Tag: ocean

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Coral Bleaching Linked to Climate Change, Other Factors

The Nicholas Institute for Environmental Policy Solutions at Duke University
The Nicholas Institute for Environmental Policy Solutions at Duke University

The Great Barrier Reef, which last year narrowly avoided being put on the World Heritage endangered list, is experiencing its worst bleaching in recorded history. According to the Great Barrier Reef Marine Park Authority, overall mortality of the reef is 22 percent, but along Lizard Island, off far north Queensland, it’s 93 percent. Coral bleaching is also occurring along the Maldives, Thailand, and Christmas Island.

By year’s end, what the National Oceanic and Atmospheric Administration (NOAA) has designated the third global coral bleaching in less than two decades, and the longest and most severe so far, will have killed 12,000 square kilometers of reefs and affected more than a third of the world’s corals.

Satellite data produced for The Guardian by Mark Eakin, head of NOAA’s Coral Reef Watch, reveals the increasingly widespread impact of ocean temperature increases on the Great Barrier Reef, where bleaching is predicted to become an annual event by 2020.

“While there was a considerable amount of variability—from El Niños and other things—there was an obvious upward trend in the data,” Eakin said. “So you’re looking at the background warming, which is having a major effect on the corals.”

Although coral bleaching is thought to result largely from abnormally high sea temperatures that kill marine algae crucial for coral health, a study published Tuesday in Nature Communications and based on a three-year experiment on a coral reef in the Florida Keys nuances that understanding. Its authors say that widespread coral deaths observed in recent decades are being caused by a combination of multiple local stressors that become lethal in the presence of higher temperatures.

“This makes it clear there’s no single force that’s causing such widespread coral deaths,” said study co-author Rebecca Vega Thurber of Oregon State University. “Loss of fish that help remove algae, or the addition of excess nutrients like those in fertilizers, can cause algal growth on reefs. This changes the normal microbiota of corals to become more pathogenic, and all of these problems reach critical levels as ocean temperatures warm.”

United States and India Announce Climate and Energy Agreements

On Tuesday, following a meeting with President Obama partly focused on climate change and energy, Indian Prime Minister Narendra Modi said his country, the world’s third-largest greenhouse gases producer, would ratify the Paris Agreement this year. The action is considered a key step in cementing the deal, which goes into effect 30 days after 55 nations representing 55 percent of all greenhouse gas emissions ratify it. To date, countries representing approximately 50 percent of global emissions have announced that they will submit legal documentation of their compliance with the deal, under which more than 190 nations agreed to keep global warming to within 2 degrees Celsius of pre-industrial levels and to pursue efforts to limit warming to 1.5 Celsius.

“Both leaders feel as if the collaboration between the two leaders was an important element of actually getting Paris successfully negotiated last December,” said Brian Deese, President Obama’s top climate change advisor. “They will both clearly endorse the importance of promoting full implementation of the Paris agreement.”

President Obama indicated that the speed with which the agreement could be brought into force would depend in part on securing “the climate financing that’s necessary for India to be able to embark on a bold vision for solar energy and clean energy” laid out by Modi.

Among the other climate and energy agreements the countries announced was a joint effort to adopt, this year, an amendment to the Montreal Protocol on the use of hydrofluorocarbons (subscription). That amendment would increase financial support to the protocol’s multilateral fund and contain an “aggressive phasedown schedule” for the potent greenhouse gas.

According to a White House fact sheet, other joint efforts include a $40 million program to provide capital for solar projects and a $20 million clean energy finance initiative.

India also agreed to a low greenhouse gas emissions development strategy.

Ontario Unveils Climate Plan with Carbon Market Funding

Yesterday, Ontario announced its climate change action plan for reducing its greenhouse gas emissions by 80 percent from 1990 levels by 2050 and explained how that plan will work with its recently adopted carbon market, which it plans to link with that of California and Quebec in 2018.

According to the Ministry of the Environment and Climate Change, the action plan helps define how market proceeds will be spent. “By law, proceeds must be invested in projects and programs that help reduce greenhouse gas pollution,” said the ministry.

Most of the action plan’s C$8.3 billion in planned spending on combatting climate change will come from the annual C$1.9 billion that the government expects to raise by auctioning greenhouse gas emissions credits.

Canada’s four most populous provinces—representing 86 percent of Canadians—have, or are introducing carbon pricing, either through a carbon tax or a cap-and-trade program aimed at emissions reductions.

