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More Evidence on Ocean Acidification

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More evidence on the imminent danger of ocean acidification was published last month. The study from Bristol University warned that acidification is progressing faster than at any time during the past 65 million years, with potentially devastating effects for marine ecosystems. According to the paper’s abstract:

In our simulation of future ocean conditions, we find an undersaturation with respect to carbonate in the deep ocean that exceeds that experienced during the Palaeocene–Eocene thermal maximum and could endanger calcifying organisms. Furthermore, our simulations show higher rates of environmental change at the surface for the future than the Palaeocene–Eocene thermal maximum, which could potentially challenge the ability of plankton to adapt.

During the Palaeocene-Eocene extinction, bottom-dwelling organisms were disproportionately impacted, with surface-dwelling plankton relatively unaffected. This time around, though, things might be different. The speed of acidification (estimated to be 10 times faster than previous events) will prevent many of the adaptations that prevented even greater extinctions in the past.

Ocean Acidification

Ocean acidification will destroy coral reefs

So why is this relevant? The main reason is that many of the small marine calcifiers affected by ocean acidification form the foundation of the ocean food web. And if their numbers collapse, what will happen further up the chain? And what will happen to us?

Finally, remember these important points:

Acidification of the oceans has been called “the other carbon dioxide problem”, as it is not directly related to global warming or climate change, but rather the increasing amounts of carbon dioxide dissolved in seawater.

Geoengineering schemes that aim to cool the planet without removing CO2 from the atmosphere will have no effect on ocean pH

The accelerating rate of acidification makes it likely that major marine structures like Australia’s Great Barrier Reef will stop growing and start dissolving by 2050.

Although climate change skeptics might point out that coral reefs have survived past CO2 peaks, it is the speed of change (preventing migration and genetic adaptation) and the inability of the oceans to buffer increasing amounts of carbon dioxide, that have the potential to cause a mass extinction.

See the paper’s abstract here. Read a related editorial at the YALE 360 site called An Ominous Warning on the Effects of Ocean Acidification. Photo by Tom Clifton/flickr.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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EPA: Clean Water Act could be used to slow ocean acidification

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pteropod

Ocean acidification significantly impairs shell-formation in marine calcifiers, including coral reefs and shellfish.

NEW YORK TIMES: States bordering water bodies that are becoming more acidic from the absorption of carbon dioxide should list them as impaired under the Clean Water Act, the Environmental Protection Agency declared in a memo this week.

Carbon dioxide emissions are considered a threat not only because of their heat-trapping properties in the atmosphere but also because of their ability to change ocean chemistry. The world’s oceans act as a sponge for carbon dioxide, and as the gas dissolves in seawater, it changes into carbonic acid. Read full article…..

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Interview: Australia’s Chief Scientist launches sustainability reports, calls for food security and nuclear power

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Australia’s chief scientist, Professor Penny Sackett, tells Lateline we need to look at a broad suite of technological and scientific solutions to secure supplies of food, energy and water for the future. Read transcript and watch video.

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Four degrees and beyond – new research highlights dangers of runaway climate change

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Transactions of the Royal Society A - The Four Degree World

The Four Degree World

ABC SCIENCE: A collection of papers published last week (Philosophical Transactions Of The Royal Society A) examine the impact global warming may have on weather patterns, food production and population by the end of this century.

Since the late 1990s, many researchers and policy makers have held a 2°C global temperature increase relative to pre-industrial times as a benchmark limit for global warming, saying that keeping warming below this threshold increases the likelihood that catastrophic changes can be avoided.

But it appears we are unlikely to meet that target, say researchers, and an average global warming of 4°C by the end of this century is more likely.

A study by Richard Betts (Hadley Centre) suggests that a 4°C rise relative to pre-industrial levels could happen by the 2070s, if emissions are high, if the temperature response to those emissions is high, and if the feedback cycles to those emissions are high.

If we reach 4°C higher by the 2070s, it would put us on track for an almost 7°C increase by the end of the century, he says. The projections are too uncertain to say exactly what trajectory we are on, says Betts.

“I don’t particularly sign up to the fact that 2°C is some kind of threshold for catastrophic climate change,” he says. “It’s all about risk assessment. The greater the warming, the larger the impact. The faster the warming, the harder it is to adapt to any impact. The risk becomes greater the more you put into the system.”

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ABC Science story

Philosophical Transactions Of The Royal Society A – original articles, many free access.

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Ancient climate change drove reptile evolution

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Rainforest dieback due to a warming climate drove reptile evolution 300 million years ago.

Rainforest dieback due to a warming climate drove reptile evolution 300 million years ago.

ABC SCIENCE (AUSTRALIA): A dramatic climate change event which devastated Earth’s rainforests just under 300 million years ago also opened the way for the rise of the reptiles, a new study shows.

“We can conclude that life is resilient to climate change, even the collapse of rainforests”, he says, “but not without devastating loss of diversity and a change in the direction of evolution.

“If rainforests were to collapse today, life on Earth would never be the same again. But given sufficient time, new forms would evolve in the new environment that followed What might replace it is uncertain.”

Read More…..

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Can more reflective crops reduce global warming?

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Can planting more reflective crops lower global warming?

