Ocean Acidification Will Make Climate Change Worse

Given that they cover 70% of the Earth’s surface—and provide about 90% of the planet’s habitable space by volume—the oceans tend to get short shrift when it comes to climate change. The leaked draft of the forthcoming coming new report from the Intergovernmental Panel on Climate Change highlighted the atmospheric warming we’re likely to see, the rate of ice loss in the Arctic and the unprecedented (at least within the last 22,000 years) rate of increase of concentrations of greenhouse gases like carbon dioxide and methane. But when it came to the oceans, press reports only focused on how warming would cause sea levels to rise, severely inconveniencing those of us who live on land.

Some of that ignorance is due to the out of sight, out of mind nature of the underwater world—a place human beings have only seen about 5% of. But it has more to do with the relative paucity of data on how climate change might impact the ocean. It’s not that scientists don’t think it matters—the reaction of the oceans to increased levels of CO2 will have an enormous effect on how global warming impacts the rest of us—it’s that there’s still a fair amount of uncertainty around the subject.

But here’s one thing they do know: oceans are absorbing a large portion of the CO2 emitted into the atmosphere—in fact, oceans are the largest single carbon sink in the world, dwarfing the absorbing abilities of the Amazon rainforest. But the more CO2 the oceans absorb, the more acidic they become on a relative scale, because some of the carbon reacts within the water to form carbonic acid. This is a slow-moving process—it’s not as if the oceans are suddenly going to become made of hydrochloric acid. But as two new studies published yesterday in the journal Nature Climate Change shows, acidification will make the oceans much less hospitable to many forms of marine life—and acidification may actually to serve to amplify overall warming.

The first study, by the German researchers Astrid Wittmann and Hans-O. Portner, is a meta-analysis looking at the specific effects rising acid levels are likely to have on specific categories of ocean life: corals, echinoderms, molluscs, crustaceans and fishes. Every category is projected to respond poorly to acidification, which isn’t that surprising—pH, which describes the relative acidity of a material, is about as basic a function of the underlying chemistry of life as you can get. (Lower pH indicates more acidity.) Rapid changes—and the ocean is acidifying rapidly, at least on a geological time scale—will be difficult for many species to adapt to.

Corals are likely to have the toughest time. The invertebrate species secretes calcium carbonate to make the rocky coastal reefs that form the basis of the most productive—and beautiful—ecosystems in the oceans. More acidic oceans will interfere with the ability of corals to form those reefs. Some coral have already shown the ability to adapt to lower pH levels, but combined with direct ocean warming—which can lead to coral bleaching, killing off whole reefs—many scientists believe that corals could become virtually extinct by the end of the century if we don’t reduce carbon emissions.

The Nature Climate Change study found that mollusks like oysters and squids will also struggle to adapt to acidification, though crustaceans like lobsters and crabs—which build lighter exoskeletons—seem likely to fare better. With fish it’s harder to know, though those species that live among coral reefs could be in trouble should the coral disappear. But ultimately, as the authors point out, “all considered groups are impacted negatively, albeit differently, even by moderate ocean acidification.” No one gets out untouched.

The other Nature Climate Change study—by American, German and British researchers—looked at the effects that ocean acidification could have on atmospheric warming. It turns out there may be some feedback—the researchers found that as the pH of the oceans dropped, it would result in lower concentrations of the biogenic sulfur compound dimethylsulphide (DMS). Why does that matter? Marine emissions of DMS are the largest natural source of atmospheric sulfur. (Manmade sources of sulfur include the burning of coal.)

Sulfur, in the form of sulfur dioxide, isn’t a greenhouse gas. But higher levels of sulfur in the atmosphere can reduce the amount of solar energy reaching the Earth’s surface, causing a cooling effect. (In the aftermath of the eruption of Mt. Pinatubo in the Philippines in 1991, which threw millions of tons of sulfur dioxide into the atmosphere, average global temperatures the two years fell by about 0.5 C.) If acidification decreases marine emissions of sulfur, it could cause an increase in the amount of solar energy reaching the Earth’s surface, speeding up warming—which is exactly what the Nature Climate Change study predicts. It’s one more surprise that the oceans have in store for us.

