A study published in the journal Environmental Research Letters finds that five of the uninhabitated Solomon Islands have submerged underwater and six more have experienced dramatic shoreline reductions due to man-made climate change. The study by a team of Australian researchers offers scientific evidence confirming anecdotal accounts of climate change impacts on Pacific islands. That evidence consists in part of radiocarbon tree dating and of aerial and satellite images of 33 islands dating back to 1947.
According to the study authors, the Western Pacific, where residents in many remote communities must constantly climb to higher elevations, is a hotspot for tracking sea-level rise.
The Solomon Islands have experienced nearly three times the global average of sea-level rise, 7–10 millimeters per year since 1993—rates consistent with those that can be expected across much of the Pacific in the second half of this century, reported Scientific American.
Previous research had attributed Pacific island shoreline changes to a mix of extreme events, seawalls, and inappropriate coastal development as well as sea-level rise. But the new study directly links island loss to climate-related phenomena.
Human disturbances, plate tectonics, hurricanes, and waves can mask the effects of climate change. So to hone in on those effects, the researchers studied islands with no human habitation—Nuatambu Island being the one notable exception.
“Rates of shoreline recession are substantially higher in areas exposed to high wave energy, indicating a synergistic interaction between sea-level rise and waves,” the study authors said. “Understanding these local factors that increase the susceptibility of islands to coastal erosion is critical to guide adaptation responses for these remote Pacific communities.”
U.S. Energy-Related Carbon Dioxide Emissions Fall But Global CO2 Concentrations Rise
The Energy Information Administration (EIA), which released the data, attributed the decline largely to “decreased use of coal and the increased use of natural gas for electricity generation.” Such fuel use changes, the EIA reports, accounted for 68 percent of total energy-related carbon dioxide reductions from 2005 to 2015.
Meanwhile, carbon dioxide concentrations at a remote Australia monitoring station—Cape Grim—are poised to hit a new high of 400 parts per million (ppm) of carbon dioxide for the first time in a few weeks. Though that mark is largely symbolic, the United Nations suggests that concentrations of all greenhouse gases should not be allowed to peak higher than 450 ppm this century to maximize chances of limiting global temperature rise.
“We wouldn’t have expected to reach the 400 ppm mark so early,” said David Etheridge, an atmospheric scientist with Commonwealth Scientific and Industrial Research Organisation (CSIRO), which runs the station. “With El Nino, the ocean essentially caps off its ability to take up heat so the concentrations are growing fast as warmer land areas release carbon. So we would have otherwise expected it to happen later in the year.”
The first 400 ppm milestone was hit in 2013 by a monitoring station in Mauna Loa. Cape Grim and Mauna Loa are among the stations that measure baseline carbon dioxide across the world. Their readings are unaffected by regional pollutions sources that would contaminate air quality.
Companies Relinquish Arctic Drilling Leases
The region is estimated to hold 27 billion barrels of oil and 132 trillion cubic feet of natural gas, but tapping these resources has come at great risk for companies.
“Given the current environment, our prospects in the Chukchi Sea are not competitive within our portfolio,” said ConocoPhillips spokeswoman Natalie Lowman. “This will effectively eliminate any near-term plans for Chukchi exploration for the company.”
Marketplace reports that data secured through a Freedom of Information Act request revealed that Shell, ConocoPhillips, Eni and Iona Energy have renounced all but one of their leases in the Chukchi Sea—meaning 80 percent of all area in the American Arctic leased in a 2008 sale has or will be abandoned.
Shell Spokesman Curtis Smith said “After extensive consideration and evaluation, Shell will relinquish all but one of its federal offshore leases in Alaska’s Chukchi Sea. Separate evaluations are underway for our federal offshore leases in the Beaufort Sea. This action is consistent with our earlier decision not to explore offshore Alaska for the foreseeable future.”
The Climate Post offers a rundown of the week in climate and energy news. It is produced each Thursday by Duke University’s Nicholas Institute for Environmental Policy Solutions.
Limiting global average temperature increase to “well below” 2 degrees Celsius above pre-industrial levels and to pursue efforts to limit that increase to 1.5 degrees Celsius—as agreed at the United Nations Climate Change Conference in Paris last year—will do little to stop portions of the world from becoming uninhabitable.
That’s according to a new study published in the journal Climatic Change, which compares data from 1986 to 2005 with predictions from 26 climate models over the same period to project climate conditions for two future periods—2046 to 2065 and 2081 to 2100. In both cases, the highest temperature rise is predicted in summer in the Middle East and North Africa. By 2050, both study projections find the global temperature will be close to or have exceeded the 2 degree Celsius target.
“We have been investigating environmental issues, especially airborne dust, air quality and climate change, in the Middle East for many years,” said Jos Lelieveld of the Max Planck Institute for Chemistry and study co-author. “Recently, we ‘expanded’ our interest to include North Africa, and discovered the important role of desert warming amplification in summer. It is evident that this can affect human habitability in the entire region. Since the Middle East and North Africa are troubled by many unfortunate developments, exceedingly hot summers can be expected to exacerbate problems.”
