Amazon forests: Biodiversity is a “must-have” to help mitigate climate risks

A forest with greater diversity of plants can better adjust to climatic stress under moderate climate change scenario

https://www.sciencedaily.com/releases/2016/08/160829122237.htm

August 29, 2016

“Plant trait diversity may enable the Amazon forests, the world’s greatest and maybe most fascinating tropical ecosystem, to adjust to some level of climate change — certain trees dominant today could decrease and their place will be taken by others which are better suited for the new climate conditions in the future,” says Boris Sakschewski from the Potsdam Institute for Climate Impact Research (PIK), lead-author of the study to be published in Nature Climate Change. Tree survival for instance depends on what the scientists call ‘leaf economics’: their different size, thickness, longevity or density defines how well the plant can deal with higher temperatures and water scarcity. “Biodiversity shows not to be a nice-to-have but indeed a must-have,” says Sakschewski. “We find it could be functional for the long-term survival of Earth’s large reservoirs of biomass, such as the forests of the Amazon region.”

However, this depends on the level of stress. Only in a scenario of moderate climate change, high biodiversity can, after a sharp decline of biomass, contribute to substantial recovery in vast areas across the Amazon region after a few hundred years. Here, more than 80 percent of the Amazon area would show substantial regrowth, according to the study. In contrast, in a business-as-usual scenario of greenhouse-gas emissions leading to massive climate change, less than 20 percent of the area would show this positive effect. Never before have these dynamics been integrated in a biogeochemical vegetation simulation of climate effects, so this is a significant step forward in Earth system modelling….

Boris Sakschewski, Werner von Bloh, Alice Boit, Lourens Poorter, Marielos Peña-Claros, Jens Heinke, Jasmin Joshi, Kirsten Thonicke. Resilience of Amazon forests emerges from plant trait diversity. Nature Climate Change, 2016; DOI: 10.1038/nclimate3109

The ‘Social Cost of Carbon’ – Historic Climate Change Decision $36 per ton (or $220 per ton?)

For the first time, the federal government has put a price on carbon dioxide and it’s bound to transform how we fight global warming.

Jay Michaelson 08.29.16 10:00 PM ET

One of the most significant court cases about climate change was decided earlier this month by a federal appeals court in Chicago. Given that it was steeped in the enervating context of refrigerator regulations, you may have missed it. But amid the stultifying discussions of compressors and insulation foam was a crucial advance in our nation’s belated attempts to forestall global climate catastrophe. It all comes down to a new phrase: the Social Cost of Carbon. Here’s why it’s important. By law, government agencies—in this case, the Department of Energy—are often required to show that the benefits of a proposed regulation exceed the costs. …

But what about climate change? … But how do you capture the “benefits” of preventing cataclysmic climate change? Beginning in 2010, a group of economists and scientists set about answering that question. They tried to calculate the likely future costs of shifting climate zones, agricultural disruptions, more extreme events like Superstorm Sandy, more outbreaks of disease, and the many other effects of climate change. The result is the Social Cost of Carbon (SCC), which, long story short, was calculated to be $36 per ton. That figure, while admittedly an approximation, is the best estimate that the government has put forward so far…. “Putting a price on pollution in general, and carbon in particular, is the best strategy for motivating change in behaviors that cause harm,” Esty told The Daily Beast. “It’s been hard to figure out the right price… but the judges in this case made clear that this was a serious and thoughtful exercise… It wasn’t an eyeball guess.”

Indeed, while most industry groups have opposed the idea of an SCC, Esty said that having the SCC ratified by a federal appeals court (review by the Supreme Court is possible, but unlikely) will help companies who have already made commitments to sustainability. “There are a number of companies, after last year’s Paris Agreements, who are beginning to think about how to prepare for a world—not yet in place in the U.S. but in place in Europe—where there is a price on carbon,” he said. “Many large companies are thinking about what internal price for carbon they should use. The Social Cost of Carbon can be a rallying point for them, for investment planning and decisions on energy projects… the [$36 per ton] price can be taken up by companies in their internal analyses.”

…some environmental scientists have argued that the $36 per ton price is far too conservative. For example, a study published last year by two Stanford University scientists arrived at a price of $220 per ton. One of them, Frances Moore, told The Daily Beast that “the current models used in the government’s SCC essentially assume that climate change will not affect economic growth,” she said. “They assume climate change will have effects in some specific sectors, but the effect is not big enough to substantially alter the trajectory of economic development.”…. “There are some econometric studies that … find the effects of climate change on economic growth in poor countries could be large. Our paper simply incorporates these statistical findings into the model.” Moreover, Moore told The Daily Beast, “because impacts to economic growth compound over time, even small impacts to the growth rate have very large implications for total climate damages. This is why our value of $220 per ton is so much larger than the U.S. government’s value.”

