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    Cyclones in the Arctic are becoming more intense and frequent

    CHICAGO – In January 2022, a cyclone blitzed a large expanse of ice-covered ocean between Greenland and Russia. Frenzied gusts galvanized 8-meter-tall waves that pounded the region’s hapless flotillas of sea ice, while a bombardment of warm rain and a surge of southerly heat laid siege from the air.

    Six days after the assault began, about a quarter, or roughly 400,000 square kilometers, of the vast area’s sea ice had disappeared, leading to a record weekly loss for the region.

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    The storm is the strongest Arctic cyclone ever documented. But it may not hold that title for long. Cyclones in the Arctic have become more frequent and intense in recent decades, posing risks to both sea ice and people, researchers reported December 13 at the American Geophysical Union’s fall meeting. “This trend is expected to persist as the region continues to warm rapidly in the future,” says climate scientist Stephen Vavrus of the University of Wisconsin–Madison.

    Rapid Arctic warming and more destructive storms

    The Arctic Circle is warming about four times as fast as the rest of Earth (SN: 8/11/22). A major driver is the loss of sea ice due to human-caused climate change. The floating ice reflects far more solar radiation back into space than naked seas do, influencing the global climate (SN: 10/14/21). During August, the heart of the sea ice melting season, cyclones have been observed to amplify sea ice losses on average, exacerbating warming.

    There’s more: Like hurricanes can ravage regions farther south, boreal vortices can threaten people living and traveling in the Arctic (SN: 12/11/19). As the storms intensify, “stronger winds pose a risk for marine navigation by generating higher waves,” Vavrus says, “and for coastal erosion, which has already become a serious problem throughout much of the Arctic and forced some communities to consider relocating inland.”

    Climate change is intensifying storms farther south (SN: 11/11/20). But it’s unclear how Arctic cyclones might be changing as the world warms. Some previous research suggested that pressures, on average, in Arctic cyclones’ cores have dropped in recent decades. That would be problematic, as lower pressures generally mean more intense storms, with “stronger winds, larger temperature variations and heavier rainfall [and] snowfall,” says atmospheric scientist Xiangdong Zhang of the University of Alaska Fairbanks.

    But inconsistencies between analyses had prevented a clear trend from emerging, Zhang said at the meeting. So he and his colleagues aggregated a comprehensive record, spanning 1950 to 2021, of Arctic cyclone timing, intensity and duration.

    Arctic cyclone activity has intensified in strength and frequency over recent decades, Zhang reported. Pressures in the hearts of today’s boreal vortices are on average about 9 millibars lower than in the 1950s. For context, such a pressure shift would be roughly equivalent to bumping a strong category 1 hurricane well into category 2 territory. And vortices became more frequent during winters in the North Atlantic Arctic and during summers in the Arctic north of Eurasia.

    What’s more, August cyclones appear to be damaging sea ice more than in the past, said meteorologist Peter Finocchio of the U.S. Naval Research Laboratory in Monterey, Calif. He and his colleagues compared the response of northern sea ice to summer cyclones during the 1990s and the 2010s.

    August vortices in the latter decade were followed by a 10 percent loss of sea ice area on average, up from the earlier decade’s 3 percent loss on average. This may be due, in part, to warmer water upwelling from below, which can melt the ice pack’s underbelly, and from winds pushing the thinner, easier-to-move ice around, Finocchio said.

    Stronger spring storms spell trouble too

    With climate change, cyclones may continue intensifying in the spring too, climate scientist Chelsea Parker said at the meeting. That’s a problem because spring vortices can prime sea ice for later summer melting.

    Parker, of NASA’s Goddard Space Flight Center in Greenbelt, Md., and her colleagues ran computer simulations of spring cyclone behavior in the Arctic under past, present and projected climate conditions. By the end of the century, the maximum near-surface wind speeds of spring cyclones — around 11 kilometers per hour today — could reach 60 km/h, the researchers found. And future spring cyclones may keep swirling at peak intensity for up to a quarter of their life spans, up from around 1 percent today. The storms will probably travel farther too, the team says.

    “The diminishing sea ice cover will enable the warmer Arctic seas to fuel these storms and probably allow them to penetrate farther into the Arctic,” says Vavrus, who was not involved in the research.

    Parker and her team plan to investigate the future evolution of Arctic cyclones in other seasons, to capture a broader picture of how climate change is affecting the storms.