A separate study by the World Bank suggests that the Middle East, North Africa, and central and South Asia could suffer large economic hits due to water scarcity associated with climate change. These regions could see their growth rates decline by as much as 6 percent of GDP by 2050 due to water-related impacts on agriculture, health and incomes.
“When we look at any of the major impacts of climate change, they one way or another come through water,” said Richard Damania, lead author of the report. “So it will be no exaggeration to claim that climate change is really in fact about hydrological change.”
To mitigate the impact of climate change on water supplies, the report suggests better planning for water resource allocation, adoption of incentives to increase water efficiency and investments in infrastructure for more secure water supplies and availability.
As Ocean Temps Rise, Ocean Oxygen Decreases
According to a new study in the journal Global Biogeochemical Cycles, ocean oxygen levels are decreasing due to climate change—with grave consequences for oxygen-reliant sea life such as crabs, squids, and many kinds of fish. The authors say the deoxygenation effect is already detectable in the southern Indian Ocean and parts of the eastern tropical Pacific and the Atlantic.
“Loss of oxygen in the ocean is one of the serious side effects of a warming atmosphere, and a major threat to marine life,” said lead author Matthew Long, a researcher at the National Center for Atmospheric Research (NCAR).
The study uses a climate change model to attempt to determine precisely when ocean “deoxygenation” can be attributed to human-induced climate change, suggesting that differentiating between climate change-related losses and natural fluctuations will become increasingly less difficult. It predicts that by the 2030s, climate-change-related oxygen losses will be pervasive and obvious if greenhouse gas emissions continue unchecked. By the year 2100, it says, a significant fraction of the world’s oceans will experience some deoxygenation due to human activity.
“Since oxygen concentrations in the ocean naturally vary depending on variations in winds and temperature at the surface, it’s been challenging to attribute any deoxygenation to climate change,” Long said. “This new study tells us when we can expect the effect from climate change to overwhelm the natural variability.”
As seas warm, their capacity to absorb oxygen at the surface decreases, along with water turnover, which in turn decreases the chances that oxygen at the surface will move under the surface. That’s because as water heats, it expands and becomes lighter than the water beneath it and therefore less likely to sink. The low oxygen levels can create dead zones.
Florida Keys Coral Reefs Reach Climate-Related ‘Tipping Point’
Two weeks after the world learned that 93 percent of Australia’s Great Barrier Reef has been bleached comes word of damage to reefs around South Florida and the Keys as a result of ocean acidification linked to warming waters. According to research in the journal Global Biogeochemical Cycles, reefs in the upper Florida Keys may be losing more limestone than they create each year—a “tipping point” that was projected for 2050 (subscription).
“These bleaching events are an acute problem caused by hot weather spells,” said study co-author Chris Langdon, a professor at the University of Miami’s Rosenstiel School of Marine and Atmospheric Science. “Acidification is chronic; it lasts 365 days out of the year. This is one reason we have to reduce carbon dioxide emissions sooner than later.”
Typically, conditions in the ocean, such as water temperature and light, are favorable for the growth of coral limestone in spring and summer and are less favorable in fall and winter. As oceans absorb atmospheric carbon dioxide and ocean pH decreases, the natural summer growth cycle of coral decreases such that the effects of coral dissolution from ocean acidification cannot be offset.
The study findings are based on water samples taken along the 124-mile stretch of the Florida Reef Tract north of Biscayne National Park to the Looe Key National Marine Sanctuary. Because the data were collected in 2009 and 2010, the researchers suggest that another analysis should be conducted.
“The worst bleaching years on record in the Florida Keys were 2014–2015, so there’s a chance the reefs could be worse now,” said Langdon.
The Climate Post offers a rundown of the week in climate and energy news. It is produced each Thursday by Duke University’s Nicholas Institute for Environmental Policy Solutions.
Last week more than 150 nations signed the Paris Agreement, pledging to hold the increase in the global average temperature to well below 2 degrees Celsius above pre-industrial levels and to pursue efforts to limit the temperature increase to 1.5 degrees Celsius. Now, the first comprehensive analysis of the impacts of that half centigrade difference has been published in the journal Earth System Dynamics. The scientists found the additional 0.5 degrees Celsius would lead to longer heatwaves—“the difference between events at the upper limit of present-day natural variability and a new climate regime”—as well as more severe droughts and, in the tropics, decreased crop yield and the potential demise of all coral reefs. The extra 0.5 degrees Celsius could also mean that global sea levels rise 10 centimeters more by 2100.
“We found significant differences for all the impacts we considered,” says the study’s lead author Carl Schleussner, a scientific advisor at Climate Analytics in Germany.
The researchers analyzed climate models used in the Intergovernmental Panel on Climate Change Fifth Assessment Report, which focused on the projected regional impacts of 1.5 degrees Celsius and 2 degrees Celsius of warming, and considered 11 indicators, including extreme weather events, water availability, crop yields, coral reef degradation and sea-level rise.
They found that projected climate impacts at a 2 degrees Celsius increase are significantly more severe than at a 1.5 degrees Celsius increase in some regions. In the Mediterranean, for example, fresh-water availability by 2100 would be some 10 percent lower in a 1.5 degrees Celsius world and 17 percent lower in a 2 degrees Celsius world. In Central America and West Africa, the half-degree difference could reduce maize and wheat yields by twice as much. Tropical regions would bear the brunt of the impacts of an additional half degree of warming, experiencing heat waves at about twice the global rate. Those events could last up to three months at 2 degrees Celsius, compared with two months at 1.5 degrees Celsius, the researchers say.
