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.
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.
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.
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.
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).
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.
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.”
Last week, the U.S. Environmental Protection Agency (EPA) released an updated draft of its Greenhouse Gas Inventory, finding that total U.S. greenhouse gas emissions in 2014 were 6.8 billion metric tons of carbon dioxide equivalent—1 percent higher than in 2013, but 8 percent lower than the 2007 peak. The most revelatory revision: methane emissions figures for the oil and gas sector were 27 times higher than previous estimates. Over 20 years, that difference, says the Environmental Defense Fund, represents a climate impact equivalent to 200 coal-fired power plants.
News of the upward revision came amid a study from the University of California at Irvine (UCI) published in the journal Science that finds more than 100,000 tons of methane entered the atmosphere during a four-month natural gas leak in Southern California’s Aliso Canyon. Before it was plugged in February, the leak doubled methane emissions in the Los Angeles region. It is the largest methane leak in U.S. history, and it is likely to keep California from meeting its 2016 greenhouse gas emissions targets.
Methane emissions, a potent greenhouse gas with a long-term global warming potential thought to be many times that of carbon dioxide, are currently unregulated.
At the annual IHS CERAWEEK conference last week, EPA Administrator Gina McCarthy alluded to her agency’s proposal, last year, of methane leak detection and repair requirements for new oil wells. Methane emissions related to the oil and natural gas industry are “much larger than we ever anticipated,” she said. “The data confirm that we can and must do more on methane. By tackling methane emissions, we can unlock an amazing opportunity to better protect our environment for the future.”
Study Revises Carbon Budget Downward
A new study in the journal Nature Climate Change warns that the global carbon budget has been over-estimated and should be cut by at least half. In the abstract of their research, the authors state that for a greater than 66 percent chance of limiting warming below the internationally agreed temperature limit of 2 degrees Celsius relative to pre-industrial levels, “the most appropriate carbon budget estimate is 590–1,240 GtCO2 from 2015 onwards.” They conclude that global CO2 emissions must be cut quickly to keep within a 2°C-compatible budget.
“At current rates, the carbon budget would thus be exhausted in about 15 to 30 years,” said lead author Joeri Rogelj, a research scholar at the Energy Program of the International Institute for Applied Systems Analysis in Austria. “These numbers definitely indicate that we should not just sit and wait, because then the window for staying within the budget would become vanishingly small within decades.”
The study analyzes differences among widely varying estimates for a carbon budget consistent with the 2°C target, finding that a major reason for the range is due to assumptions and methodologies in previous studies. Its own estimate differs from many previous estimates in part because it accounts for methane and other greenhouse gases and not only for carbon dioxide.
Despite COP21 Deal, No Increase Expected for European Union Emissions Targets
The Paris Climate Agreement, signed at the United Nations Climate Conference last year, calls for a review of countries’ climate reduction goals in 2018, but a new document suggests the European Union (EU) may not be following that timeline (subscription).
As reported by Reuters, text prepared ahead of a Friday meeting of EU environment ministers on the Paris climate deal says the existing target—cutting emissions by at least 40 percent from 1990 levels by 2030—“is based on global projections that are in line with the medium-term ambition of the Paris Agreement.”
“We have the deal,” said EU Climate and Energy Commissioner Miguel Arias Canete. “Now we need to make it real. For the EU, this means completing the 2030 climate and energy legislation without delay, signing and ratifying the agreement as soon as possible, and continuing our leadership in the global transition to a low-carbon future.”
This calculation is based on keeping emissions levels to 2 degrees Celsius—but the agreement signed in Paris aspires to hold nations to a global temperature increase of well below this level and to pursuit of an increase limited to 1.5 degrees Celsius. In Euractiv, former chief negotiator for the Netherlands and European Union, Bert Mertz, examines whether a sub-2 degrees Celsius goal is feasible and what might be needed for the EU to meet a more aggressive 1.5 degree Celsius goal. He finds that although the current goal is derived from a long-term target of 80 percent emissions reduction compared with 1990 levels, the EU would need to strengthen that target to 95 percent emissions reductions.
It has been more than a week since the U.S. Supreme Court issued a stay of the U.S. Environmental Protection Agency’s (EPA) Clean Power Plan, and states are now beginning to indicate how they will approach the resulting uncertainty the decision brings. Although the stay removes the September deadline to submit compliance plans to the EPA, several continue to move forward. A poll by ClimateWire indicates that 20 states are pressing on with discussions about how to meet carbon emissions limits for power plans, 18 have stopped planning and nine are weighing whether to stop or slow down planning (subscription).