    For now, it seems certain that Arctic cyclones aren’t going anywhere. What’s less clear is how humankind will contend with the storms’ growing fury. More

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    Extreme weather in 2022 showed the global impact of climate change

    It was another shattering year.

    Climate change amped up weather extremes around the globe, smashing temperature records, sinking river levels to historic lows and raising rainfall to devastating highs. Droughts set the stage for wildfires and worsened food insecurity. Researchers found themselves pondering the limits of humans’ ability to tolerate extreme heat (SN: 7/27/22).

    The extreme events from 2022 pinpointed on the map below are just a sample of this year’s climate disasters. Each was exacerbated by human-caused climate change or is in line with projections of regional impacts.

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    In its Sixth Assessment Report, released in 2021 and 2022, the United Nations’ Intergovernmental Panel on Climate Change, or IPCC, warned that humans are dramatically overhauling Earth’s climate (SN: 8/9/21). Earth’s average surface temperature has already risen by at least 1.1 degree Celsius since preindustrial times, thanks to human inputs of heat-trapping gases to the atmosphere, particularly carbon dioxide and methane (SN: 3/10/22). That warming has shifted the flow of energy around the planet, altering weather patterns, raising sea levels and turning past extremes into new normals (SN: 2/1/22).

    And the world will have to weather more such climate extremes as carbon keeps accumulating in the atmosphere and global temperatures continue to rise. But IPCC scientists and others hope that, by highlighting the regional and local effects of climate change, the world will ramp up its efforts to reduce climate-warming emissions — averting a more disastrous future. More

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    2022’s biggest climate change bill pushes clean energy

    The world needed bold climate action this year, and we got it.

    California and other states announced plans to phase out gas-powered cars after 2035. The United States ratified an international treaty to slash production of the climate-warming hydrofluorocarbons used in cooling and refrigeration. The European Union is finalizing its plan to cut greenhouse gas emissions by 55 percent relative to 1990s levels by 2030. The list of legislative victories goes on.

    But the biggest win came August 16, when President Joe Biden signed into law the Inflation Reduction Act.

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    The historic legislation marks the first major move by the United States, which has emitted more carbon dioxide than any other country, toward neutralizing greenhouse gas emissions. It gets the ball rolling by investing $369 billion into accelerating the adoption of wind, solar and other renewable energy sources and decarbonizing the economy. By the end of the decade, the act will help cut U.S. greenhouse gas emissions by around 40 percent of the levels in 2005, when U.S. emissions nearly peaked, scientists project, bringing the nation within reach of fulfilling its pledge to halve emissions by 2030.

    The legislation is no panacea for the climate emergency, but researchers and activists are optimistic that it will be the helping hand that clean energy needs to flourish. “There would be no way to really mitigate the climate crisis without the investments in this bill,” says Raul Garcia, a legislative director at Earthjustice, a nonprofit environmental law organization.

    Here’s a look at some of the law’s major provisions and a few of its limitations.

    Cheaper clean energy

    The law aims to ease and incentivize the transition away from fossil fuels by creating tax credits that reduce the cost for companies to adopt clean energy. For instance, small businesses can qualify for credits that support up to 30 percent of the cost of transitioning to solar power.

    The act also aims to help consumers, with $9 billion for rebates that help people ditch gas and buy appliances powered by electricity, such as electric induction cooktops and heat pump water heaters. Households can also get up to $7,500 in tax credits for electric vehicle purchases.

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    “It’s huge,” Denise Mauzerall, an atmospheric scientist at Princeton University, says of the law’s potential to advance clean energy. But if the United States is to take full advantage of the increased clean energy capacity, it will be crucial to also construct sufficient infrastructure to deliver that energy, she notes. The bill offers only some support to build overhead power lines and other ways to transmit energy. “Without transmission,” she says, “we will really slow ourselves down.”

    Clean energy jobs and goods

    A major goal is to build up a clean energy economy by promoting high-quality jobs in industries such as solar and wind. To maximize tax credits, companies must pay workers a “prevailing wage” and employ apprentices to work a minimum number of hours on clean energy projects.

    The legislation also invests in the domestic manufacturing of clean energy goods. Tax credits of up to 30 percent are available to companies that build or recycle wind turbine blades, solar panels, energy storage equipment and other clean energy products, and funds grants to retool factories to make electric vehicles.