Esty replied, “getting started with some kind of price is much better than no price. As the science gets better, we’ll have more clarity about what the harms are, and the costs of harms will be more clear. But having some price is critical and that’s what this case really does.”

http://www.thedailybeast.com/articles/2016/08/30/the-social-cost-of-carbon-is-the-most-historic-climate-change-decision-yet.html

Plants retain more water with more CO2 in environment—implications for current drought and hydrology studies

http://phys.org/news/2016-08-climate-impact-drought-previously.html#jCp

August 29, 2016

As a multiyear drought grinds on in the Southwestern United States, many wonder about the impact of global climate change on more frequent and longer dry spells. As humans emit more carbon dioxide into the atmosphere, how will water supply for people, farms, and forests be affected? A new study from the University of California, Irvine and the University of Washington shows that water conserved by plants under high CO2 conditions compensates for much of the effect of warmer temperatures, retaining more water on land than predicted in commonly used drought assessments.

According to the study published this week in the Proceedings of the National Academy of Sciences, the implications of plants needing less water with more CO2 in the environment changes assumptions of climate change impacts on agriculture, water resources, wildfire risk, and plant growth.

The study compares current drought indices with ones that take into account changes in plant water use. Reduced precipitation will increase droughts across southern North America, southern Europe and northeastern South America. But the results show that in Central Africa and temperate Asia—including China, the Middle East, East Asia and most of Russia—water conservation by plants will largely counteract the parching due to climate change. “This study confirms that drought will intensify in many regions in the future,” said coauthor James Randerson, UCI professor of Earth system science. “It also shows that plant water needs will have an important influence on water availability, and this part of the equation has been neglected in many drought and hydrology studies.”…

Global climate models already account for these changes in plant growth. But many estimates of future drought use today’s standard indices, like the Palmer Drought Severity Index, which only consider atmospheric variables such as future temperature, humidity and precipitation. “New satellite observations and improvements in our understanding hydrological cycle have led to significant advances in our ability to model changes in soil moisture,” said Randerson. “Unfortunately, using proxy estimates of drought stress can give us misleading results because they ignore well-established principles from plant physiology.”

Is this good news for climate change? Although the drying may be less extreme than in some current estimates, droughts will certainly increase, researchers said, and other aspects of climate change could have severe effects on vegetation. “There’s a lot we don’t know, especially about hot droughts,” Swann said. The same drought at a higher temperature might have more severe impacts, she noted, or might make plants more stressed and susceptible to pests. “Even if droughts are not extremely more prevalent or frequent, they may be more deadly when they do happen,” she said.

Abigail L. S. Swann^a,^b,¹, Forrest M. Hoffman^c,^d, Charles D. Koven^e, and James T. Randerson^f
lant responses to increasing CO2 reduce estimates of climate impacts on drought severity, Proceedings of the National Academy of Sciences, www.pnas.org/cgi/doi/10.1073/pnas.1604581113

No-name storm dumped three times as much rain in Louisiana as Hurricane Katrina

Washington Post https://www.washingtonpost.com/news/capital-weather-gang/wp/2016/08/19/no-name-storm-dumped-three-times-as-much-rain-in-louisiana-as-hurricane-katrina/

By Jason Samenow August 19 2016

 

The  Louisiana flood has taken at least 13 lives and damaged 40,000 homes. This multibillion-dollar disaster is a devastating example of the damage water can do and proves that a hurricane is not required to leave behind a flooding catastrophe.

This unnamed storm produced three times as much rain in Louisiana as Hurricane Katrina. The multi-day rainfall totals, shown … are stunning — many in the 20-30 inch range….