Source:: http://science.time.com

Top Predators Key to Extinctions as Planet Warms

Global warming may cause more extinctions than predicted if scientists fail to account for interactions among species in their models, Yale and UConn researchers argue in Science.

"Currently, most models predicting the effects of climate change treat species separately and focus only on climatic and environmental drivers," said Phoebe Zarnetske, the study's primary author and a postdoctoral fellow at the Yale School of Forestry & Environmental Studies. "But we know that species don't exist in a vacuum. They interact with each other in ways that deeply affect their viability."

Zarnetske said the complexity of "species interaction networks" discourages their inclusion in models predicting the effects of climate change. Using the single-species, or "climate envelope," approach, researchers have predicted that 15 percent to 37 percent of species will be faced with extinction by 2050.
But research has shown that top consumers -- predators and herbivores -- have an especially strong effect on many other species. In a warming world, these species are "biotic multipliers," increasing the extinction risk and altering the ranges of many other species in the food web.

"Climate change is likely to have strong effects on top consumers. As a result, these effects can ripple through an entire food web, multiplying extinction risks along the way," said Dave Skelly, a co-author of the study and professor of ecology at Yale.

The paper argues that focusing on these biotic multipliers and their interactions with other species is a promising way to improve predictions of the effects of climate change, and recent studies support this idea. On Isle Royale, an island in Lake Superior, rising winter temperatures and a disease outbreak caused wolf populations to decline and the number of moose to surge, leading to a decline in balsam fir trees. Studies in the rocky intertidal of the North American Pacific Coast show that higher temperatures altered the ranges of mussel species and their interaction with sea stars, their top predators, resulting in lower species diversity. And in Arctic Greenland, studies show that without caribou and muskoxen as top herbivores, higher temperatures can lead to decreased diversity in tundra plants and, in turn, affect many other species dependent on them.

"Species interactions are necessary for life on Earth. We rely on fisheries, timber, agriculture, medicine and a variety of other ecosystem services that result from intact species interactions," said Zarnetske. "Humans have already altered these important species interactions, and climate change is predicted to alter them further. Incorporating these interactions into models is crucial to informed management decisions that protect biodiversity and the services it provides."

Multispecies models with species interactions, according to the paper, would enable tracking of the biotic multipliers by following how changes in the abundance of target species, such as top consumers, alter the composition of communities of species. But there needs to be more data.

"Collecting this type of high-resolution biodiversity data will not be easy. However, insights from such data could provide us with the ability to predict and thus avoid some of the negative effects of climate change on biodiversity," said Mark Urban, a co-author and an assistant professor in the Department of Ecology and Evolutionary Biology at the University of Connecticut.

Source: http://www.sciencedaily.com

The Cost of Climate Change Is Jobs

The weather in South Africa is beautiful -- warm during the day, cool and breezy at night. This is a unique and fitting place to stage the United Nations Climate Change Conference, as South Africa prepares for the impacts of climate change.


The costs of adapting to climate change are not limited to South Africa or other countries that the UNFCCC framework considers "developing." The cost is something that we in the United States deal with on a daily basis, even if there are still powerful "climate deniers" in Congress who aren't willing to admit it. From the costs of increasingly severe weather events to the rising cost of food from climate-related droughts, Americans pay for global warming every day.

But the biggest cost that we pay is in lost opportunity. As it stands, the U.S. is failing to take advantage of the opportunities to create good jobs by addressing climate change. This makes less and less sense as our economy struggles to regain its footing, and as millions of Americans continue to search for work.