    Through tax credits, the Inflation Reduction Act promotes high-quality jobs in the wind and energy industries, like workers at solar power stations.Sinology/Moment/Getty Images

    Reducing pollution

    Methane — a greenhouse gas that can trap more than 25 times as much heat as CO2 — is another target. The legislation devotes $850 million to the monitoring and mitigation of methane emissions from fossil fuel operations. It also establishes a fine for operations that annually release amounts of methane that exceed 25,000 metric tons of CO2 equivalent.

    And CO2 is legally defined as an “air pollutant,” cementing the Environmental Protection Agency’s authority to regulate its production under the Clean Air Act.

    But there’s more to the climate problem than decarbonizing today’s pollutive energy industry, Mauzerall says. “Going forward, we need to pay more attention to reducing emissions from the agricultural sector,” she says. About 11 percent of U.S. greenhouse gas emissions and about a third of global emissions come from agriculture (SN: 5/7/22 & 5/21/22, p. 22).

    Climate justice

    Billions of dollars are slated to go toward climate justice, a movement that confronts the disproportionate impacts of climate change on marginalized communities. Funding includes $2.8 billion in grants for community-based projects, such as those that increase energy efficiency in affordable housing developments or monitor air quality in marginalized communities.

    “But there are some troubling provisions,” Garcia says. The law authorizes new offshore oil and gas leases and provides fossil fuel companies with carbon capture and sequestration tax credits. These could prolong the life of pollutive oil and gas operations, which are often located near marginalized communities.

    It will be crucial to follow these investments with laws that enforce both climate justice and the clean energy transition, Garcia says. “We need rules and regulations that hold industries’ feet to the fire, to make sure that those investments are going where they need to.” More

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    Greenland’s frozen hinterlands are bleeding worse than we thought

    Sea level rise may proceed faster than expected in the coming decades, as a gargantuan flow of ice slithering out of Greenland’s remote interior both picks up speed and shrinks.

    By the end of the century, the ice stream’s deterioration could contribute to nearly 16 millimeters of global sea level rise — more than six times the amount scientists had previously estimated, researchers report November 9 in Nature.

    The finding suggests that inland portions of large ice flows elsewhere could also be withering and accelerating due to human-caused climate change, and that past research has probably underestimated the rates at which the ice will contribute to sea level rise (SN: 3/10/22).

    “It’s not something that we expected,” says Shfaqat Abbas Khan, a glaciologist at the Technical University of Denmark in Kongens Lyngby. “Greenland and Antarctica’s contributions to sea level rise in the next 80 years will be significantly larger than we have predicted until now.”

    In the new study, Khan and colleagues focused on the Northeast Greenland Ice Stream, a titanic conveyor belt of solid ice that crawls about 600 kilometers out of the landmass’s hinterland and into the sea. It drains about 12 percent of the country’s entire ice sheet and contains enough water to raise global sea level more than a meter. Near the coast, the ice stream splits into two glaciers, Nioghalvfjerdsfjord and Zachariae Isstrøm.

    While frozen, these glaciers keep the ice behind them from rushing into the sea, much like dams hold back water in a river (SN: 6/17/21). When the ice shelf of Zachariae Isstrøm collapsed about a decade ago, scientists found that the flow of ice behind the glacier started accelerating. But whether those changes penetrated deep into Greenland’s interior remained largely unresolved.

    “We’ve mostly concerned ourselves with the margins,” says atmosphere-cryosphere scientist Jenny Turton of the nonprofit Arctic Frontiers in Tromsø, Norway, who was not involved in the new study. That’s where the most dramatic changes with the greatest impacts on sea level rise have been observed, she says (SN: 4/30/22, SN: 5/16/13).

    Keen to measure small rates of movement in the ice stream far inland, Khan and his colleagues used GPS, which in the past has exposed the tortuous creeping of tectonic plates (SN: 1/13/21). The team analyzed GPS data from three stations along the ice stream’s main trunk, all located between 90 and 190 kilometers inland.

    The data showed that the ice stream had accelerated at all three points from 2016 to 2019. In that time frame, the ice speed at the station farthest inland increased from about 344 meters per year to surpassing 351 meters per year.

    The researchers then compared the GPS measurements with data collected by polar-orbiting satellites and aircraft surveys. The aerial data agreed with the GPS analysis, revealing that the ice stream was accelerating as far as 200 kilometers upstream. What’s more, shrinking — or thinning — of the ice stream that started in 2011 at Zachariae Isstrøm had propagated more than 250 kilometers upstream by 2021. 