More e-cars, solar needed to reach tough new CA climate standard- 40% below 1990 levels, from 441 mt GHG to 260 mt

• To reach 40% below 1990 levels, must go from 441 million metric tons greenhouse gas emissions in 2014 to ~260 million metric tons in emissions by 2030
• Current laws get CA to ~375 million metric tons of greenhouse gas emissions by 2030, ~only 1/3 of the way to the new 2030 goal

http://www.mercurynews.com/science/ci_30298296/more-electric-cars-more-solar-power-expected-state

By Paul Rogers, progers@bayareanewsgroup.com

Posted:   08/27/2016 02:36:47 PM PDT | Updated

California is already a world leader in developing environmental policies that address climate change. But under a landmark bill sent to Gov. Jerry Brown on Wednesday requiring far steeper reductions in greenhouse gas emissions than anything the state has ever attempted, the next 15 years will likely see big changes for California residents.

Among the possibilities, experts say: Rules requiring automakers to make hundreds of thousands of electric cars. Penalties for people who buy gasoline-powered vehicles. New tax credits and incentives for solar farms and wind power. Tighter building-efficiency standards on windows, heating and water systems in homes and businesses. Labels at the supermarket showing each product’s carbon footprint. Hydrogen-powered trucks. Landfills that are required to capture natural gas and use it to heat homes. A big push for batteries to store energy at homes. Even with all those changes, however, the new targets will be difficult to reach…..The measure, a key victory for Brown, builds on AB 32, a law signed in 2006 by former Gov. Arnold Schwarzenegger that required the state to cut emissions to 1990 levels by 2020.

California is on track to meet that goal, having already cut emissions 9.4 percent from their peak in 2004, but to cut them another 40 percent in a decade and a half will require a host of new rules and incentives from the California Air Resources Board and other state agencies in the coming years, along with some new laws from the Legislature.

Studies by scientists at Lawrence Berkeley National Lab lay the math out clearly. In 2014, the most recent year for which data is available, California emitted 441 million metric tons of greenhouse gases. The target for 2020 is 431, but emissions will have to fall to roughly 260 to meet the target in state Sen. Fran Pavley’s bill.

There are key existing laws already in place that will help… Brown signed a law last year requiring that the state’s utilities produce 50 percent of their electricity from solar, wind and other renewable sources by 2030. And in 2009, President Barack Obama required automakers to double gas mileage standards nationwide from an average of 27 miles per gallon to 54 by 2025…Yet even with the huge savings from those laws, California will still get to only about 375 million metric tons of greenhouse gas emissions by 2030 — or about a third of the way to the 2030 goal, according to Lawrence Berkeley lab estimates.

….”There are many ways to get there,” he said… California could increase the renewable energy requirement beyond 50 percent, he said. Or it could begin to reduce the carbon footprint of natural gas that is used commonly in homes and businesses by requiring “recycled” natural gas from landfills to be mixed in with it. Or it could pass building rules requiring most appliances that now run on natural gas to run on electricity. It could require companies to use hybrid vehicles for delivery trucks, electrify diesel trains and expand research and incentives for home battery storage, so people could power their homes with electricity from their vehicle batteries while their electric cars sit in the driveway…

… The state has cut greenhouse gas emissions nearly 10 percent since 2004. And during that time, the state’s annual economic output has grown from $1.5 trillion to $2.2 trillion…. Dan Kammen, director of the renewable energy lab at UC Berkeley, said the new rules will spur innovation and investment, as previous California environmental laws have done.

“Utilities will be like eBay, brokering electricity sales from people’s rooftop solar systems,” he said. “We’re going to see homes built that have no natural gas lines to them, and solar on the roof with battery storage. You are going to see buildings built with chemical batteries built into the foundation to store energy.” California’s 40 percent reduction target by 2030 is similar to goals set by the European Union — regulations that scientists say are necessary to limit warming to about 4 degrees Fahrenheit over the rest of this century.

Coal Executive Says His Industry Must Confront Climate Change

Richard Reavey says climate denial is eerily parallel to the tobacco industry’s old tactics, which hurt that business long-term

By Benjamin Hulac, ClimateWire on August 25, 2016 in Scientific American

It’s one thing when environmentalists say that fossil fuel companies’ positions on climate change are similar to Big Tobacco’s past deflections about the hazards of smoking. It’s another entirely when it’s done by a coal official, who says his industry should heed tobacco’s costly lessons.

That’s what Richard Reavey, vice president of public affairs of Cloud Peak Energy Inc., a major coal miner in the western United States, appears to have done on June 29, 2015, when he presented a 24-page slideshow at an industry conference organized by the Rocky Mountain Coal Mining Institute in Snowmass, Colo. Reavey said one of his goals for the presentation, titled “SURVIVAL IS VICTORY: LESSONS FROM THE TOBACCO WARS,” was to encourage the industry to move past debating climate change and talk to critics of the industry about addressing greenhouse gas emissions and energy use.

