A warming Arctic weakens the temperature difference between the tropics and the poles meaning less precipitation, weaker cyclones and weaker mid-latitude westerly wind flow — a recipe for prolonged drought.
Cody C. Routson, Nicholas P. McKay, Darrell S. Kaufman, Michael P. Erb, Hugues Goosse, Bryan N. Shuman, Jessica R. Rodysill, Toby Ault. Mid-latitude net precipitation decreased with Arctic warming during the Holocene. Nature, 2019; DOI: 10.1038/s41586-019-1060-3
When the Arctic warmed after the ice age 10,000 years ago, it created perfect conditions for drought. The temperature difference between the tropics and the poles drives a lot of weather. When those opposite temperatures are wider, the result is more precipitation, stronger cyclones and more robust wind flow. However, due to the Arctic ice melting and warming up the poles, those disparate temperatures are becoming closer.
“Our analysis shows that, when the Arctic is warmer, the jet stream and other wind patterns tend to be weaker,” says Bryan Shuman, a UW professor in the Department of Geology and Geophysics. “The temperature difference in the Arctic and the tropics is less steep. The change brings less precipitation to the mid-latitudes.”….
Sebestyen et al. Unprocessed atmospheric nitrate in waters of the Northern Forest Region in the USA and Canada. Environmental Science & Technology, 2019; DOI: 10.1021/acs.est.9b01276
Scientists have completed one of the largest and longest examinations to trace unprocessed nitrate movement in forests. The team found that some nitrate occasionally moves too fast for biological uptake, resulting in ‘unprocessed’ nitrate bypassing the otherwise effective filter of forest biology.
The study links pollutant emissions from various and sometimes distant sources including industry, energy production, the transportation sector and agriculture to forest health and stream water quality.
“Nitrogen is critical to the biological productivity of the planet, but it becomes an ecological and aquatic pollutant when too much is present,” said Stephen Sebestyen, a research hydrologist with the USDA Forest Service’s Northern Research Station based in Grand Rapids, Minn., and the study’s lead author….
“From public land managers to woodlot owners, there is a great deal of interest in forest health and water quality. Our research identifies widespread pollutant effects, which undermines efforts to manage nitrogen pollution.”
In the most extensive study to date on sea level rise in California, researchers say damage by the end of the century could be far more devastating than the worst earthquakes and wildfires in state history.
A team of U.S. Geological Survey scientists concluded that even a modest amount of sea level rise — often dismissed as a creeping, slow-moving disaster — could overwhelm communities when a storm hits at the same time. The study combines sea level rise and storms for the first time, as well as wave action, cliff erosion, beach loss and other coastal threats across California. These factors have been studied extensively but rarely together in the same model.
The results are sobering. More than half a million Californians and $150 billion in property are at risk of flooding along the coast by 2100 — equivalent to 6% of the state’s GDP, the study found, and on par with Hurricane Katrina and some of the world’s costliest disasters. The number of people exposed is three times greater than previous models that considered only sea level rise. ….Even a small shift in sea level rise could launch a new range of extremes that Californians would have to confront every single year.
“It’s not just some nuisance that’s going to pop its head up once in a while,” said Patrick Barnard, research director of the USGS Climate Impacts and Coastal Processes Team and lead author of the study. “These are significant events that are going to recur and be ten times the scale of the worst wildfires and earthquakes that we’ve experienced in modern California history.”….
….The latest National Climate Assessment, a major scientific report by 13 federal agencies, concluded $1 trillion in coastal real estate is threatened by rising sea levels, storm surges and high-tide flooding exacerbated by climate change….
Plastic garbage from Trader Joe’s and an AARP card are peeking out of hillocks of plastic trash piling up in Indonesia. It’s a sign of a new global quandary: What should wealthy countries do with their plastic waste now that China no longer is buying it?
For years, America sold millions of tons of used yogurt cups, juice containers, shampoo bottles and other kinds of plastic trash to China to be recycled into new products.And it wasn’t just the U.S. Some 70 percent of the world’s plastic waste went to China – about 7 million tons a year.
Numerous Chinese millionaires were minted as recycling businesses started and blossomed. Sure, they paid for the world’s plastic and paper trash, but they made far more money from processing it and selling the resulting raw materials.
But last year the Chinese government dropped a bombshell on the world recycling business: It cut back almost all imports of trash. And now a lot of that plastic gets shipped to other countries that don’t have the capacity to recycle it or dispose of it safely….
About ‘The Plastic Tide’
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Anasis et al. Optimal energy resource mix for the US and China to meet emissions pledges. Applied Energy, 2019; 238: 92 DOI: 10.1016/j.apenergy.2019.01.072
The United States could fulfill its greenhouse gas emission pledge under the Paris Climate Agreement by virtually eliminating coal as an energy source by 2024, according to new research.
