The Nicholas Institute for Environmental Policy Solutions at Duke University

Democrats and Republicans are sharply divided on climate change in Congress but perhaps not so much at the municipal level. In a show of bipartisan support for the Paris Agreement and the Clean Power Plan at the conclusion of the U.S. Conference of Mayors in Miami Beach on Monday, leaders from more than 250 cities voted on symbolic resolutions calling for the Trump Administration to rejoin the global climate accord and embracing the goal of running their jurisdictions entirely on renewable energy by 2035. Another resolution called for President Trump and Congress to “develop a comprehensive risk management program to address future flood risks from sea level rise.”

“I think most mayors in America don’t think we have to wait for a president” whose beliefs on climate change are not supported by science, said New Orleans Mayor Mitch Landrieu. “There’s near unanimity in this conference that climate change is real and that humans contribute to it,” he said, adding “If the federal government refuses to act or is just paralyzed, the cities themselves, through their mayors, are going to create a new national policy by the accumulation of our individual efforts.”

The mayors showcased climate change with panels on climate resiliency and a neighborhood tour by Miami Mayor Philip Levine highlighting municipal efforts to cope with sea-level rise. Miami Beach is one of the U.S. cities most vulnerable to climate change.

Preliminary results of a survey jointly conducted by the U.S. Conference of Mayors (USCM) and the Center for Climate and Energy Solutions were released at the conference on Saturday. According to USCM, the survey of 66 municipalities, ranging from 21,000 to 8.5 million residents across 30 states, found “overwhelming interest by cities in collaborating with the private sector to accelerate climate efforts.”

On Tuesday at a Senate appropriations subcommittee hearing, U.S. Environmental Protection Agency (EPA) head Scott Pruitt suggested that the Clean Air Act may not have given his agency the tools for those efforts, telling committee members that the EPA’s endangerment finding, which established that greenhouse gas emissions were harmful to human health, did not settle the question of how the agency should regulate those emissions.

Massachusetts v. EPA simply said to the EPA that it had to make a decision on whether it had to regulate, whether it posed a risk to health, and there was an endangerment finding that followed that in 2009. It did not address whether the tools were in the toolbox,” Pruitt said. He added, “I think what’s important is that we are responding to the CO2 issue through the regulation of mobile sources, we’re also evaluating the steps or the tools we have in the toolbox with respect to stationary sources, and that’s our focus,” he said.

Challenging Pruitt’s assertion that the Clean Air Act gave the EPA no clear authority to regulate carbon emissions, John Walke, clean air director at the Natural Resources Defense Council, pointed to two Supreme Court cases—American Electric Power Co. v. Connecticut and Utility Air Regulatory Group v. EPA—affirming that authority, specifically with regard to emissions from stationary sources.

Global Sea-Level Rise Accelerates

A new study, published Monday in the journal Nature Climate Change, adds to recent literature confirming an acceleration in sea-level rise during the past few decades. That literature, which includes a study published in early June that found a tripling of the rate of sea-level increase between 1990 and 2012, is significant in part because of earlier uncertainty about whether global waters were indeed rising—uncertainty cited by climate change deniers. Specifically, the new study reveals the close match between what scientists know about contributors to sea-level rise and measured rates from satellites, and it nails down the sea-level rise acceleration.

The study led by Xianyao Chen of the Ocean University of China and Qingdao National Laboratory of Marine Science and Technology showed that the main contributor to recent sea-level rise is the thawing of Greenland’s ice sheet. The study found that the annual rate of sea-level rise had reached 0.13 inches in 2014. But ocean levels rose 50 percent faster in 2014 than in 1993, with meltwater from the Greenland ice sheet making up 25 percent of total sea level increase compared with 5 percent 20 years earlier. That finding suggests that the rate will continue to accelerate, and scientists say oceans are likely to rise about three feet by century’s end.

The study co-authors said the rate’s acceleration “highlights the importance and urgency of mitigating climate change and formulating coastal adaptation plans to mitigate the impacts of ongoing sea level rise.”

Climate Change-Related Fires Increase in the Arctic

Recent massive fire years in Alaska and Canada have been driven by extreme lightning storms that are likely to move north with climate warming, according to findings in Nature Climate Change by researchers from Vrije Universiteit Amsterdam and the University of California, Irvine. The scientists found that as fires creep northward, near the transition from boreal forests to Arctic tundra, large amounts of carbon currently locked in permafrost could be released. In addition, trees could begin growing in the tundra, darkening surfaces previously covered with snow, which prevents the reflection of sunlight away from Earth and contributes to global warming.