“The tobacco industry spent a lot of time in the bunker not listening to its critics, denying that there was any legitimate concern about smoking and health, and effectively trying to parse hairs and debate science,” Reavey said in an interview, “instead of trying to get to where they finally got to, which was that recognition that regulation was a legitimate goal of the public health community and something that the industry could live with.” Coal companies should take a proactive strategy and talk about solutions, such as carbon capture utilization and storage (CCUS) technology, Reavey said….

http://www.scientificamerican.com/article/coal-executive-says-his-industry-must-confront-climate-change/

Study Finds Biofuels Worse for Climate than Gasoline

August 25th, 2016 By John Upton climatecentral.org

http://www.climatecentral.org/news/study-biofuels-worse-for-climate-than-gasoline-20634

Years of number crunching that had seemed to corroborate the climate benefits of American biofuels were starkly challenged in a science journal [Climatic Change] on Thursday, with a team of scientists using a new approach to conclude that the climate would be better off without them. Based largely on comparisons of tailpipe pollution and crop growth linked to biofuels, University of Michigan Energy Institute scientists estimated that powering an American vehicle with ethanol made from corn would have caused more carbon pollution than using gasoline during the eight years studied.

Most gasoline sold in the U.S. contains some ethanol, and the findings, published in Climatic Change, were controversial. They rejected years of work by other scientists who have relied on a more traditional approach to judging climate impacts from bioenergy — an approach called life-cycle analysis.

Following the hottest month on record globally, and with temperatures nearly 2°F warmer and tides more half a foot higher than they were in the 1800s, the implications of biofuels causing more harm to the climate than good would be sweeping.

The research was financially supported by the American Petroleum Institute, which represents fossil fuel industry companies and has sued the federal government over its biofuel rules. “I’m bluntly telling the life-cycle analysis community, ‘Your method is inappropriate,'” said professor John DeCicco, who led the work. “I evaluated to what extent have we increased the rate at which the carbon dioxide is being removed from the atmosphere?”

Lifecycle analyses assume that all carbon pollution from biofuels is eventually absorbed by growing crops. DeCicco’s analysis found that energy crops were responsible for additional plant growth that absorbed just 37 percent of biofuel pollution from 2005 to 2013, leaving most of it in the atmosphere, where it traps heat.

…The findings were criticized by scientists whose work is directly challenged by them…..Thursday’s paper provided fresh fuel for a heated debate among opposing groups of scientists over bioenergy’s climate impacts. Some are certain it’s a helper in the fight against climate change. Others are convinced it’s a threat.

DeCicco, J.M., Liu, D.Y., Heo, J. et al. Carbon balance effects of U.S. biofuel production and use. Climatic Change (2016). doi:10.1007/s10584-016-1764-4

Biological invasions threaten developing countries and remaining biodiversity strongholds

August 23, 2016 University of Exeter

Invasions from alien species such as Japanese Knotweed and grey squirrels threaten the economies and livelihoods of residents of some of the world’s poorest nations, new University of Exeter research shows.

The damage caused by non-native species like the Harlequin ladybird and mink threaten global biodiversity and cost global economies US$1.4 trillion annually. They can transmit disease, choke river systems and wells, prevent cattle being able to graze and out-compete or eat native species.

This is often seen as a “first world” problem. Experts have now shown these invasions are also threatening the last remaining biodiversity strongholds in the world’s most fragile economies. One sixth of the global land surface is highly vulnerable to invasion, including substantial areas in developing nations and areas with diverse species of birds and plants. A new study says better action is needed to protect people and the environment in areas with high levels of poverty.

Increasing globalization, especially imports of pets and plants, has have caused much of the biological invasions in the past. In the future air travel will be responsible for biological invasions of Africa and Asia. This will be exacerbated by climate change, and intensifying agriculture, which make it easier for invasive species to become established.

Rich nations are accustomed to the nuisance of invasive alien species, and are increasingly taking protective action. The study outlines how poorer economies are crucially reliant on international trade and have little power to regulate imports, so the introduction of highly dangerous species continues unchecked….”We’re rapidly shifting the ground under native species,” he said. “While species can presumably evolve to be better adapted to new conditions, we don’t know how long that could take.”