“The stay is just that—it’s a stay—so we need to be mindful that a potential outcome could be that the courts uphold it,” said Glade Sowards, Utah Division of Air Quality’s Clean Power Plan coordinator. “We don’t want to be caught flat footed.”
In an event hosted by the Brookings Institution on the Clean Power Plan, Nicholas Institute for Environmental Policy Solutions’ Climate and Energy Program Director Jonas Monast also pointed out to attendees that what states are coping with now is bigger than just the Clean Power Plan.
“The Clean Power Plan created a forcing mechanism to bring utility regulators and air regulators and utilities and affected stakeholders to the table to really start engaging about what we want the future of the electricity sector to be,” Monast said. He noted that discussion of that future would not necessarily be organized around the Clean Power Plan.
Study: Frequency, Intensity of Heat Waves Will Increase Due to GHG Emissions
If anthropocentric greenhouse gas (GHG) emissions continue unabated, once-every-20-years extreme heat waves—lasting three or more days—could become annual events across 60 percent of Earth’s land surface by 2075, says a study published in the journal Climatic Change. But only 18 percent of land areas might experience such yearly events by the last quarter of the century if measures to cut GHG emissions are put in place, according to authors Claudia Tebaldi of the National Center for Atmospheric Research (NCAR) and Michael Wehner of the Lawrence Berkeley National Laboratory in research that looks to quantify the benefits of avoiding extreme heat events.
The Department of Energy-funded study also suggests that by 2050 extreme heat waves would be 5.4 degrees Fahrenheit hotter than they might be today for 60 percent of land areas and nine degrees hotter for another 10 percent, with serious health impacts, particularly for the young, the old, and the sick and in places with historically little temperature variability (subscription).
“The study shows that aggressive cuts in greenhouse gas emissions will translate into sizable benefits, starting in the middle of the century, for both the number and intensity of extreme heat events,” Tebaldi said. “Even though heat waves are on the rise, we still have time to avoid a large portion of the impacts.”
The study used an NCAR climate model to examine how the odds of today’s 20-year events—those with a 5 percent chance of occurring in any given year—would change in a business-as-usual scenario and in scenarios in which emissions were cut to keep warming below 2 degrees Celsius (4 degrees Fahrenheit) of pre-industrial levels.
“Even under more dramatic mitigation scenarios . . . future heat wave frequency and intensity increase very dramatically,” Wehner said. But “we do have a choice about how dangerous the future will be.”
January Continued String of Record-Warm Months
January became the ninth consecutive record-breaking month for heat according to data released by the National Aeronautics and Space Administration (NASA). That agency, the Japan Meteorological Agency, and the National Oceanic and Atmospheric Administration, which has been keeping weather records for 137 years, agree that the month’s highs were unprecedented, Bloomberg reported. If the rest of the year is as warm as January, 2016 could top the record set in 2015.
According to NASA, last month was 2.03 degrees Fahrenheit above normal. But some parts of the Arctic had temperatures averaging as high as 23 degrees Fahrenheit above normal for the month, leading the region’s sea ice to decrease to a new record low for January. It averaged only 5.2 million square miles for the month—90,000 square miles fewer than the previous record set in 2011, according to the National Snow and Ice Data Center. Preliminary data from February indicate that Arctic sea ice continues to set daily record lows.
January’s temperature increases reflect the combination of accelerating manmade global warming and a record strong El Niño.
The outlook for U.S. Environmental Protection Agency’s (EPA) Clean Power Plan, a rule intended to limit greenhouse gas emissions from the existing fleet of fossil fuel-fired power plants, is the subject of debate after two key Supreme Court events last week.
First, on Tuesday, the U.S. Supreme Court in a 5–4 decision issued a stay, delaying the execution of the plan, pending the outcome of legal challenges. The New York Times called the decision “unprecedented,” because the Supreme Court had never before granted a request to halt a regulation before review by a federal appeals court. At a minimum, the ruling will allow states to skip the September deadline to submit compliance plans to the EPA.
A new twist on the fate of the Clean Power Plan came Saturday with the death of Supreme Court Justice Antonin Scalia—leaving the Supreme Court with eight justices split evenly between conservatives and liberals, and evenly split on the question of that week’s stay. Whether the White House or the Senate will confirm a new justice before the November 2016 Presidential election remains unclear, although political cynicism about any nominee’s chances has dominated commentary. President Obama announced plans to nominate a new justice, and Senate Republican leadership has indicated that it does not intend to confirm Obama’s candidate.