Tropical coral reefs are particularly sensitive to the half degree increase. By 2100, some reefs might adapt to 1.5 degrees Celsius of warming, but the larger increase would put nearly all of them at risk of severe degradation from coral bleaching.
EPA Moves Forward with Clean Energy Incentives Program
The U.S. Environmental Protection Agency (EPA) has sent a proposal on the Clean Energy Incentive Program (CEIP), an optional program included in the Clean Power Plan that rewards states for early investment in certain renewable energy or energy efficiency projects in 2020 and 2021, to the Office of Management and Budget for review. The move is the final step before the CEIP can be formally proposed to the public (subscription).
The EPA released details on the draft CEIP as part of the final Clean Power Plan—the Obama administration’s rule to limit greenhouse gas emissions from the existing fleet of fossil fuel-fired power plants—in August. But, earlier this year, the Supreme Court issued a stay of the Clean Power Plan.
“Many states and tribes have indicated that they plan to move forward voluntarily to work to cut carbon pollution from power plants and have asked the agency to continue providing support and developing tools that may support those efforts, including the CEIP,” the EPA said. “Sending this proposal to OMB for review is a routine step and it is consistent with the Supreme Court stay of the Clean Power Plan.”
Pleasant Weather Affecting Americans’ View of Climate Change
A new study in the journal Nature finds that 80 percent of Americans live in counties where the weather is more pleasant than four decades ago. This mild temperature trend, the study says, is increasingly preferred, lessening many Americans’ concern about climate change.
“Rising temperatures are ominous symptoms of global climate change, but Americans are experiencing them at times of the year when warmer days are welcomed,” said study co-author Patrick J. Egan, an associate professor at New York University’s Wilf Family Department of Politics. He adds that “whereas weather patterns in recent decades have served as a poor source of motivation for Americans to demand a policy response to climate change, public concern may rise once people’s everyday experiences of climate change effects start to become less pleasant.”
Conducted by New York and Duke universities, the study examined each county in every U.S. state from 1974 to 2013—assessing the mildness of winters, rainfall averages, and humidity and heat intensity during summer months. It found that 99 percent of Americans live in places where the average January temperature increased.
“Here in the U.S., when we’re experiencing ice storms, the idea of a 1.5 or 2 degree rise might sound like good news,” said Megan Mullin, associate professor of environmental politics at Duke University. As a result, she said, scientists need to reconsider their messages.
The Climate Post offers a rundown of the week in climate and energy news. It is produced each Thursday by Duke University’s Nicholas Institute for Environmental Policy Solutions.
Four months after it was finalized by delegates to the Paris Climate Change Conference, the Paris Agreement will be signed by more than 100 nations on Friday. While the agreement is facially insufficient to meet its overall emissions objectives, the signing of the Paris agreement nevertheless is significant. It brings into effect the approach and policy infrastructure needed to tackle the United Nations Framework Convention on Climate Change’s ambitious goal to minimize human-caused climate change. The agreement does not solve the problem on its own, but it is a structured revisitation of the science and national commitments that provide the adaptive approach necessary to reach a solution. It is now on researchers and entrepreneurs to invent solutions; for governments, development banks and the private sector to deploy them; and for nations to hold each other accountable as this agreement goes into effect.
Energy innovation is just one of the benefits of the signing, according to White House Press Secretary Josh Earnest.
“This will open up a market for energy innovation that U.S. companies have pioneered,” Earnest said. “This is going to open up a global market for the kind of renewable energy technology that U.S. companies are at the cutting edge of.”
Other shifts have occurred since the Paris Agreement was finalized, GreenBiz reports. Big companies have backed the Clean Power Plan, there’s a rise in “sub-national” climate action at the state and city level and President Obama has proposed $10-a-barrel-tax on oil, they say.
EPA Finds Benefits Outweigh Cost of Mercury Rule
Benefits of the Mercury and Air Toxics Standard (MATS) rule outweigh cost, the U.S. Environmental Protection Agency (EPA) said in findings released in defense of its issuance of the first-ever federal regulations requiring power plants to cut mercury emissions and other toxics.
The Supreme Court found, last year, that the EPA should have considered compliance costs when determining whether it was “appropriate and necessary” to regulate mercury emissions from the power sector. In a June ruling, it did not strike down the regulation; rather, it required the EPA to take costs into consideration.
In its final 167-page report on the matter, now awaiting publication in the Federal Register, the EPA details how it considered cost in evaluating whether to regulate coal-and oil-fired power plants under the Clean Air Act (subscription).
“Based on this analysis, EPA has determined that the cost of complying with MATS, whether assessed as a percentage of total capital expenditures, percentage of power sector sales, or predicted impact on the retail price of electricity, is reasonable and that the electric power industry can comply with MATS and maintain its ability to provide reliable electric power to consumers at a reasonable cost,” the EPA wrote.