The BlueGreen Alliance is in Durban this week advocating for a framework to address climate change that spurs economic growth and job creation in the United States. The 15 partners of the BlueGreen Alliance -- 11 of America's largest labor unions and four of its most influential environmental organizations -- released a statement this week, "Fighting Climate Change, Creating Jobs," which advocates international climate action grounded in science-based greenhouse gas reduction targets, urging the U.S. to pursue emissions reductions as aggressively as possible by taking all feasible steps to meet current near term targets. This can be achieved through investments and policies that will build a strong clean energy economy, create new jobs for American workers and improve U.S. competitiveness in the global economy.

We can accomplish these goals through smart policies and strategic investments in building a truly 21st century American economy. Growing the production of clean energy in the United States while making our transportation systems, industries, building stock, transmission and communications systems more efficient will both create jobs and ensure that America is competitive in an increasingly efficient global economy.

On Friday, the Labor Department announced that the American economy had gained about 120,000 jobs in November. A positive number is a good number. But we have to face facts: we aren't going to put eight million people back to work with a piecemeal approach to our economy. It's no longer acceptable to sit on the sidelines and hope that jobs will be created and that our economy will recover by returning to an unsustainable pre-2008 economic model. It's no longer an option to deny the impact of climate change on our economy. We need action to build the industries that will drive our future economy in the United States, and we need it now.

In Durban this week, thousands of people from around the world are gathering to advocate for an agreement that will avert the worst impacts of climate change and help impacted nations adapt. Whether in South Africa or in the United States, the cost of climate change is deep and far reaching. It's costing us money. It's costing us economic growth. And it's costing us jobs.

Source: www.huffingtonpost.com

Geoengineering: Scientists Debate Risks Of Sun-Blocking And Other Climate Tweaks To Fight Warming

To the quiet green solitude of an English country estate they retreated, to think the unthinkable.


Scientists of earth, sea and sky, scholars of law, politics and philosophy: In three intense days cloistered behind Chicheley Hall's old brick walls, four dozen thinkers pondered the planet's fate as it grows warmer, weighed the idea of reflecting the sun to cool the atmosphere and debated the question of who would make the decision to interfere with nature to try to save the planet.

The unknown risks of "geoengineering" – in this case, tweaking Earth's climate by dimming the skies – left many uneasy.

"If we could experiment with the atmosphere and literally play God, it's very tempting to a scientist," said Kenyan earth scientist Richard Odingo. "But I worry."

Arrayed against that worry is the worry that global warming – in 20 years? 50 years? – may abruptly upend the world we know, by melting much of Greenland into the sea, by shifting India's life-giving monsoon, by killing off marine life.

If climate engineering research isn't done now, climatologists say, the world will face grim choices in an emergency. "If we don't understand the implications and we reach a crisis point and deploy geoengineering with only a modicum of information, we really will be playing Russian roulette," said Steven Hamburg, a U.S. Environmental Defense Fund scientist.

The question's urgency has grown as nations have failed, in years of talks, to agree on a binding long-term deal to rein in their carbon dioxide and other greenhouse-gas emissions blamed for global warming. The Intergovernmental Panel on Climate Change (IPCC), the U.N.-sponsored science network, foresees temperatures rising as much as 6.4 degrees Celsius (11.5 degrees Fahrenheit) by 2100, swelling the seas and disrupting the climate patterns that nurtured human civilization.

Science committees of the British Parliament and the U.S. Congress urged their governments last year to look at immediately undertaking climate engineering research – to have a "Plan B" ready, as the British panel put it, in case the diplomatic logjam persists.

Britain's national science academy, the Royal Society, subsequently organized the Chicheley Hall conference with Hamburg's EDF and the association of developing-world science academies. From six continents, they invited a blue-ribbon cross-section of atmospheric physicists, oceanographers, geochemists, environmentalists, international lawyers, psychologists, policy experts and others, to discuss how the world should oversee such unprecedented – and unsettling – research.

Read the full story at:

http://www.huffingtonpost.com/2011/04/04/geoengineering-sun-blocking_n_844324.html