    “This is showing that glaciers are responding along their length faster than we had thought previously,” says Leigh Stearns, a glaciologist from the University of Kansas in Lawrence, who was not involved in the study.

    Khan and his colleagues then used the data to tune computer simulations that forecast the ice stream’s impact on sea level rise. The researchers predict that by 2100, the ice stream will have singlehandedly contributed between about 14 to 16 millimeters of global sea level rise — as much as Greenland’s entire ice sheet has in the last 50 years.

    The findings suggest that past research has probably underestimated rates of sea level rise due to the ice stream, Stearns and Turton say. Similarly, upstream thinning and acceleration in other large ice flows, such as those associated with Antarctica’s shrinking Pine Island and Thwaites glaciers, might also cause sea levels to rise faster than expected, Turton says (SN: 6/9/22, SN: 12/13/21).

    Khan and his colleagues plan to investigate inland sections of other large ice flows in Greenland and Antarctica, with the hopes of improving forecasts of sea level rise (SN: 1/7/20).

    Such forecasts are crucial for adapting to climate change, Stearns says. “They’re helping us better understand the processes so that we can inform the people who need to know that information.” More

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    Wind turbines could help capture carbon dioxide while providing power

    Wind turbines could offer a double whammy in the fight against climate change.

    Besides harnessing wind to generate clean energy, turbines may help to funnel carbon dioxide to systems that pull the greenhouse gas out of the air (SN: 8/10/21). Researchers say their simulations show that wind turbines can drag dirty air from above a city or a smokestack into the turbines’ wakes. That boosts the amount of CO2 that makes it to machines that can remove it from the atmosphere. The researchers plan to describe their simulations and a wind tunnel test of a scaled-down system at a meeting of the American Physical Society’s Division of Fluid Dynamics in Indianapolis on November 21.

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    Addressing climate change will require dramatic reductions in the amount of carbon dioxide that humans put into the air — but that alone won’t be enough (SN: 3/10/22). One part of the solution could be direct air capture systems that remove some CO2 from the atmosphere (SN: 9/9/22).

    But the large amounts of CO2 produced by factories, power plants and cities are often concentrated at heights that put it out of reach of machinery on the ground that can remove it. “We’re looking into the fluid dynamics benefits of utilizing the wake of the wind turbine to redirect higher concentrations” down to carbon capture systems, says mechanical engineer Clarice Nelson of Purdue University in West Lafayette, Ind.

    As large, power-generating wind turbines rotate, they cause turbulence that pulls air down into the wakes behind them, says mechanical engineer Luciano Castillo, also of Purdue. It’s an effect that can concentrate carbon dioxide enough to make capture feasible, particularly near large cities like Chicago.

    “The beauty is that [around Chicago], you have one of the best wind resources in the region, so you can use the wind turbine to take some of the dirty air in the city and capture it,” Castillo says. Wind turbines don’t require the cooling that nuclear and fossil fuel plants need. “So not only are you producing clean energy,” he says, “you are not using water.”

    Running the capture systems from energy produced by the wind turbines can also address the financial burden that often goes along with removing CO2 from the air. “Even with tax credits and potentially selling the CO2, there’s a huge gap between the value that you can get from capturing it and the actual cost” that comes with powering capture with energy that comes from other sources, Nelson says. “Our method would be a no-cost added benefit” to wind turbine farms.

    There are probably lots of factors that will impact CO2 transport by real-world turbines, including the interactions the turbine wakes have with water, plants and the ground, says Nicholas Hamilton, a mechanical engineer at the National Renewable Energy Laboratory in Golden, Colo., who was not involved with the new studies. “I’m interested to see how this group scaled their experiment for wind tunnel investigation.” More

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    Climate change could turn some blue lakes to green or brown

    Some picturesque blue lakes may not be so blue in the future, thanks to climate change.

    In the first global tally of lake color, researchers estimate that roughly one-third of Earth’s lakes are blue. But, should average summer air temperatures rise by a few degrees, some of those crystal waters could turn a murky green or brown, the team reports in the Sept. 28 Geophysical Research Letters.

    The changing hues could alter how people use those waters and offer clues about the stability of lake ecosystems. Lake color depends in part on what’s in the water, but factors such as water depth and surrounding land use also matter. Compared with blue lakes, green or brown lakes have more algae, sediment and organic matter, says Xiao Yang, a hydrologist at Southern Methodist University in Dallas.