The D.C. Circuit is set to begin hearing oral arguments challenging the Clean Power Plan in June. Any ruling may be reviewed by the Supreme Court.
ClimateWire suggests three potential scenarios. For Clean Power Plan opponents, the best turn of events would be appointment of a new conservative-leaning justice, which would be made possible if the Senate successfully blocks an Obama appointee and a Republican takes the White House. Those in favor of the plan would benefit from appointment of a new liberal-leaning justice or from the court’s consideration of the plan before a new justice is confirmed.
Politics surrounding the nomination of the new justice are complicated, writes Tom Goldstein of the SCOTUS blog.
Study: More Aggressive Emissions Reductions Needed to Curb Air-Pollution-Related Deaths
A new study undertaken by the World Health Organization and presented last week at the annual meeting of the American Association for the Advancement of Science shows that 5.5 million die prematurely every year from air pollution. The authors—a team of U.S., Canadian, Chinese, and Indian scientists—said that most of the fatalities are in India and in China, where coal burning alone led to 366,000 deaths in 2013.
Researcher Qiao Ma from Tsinghua University in Beijing said coal burned for electricity was the largest polluter in China and that the country’s new targets to reduce emissions, agreed at last year’s Paris climate talks, are not sufficiently ambitious to end those deaths.
“Even in the most clean scenario in 2030,” Ma said, China’s growing and aging population will still suffer as many as 1.3 million deaths a year. “Our study highlights the urgent need for even more aggressive strategies to reduce emissions from coal and from other sectors.”
Although China halted approval of new coal mines for three years at the end of 2015 and has issued stringent requirements similar to those recently proposed in the United States for new coal-fired power plants, these and other measures may not halt increases in mortality, reported Time.
“Air pollution is the fourth highest risk factor for death globally and by far the leading environmental risk factor for disease,” said Michael Brauer of the University of British Columbia. “Reducing air pollution is an incredibly efficient way to improve the health of a population.”
Agreements Made to Expand Renewables, Reduce Emissions
Governors from 17 U.S. states signed an accord to diversify energy generation with clean energy sources, modernize their energy infrastructure and encourage clean transportation options. Home to about 40 percent of the country’s population, states signing the Governors’ Accord for a New Energy Future are California, Connecticut, Delaware, Hawaii, Iowa, Massachusetts, Michigan, Minnesota, New Hampshire, Nevada, New York, Oregon, Pennsylvania, Rhode Island, Vermont, Virginia and Washington.
“With this agreement, governors from both parties have joined together and committed themselves to a clean energy future,” said California Gov. Jerry Brown. “Our goal is to clean up the air and protect our natural resources.”
As part of the agreement, states will cooperate on planning and policies—pooling buying power to get cheaper clean-energy vehicles for state fleets and to build more energy-efficient regional electrical grids.
Also preparing for a cleaner-energy future is Fiji, which on Friday became the first country to formally approve the United Nations climate deal reached in Paris when its parliament ratified the agreement. Under its national climate action plan, the archipelago, which is vulnerable to flooding and strong tropical storms as a result of climate change, pledged to generate all its electricity from renewable sources by 2030 and to reduce its overall energy-sector emissions by 30 percent by 2030—if it receives climate finance from industrialized nations.
The U.S. Supreme Court blocked the Clean Power Plan, the U.S. Environmental Protection Agency’s rule limiting greenhouse gas emissions from the existing fleet of fossil fuel-fired power plants on Tuesday. The court, in a 5–4 decision split along party lines, put a stay on enforcement of the Clean Power Plan, which is designed to cut carbon dioxide emissions from power plants 32 percent below 2005 levels by 2030.
“We remain confident that we will prevail on the merits,” said the White House in a statement. “Even while the litigation proceeds, EPA has indicated it will work with states that choose to continue plan development and will prepare the tools those states will need.”
But others felt the move could be indicative that the Clean Power Plan will not survive legal scrutiny.
“Should the D.C. Circuit uphold the rule, I think the stay is indicative that the court is likely to want to hear this case,” said Scott Segal, a partner in Bracewell LPP’s Policy Resolution Group. “Even the most ardent supporters would have to concede that this does not bode well for the current rule.”
