Humans Implicated in String of Record-Warmth Years

The Nicholas Institute for Environmental Policy Solutions at Duke University
The Nicholas Institute for Environmental Policy Solutions at Duke University

Human activities are the cause of this century’s record warm years, according to a study in the journal Scientific Reports.

“We find that individual record years and the observed runs of record-setting temperatures were extremely unlikely to have occurred in the absence of human-caused climate change,” the authors say. “These same record temperatures were, by contrast, quite likely to have occurred in the presence of anthropogenic climate forcing.”

The study, written before the release of 2015 temperature data, put the odds between 1 in 770 and 1 in 10,000 that 13 of the 15 warmest years spanning from 2000 to 2014 happened without human influence (subscription). With the inclusion of 2015 temperature data, the group’s computer simulations widened those odds to between 1 in 1,250 and 1 in 13,000, lead author Michael Mann, a professor of meteorology at Pennsylvania State University, told Reuters.

“Climate change is real, human-caused and no longer subtle—we’re seeing it play out before our eyes,” Mann said.

Mann and his co-authors ran statistical analyses of real-world measurements and comprehensive computer simulations of the climate system to distinguish human-caused climate change from natural climate variability, such as that triggered by volcanic eruptions and shifts in the sun’s output.

“2015 is again the warmest year on record, and this can hardly be by chance,” Stefan Rahmstorf, a co-author from the Potsdam Institute of Climate Impact in Germany, said. “Natural climate variations just can’t explain the observed recent global heat records, but man-made global warming can.”

Study: Low Electricity Costs and Low Emissions Not Mutually Exclusive

A new study by National Oceanic and Atmospheric Administration (NOAA) and University of Colorado Boulder researchers in the journal Nature Climate Change finds that the United States could reduce carbon dioxide emissions from electricity generation (using future anticipated costs for wind and solar) by more than 75 percent relative to 1990 levels by 2030 at approximately the same cost as 2012. The key? Using new high-voltage power lines to move renewables nationwide, eliminating the need to add new fossil fuel storage capacity.

“What the model suggests is we can get a long way, and wind and solar and natural gas can be a bridge,” said Christopher Clack of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado Boulder. “There is a path that could be possible to achieve those goals, and it doesn’t necessarily need to drive up costs.”

Using NOAA’s high-resolution meteorological data, the researchers built a model to evaluate future cost, demand, generation, and transmission scenarios and found that with improvements in transmission infrastructure, the wind and the sun could supply most of the nation’s electricity at costs comparable to today’s.

“The model relentlessly seeks the lowest-cost energy, whatever constraints are applied,” Clack said. “And it always installs more renewable energy on the grid than exists today.”

In the expected future scenario—in which renewable energy costs continue to fall while natural gas costs rise—the model predicted that the power sector could cut emissions 78 percent compared with 1990 levels at an electricity cost of 10 cents per kilowatt-hour, up from 9.4 cents in 2012 (subscription). That finding is predicated on creation of a new high-voltage direct-current (HVDC) transmission grid, which according to the authors lowers the chance of energy losses, reducing utilities’ need to amass reserves of excess capacity through natural-gas-powered generators.

“With an ‘interstate for electrons,’ renewable energy could be delivered anywhere in the country while emissions plummet,” said Alexander MacDonald, co-lead author and former director of NOAA’s Earth System Research Laboratory. “An HVDC grid would create a national electricity market in which all types of generation, including low-carbon sources, compete on a cost basis. The surprise was how dominant wind and solar could be.”

Update to Social Cost of Carbon Unnecessary

A new interim report from the National Academies of Sciences, Engineering and Medicine suggests that there is little benefit to updating estimates of the social cost of carbon in the near term. Written by a 13-member expert panel, the report recommends ways to change federal technical support documents on the social cost of carbon to enhance estimates.

“We recommended against a near-term update to the social cost of carbon” based off the IPCC report’s finding, said Richard Newell of Duke University. Newell co-chaired the panel, which includes Sanford School Professor and Nicholas Institute for Environmental Policy Solutions Faculty Fellow Billy Pizer.