The annual cost of complying with MATS, the EPA found, amounts to between 2.7 and 3.5 percent of electricity sales, and the capital costs between 3 and 5.9 percent of annual power sector capital expenditures over 10 years.
Methane Emissions Greater Than Thought
In its newly released annual greenhouse gas emissions inventory, the EPA raised its estimate of total U.S. methane emissions in 2013 by 13 percent—an increase of more than 3.4 million metric tons and a long-term global warming impact of a year’s worth of emissions from some 20 million cars, Science News reported. The agency’s first estimate of methane emissions for 2014 is even higher, although only slightly so—29.233 million metric tons compared with 28.859 million metric tons.
Although there was a roughly 1 percent increase in total U.S. greenhouse gas emissions between 2013 and 2014, the inventory shows 2014 levels were 8.6 percent lower than 2005 levels, taking into account carbon sinks (subscription).
According to the EPA, the biggest methane emitter is the oil and natural gas industry—not animals like cattle and other livestock, as had been suggested by last year’s inventory. The data in this latest inventory are based on new techniques for estimating methane leaking from valves, compressors, vents, and other oil and gas equipment.
Scientists have warned that severe drought and precipitation are among the risks of greenhouse-gas-induced climate change, but a study published in the journal Nature finds that extremely warm temperatures do not always translate into record wet and dry extremes. Highlighting the complexities in predicting the effects of planetary warming on precipitation, lead author Fredrik Ljungqvist of Stockholm University said that more dramatic wet-dry weather extremes had occurred in centuries cooler than the 20th century.
“Several other centuries show stronger and more widespread extremes,” he said. “We can’t say it’s more extreme now.”
In this first hemispheric-scale, centuries-long water availability assessment, the researchers statistically analyzed evidence for changes in precipitation and drought, compiling hundreds of precipitation records across the Northern Hemisphere from historical accounts as well as archives on such things as tree-rings and lake sediments.
They detected a pattern of alternating moisture regimes throughout the last 12 centuries, suggesting that “the instrumental period is too short to capture the full range of natural hydroclimate variability.”
Their finding that the last century’s temperature rise may not have affected the hydroclimate as much as previously thought challenges the conclusions of the United Nations Intergovernmental Panel on Climate Change.
In a News and Views article published in Nature, Matthew Kirby of California State University at Fullerton suggested that current climate models should not be discarded because their results, which indicate that “dry gets dryer and wet gets wetter,” do not match the Ljungqvist team’s proxy results, which indicate no difference in the water dynamics of the 20th century and those of the pre-industrial era.
“Do their results invalidate current predictive models?” Kirby asked. “Certainly not. But they do highlight a big challenge for climate modellers, and present major research opportunities both for modellers and for climate scientists who work with proxy data.”
Study: Climate Change Causing Earth to Shift
A study published in the journal Science Advances reveals that climate change affects how Earth tilts on its axis. Although scientists have known that Earth’s spin axis has been drifting due to ice cap melt in Greenland and Antarctica, the new research suggests that changes in terrestrial water storage also play a role in the planet’s decadal axis swings. The finding is based on data collected from NASA’s Gravity Recovery and Climate Experiment (GRACE) satellite, which can detect changes in the mass of Earth’s ice sheets and oceans.
Before 2000, Earth’s spin axis was moving westward toward Canada, but since then, climate-change-driven ice loss has pulled the direction of drift eastward approximately seven inches a year—a shift that lead researcher Surendra Adhikari of NASA’s Jet Propulsion Laboratory described as “very dramatic” and that scientists say is meaningful.
“This is the first time we have solid evidence that changes in land water distribution on a global scale also shift which direction the axis moves to,” said Adhikari.
Although the study data doesn’t indicate whether the most recent shift in the pole is the result of human activities, the study authors think they will be able to use them to tease out man-made climate change later this year. Because polar motion and climate variability appear to be linked, scientists can examine historical records of the pole’s motion in relation to changes in Earth’s climate. If those changes are less dramatic than the ones evidenced today, scientists could assert that global warming has a controlling influence on Earth’s poles.
U.N. Climate Agreement Terms Studied, Launch Pegged Early
Next week on Earth Day (April 22), 130 countries are expected to sign the Paris Climate Agreement, which has a goal of limiting average surface temperatures to “well below” 2 degrees Celsius. But already the United Nations Intergovernmental Panel on Climate Change is looking into the feasibility of what U.N. Climate Chief Christiana Figueres describes as “a moonshot”: limiting global emissions to 1.5 degrees Celsius.
Figueres believes the Paris agreement will take effect in 2018—two years sooner than currently slated.
The agreement will come into force once 55 parties representing 55 percent of the world’s total emissions have both signed and ratified it.
A study published in Nature finds that Antarctic ice-sheet collapse driven by greenhouse gas emissions could double the sea-level rise predicted for this century—from 3.2 feet according to a three-year-old United Nations estimate to upward of 6.5 feet by 2100. The research builds on the work of other recent studies pointing to an irreversible melting of the West Antarctic Ice Sheet as a result of human-caused climate change, but it suggests that sea-level rise could shift into high gear, becoming an existential problem for low-lying coastal cities within the lifespan of current generations of people absent rapid emissions cuts to contain warming to within 2 degrees Celsius above pre-industrial levels.