The EPA’s authority to regulate greenhouse gas emissions stems from the 2007 Supreme Court decision Massachusetts v. EPA, which found that carbon dioxide qualified as a “pollutant” and was subject to regulation under the Clean Air Act. But Bloomberg reported that the court’s intervention casts doubt on the legal prospects for the Clean Power Plan, which some utilities, coal miners and more than two dozen states are challenging as an overreach of the U.S. Environmental Protection Agency’s authority and an intrusion on states’ rights. The D.C. Circuit Court will review the merits of their lawsuits on June 2. The order blocks the Clean Power Plan from taking effect while legal battles play out, making a decision possibly another year or more away.
“A decision overturning the Clean Power Plan would not prevent the EPA from regulating greenhouse gas emissions under the Clean Air Act,” said Jonas Monast, director of the Climate and Energy Program at Duke’s Nicholas Institute for Environmental Policy Solutions. “That case focuses on current regulations. It does not call into questions the Supreme Court’s previous finding that greenhouse gases are pollutants under the Clean Air Act.”
De-carbonization of U.S. Power Sector Accelerated in 2015
Energy sector transitions envisioned by the U.S. Environmental Protection Agency (EPA) when it released its Clean Power Plan last year are already occurring at a faster pace than the EPA may have expected as evidenced by Bloomberg New Energy Finance’s (BNEF) 2016 Sustainable Energy in America Factbook, which called 2015 a “watershed year in the evolution of US energy.”
According to the report, coal use for electricity generation dropped from 39 percent in 2014 to 34 percent last year, while natural gas edged closer to becoming the largest source of U.S. power, accounting for some 32 percent of U.S. generation in 2015. Along with energy efficiency improvements, notable growth in renewable energy installations, and flat energy demand, that shift has major implications for greenhouse gas emissions reductions but not for consumer costs—at least so far.
“We saw natural gas and coal each provide about one third of U.S. electricity, and this was the smallest contribution we’ve seen from coal within the modern era,” said Colleen Regan, BNEF’s senior analyst for North American power. She noted that the decrease in coal use was attributable not only to cheap gas but also to 14 gigawatts’ worth of coal plant retirements—5 percent of U.S. coal capacity—last year.
Meanwhile, the U.S. renewable energy industry brought online 16 gigawatts of clean energy—68 percent of all new installed capacity—helping drop U.S. energy sector carbon dioxide emissions to their lowest annual level since the mid-1990s in a year that saw retail electric rates fall 1.3 percent in real terms from 2014.
Driving what the report authors suggest is a permanent shift in the U.S. energy sector are technological revolutions in the gas industry, increasingly attractive economics for renewables, and international- and national-level policy directives, including the Clean Power Plan and recent extensions of the investment tax credit for solar power and the production tax credit for wind energy (subscription).
Next Few Decades’ Emissions Trajectory Could Affect Earth for Millennia
A group of 22 researchers, including several of the world’s foremost climate scientists, contend that we have been thinking about climate change far too narrowly by making projections only to the year 2100. In a study published in Nature Climate Change, the group suggests that policy makers should consider the consequences of human emissions on global temperatures and sea level over a far longer time horizon.
“The twentieth and twenty-first centuries, a period during which the overwhelming majority of human-caused carbon emissions are likely to occur, need to be placed into a long-term context that includes the past 20 millennia, when the last Ice Age ended and human civilization developed, and the next ten millennia, over which time the projected impacts of anthropogenic climate change will grow and persist,” they write. “This long-term perspective illustrates that policy decisions made in the next few years to decades will have profound impacts on global climate, ecosystems and human societies—not just for this century, but for the next ten millennia and beyond.”
The study, which looked at climate data from the past 20,000 years and four emissions scenarios for the period 2000 to 2300, demonstrates the effects of near-term policy decisions on the climate system’s inherent lag effects—namely, the high temperature sensitivity of global ice sheets and the centuries-long atmospheric retention of carbon dioxide.
“If carbon dioxide emissions continue unchecked, the carbon dioxide released during this century will commit Earth and its residents to an entirely new climate regime,” the study says.
Report co-author, Thomas Stocker, a climate scientist at the University of Bern, put the long-term view of human emissions bluntly, saying that it sends a “chilling message” about the fossil fuel era’s risks and consequences. “It will commit us to massive adaptation efforts so that for many, dislocation and migration becomes the only option.” The study notes that even if warming falls below the United Nations target of 2 degrees Celsius, 20 percent of the world’s population must migrate away from coasts.