To set an efficient market price on carbon emissions, it’s helpful to know the social cost of those emissions—that is, the estimate of the economic damages (in dollars) associated with an increase in carbon dioxide emissions, usually one metric ton, in a given year. The last revised estimate, in 2015, was $36 per metric ton of carbon dioxide.

A final report will examine potential approaches for a more comprehensive update to social cost of carbon estimates and is expected in early 2017.

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.

Climate Change Tops WEF Risk Ranking

The Nicholas Institute for Environmental Policy Solutions at Duke University
The Nicholas Institute for Environmental Policy Solutions at Duke University

For the first time, the World Economic Forum (WEF) has ranked an environmental risk—climate change—as the most severe economic risk facing the world. Global Risks Report 2016 says climate change is compounding and intensifying other social, economic, and humanitarian stresses such as mass migration, which it ranked as the threat most likely to materialize in the next 18 months.

“Climate change is exacerbating more risks than ever before in terms of water crises, food shortages, constrained economic growth, weaker societal cohesion and increased security risks,” said Cecilia Reyes, chief risk officer of Zurich Insurance Groups, one of the report collaborators.

Along with interaction with other risks, Margareta Drzeniek-Hanouz, head of global competitiveness and risks at the WEF, pointed to recent weather events and the frequency of natural disasters as justification for climate change’s top ranking this year. “We do see more severe and more likely weather events,” she said. “There are more droughts and floods. We have a higher and higher assessment of climate change.”

Among the priority actions outlined in the report: modifying financial systems to “unleash climate-resilient, low-carbon investments.” The authors found that incentives for such investments have yet to be incorporated into financial decision making despite increasing recognition of climate-change-related economic risks.

The report is based on a survey of 750 experts from economic, environmental, geopolitical, societal, and tech sectors about the perceived impact and likelihood of 29 prevalent global risks over a 10-year period.

Study: Rate of Man-Made Heat Energy Absorbed by Oceans Has Doubled

new study in the journal Nature Climate Change finds that since 1997 heat uptake by the world’s oceans has nearly doubled by comparison with that uptake in the previous industrial era and that heat is mixing into deeper ocean layers, rather than remaining near the surface.

The study tracked how much man-made heat energy has been buried in the oceans in the past 150 years using ocean-observing data dating as far back as the 1870s. It included readings from high-tech underwater monitors and results of computer models.

Oceans absorb more than 90 percent of man-made heat energy. Since the industrial revolution, deepwater heat content has increased by “several tenths of a degree” when averaged out across the globe, according to Peter Gleckler, the study’s lead author. Although that energy is equivalent to less than 0.5 Celsius of warming averaged across the upper reaches of the ocean, Gleckler said it is still a “huge increase,” adding that “if we want to really understand how much heat is being trapped, we can’t just look at the upper ocean anymore, we need to look deeper.”

The study found that a third of the recent ocean heat buildup occurred at depths of 700 meters or greater, possibly explaining a pause in warming at the sea surface since the end of the 20th century. Why deeper waters may be absorbing greater amounts of heat is not fully understood, according to the study.

The University of California reported that the Nature Climate Change study “found that estimates of ocean warming over a range of times and depths are consistent with results from the latest generation of climate models, building confidence that the climate models are providing useful information.”

Official Numbers: 2015 Was the Hottest Year

Independent analyses by the National Oceanic and Atmospheric Administration (NOAA), the Goddard Institute for Space Studies at the National Aeronautics and Space Administration (NASA), and the U.K. Met Office found that Earth’s surface temperatures were the warmest they have been since record-keeping began.

NASA calculated the rise at 0.23 degree Fahrenheit above 2014 and suggested that 1998 was the only year that a new record was greater than the old record by such a large margin. NOAA put the increase at 0.29 degree Fahrenheit. The U.K. Met Office expects 2016 to set another record.

“A lot of times, you actually look at these numbers, when you break a record, you break it by a few hundredths of a degree,” said Thomas Karl, director of NOAA’s National Centers for Environmental Information. “But this record, we literally smashed. It was over a quarter of a degree Fahrenheit, and that’s a lot for the global temperature.”

Although 2015 temperatures were assisted by an ongoing El Nino weather pattern—which brings heat from the Pacific Ocean into the atmosphere, Gavin Schmidt, director of NASA’s Goddard Institute for Space Studies said “it is the cumulative effect of the long-term trend that has resulted in the record warming that we are seeing.”