The study findings are based on new computer simulations showing that warming of the atmosphere and the oceans makes the ice sheet vulnerable from above and below. By the 2050s, according to the simulations, the ice sheet would begin disintegrating, and parts of the higher, colder ice sheet of the East Antarctica would also eventually fall apart.
The climate model developed by the study authors accounts for ice loss through complex processes, including “hydro fracturing,” a process whereby meltwater on ice shelves causes huge chunks of ice to fall into the water. By reflecting these processes, the researchers were able to simulate past geological periods in which sea levels were higher than today but carbon dioxide levels were about the same or even much lower. They projected sea-level rise using versions of their model that best simulated these periods—the first model to do so.
Why is reconstruction of past rises in sea level important? High sea levels during warm intervals, such as the Pliocene and Eemian eras, imply that the Antarctic Ice Sheet is highly sensitive to climate warming.
“In the past, when global average temperatures were only slightly warmer than today, sea levels were much higher,” said study co-author Rob DeConto, a geoscientist at the University of Massachusetts Amherst. “At the high end, the worst-case scenarios, with sort of business as usual greenhouse gas emissions … we will literally be remapping coastlines. North America is kind of a bull’s eye for impacts of sea level rise if it’s the west Antarctic part of Antarctica that loses the ice first. That’s the place that we’re worried about losing ice first.”
Study: Health Impacts of Climate Change Significant
The public health impacts of climate change on people in the United States will be significant and wide ranging, according to a study by the U.S. Global Change Research Program. The study reflects data and analysis from eight agencies, led by the U.S. Environmental Protection Agency (EPA), the Department of Health and Human Services, and the National Oceanic and Atmospheric Administration, which said that “Nearly all of the health threats, from increases in our exposure to excessive heat to more frequent, severe or longer-lasting extreme weather events to degraded air quality to diseases transmitted through food, water, and vectors (such as ticks and mosquitoes)—even stresses to our mental health—are expected to worsen.”
Without rapid efforts to combat climate change, extreme heat alone will cause more than 11,000 additional deaths in the summer of 2030, the study suggests. Other risks include worsening allergy and asthma conditions and increased exposure of food to certain pathogens and toxins. But climate change will not just exacerbate existing risks—it will give rise to unprecedented health problems such as the spread of Lyme disease in new locations.
“Every American is vulnerable to the health impacts associated with climate change,” said White House Science Adviser John Holdren, adding that “Some are more vulnerable than others.”
These groups include pregnant women, children, the elderly, low-income people, communities of color and those with disabilities or pre-existing medical conditions.
Release of the findings coincided with the Obama administration’s announcement of several new initiatives to address those impacts, such as expanding the scope of a presidential task force on childhood risks to include climate change (subscription). Other actions include creating climate change and health curricula for schools and establishing a Climate-Ready Tribes and Territories Initiative, which will provide funding for prevention of climate-change-related health problems.
Paris Deal: Largest Polluters Agree to Sign
Last week, the White House announced that the United States and China will sign the Paris Agreement to combat global climate change at a United Nations ceremony April 22.
“Our cooperation and our joint statements were critical in arriving at the Paris agreement, and our two countries have agreed that we will not only sign the agreement on the first day possible, but we’re committing to formally join it as soon as possible this year,” said President Obama. “And we urge other countries to do the same.”
Brian Deese, senior adviser to President Obama, said swift approval of the agreement would keep emissions reductions efforts on track. Noting congressional action last year to extend tax credits for wind and solar energy and asserting firm legal ground for the Clean Power Plan, Deese said that the United States has both “the capacity and the tools” to meet its international commitments.
United Nations Secretary-General Ban Ki-moon has said that he expects at least 120 countries will sign the agreement at the April 22 ceremony at the U.N.’s New York headquarters. To enter into force, that agreement needs at least 55 countries representing at least 55 percent of global emissions to formally accede to it. So far, three Pacific island nations have ratified the deal.
Scientists at the National Snow and Ice Data Center (NSIDC) said on Monday that Arctic sea ice cover of 5.607 million square miles on March 24 represented the lowest winter maximum since records began in 1979. That’s 5,000 square miles less than last year’s record low. Contributing to the ice extent loss were record high air temperatures and relatively warm seawater.
“It is likely that we’re going to keep seeing smaller wintertime maximums in the future because in addition to a warmer atmosphere, the ocean has also warmed up,” said Walt Meier, a sea ice scientist at NASA’s Goddard Space Flight Center. “That warmer ocean will not let the ice edge expand as far south as it used to. Although the maximum reach of the sea ice can vary a lot each year depending on winter weather conditions, we’re seeing a significant downward trend, and that’s ultimately related to the warming atmosphere and oceans.”
After this winter’s record ice lows, scientists expect the Arctic could be ice-free in the summer months in the next few decades.
“Sometime in the 2030s or 2040s time frame, at least for a few days, you won’t have ice out there in the dead of summer,” said John Walsh, chief scientist of the International Arctic Research Centre. “The balance is shifting to the point where we are not going back to the old regime of the 1980s and 1990s. Every year has had less ice cover than any summer since 2007. That is nine years in a row that you would call unprecedented. When that happens you have to start thinking that something is going on that is not letting the system go back to where it used to be.”