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    Yang and colleagues used satellite photos from 2013 to 2020 to analyze the color of more than 85,000 lakes around the world. Because storms and seasons can temporarily affect a lake’s color, the researchers focused on the most frequent color observed for each lake over the seven-year period. The researchers also created an interactive online map that can be used to explore the colors of these lakes.

    The approach is “super cool,” says Dina Leech, an aquatic ecologist at Longwood University in Farmville, Va., who was not involved with the study. These satellite data are “just so powerful.”

    The scientists then looked at local climates during that time to see how they may be linked to lake color around the world. For many small or remote water bodies, records of temperature and precipitation don’t exist. Instead, the researchers also relied on climate “hindcasts” calculated for every spot on the globe, which are pieced together from relatively sparse records. 

    Lakes in places with average summer air temperatures that were below 19° Celsius were more likely to be blue than lakes with warmer summers, the researchers found. But up to 14 percent of the blue lakes they studied are near that threshold. If average summer temperatures increase another 3 degrees Celsius — an amount that scientists think is plausible by the end of the century — those 3,800 lakes could turn green or brown (SN: 8/9/21). That’s because warmer water helps algae bloom more, which changes the properties of the water, giving it a green-brown tint, Yang says.

    Extrapolating beyond this sample of lakes is a bit tricky. “We don’t even know how many lakes there are in the world,” says study coauthor Catherine O’Reilly, an aquatic ecologist at Illinois State University in Normal. Many lakes are too small to reliably detect via satellite, but by some estimates, tens of thousands of larger lakes could lose their blue hue.

    If some lakes do become less blue, people will probably lose some of the resources they have come to value, O’Reilly says. Lakes are often used for drinking water, food or recreation. If the water is more clogged with algae, it could be unappealing for play or more costly to clean for drinking.

    But the color changes wouldn’t necessarily mean that the lakes are any less healthy. “[Humans] don’t value lots of algae in a lake, but if you’re a certain type of fish species, you might be like ‘this is great,’” O’Reilly says.

    Lake color can hint at the stability of a lake’s ecosystem, with shifting shades indicating changing conditions for the critters living in the water. One benefit of the new study is that it gives scientists a baseline for assessing how climate change is affecting Earth’s freshwater resources. Continued monitoring of lakes could help scientists detect future changes.

    “[The study] sets a marker that we can compare future results to,” says Mike Pace, an aquatic ecologist at the University of Virginia in Charlottesville, who was not involved with the study. “That’s, to me, the great power of this study.” More

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    Gas flares are leaking five times as much methane than previously thought

    In many oil and gas producing regions, flames light the sky. The flares burn off 98 percent of the escaping natural gas, oil and gas companies claim. But observations of three U.S. oil and gas fields show efficiency is only around 91 percent, scientists report in the Sept. 30 Science. Making up the difference would be the equivalent of taking nearly 3 million cars off the road. 

    The natural gas escaping is primarily methane. This greenhouse gas lingers for only nine to 10 years in the atmosphere, but its warming potential is 80 times that of carbon dioxide. So oil and gas companies light flares — burning the methane to produce less-potent carbon dioxide and water. The industry and the U.S. government assumed those flares worked at 98 percent efficiency. But previous studies said that might be too optimistic, says Genevieve Plant, an atmospheric scientist at the University of Michigan in Ann Arbor (SN: 4/22/20).

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    Plant and her colleagues sent planes to sample air over more than 300 flares in the Bakken Basin in North Dakota and the Permian and Eagle Ford basins in Texas, which account for more than 80 percent of the flaring in the country. The samples showed five times as much methane unburned than previously estimated.

    The drop from 98 to 91 percent efficiency might seem small, but the effects are large, says Dan Cusworth, an atmospheric scientist at the University of Arizona in Tucson who was not involved in the study. “Any percentage that is in the methane phase instead of CO2 phase is substantially more problematic.”

    Half of the difference is due to flares that aren’t burning. “We expected that flares might show a range of efficiencies, but we did not expect to see so many unlit flares,” Plant says. Between 3 and 5 percent of flares weren’t working at all. If those fires were lit, and 98 percent efficiency achieved, the result could remove the equivalent of about 13 million metric tons of carbon from the atmosphere. Light ‘em up.  More