The Climate Post offers a rundown of the week in climate and energy news. It is produced each Thursday by Duke University’s Nicholas Institute for Environmental Policy Solutions.

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Climate Change Implicated in a Specific Extreme Weather Event

The Nicholas Institute for Environmental Policy Solutions at Duke University
The Nicholas Institute for Environmental Policy Solutions at Duke University

Scientists have warned that even a few degrees rise in global temperatures can lead to increasingly severe storms. Now an international team of climate scientists has linked man-made climate change to historic flooding that hit the south of England in the winter of 2013–2014. It’s the first time a peer-reviewed research paper has connected climate change to a specific flooding event.

In an article published in Nature Climate Change, the team said that their climate model simulations showed that anthropogenic warming not only increased the amount of moisture the atmosphere can hold but also caused a small but significant increase in the number of January days with westerly flow, both of which increased extreme precipitation. The authors explained that climate change “amplified” the violent storms that led to the area’s wettest January in more than a century and that it has likely increased the number of properties at risk and raised the costs of a flooding event.

Based on more than 130,000 simulations of what the weather would have been like with and without human influence on the climate, the study finds that man-made greenhouse gas emissions have raised the possibility of extreme flooding by 43 percent.

“What was once a 1 in 100-year event in a world without climate change is now a 1 in 70-year event,” said study co-author Friederike Otto of Oxford University.

The study—which analyzed circulation in the atmosphere, the additional risk of rainfall, and swollen river flows and then calculated flood potential in the Thames River Basin—goes beyond previous attempts to connect climate change with specific weather events, tracing connections “all the way from the changes in the atmosphere to the impacts on the ground,” lead author Nathalie Shaller of Oxford University told Agency France Presse.

“This study highlights the fact that we need a better understanding of not just how and where climate change is warming the atmosphere, but also how it is changing patterns of wind and rain, in order to best prepare for extreme rainfall and floods,” said Ted Shepherd, a climate change expert at the University of Reading.

Long-Term Warming Not Unpredictable

Large sustained changes in global temperatures do not rise or fall erratically long term, suggesting the importance of changes in atmospheric circulation and the transfer of energy in balancing Earth’s temperature after a warming event. That’s according to a study published in the Journal of Climate by researchers at Duke University and the National Oceanic and Atmospheric Administration (NASA).

“The bottom line of the study is that the Earth is able to cool itself down after a natural warming event, like an El Nino,” said lead author Patrick Brown, a Duke Ph.D. student. “So then in order to have sustained warming for decades to centuries, you really do need these external drivers, like the increase in greenhouse gases.”

Using global climate models and NASA satellite observations from the last 15 years, the authors cite the Planck Response—the huge increase in infrared energy Earth emits as it warms—for the planet’s capacity to restore the stability of global temperatures. Other important factors, say the authors, are energy transport from the tropic Pacific to polar and continental locations and a net release of energy across cooler regions during unforced, natural warming events.

Studies: East Coast Should Prepare for Warming-Related Sea-Level Rise

Two studies published this week point to regional differences in climate-change-related sea-level rise, specifically, to greater impacts for the U.S. East Coast. A study in Nature Geoscience by researchers at the National Oceanic and Atmospheric Administration (NOAA) finds that “Atlantic coastal areas may be particularly vulnerable to near-future sea-level rise from present-day high greenhouse gas emission rates.” A second study in Proceedings of the National Academy of Sciences finds a higher-than-expected contribution by thermal expansion to sea-level rise from 2002 through 2014—expansion that led to a rapid rise for the East Coast and a slight temporary drop for the Pacific Coast.

Using a climate change model that simulates the ocean, the atmosphere and carbon cycling, the NOAA study examined sea-level rise in the Atlantic, versus that in the Pacific, under multiple global carbon emissions scenarios. It found that if greenhouse gas emissions rates remained consistent with today’s rates, seal levels in the Atlantic would rise much faster than in the Pacific. The difference owes to the Atlantic’s greater “overturning” ocean circulation that connects waters off New York with those off Antarctica. If this circulation slows due to climate change, the researchers concluded that less cold water will dive to ocean depths, warmer water will pool below the surface, and overall warmth will increase. This warm water expands, causing the study’s expected sea level rise, which will have regional variations based on topography and other factors.