The effects of diminishing sea ice may not be limited to just the Arctic.
“The Arctic is in crisis,” said Ted Scambos, NSIDC lead scientist. “Year by year, it’s slipping into a new state, and it’s hard to see how that won’t have an effect on weather throughout the Northern Hemisphere.”
A new paper in the Journal of Climate linked the vanishing Arctic sea ice, along with other sea ice melting and global sea-level rise, to climate change. The authors, who used computer models and field measurements to explore whether Arctic sea ice loss has contributed to melting of the Greenland ice sheet, say that melting Arctic sea ice can block cold, dry Canadian air, increasing the flow of warm, moist air over Greenland and contributing to extreme heat events and surface ice melting. If the Greenland ice sheet completely melted, the paper says, the global sea level would rise about 20 to 23 feet.
U.S. Environmental Protection Agency Files Brief Defending Clean Power Plan
The D.C. Circuit is set to begin hearing oral arguments challenging the Clean Power Plan—the Obama administration’s rule to limit greenhouse gas emissions from the existing fleet of fossil fuel-fired power plants—in June. On Monday, the U.S. Environmental Protection Agency filed its defense of the Clean Power Plan, telling the court that the rule is well within the bounds of its authority (subscription). Dozens of states and industry groups last month called the rule a “breathtaking expansion” of the power Congress gave the EPA—with the Clean Air Act—to regulate greenhouse gas emissions.
“The rule reflects the eminently reasonable exercise of EPA’s recognized statutory authority,” the EPA brief says. “It will achieve cost-effective [carbon dioxide] reductions from an industry that has already demonstrated its ability to comply with robust pollution-control standards through the same measures and flexible approaches. The rule fulfills both the letter and spirit of Congress’s direction.”
Renewable Energy Investment Outpaced Other Technologies: Study
Investment in renewable energy generation last year was higher than in new coal- and gas-fired power plants, according to a new report from the Frankfurt School-United Nations Environment Programme collaborating Centre for Climate & Sustainable Energy Finance and Bloomberg New Energy Finance (BNEF). In fact, renewables added more to global energy generation capacity than all other technologies combined—though they still only account for 10 percent of global electricity production.
“Global investment in renewables capacity hit a new record in 2015, far outpacing that in fossil fuel generating capacity despite falling oil, gas, and coal prices,” said Michael Liebreich, chair of the BNEF advisory board. “It has broadened out to a wider and wider array of developing countries, helped by sharply reduced costs and by the benefits of local power production over reliance on imported commodities.”
All investment in renewables—which includes new renewable energy capacity as well as early-stage technology, research and development—totaled $286 billion in 2015. That’s roughly 3 percent higher than the previous record set back in 2011.
Countries contributing some of the most to these numbers included China, which in 2015 invested $102.9 billion (a 17 percent increase from 2014), representing 36 percent of the global investment total; Chile ($3.4 billion, a 151 percent increase), India ($10.2 billion, a 22 percent increase), Mexico ($4 billion, a 105 percent increase) and South Africa ($4.5 billion, a 329 percent increase).
Data released last week by the National Oceanic and Atmospheric Administration (NOAA) shows that the string of monthly global heat records extended through February, when the average worldwide temperature was 2.18 degrees Fahrenheit above the 20th century average. The tenth straight record breaking month, February was the most above-normal month since meteorologists began tracking temperatures in 1880.
The nearly six-tenths of a degree margin by which it beat the old February record, set last year, had federal scientists describing temperatures as “staggering.” That margin was confirmed by the National Aeronautical and Space Administration, which uses statistical techniques different than NOAA’s, as well as a University of Alabama Huntsville team and the private Remote Sensing System team, which relies on measurements from satellites.
“Yes, of course El Niño has a hand in the February and other monthly temperatures records we’ve been observing, but not the only hand, not even the winning hand,” Jessica Blunden of NOAA’s National Center for Environmental Information told Mashable. “During the last big El Niño event of 97/98, temperatures departures from average were much lower compared with what we’re seeing now with this comparable event, which shows us that general warming is occurring over time.”
Many scientists say climate change is contributing to the recent high temperatures.
“We know that atmospheric CO2 (carbon dioxide) and other greenhouse gases are continuing to increase, so that’s contributing to climate change and rising temperatures overall,” said Heather Graven, a climate scientists at the Imperial College of London.
Another clue that rising greenhouse gases are contributing to the recent high temperatures is the location of the warmest-compared-to-average temperatures—the far northern latitudes, which are relatively unaffected by El Niño and where Arctic sea ice set a new lowest-extent record for a February. In those latitudes, including Alaska, recorded temperatures were at least 9 degrees Fahrenheit higher than average—“above the upper bounds” of NOAA’s February Global Land and Ocean Temperature Anomalies map.
Study: Carbon Dioxide Release Occurring Faster Than At Any Other Time
A new study in the journal Nature Geoscience, which comes on the heels of NOAA’s record temperature announcement, finds that humans are releasing climate-change-causing carbon dioxide 10 times faster than at any other time in the last 66 million years.
