions.
More than half that permafrost lies beneath remote Russian soil, where scientists have long worked in an international research community that freely shared its field stations, climate sensors and data sets to better understand the rapidly changing polar region’s planetary impacts.
Researchers are especially eager to know when a dangerous tipping point may be reached that would trigger the release of vast amounts of greenhouse gases stored in frozen soils.
But then came the Russian invasion of Ukraine on Feb. 24, 2022, and all that cooperation came to a halt, part of the fallout of Western sanctions on Russia. Since then, international researchers outside Russia have applied creative workarounds in order to continue their research, but problems remain.
Drought, driven by a combination of El Niño and climate change, has disrupted shipping through the Panama Canal in recent months. Dropping water levels in Lake Gatun forced Panama Canal authorities to pose restrictions on the number of ships that can pass the canal, dropping from the normal 38 down to 24 transits a day by November 2023, causing long queues at nearby ports as ships wait their turn to pass. If the restrictions remain in place through 2024, there could be up to 4,000 fewer ships—with cargo ranging from children’s toys, to solar panel components, to life-saving insulin—passing the canal in 2024. Delay and disruption along shipping routes will only become a more common occurrence in a warmer world. These 7 graphics show how drought threatens serious disruptions to the global supply chain.
1. Panama in Drought
Panama is currently suffering a prolonged drought that began in early 2023 and has not let up. In October, rainfall was 43% lower than average levels, making it the driest October since the 1950s. For the area around the canal, 2023 was one of the driest two years since record keeping began in the country.
2. El Niño-driven dryness exacerbated by climate
Panama’s severe drought is being exacerbated by the double-whammy of a strong El Niño and record-breaking global warming— exceeding the pre-industrial temperature average by 1.35 C. El Niño is a natural climate fluctuation that brings warmer-than-average air and ocean waters to the West coast of the Americas. That influx of warmth can vary in strength and last between nine and twelve months, and the National Oceanic and Atmospheric Administration (NOAA) predicts it will continue into at least April of 2024.
The severity of El Niño fluctuations is linked to climate change. Climate modeling shows swings between El niño and its counterpart La niña have been growing more extreme, resulting in the more frequent and intense events seen in the past few decades Under high emission scenarios, in which we don’t get warming in check, El Niño events could become 15-20% stronger.
3. Gatún Lake levels continue to drop
The drought has had a particularly profound effect on the man-made Gatún Lake, which holds the water supply that operates the Panama Canal. On January 1, 2024 water levels in Gatún Lake were lower than in any other January on record, almost 6 ft lower than January 1, 2023. Millions of gallons of water from Gatún, along with other regional lakes, are used to fill the locks that raise ships above sea level for the passage over Panama’s terrain. Insufficient water supply jeopardizes ship passage
Not only does Gatún Lake feed the locks that power the Canal, it also supplies drinking water to millions of residents in the central region of the country, including two major cities: Panama City and Colón. As both Panama’s population and the scale of global shipping has grown, there has been greater demand on the lake for freshwater.
4. Less water means fewer, smaller ships
In response to dropping water levels, Panama Canal Authorities have been forced to institute restrictions on ship passages. Ship transits are currently limited to 24 per day until April of 2024, when the authorities will re-evaluate at the start of the rainy season. The number of ship passages was 30% lower than usual by the end of 2023. The unreliability of transit through Panama has already prompted some ships to re-route.
Lower water levels also restrict the size of ships that can pass through the canal, as larger, heavier vessels sit lower in the water, putting them at higher risk of running aground in shallower waters. Large ships also require more lake water to lift them in the locks. As global shipping volume has grown, many shipping fleets have, too— relying on massive vessels that can carry more goods, but are harder to navigate through shallow waterways like the Panama Canal.
5. Disruptions in Panama affect global trade
The Panama Canal accounts for 5% of global shipping, so disruptions here affect the worldwide supply chain, resulting in delayed shipments, more fuel usage, and GDP losses.
The impacts of shipping disruptions in the Panama Canal are also being compounded by political events in the Red Sea. The Suez Canal, an alternative route for ships bound between Europe and Asia, has also had shipping disrupted by attacks from the Houthis, a Yemeni military group targeting Israel-bound ships. With both the Panama and Suez Canals becoming less reliable routes, more ships will be forced to take the long way around— traveling down to the southern points of Africa and South America.
6. Arctic ship travel does not offer an alternative route
Far to the north, another waterway is being rapidly altered by climate change. As the Arctic warms faster than any other place on the planet, summer sea ice has been disappearing at a rate of almost 13% per decade. This has opened up new lanes of ice-free water that some countries are eying as potential new routes. But navigating through a melting Arctic is still dangerous, and the majority of new ship traffic in the Arctic is comprised of smaller military or fishing boats, rather than the large shipping vessels used to carry commercial cargo.
Furthermore, increased ship traffic in the Arctic has the potential to further emissions, as melting ice could open up access to new sources of oil and natural gas— perpetuating climate warming.
7. Temperatures are still rising
Though December rains saved Panama Canal officials from instituting further restrictions on ship passage, the region is still experiencing El Niño, and sea surface temperatures in early 2024 have continued to climb higher than 2023. Each day in 2024 has recorded the highest temperatures on record for that calendar date. The only path to stabilizing global shipping lies in stabilizing the global climate.