NASA used surface temperature measurements from more than 6,000 weather and research stations as well as ship- and buoy-based observations of sea surface temperatures for its analysis. NOAA uses similar temperature data, but it also uses different baseline periods and methods.

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.

Climate and Energy of Focus in Obama’s Final State of the Union

The Nicholas Institute for Environmental Policy Solutions at Duke University
The Nicholas Institute for Environmental Policy Solutions at Duke University

President Obama laid out four big questions the United States has to answer in his nearly hour-long final State of the Union address Tuesday night. One of those four points: How do we make technology work for us, and not against us, especially when it comes to solving urgent issues like climate change?

In discussing the role American needs to take in combating this issue, Obama highlighted America’s past willingness to rely on science.

“Sixty years ago, when the Russians beat us into space, we didn’t deny Sputnik was up there,” Obama said. “We didn’t argue about the science, or shrink our research and development budget. We built a space program almost overnight, and twelve years later, we were walking on the moon … Look, if anybody still wants to dispute the science around climate change, have at it. You’ll be pretty lonely, because you’ll be debating our military, most of America’s business leaders, the majority of the American people, almost the entire scientific community, and 200 nations around the world who agree it’s a problem and intend to solve it.”

The administration’s push to continue making new discoveries came in a speech optimistic about America’s destiny and referencing the president’s accomplishments in office the last seven years.

Obama also presented a vision for our energy future.

“Now we’ve got to accelerate the transition away from dirty energy,” he said. “Rather than subsidize the past, we should invest in the future—especially in communities that rely on fossil fuels. That’s why I’m going to push to change the way we manage our oil and coal resources, so that they better reflect the costs they impose on taxpayers and our planet. That way, we put money back into those communities and put tens of thousands of Americans to work building a 21st century transportation system.”

“None of this will happen overnight, and yes, there are plenty of entrenched interests who want to protect the status quo,” he added. “But the jobs we’ll create, the money we’ll save, and the planet we’ll preserve—that’s the kind of future our kids and grandkids deserve. And it’s within our grasp.”

McCarthy Talks Environmental Priorities in 2016

U.S. Environmental Protection Agency Administrator Gina McCarthy told the Washington Post that the Obama administration is preparing an ambitious agenda on climate change in 2016, citing new efforts to lower air pollution and a predication that the administration’s Clean Power Plan would survive legal challenges.

“We’re not just going to stay with what we’ve already done,” she said. “We’re going to look for other opportunities.”

McCarthy echoed these comments on the EPA Connect blog, writing “Heading into 2016, EPA is building on a monumental year for climate action—and we’re not slowing down in the year ahead.” In reviewing 2015, she highlighted announcement of the final Clean Power Plan—a regulation meant to reduce carbon dioxide emissions from power plants—and the global climate deal reached last month in Paris. She said her office will provide technical leadership to ensure consistent, transparent greenhouse gas reporting and inventory requirements under the global deal and would work to ensure the deal “is cast in stone.”

McCarthy is reportedly touring Ohio this week, touting President Obama’s energy and climate agenda (subscription).

Manmade Climate Change Evidence for Anthropocene Epoch

A group of geoscientists suggest that human activities, including those contributing to climate change, have altered the planet so much that their consequences are already detectable in the geological record and are reason to consider that sometime in the mid-twentieth century Earth moved into a new geologic epoch: the “Anthropocene.” As evidence that the planet has left the Holocene epoch, which began about 11,700 years ago, a new paper published in the journal Science points to mass extinction, reshaping of the planet’s surface, and anthropogenic deposits, including black carbon produced from fossil fuel combustion—all human impacts that the authors say should be acknowledged in the nomenclature.

The scale and rate of change in measures such as carbon dioxide and methane concentrations in the atmosphere, said Colin Waters, principal geologist at the British Geological Survey and one of the study authors, are larger and faster than the changes that defined the onset of the Holocene.

“What this paper does is to say the changes are as big as those that happened at the end of the last ice age,” Waters said. “That is a big deal.”