“I think to me it’s completely clear we have entered a completely new era in terms of what humans can do on this planet,” said Richard Zeebe, study co-author with the University of Hawaii at Manoa. “… If you look at the past and if you study the geologic record, every time when there was massive carbon release there were major changes on the planet and there were significant, large changes in the climate.”
To determine how carbon dioxide levels have influenced temperatures, researchers examined warming millions of years ago in the Paleocene-Eocene Thermal Maximum (PETM) by comparing carbon and oxygen tracers, called isotopes, deep in the New Jersey sea floor. PETM is thought to be a possible stand in for the potential impacts of carbon pollutions, as it refers to a period in history when the concentration of atmospheric carbon dioxide spiked. They found that 40.8 billion tons of carbon dioxide was released into the atmosphere in 2014 but that no more than 4.4 billion tons was released in the peak year during PETM.
“Because our carbon release rate is unprecedented over such a long time period in Earth’s history, it also means that we have effectively entered a ‘no-analogue’ state,” said Zeebe. “This represents a big challenge for projecting future climate changes because we have no good comparison from the past. Our results suggest that future ocean acidification and possible effects on marine calcifying organisms will be more severe than during PETM.”
Climate Change Could Be Abrupt, Trigger Dire Consequences
Burning fossil fuels at the current pace will trigger an abrupt climate shift, according to a study published in the journal Atmospheric Chemistry and Physics. Authored by retired NASA climate scientist James Hansen and 18 others, the study uses global climate modeling, paleoclimate data and modern observation of interactions between the ocean and ice sheets (specifically the Greenland and Antarctic ice shelves) to determine impacts associated with melt.
“We conclude that light freshwater added to upper layers of the ocean is already beginning to shut down North Atlantic Deep Water formation and Antarctic Bottom Water formation,” said Hansen. “This will have enormous consequences in future decades, if full shutdown is allowed to occur.”
The study, which stirred debate when it came out in draft form this summer, suggests that the impacts of global warming will not only happen more quickly than thought, but be more dire than envisioned. Holding temperatures to the 2 degrees Celsius of warming above pre-industrial levels would not be enough to save the planet from experiencing collapsing ice sheets and megastorms.
The paper concludes that “if the ocean continues to accumulate heat and increase melting of marine-terminating ice shelves of Antarctica and Greenland, a point will be reached at which it is impossible to avoid large-scale ice sheet disintegration with sea level rise of at least several meters. The economic and social cost of losing functionality of all coastal cities is practically incalculable.”
In a move that could help the United States and Canada meet pledges they made at last year’s United Nations Climate Change Conference in Paris, President Barack Obama and Canadian Prime Minister Justin Trudeau announced a plan to cut oil and gas industry methane emissions 40–45 percent, compared to 2012 levels, by 2025. In Canada, the environment ministry will work with provinces and other parties to implement national regulations by 2017; in the United States, the plan calls for the U.S. Environmental Protection Agency (EPA) to develop regulations “immediately” (subscription). Although the EPA issued a methane rule for new oil and gas sources last year, some experts and Obama administration officials believe that a regulation for existing sources is needed to meet the new reduction pledge.
EPA Administrator Gina McCarthy said the EPA will begin tackling the issue by requiring oil and gas companies to report certain data about methane output in April.
“I’m confident the end result of this effort will be a common-sense, reasonable standard to reduce methane emissions that are contributing to climate change,” she said.
New data suggests that annual releases of methane in the United States total nine million tons—much higher than previously thought.
The commitments to reduce emissions of methane by the United States and Canada were part of a joint statement in which Obama and Trudeau announced a range of environmental initiatives to combat climate change, expand renewable energy, and protect the Arctic region and in which they promised that their two countries would “play a leadership role internationally in the low carbon global economy over the coming decades.” According to the statement, Obama and Trudeau consider the agreement reached in Paris a “turning point” in global efforts to combat climate change, and they will cooperate in implementing it, committing to signing it “as soon as feasible.”
Among the announced actions, it was the plan to reduce methane—a chemical that is many more times more potent a greenhouse gas than carbon dioxide—that drew the most praise and criticism, reported the Los Angeles Times. Some representatives of the oil and gas industry said they were already taking steps to reduce methane leaks, and some environmental groups said a better solution would be to reduce fossil fuels and hydraulic fracturing, which is linked to those leaks. Other environmental groups said methane reduction delivers a nearer-term climate payoff than cutting carbon dioxide from power plants.
Sea Level Rise Big, Underestimated
A new study in the journal Nature Climate Change suggests that future sea-level increases due to climate change could displace anywhere from 4.3 to 13.1 million people in coastal communities in the U.S. by the end of the century.
“Projections are up to three times larger than current estimates, which significantly underestimate the effect of sea-level rise in the United States,” said study co-author Mathew Hauer of the University of Georgia. Why? Earlier studies don’t account for population growth.
A second study in the journal Earth System Dynamics explores the feasibility of delaying the problem of rising seas by pumping vast quantities of ocean water onto the continent of Antarctica to thicken the ice sheet by freezing the water.
“This is not a proposition,” said Anders Levermann of the Potsdam Institute for Climate Impact Research and one of the study’s co-authors. “It’s a discussion. It’s supposed to initiate the discussion on how big the sea level problem really is.”