….The researchers said eliminating coal as an energy source was the most significant step for the U.S. to meet its emissions target. As a result, the U.S. would need shift to an energy portfolio based on natural gas, efficiency, wind, solar power and biofuels, with oil used predominately for transportation fuel.
In the best of all worlds, nuclear power also would be part of the mix. The authors state that 12 new nuclear power plants would have to be built by 2025 to cost efficiently make up for the loss of coal, but that the goals could be reached without them at only a slightly higher cost….
Rogers et al. Wetland carbon storage controlled by millennial-scale variation in relative sea-level rise. Nature, 2019 DOI: 10.1038/s41586-019-0951-7
Some wetlands perform better under pressure. A new study revealed that when faced with sea-level rise, coastal wetlands respond by burying even more carbon in their soils. Coastal wetlands, which include marshes, mangroves and seagrasses, already store carbon more efficiently than any other natural ecosystem, including forests….
For wetlands that had faced rising seas, carbon concentrations doubled or nearly quadrupled in just the top 20 centimeters of soil. When the scientists looked deeper, at 50 to 100 centimeters beneath the surface, the difference hit five to nine times higher.
The extra boost comes because the carbon added to wetland soils by plant growth and sediment is buried faster as wetlands become wetter. Trapped underwater with little to no oxygen, the organic detritus does not decompose and release carbon dioxide as quickly. And the higher the waters rise, the more underwater storage space exists for the carbon to get buried.
….The trick, of course, is to ensure wetlands do not drown and disappear if waters rise too quickly. “Preservation of coastal wetlands is critical if they are to play a role in sequestering carbon and mitigating climate change,” Rogers said. For coastal wetlands to survive, they need space to migrate inland….
—In reality, green options are at best less harmful rather than restorative.The best thing for the environment would of course be for us to consume less overall. –We should give consumers immediate feedback on how much ‘eco-labeled’ and other products add to the environmental impact of what they are buying. For example, self-scanning systems in supermarkets could provide customers with an accumulated carbon footprint estimate of their shopping basket.
Sörqvist et al. Why People Harm the Environment Although They Try to Treat It Well: An Evolutionary-Cognitive Perspective on Climate Compensation. Frontiers in Psychology, 2019; 10 DOI: 10.3389/fpsyg.2019.00348
A new theory suggests that we think of our relationship with the environment like a social exchange, leading to the belief that ‘environmentally friendly’ behavior can compensate for ‘harmful’ behavior.
But unlike a social misstep, our environmental footprint cannot be smoothed over. Research reveals how advertisers, politicians and economic systems play on the psychology of ‘climate compensation’ — and encourages a more rational approach to environmental responsibility.
…”Reciprocity and balance in social relations have been fundamental to social cooperation, and thus to survival, so the human brain has become specialized through natural selection to compute and seek this balance,” says lead author Patrik Sörqvist, Professor of Environmental Psychology at the University of Gävle, Sweden. “But when applied to climate change, this social give-and-take thinking leads to the misconception that ‘green’ choices can compensate for unsustainable ones.”…. The best thing for the environment would of course be for us to consume less overall...
Fish provide a vital source of protein for over half the world’s population, with over 56 million people employed by or subsisting on fisheries. But climate change is beginning to disrupt the complex, interconnected systems that underpin this major source of food. …
These findings highlight the importance of accounting for the effects of climate change in fisheries management. This means coming up with new tools for assessing the size of fish populations, new strategies for setting catch limits that consider changing productivity, and new agreements for sharing catch between winning and losing regions….
Preventing overfishing will be a critical part of addressing the threat that climate change poses to the world’s fisheries….”It makes fish populations more vulnerable to warming, while warming hinders the recovery of overfished populations.”… Ocean acidification, falling oxygen levels and habitat loss will also impact marine life. More research is necessary to fully understand how climate change will affect fish populations and the livelihoods of people that depend on them.
Christopher M. Free, James T. Thorson, Malin L. Pinsky, Kiva L. Oken, John Wiedenmann, Olaf P. Jensen. Impacts of historical warming on marine fisheries production. Science, 2019 DOI: 10.1126/science.aau1758
Even efforts to use water more efficiently in municipal and industrial sectors won’t be enough to stave off shortages, say the authors of the new study. The results suggest that reductions in agricultural water use will probably play the biggest role in limiting future water shortages.
The new study is part of a larger 10-year U.S. Forest Service assessment of renewable resources including timber, rangeland forage, wildlife and water. …The new study finds climate change and population growth are likely to present serious challenges in some regions of the U.S., notably the central and southern Great Plains, the Southwest and central Rocky Mountain States, and California, and also some areas in the South and the Midwest.
The heart of the new analysis is a comparison of future water supply versus estimated water demand in different water-using sectors, like industry and agriculture….
Thomas C. Brown, Vinod Mahat, Jorge A. Ramirez. Adaptation to Future Water Shortages in the United States Caused by Population Growth and Climate Change. Earth’s Future, 2019; DOI: 10.1029/2018EF001091