The study in the Proceedings of the National Academy of Sciences put the contribution of thermal expansion to rising sea levels at 50 percent. Based largely on satellite readings of changes in water volumes and masses in seas, the study suggests that tallies of the effects of ocean warming on sea-level rise using autonomous seafaring instruments have underestimated thermal expansion.

The Climate Post offers a rundown of the week in climate and energy news. It is produced each Thursday by Duke University’s Nicholas Institute for Environmental Policy Solutions.

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Climate Change Tops WEF Risk Ranking

The Nicholas Institute for Environmental Policy Solutions at Duke University
The Nicholas Institute for Environmental Policy Solutions at Duke University

For the first time, the World Economic Forum (WEF) has ranked an environmental risk—climate change—as the most severe economic risk facing the world. Global Risks Report 2016 says climate change is compounding and intensifying other social, economic, and humanitarian stresses such as mass migration, which it ranked as the threat most likely to materialize in the next 18 months.

“Climate change is exacerbating more risks than ever before in terms of water crises, food shortages, constrained economic growth, weaker societal cohesion and increased security risks,” said Cecilia Reyes, chief risk officer of Zurich Insurance Groups, one of the report collaborators.

Along with interaction with other risks, Margareta Drzeniek-Hanouz, head of global competitiveness and risks at the WEF, pointed to recent weather events and the frequency of natural disasters as justification for climate change’s top ranking this year. “We do see more severe and more likely weather events,” she said. “There are more droughts and floods. We have a higher and higher assessment of climate change.”

Among the priority actions outlined in the report: modifying financial systems to “unleash climate-resilient, low-carbon investments.” The authors found that incentives for such investments have yet to be incorporated into financial decision making despite increasing recognition of climate-change-related economic risks.

The report is based on a survey of 750 experts from economic, environmental, geopolitical, societal, and tech sectors about the perceived impact and likelihood of 29 prevalent global risks over a 10-year period.

Study: Rate of Man-Made Heat Energy Absorbed by Oceans Has Doubled

A new study in the journal Nature Climate Change finds that since 1997 heat uptake by the world’s oceans has nearly doubled by comparison with that uptake in the previous industrial era and that heat is mixing into deeper ocean layers, rather than remaining near the surface.

The study tracked how much man-made heat energy has been buried in the oceans in the past 150 years using ocean-observing data dating as far back as the 1870s. It included readings from high-tech underwater monitors and results of computer models.

Oceans absorb more than 90 percent of man-made heat energy. Since the industrial revolution, deepwater heat content has increased by “several tenths of a degree” when averaged out across the globe, according to Peter Gleckler, the study’s lead author. Although that energy is equivalent to less than 0.5 Celsius of warming averaged across the upper reaches of the ocean, Gleckler said it is still a “huge increase,” adding that “if we want to really understand how much heat is being trapped, we can’t just look at the upper ocean anymore, we need to look deeper.”

The study found that a third of the recent ocean heat buildup occurred at depths of 700 meters or greater, possibly explaining a pause in warming at the sea surface since the end of the 20th century. Why deeper waters may be absorbing greater amounts of heat is not fully understood, according to the study.

The University of California reported that the Nature Climate Change study “found that estimates of ocean warming over a range of times and depths are consistent with results from the latest generation of climate models, building confidence that the climate models are providing useful information.”

Official Numbers: 2015 Was the Hottest Year

Independent analyses by the National Oceanic and Atmospheric Administration (NOAA), the Goddard Institute for Space Studies at the National Aeronautics and Space Administration (NASA), and the U.K. Met Office found that Earth’s surface temperatures were the warmest they have been since record-keeping began.

NASA calculated the rise at 0.23 degree Fahrenheit above 2014 and suggested that 1998 was the only year that a new record was greater than the old record by such a large margin. NOAA put the increase at 0.29 degree Fahrenheit. The U.K. Met Office expects 2016 to set another record.

“A lot of times, you actually look at these numbers, when you break a record, you break it by a few hundredths of a degree,” said Thomas Karl, director of NOAA’s National Centers for Environmental Information. “But this record, we literally smashed. It was over a quarter of a degree Fahrenheit, and that’s a lot for the global temperature.”

Although 2015 temperatures were assisted by an ongoing El Nino weather pattern—which brings heat from the Pacific Ocean into the atmosphere, Gavin Schmidt, director of NASA’s Goddard Institute for Space Studies said “it is the cumulative effect of the long-term trend that has resulted in the record warming that we are seeing.”