The researchers find that it would take more than 7 percent of the global energy supply just to power the pumps needed to get the water at least 435 miles inland to the Antarctic ice sheet so it could freeze—preventing the heavy, newly formed ice sheets from sliding into the ocean. That’s just one of the many hurdles to engineering, much less financing such a project, according to the Earth System Dynamics study.
“When we stop the pumping one day, additional discharge from Antarctica will increase the rate of sea-level rise even beyond the warming-induced rate,” Levermann said. “The magnitude of sea-level rise is so enormous, it turns out it is unlikely that any engineering approach imaginable can mitigate it.”
Study Finds Connection to Climate Change for Some Extreme Weather Events
A newly released report by The National Academies of Sciences, Engineering and Medicine makes it easier to connect climate change with some extreme weather events. Published in the National Academies Press, the report indicates that we can now say more about the extent to which weather events have been intensified or weakened as a result of climate change.
“In the past, a typical climate scientist’s response to questions about climate change’s role in any given weather event was ‘we cannot attribute any single event to climate change,’” the report said. “The science has advanced to the point that this is no longer true as an unqualified blanket statement. In many cases, it is now often possible to make and defend quantitative statements about the extent to which human-induced climate change (or another casual factor, such as a specific mode of natural variability) has influenced either the magnitude or the probability of occurrence of specific types of events or event classes.”
Technology and the length of human climatic records have made “attribution science” possible, but it is still new. The Washington Post reports that temperature-related events allow for the strongest attribution statement since the “chain of causality from global warming to the event is shortest and simplest.”
Supreme Court Chief Justice John G. Roberts Jr. denied a request for a stay or injunction of the U.S. Environmental Protection Agency’s Mercury and Air Toxic Standards (MATS) rule—a rule that 20 states have claimed is “unlawful and beyond EPA’s statutory authority.” The ruling means MATS, which requires coal-burning power plants to install technologies to reduce emissions of toxic pollutants, remains in effect while the EPA continues its study of compliance costs.
The stay denial, issued solely by Chief Justice Roberts and without comment, follows a June Supreme Court decision in which five justices found that the EPA should have considered compliance costs when determining whether it was “appropriate and necessary” to regulate mercury emissions from the power sector. The June ruling did not strike down the regulation; rather, it required the EPA to take costs into consideration.
In a supplemental finding proposed in November, the EPA indicated that the costs of implementing MATS were reasonable. The EPA is expected to finalize its cost accounting, which seeks to address court concerns, in April.
“These practical and achievable standards cut harmful pollution from power plants, saving thousands of lives each year and preventing heart and asthma attacks,” said Melissa Harrison, EPA spokeswoman.
Melting of Greenland’s Ice Sheet Accelerating with Loss of Reflectivity
A study in European Geosciences Union journal The Cryosphere finds that the reflectivity, or “albedo,” of Greenland’s ice sheet could decrease by as much as 10 percent by the end of the century, potentially leading to significant sea-level rise (subscription). The study links the diminishing capacity of Greenland’s ice sheet to reflect solar radiation—so-called “darkening”—to positive feedback loops that quicken ice melt, allowing it to feed on itself.
Scientists have been aware of the feedback loops, lead author Marco Tedesco, a professor at Columbia University’s Lamont-Doherty Earth Observatory, told the Christian Science Monitor. “What’s new,” he said, “is the acceleration of the darkening, which started in 1996.”
The research used satellite photos dating back to 1981 plus a model to examine the impact of increases of both impurities in the ice, often visible to the human eye, and the size of grains in the snowpack, which is often invisible to the human eye and which makes snow “‘darker’—not dirtier, but more absorbent of energy from the sun,” said Tedesco. As snowpack melts and refreezes, meltwater binds grains together. The larger the grains, the less reflective the surface of the ice sheet and the faster the melting, which keeps speeding up as the remaining impurities become concentrated at the surface.
The study attributes the acceleration of darkening in 1996 to a change in atmospheric circulation. The North Atlantic Oscillation, a natural weather cycle, went into a phase that favored incoming solar radiation and warm, moist air from the south. Although those conditions shifted in 2013 to favor less melting, the sensitivity of the ice sheet to atmospheric air temperatures had already increased, and in 2015, melting spiked again, affecting more than half of the Greenland ice sheet.
The study rejected one prominent theory of Greenland’s darkening—namely, that worsening wildfires are releasing soot that is increasingly falling on Greenland. It finds “no statistically significant increase” in black carbon from fires in northern regions and an increase that is likely too small to matter from wildfires in temperate North America.
“Overall, what matters, it is the total amount of solar energy that the surface absorbs,” said Tedesco. “This is the real driver of melting.”
U.S. Makes First Green Climate Fund Payment
The United States has made the first payment to the United Nation’s Green Climate Fund (GCF). The $500 million payment is part of a broader $3 billion pledge to the GCF, which helps poor countries fight climate change and adopt clean energy technologies.
“With this announcement, which comes less than three months after the historic Paris climate agreement, the United States continues to demonstrate leadership in the international climate arena,” a State Department official told The Hill. “This grant is the first step toward meeting the president’s commitment of $3 billion to the GCF and shows that the United States stands squarely behind our international climate commitments.”