Using satellite and ground-based data, the researchers discovered that lightning-caused fires have risen 2 to 5 percent a year for the last four decades. The reason? Warmer temperatures increase thunderstorms, which in turn increase lightning and fire risk. These changes are part of a complex climate feedback loop, said Sander Veraverbeke of Vrije Universiteit Amsterdam, the study’s lead author.

“You have more fires; they creep farther north; they burn in these soils which have a lot of C02 and methane that can be exposed directly at the moment of the fire and then decades after,” Veraverbeke said. “That contributes again to global warming; you have again more fire.”

The study was prompted by immense fires in Alaska and Canada’s Northwest Territories in two of the last three years. Lightening was the cause of some 82 percent of the burned areas in the Northwest Territories in 2014 and 95 percent of the burned areas in Alaska in 2015—areas that don’t usually experience fires, according to Veraverbeke.

“These fires are claiming an area that they haven’t burned historically, which also means they can change the carbon balance and shift an ecosystem into a different state,” Veraverbeke said.

The Nicholas Institute for Environmental Policy Solutions at Duke University

The Nicholas Institute for Environmental Policy Solutions at Duke University

A study published last week in Nature Geoscience provides the first measurements of greenhouse gases from permafrost under Arctic lakes in Alaska, Siberia, and Canada. Although the research reveals that only a small amount of old carbon has been released in the past 60 years, it also suggests that much more could be released as the Arctic warms up faster than any other place on Earth.

“It’s a lit fuse, but the length of that fuse is very long,” said lead author Katey Walter Anthony of the University of Alaska. “According to the model projections, we’re getting ready for the part where it starts to explode. But it hasn’t happened yet.”

The scientists determined that the permafrost-carbon feedback is thus far small by looking at aerial photographs and using radiocarbon dating to determine the age of methane emitted from the Arctic lakes that are expanding to consume and thaw terrestrial permafrost. As that permafrost melts and decomposes, it releases ancient carbon as carbon dioxide and methane. Analysis of 113 radiocarbon dating measurements and 289 soil organic carbon measurements showed that approximately 0.2 to 2.5 petagrams of permafrost carbon was released as methane and carbon dioxide in the past six decades.

The billions of tons of carbon stored in permafrost are approximately double the amount currently in the atmosphere. Many researchers are concerned that emission of that stored carbon will contribute to warming that then contributes to permafrost thawing in an accelerating feedback loop.

NASA: Temperature Reconstructions Suggest Achievement of Paris Agreement Goals “Unlikely”

The Paris Agreement’s goal to limit Earth’s temperature increase to “well below” 2 degrees Celsius and to pursue efforts to limit that increase to 1.5 degrees Celsius above pre-industrial levels is unlikely to be achieved according to temperature reconstructions from the National Oceanic and Atmospheric Administration and the National Aeronautical and Space Administration (NASA). Those reconstructions reveal that the world is heating up faster than at any other time within the past 1,000 years. Over the next 100 years, according to NASA, it will continue to warm at least 20 times faster than the historical average.

“In the last 30 years we’ve really moved into exceptional territory,” said Gavin Schmidt, director of NASA’s Goddard Institute for Space Studies. “It’s unprecedented in 1,000 years. There’s no period that has the trend seen in the 20th century in terms of the inclination (of temperatures). Maintaining temperatures below the 1.5C guardrail requires significant and very rapid cuts in carbon dioxide emissions or coordinated geo-engineering. That is very unlikely. We are not even yet making emissions cuts commensurate with keeping warming below 2C.”

Using evidence left in tree rings, layers of ice in glaciers, ocean sediments, coral reefs, and layers of sedimentary rocks, NASA figures that the past century’s warming of 0.7 degrees Celsius is roughly 10 times faster than the average rate of ice-age-recovery warming.

This year, the average global temperature reached 1.38 Celsius above levels observed in the 19th century, just 0.12 Celsius below the 1.5 Celsius limit that nations aimed for in the Paris Agreement.

Climate Change Major Focus at G20 Summit

Climate change is among the topics world leaders are expected to discuss at a G20 summit in China, beginning September 4.

“This is the first time that the G20 leaders are gathering to discuss the Sustainable Development Goals and climate change, (and) how we implement them in parallel,” said United Nations Secretary-General Ban Ki Moon.

President Obama, who began his 10-day trip to Asia on Wednesday, is expected to stress the urgency of climate change. And some media outlets are reporting that the United States and China are expected to announce their ratification of the Paris Agreement prior to the start of the G20 Summit, but the White House has made no formal statement to this effect.

“We’ve made the commitment that we will join in 2016. And we’ve made the commitment to do that as soon as possible this year,” said Brian Deese, senior advisor to the president. “With respect to exactly when, I don’t have any announcements on that front. But we’ve committed, and we’ve been working on that issue.”

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.