NASA used surface temperature measurements from more than 6,000 weather and research stations as well as ship- and buoy-based observations of sea surface temperatures for its analysis. NOAA uses similar temperature data, but it also uses different baseline periods and methods.

The Climate Post offers a rundown of the week in climate and energy news. It is produced each Thursday by Duke University’s Nicholas Institute for Environmental Policy Solutions.

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Obama May Use Executive Power to Forge International Climate Change Deal as U.N. Draft Report Paints Stark Climate Picture

The Nicholas Institute for Environmental Policy Solutions at Duke University
The Nicholas Institute for Environmental Policy Solutions at Duke University

A leaked draft of a report by the United Nations Intergovernmental Panel on Climate Change (IPCC) warns that global warming is already affecting all continents and that additional pollution from heat-trapping gases will worsen the situation.

“Continued emission of greenhouse gases will cause further warming and long-lasting changes in all components of the climate system, increasing the likelihood of severe, pervasive and irreversible impacts for people and ecosystems,” the report stated.

The document is the final piece of the IPCC’s Fifth Assessment Report, which synthesizes earlier reports on climate change. The report will not be released until its review at a conference in Copenhagen later this fall.

President Obama doesn’t appear interested in waiting to take action against climate change. Media are reporting that he is planning to use his executive powers—sidestepping the two-thirds Senate vote required for a legally binding treaty—to forge another sort of international deal to cut greenhouse gas emissions.

The “politically binding” deal, which The New York Times reports will be signed at the United Nations Summit Meeting in Paris next year, is intended to “name and shame” countries into cutting emissions. Negotiators are working to implement the deal, which would commit every signatory nation to achieving specific carbon reduction goals and to sending money to poorer nations to address the effects of climate. These “fresh voluntary pledges” would be mixed with legally binding 1992 treaty conditions.

But a State Department official said it was premature to say for certain that Obama will bypass Congress.

“Not a word of the new climate agreement currently under discussion has been written, so it is entirely premature to say whether it will or won’t require Senate approval,” said Jen Psaki, State Department spokeswoman. “Our goal is to negotiate a successful and effective global climate agreement that can help address this pressing challenge. Anything that is eventually negotiated and that should go to the Senate will go to the Senate.”

Methane “Seeps” Could Effect Ocean Temperatures

Methane, a gas about 20 times more powerful than carbon dioxide, is leaking from deep-sea vents off the East Coast where the Continental Shelf meets the deeper Atlantic Ocean. The newly released Nature study found more than 550 of these “seeps,” which are thought to be fed by methane stored in hydrates—described by Science as crystal lattices of water ice that form under low temperatures and high pressures.

Until now, previous surveys had found only three such seeps.

“It is the first time we’ve seen this level of seepage outside the Arctic that is not associated with features like oil and gas reservoirs or active tectonic margins,” said Adam Skarke, lead author of the study. “This is a large amount of methane seepage in an area we didn’t expect.”

The seeps were discovered, according to the study, at depths that are typically more stable for gas hydrate. Although the methane likely didn’t reach the atmosphere, it could affect ocean acidity.

“Warming of the ocean waters could cause this ice to melt and release gas,” said Skarke. “So there may be some connection here to intermediate ocean warming, though we need to carry out further investigations to confirm if that is the case.”

EPA Report Says Cities Getting Cleaner

The second of two reports required under the Clean Air Act to inform Congress of progress in reducing urban air toxins is out. It finds that since enactment of the Clean Air Act amendments of 1990 the U.S. Environmental Protection Agency (EPA) has made significant progress in reducing these toxins:

  • Coal-fired power plants and other manmade sources have decreased toxic mercury emissions by about 60 percent.
  • Cancer-causing benzene has been reduced by 66 percent.
  • Lead in outdoor air is down 84 percent.
  • An estimated 1.5 million tons per year of air toxics has been removed from mobile sources, which represents a 50 percent reduction in mobile-source air toxics emissions.

“But we know our work is not done yet,” said EPA administrator Gina McCarthy. “At the core of EPA’s mission is environmental justice—striving for clean air, water and healthy land for every American; and we are committed to reducing remaining pollution, especially in low-income neighborhoods.”

The report cited six areas in which the EPA’s air toxics program could improve, including research on the health impacts of air toxics and collection of data in more areas covering more ambient pollutants.

The Climate Post offers a rundown of the week in climate and energy news. It is produced each Thursday by Duke University’s Nicholas Institute for Environmental Policy Solutions.