March 15 2024

March 15 2024

evidence that a major climate tipping point approaches, new nuclear plants generate electricity and higher costs, high ocean temperatures astonish scientists, gubernatorial candidate in North Carolina denies climate science, first large U.S. offshore-wind farm completed

The Guardian reports on a recent study suggesting that the Atlantic Meridional Overturning Circulation (AMOC), which includes the Gulf Stream and other powerful currents, “is already on track towards an abrupt shift, which has not happened for more than 10,000 years and would have dire implications for large parts of the world.” The AMOC is a key mechanism that distributes energy around the planet, and moderates the impact of global warming. A fundamental physical driver of the AMOC is the relative salinity of different ocean waters, but this is being disrupted by the extreme melting of ice in Greenland and the Arctic. A major shift in the AMOC would have vast global impacts, including more sea level rise in the Atlantic, flipping the wet and dry seasons in the Amazon, a colder and drier Europe and more erratic temperatures worldwide. The paper’s lead author, René van Westen, of Utrecht University, noted that we don’t know when these changes will occur, but they will be irreversible on human timescales. “We are moving towards it. That is kind of scary,” van Westen said. “We need to take climate change much more seriously.”

Inside Climate News has an excellent visualization of the AMOC, and one scientist notes that a large shift in the AMOC “is a going-out-of-business scenario for European agriculture.” The New York Times notes that this shift in the AMOC is one of many “tipping points” that the Earth’s climate system can reach, after which the climate continues to change irrespective of greenhouse-gas emissions from human activities. (I explored this issue, and how we can respond, in a 2021 blog post CODE RED: Time to Tip the Climate Odds in Our Favor).

For the more technically inclined, RealClimate also analyzes the recent study. While it used a model requiring enormous computing power to simulate ocean circulation (it took 6 months to run on 1,024 cores at the Dutch national supercomputing facility), it is based on key observations in the southern ocean that suggest the AMOC is slowing. RealClimate notes that the study (1) confirms the AMOC has a tipping point beyond which it breaks down, (2) the AMOC is on course toward tipping, although how fast is unknown, and (3) confirms past concerns that climate models systematically overestimate the stability of the AMOC. The analysis concludes that we “continue to ignore this risk at our peril.” This appears to be another situation in which we consider the unprecedented to be improbable, and we need to stop doing this.

Meanwhile, despite the threat of accelerated sea level rise on the Atlantic coast as the AMOC slows down, The New York Times notes that groundwater pumping is causing the land in this region to subside. This highlights the concept of relative sea level rise, where to understand a region’s vulnerability to rising oceans one needs to account for land movements as well. In Hampton Roads, Virginia, an area that is subsiding relatively quickly, local governments are pumping treated wastewater underground to try and slow the sinking. This trend is exacerbated by historic development of marshlands and other areas with soft soils that are compacting over time. The Washington Post reports that marsh subsidence, combined with sea level rise, is destroying Louisiana’s wetlands at a rate much faster than previously expected. This will increase the vulnerability of New Orleans, and other settled regions in Louisiana, to the impacts of sea level rise in future decades.

The New York Times describes the remarkable high temperatures being recorded in the world’s oceans, particularly the north Atlantic. 2023 had the highest global average sea surface temperatures ever recorded, and 2024 is starting out even higher. These temperatures will have major impacts, including adding more energy for the coming hurricane season. One scientist says, “It’s just astonishing. Like, it doesn’t seem real.” February 2024 was the hottest February ever for global air temperatures, and the ninth consecutive record month.

The AP reports that the second of two new nuclear reactors at the Vogtle plant in Georgia has reached a sustained nuclear-fission reaction, one of its key final milestones before commercial operation. The first of the new reactors, which are the only ones built in the U.S. in decades, is already operating. The reactors are seven years behind schedule, and their original estimated cost of $14 billion has ballooned to $35 billion. The New York Times describes a similar problem facing the Hinkley Point C nuclear-power station in Britain, where the 2016 price tag of £18 billion has now grown to £48 billion with more cost overruns likely before completion.

Inside Climate News checks in on the status of Lake Powell, the reservoir behind the Glen Canyon Dam, which had reached extremely low levels in 2022 after a megadrought that has entered its 22nd year. While the wet winter of 2023 helped bring the reservoir to higher levels, protecting the dam’s capacity to generate electricity for at least another few years, it is unlikely the reservoir will return to previous high levels given the increased aridity in the Colorado River basin due to climate change. Inside Climate News also describes how there are proposals in the American Southwest for mining minerals important to renewable-energy technologies, but the rising aridity may make these projects infeasible.

A well-established challenge facing the expansion of renewable energy is the need for more transmission (reviewed recently by Inside Climate News). The National Renewable Energy Laboratory has estimated that the U.S. needs to be adding 10,000 miles of transmission lines annually, but in 2022 we added only 670 miles, in part due to opposition by local landowners. The New Yorker visits northwestern Missouri, part of the proposed path of the Grain Belt Express transmission line, to understand the nature of local opposition.

Anthropocene Magazine describes a new possibility, reconductoring, in which existing transmission lines are replaced with lines that have a carbon-fiber core instead of a steel core. This allows more conductive aluminum to be used, enhancing the capacity of the existing lines and reducing transmission losses. The old aluminum can even be recycled to be used in the new lines. National reconductoring projects are already underway in Belgium and the Netherlands.

Electrek reports on a breakthrough from MIT regarding perovskite solar cells. These cells, which have demonstrated higher efficiencies than silicon cells, have been plagued by the tendency to degrade much more quickly. The MIT researchers have released a guidebook that describes how to treat perovskite cells in order to increase their productive life. This is being heralded as an important breakthrough, as perovskite cells can be used in a variety of applications that silicon cannot. The New York Times describes efforts to minimize the impact of solar farms on wildlife.

An op-ed in The New York Times describes the challenges that have stymied the cultured-meat industry. Just a few years ago, newspapers were full of visionary statements that cultured meat would make the livestock industry (and its enormous carbon footprint) obsolete in a matter of years. The reality appears to be that venture capital was used to build expensive facilities and push for government approval “before [the companies] had overcome the most fundamental technological challenges.”

Inside Climate News reports on the race for governor in North Carolina, where climate-change denial is alive and well. The Republican candidate, currently the state’s Lieutenant Governor, has called anthropogenic climate change a hoax that is based on “pseudoscience, junk science, that has not proven a single solitary thing.” Obviously, the world’s scientific community (and this humble reporter) clearly disagree. While the candidate’s denial of the holocaust and his desire to end women’s right to vote (reported by The New York Times) are topics for a different blog, these positions further demonstrate a complete disregard for facts that do not align with his opinions, which is a great threat to American democracy and to a stable climate.

Electrek reports that turbine construction is complete at the South Fork wind farm, which is already providing power to Long Island. This is the first utility-scale, offshore-wind project to be completed in the U.S. The AP notes that recently “the federal government has finalized two areas for floating offshore wind farms along the Oregon coast.” The ocean is deeper along the Pacific coast, requiring that turbines float rather than being mounted to the ocean floor, as is the case along the Atlantic coast.