April 30 2018

April 30 2018

ocean circulation, future rainfall, Pruitt’s actual success, moving carbon from air to soil

The Washington Post reports on research demonstrating that the Atlantic Meridional Overturning Circulation (AMOC), the current that carries warmth into the Northern Hemisphere’s high latitudes (the “Gulf Stream”), is slowing down because of climate change. The AMOC has declined in strength by 15 percent since the mid-20th century to a “new record low” according to a recent study published in Nature (RealClimate has an informative blog post by one of the paper’s authors about their findings and related recent research, and Nature has also published a less technical summary).

As some recall, a sharp decline in the AMOC was the “scientific” component of the plot of the movie The Day After Tomorrow (2004). While such wild and immediate impacts are not considered plausible there is no doubt that a weakening AMOC can produce major impacts to our climate, including scenarios for abrupt climate change. While some scientists debate the significance of the findings in terms of the timing of impacts, others are quite concerned that this measured slowing, which is a predicted outcome global warming, is occurring “a century ahead of schedule.” The paper’s authors consider the changes in AMOC to be linked to the remarkable warming that has occurred in the Gulf of Maine, which has altered the region’s famed fisheries.

A slowing of the AMOC will also result in accelerated sea level rise on the east coast of North America as the flowing water shifts back toward the continent. An excellent article in Yale Environment360 examines this and other factors that are contributing to higher than previously predicted sea level rise on the east coast (a study published last year shows that from 2011 to 2015, sea level rose up to 5 inches — an inch per year — in some parts of the southeast Atlantic coast).

The Guardian reports on a new project in Louisiana that will divert the waters of the Mississippi into wetlands to reverse the impacts of saltwater intrusion. Business Insider reports on the planned resettlement by the government of the residents of Isle de Jean Charles, Louisiana, and the remarkable complexities of moving an entire community (e.g., what about the cemetery?).

The New York Times reports that world’s shipping industry has defined its commitment to tackle climate change for the first time, bringing it closer in-line with the Paris Agreement. Shipping and aviation are two major greenhouse-gas-producing sectors that were not addressed under the Paris climate agreement. Both sectors are difficult to decarbonize since they rely on energy-dense fossil fuels to travel great distances without stopping.

The New Republic suggests that the idea that Scott Pruitt has been successful at rolling back environmental and health protections is more concept than reality. Inside Climate News reports that a new study suggests EPA has veered so far from its public health-based mission that it risks being captured by industry. Robert Redford writes in the Washington Post that Pruitt is doing plenty of damage.

Dave Roberts at Vox points out an important truth; while renewable sources are reducing the carbon footprint of our nation’s electricity, emissions from other sectors continue to climb. We are going to have to take much more aggressive action in the transportation, industrial, and building sectors if we are going to make the necessary progress toward decarbonizing our economy. The New York Times magazine has a great article about using compost in agriculture to enhance soil uptake of carbon from the atmosphere, which focuses on the work of the Marin Carbon Project. Another article reviews the possibility of enhancing natural mineralization processes to pull carbon from the atmosphere where the local geology is favorable, including in Oman.

As part of a current case in federal court brought by the cities of San Francisco and Oakland on behalf of the people of California against a group of major fossil fuel companies (People of the State of California v. BP P.L.C. et al.), Judge William Alsup asked for a climate science tutorial, which was provided in part by Dr. Myles Allen of the University of Oxford. This tutorial, which is an excellent presentation of the key findings from climate science over the last 200 years, is now online at RealClimate for those who are interested.

The Los Angeles Times reports on a recent study by UCLA scientists that projects California will experience a 100-200% increase in very wet years similar to the 2016-2017 rainy season by the end of the century. The authors suggest the frequency of serial storms on the scale of great flood of 1862 will increase 300-400%, with an increase as well in the frequency of droughts. This will challenge the capacity of our aging flood-control networks, enhance the threat of wildfires, and further complicate the management of California’s water system.

The Washington Post reports on a study of sea level rise in the tropical Pacific conducted for the Department of Defense. A key vulnerability the study identifies is the salinization of drinking water supplies (aquifers) caused by ocean waves over-washing low-lying atolls. The atoll of Roi-Namur in the Marshall Islands, which will not likely be inundated this century, will nevertheless face saltwater contamination of its aquifers with only 40 centimeters (about 15 inches) of sea-level rise. Roi-Namur is home to a large US defense installation manned by 1,250 American civilians, contractors, and military personnel.

Reuters reports on a recent study of the Regional Greenhouse Gas Initiative (RGGI) in New England, which concludes that “RGGI slashed greenhouse gas pollution, created thousands of jobs in clean energy, and cut consumer power costs.” And, as the US is setting national records for generating electricity from wind, it is politically important to note that it is “red states” that are leading the way.

Science News reports that scientists are running for Congress in unprecedented numbers. The Huffington Post quotes 314 Action founder Shaugnessy Naughton; “these are not people that envision themselves as politicians and build a résumé around that. These are people that are genuinely outraged and concerned by the direction the country is going in.”

Matthew Miller of the Nature Conservancy describes Nine Reasons to Feel Positive About the Planet.