1. Regan Early, Bethany A. Bradley, Jeffrey S. Dukes, Joshua J. Lawler, Julian D. Olden, Dana M. Blumenthal, Patrick Gonzalez, Edwin D. Grosholz, Ines Ibañez, Luke P. Miller, Cascade J. B. Sorte, Andrew J. Tatem. Global threats from invasive alien species in the twenty-first century and national response capacities. Nature Communications, 2016; 7: 12485 DOI: 10.1038/NCOMMS12485
   

https://www.sciencedaily.com/releases/2016/08/160823083217.htm

Forest and watercourse interplay important for restorations

August 24, 2016 Umea University

Humans utilise forests and watercourses in a way that depletes ecosystem habitats, biodiversity and ecosystem services. Many areas are restored to break the trend, but to succeed you need to consider not only the ecosystem in mind, but also surrounding ecosystems.
….”Despite evident correlations between land and water ecosystems, forests and watercourses are nearly always restored separately in small-scale projects. When a forest ecosystem abounding in water has been depleted, it

can be a struggle to retain its original status by restoring only one part of it. Instead, both land and aquatic environments need to be integrated in the restoration,” says Christer Nilsson, Professor at the Department of Ecology and Environmental Sciences at Umeå University.

Riparian zones along forest rivers are environments where forests and water meet and benefit from each other. The line of trees along the riparian zones provides shade and wood. Leaves and insects falling into the water are favourable for aquatic insects and bugs and eventually also for fish. Floodings wash up sediment, seeds and other plant parts onto riparian forest zones. New plants grow, which increases production and diversity. Aquatic larvae make up a good food source for insects, spiders, crustaceans, lizards and birds on land. Decaying fish carcasses removed from the river by large animals encourage the growth of riparian trees by enriching riparian areas with nitrogen. That in turn helps trees to grow and to shed more branches and leaves into the water….Free-flowing rivers surrounded by natural forest are expected to be more resistant to climate change than streams surrounded by clearcuts or urbanised areas.

Another problem is that most studies are conducted at a local level with focus on short-term effects. Long-term recovery is often unknown and in the few cases where restorations of watercourses and forests have been coordinated, they have rarely been evaluated. Both well thought-out, basic measurements and reference areas are needed for comparisons. Good knowledge on ecosystems and their functions in the landscape are necessary to evaluate and improve the measures taken in a restoration project.

“There are complex correlations over large areas to take into account, which means that seeing the final results of small-scale projects take time. Large-scale restoration projects with a landscape perspective stand a much higher chance of succeeding. Researchers and practicians who undertake restorations are faced with immense challenges ahead,” says Christer Nilsson.

https://www.sciencedaily.com/releases/2016/08/160824110856.htm

Joakim Hjältén, Christer Nilsson, Dolly Jørgensen, David Bell. Forest–Stream Links, Anthropogenic Stressors, and Climate Change: Implications for Restoration Planning. BioScience, 2016; 66 (8): 646 DOI: 10.1093/biosci/biw072

New map shows alarming growth of human footprint- 75% of Earth’s land surface altered

August 24, 2016 James Cook University

… a new map of the ecological footprint of humankind shows 97 per cent of the most species-rich places on Earth have been seriously altered….”The most species-rich parts of the planet — especially including the tropical rainforests — have been hit hardest. In total, around 97 per cent of Earth’s biologically richest real estate has been seriously altered by humans,” he said. The scientists found environmental pressures are widespread, with only a few very remote areas escaping damage.

“Humans are the most voracious consumers planet Earth has ever seen. With our land-use, hunting and other exploitative activities, we are now directly impacting three-quarters of the Earth’s land surface,” said Professor Laurance… Professor Laurance said the suitability of lands for agriculture appears to be a major determinant in where ecological pressures appeared around the globe.

“The bottom line is that we need to slow rampant population growth, especially in Africa and parts of Asia, and demand that people in wealthy nations consume less,” he said.

The updated and temporally intercomparable global terrestrial human footprint maps and the data behind have been published in Nature Communications and Nature Scientific Data.

https://www.sciencedaily.com/releases/2016/08/160824212227.htm

1. Oscar Venter, Eric W. Sanderson, Ainhoa Magrach, James R. Allan, Jutta Beher, Kendall R. Jones, Hugh P. Possingham, William F. Laurance, Peter Wood, Balázs M. Fekete, Marc A. Levy, James E. M. Watson. Sixteen years of change in the global terrestrial human footprint and implications for biodiversity conservation. Nature Communications, 2016; 7: 12558 DOI: 10.1038/ncomms12558