The case to approve the Anthropocene as a new epoch will be presented to the International Commission on Stratigraphy later this year.

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.

Study Says Electricity Production Vulnerable to Climate Change

The Nicholas Institute for Environmental Policy Solutions at Duke University
The Nicholas Institute for Environmental Policy Solutions at Duke University

A new study in the journal Nature Climate Change suggests that climate-change-related water disruptions could significantly decrease electricity production by the hydropower stations and thermoelectric (nuclear, fossil-fueled, biomass-fueled) plants that account for 98 percent of production around the world. Because the plants need water to cool generators and pump power at dams, they are vulnerable to lower river levels and warmer water temperatures, according to researchers at Wageningen University and the International Institute for Applied Systems Analysis (IIASA). These conditions could reduce generating capacity by as much as 74 percent in hydro plants and 86 percent in thermoelectric plants between 2040 and 2069.

“This is the first study of its kind to examine the linkages between climate change, water resources and electricity production on a global scale,” said co-author and IIASA Energy Program Director Keywan Riahi (subscription). “We clearly show that power plants are not only causing climate change, but they might also be affected in major ways by climate.”

The study, which used computer modeling and data from more than 24,000 hydropower plants and nearly 1,500 thermoelectric plants, indicates that the areas most at risk of decreases in usable capacity for electricity production are the United States, southern and central Europe, Southeast Asia, southern parts of South America, Africa and Australia—regions where the study authors say big increases in water temperature will combine with projected decreases in mean annual streamflow.

The potential water supply shortfall coincides with a predicted doubling in demand for water for power generation over the next 40 years.

The study also explored adaptation measures, concluding that increases in power plant efficiency and switches in cooling sources would reduce most regions’ vulnerability to water constraints as would improved cross-sectoral water management during drought periods.

Data Points to Hotter Years

Late last year, the World Meteorological Organisation pegged 2011–15 as the hottest five-year period on record. But data from the Met Office suggests 2016 will be warm, too—warmer than the office’s forecast for 2015.

“This forecast suggests that by the end of 2016 we will have seen three record, or near-record years in a row for global temperatures,” said Adam Scaife, head of long-range prediction at the Met Office.

El Nino and climate change were among the reasons cited for the increase—an estimated 1.29 and 1.73 degrees Fahrenheit higher than the average global temperature in the second half of the 20th century. The Met Office, Express reports, does not expect the record-breaking run to continue indefinitely, but it shows how factors like an El Nino are working together to push temperatures to unprecedented levels of warmth.

Climate Central categorized the changes as a “global warming spurt,” that may be amplified by a slower-moving cycle of the Pacific Ocean—the Pacific Decadal Oscillation—that is also being amplified by climate change and that is the subject of some recent studies.

“Last time we went from a negative to a positive was the mid-70s,” said Gerald Meehl, a National Atmospheric Research scientist, speaking about a warming slowdown linked to Pacific Decadal Oscillation. “Then we had larger rates of global warming from the 70s to the 90s, compared to the previous 30 years. It’s not just an upward sloping line. Sometimes it’s steeper, sometimes it’s slower.”

Clean Power Plan Sees Challengers, Supporters

The deadline for filing legal challenges to the U.S. Environmental Protection Agency’s (EPA) Clean Power Plan, which aims to limit carbon dioxide emissions from power plants, triggered a host of new lawsuits targeting the rule. To date, 27 states, along with trade groups and companies, are asking the U.S. Court of Appeals for the D.C. Circuit to delay implementation of the rule (subscription). Among the arguments—the EPA illegally issued duplicative rules for coal-fired plants and infringed on states’ rights (subscription).

Still, some states are beginning to wade through the rule. And many of the nation’s largest cities are seeking to back it. The National League of Cities, the U.S. Conference of Mayors and others are filing a motion to participate in litigation as amici curiae (friends of the court).

“The acute relevance of climate change to local governments’ responsibilities and activities has led members of the Local Government Coalition to grasp both the need to adapt to climate change and the costs of failing to act to mitigate it,” the filing said. “Prompted by lived experience and by the prospect of future impacts, they [the groups] have made efforts both to adapt to their changing climatic circumstances and to slow or eliminate their greenhouse gas emissions.”

 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.