Can planting more reflective crops lower global warming?

DISCOVERY NEWS: Planting more reflective versions of crops could cool regional temperatures in summertime, reducing the impact of increasing global temperatures in these areas, according to ongoing research.

Increasing the reflectivity of crop plants by 20 percent could decrease temperatures in a given area by about one degree Celsius (1.8 degrees Fahrenheit), said Joy Singarayer of the University of Bristol, United Kingdom.

“It’s quite immediate and it’s quite safe because crops get planted every year,” she said. ”The idea is not to think about changing what crops you plant but rather to look within the variety of crops you might plant.” This might mean choosing a more reflective variety of wheat, for example. More…

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Earth’s Lakes are Warming Fast In Response To Climate Change

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PASADENA (23.11.2010) – In the first comprehensive global survey of temperature trends in major lakes, NASA researchers determined Earth’s largest lakes have warmed during the past 25 years in response to climate change.

Researchers Philipp Schneider and Simon Hook of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., used satellite data to measure the surface temperatures of 167 large lakes worldwide.

Many lakes worldwide are warming faster than the atmosphere according to new NASA study.

Many lakes worldwide are warming faster than the atmosphere according to new NASA study.

“Our analysis provides a new, independent data source for assessing the impact of climate change over land around the world,” said Schneider, lead author of the study published this week in the journal Geophysical Research Letters. “The results have implications for lake ecosystems, which can be adversely affected by even small water temperature changes.”

Small changes in water temperature can result in algal blooms that can make a lake toxic to fish or result in the introduction of non-native species that change the lake’s natural ecosystem.

They reported an average warming rate of 0.45 degrees Celsius (0.81 degrees Fahrenheit) per decade, with some lakes warming as much as 1 degree Celsius (1.8 degrees Fahrenheit) per decade. The warming trend was global, and the greatest increases were in the mid- to high-latitudes of the Northern Hemisphere.

Scientists have long used air temperature measurements taken near Earth’s surface to compute warming trends. More recently, scientists have supplemented these measurements with thermal infrared satellite data that can be used to provide a comprehensive, accurate view of how surface temperatures are changing worldwide.

The NASA researchers used thermal infrared imagery from National Oceanic and Atmospheric Administration and European Space Agency satellites. They focused on summer temperatures (July to September in the Northern Hemisphere and January to March in the Southern Hemisphere) because of the difficulty in collecting data in seasons when lakes are ice-covered and/or often hidden by clouds. Only nighttime data were used in the study.

The bodies studied were selected from a global database of lakes and wetlands based on size (typically at least 500 square kilometers – 193 square miles – or larger) or other unique characteristics of scientific merit. The selected lakes also had to have large surface areas located away from shorelines, so land influences did not interfere with the measurements. Satellite lake data were collected from the point farthest from any shoreline.

The largest and most consistent area of warming was northern Europe. The warming trend was slightly weaker in southeastern Europe, around the Black and Caspian seas and Kazakhstan. The trends increased slightly farther east in Siberia, Mongolia and northern China.

In North America, trends were slightly higher in the southwest United States than in the Great Lakes region. Warming was weaker in the tropics and in the mid-latitudes of the Southern Hemisphere. The results were consistent with the expected changes associated with global warming.

The satellite temperature trends largely agreed with trends measured by nine buoys in the Great Lakes, Earth’s largest group of freshwater lakes in terms of total surface area and volume.

Lake Tahoe

Lake Tahoe, seen here from Emerald Bay, was one of the primary validation sites for the global lake study. The lake, which straddles the borders of California and Nevada, is the largest alpine lake in North America.

The lake temperature trends were also in agreement with independent surface air temperature data from NASA’s Goddard Institute for Space Studies in New York. In certain regions, such as the Great Lakes and northern Europe, water bodies appear to be warming more quickly than surrounding air temperature.

Source and image credits: NASA.

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Local Government Taking The Lead On Climate Change Mitigation

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In the lead-up to Cancun it is becoming clear that many local government authorities are increasingly frustrated at global delays on climate change mitigation, instead preferring to lead the charge on GHG reduction in their own jurisdictions.

And this is especially true of many megacity administrations. Such places (like Mexico City, Los Angeles and Seoul) have larger populations, own more utility services and produce more GHGs than many small countries, yet have little representation or influence on UN or national climate negotiations.

Megacities like Mexico City are leading the way on global warming mitigation.

Megacities like Mexico City are leading the way on global warming mitigation.

In preparation for the Cancun climate meeting the World Mayors Summit on Climate (organized by Mexico City Mayor Marcelo Ebrard) has become a forum not only for the initiatives cities have taken to reduce emissions but also for the frustrations the urban leaders feel at being locked out of planning and financing for broader, deeper programs.

This is despite the fact that cities play an absolutely strategic role in the fight against climate change – Despite controlling policies on transportation, water, waste management, street lighting and other essential but energy-intensive civil services, mayors were left on the sidelines of the Copenhagen summit last November. “Copenhagen was a fiasco. There was no real outcome,” according to Kadir Topbas, mayor of Istanbul. “The planet is giving us very bad signals”.

Unfortunately few expect the Cancun meeting to make progress toward an agreement on emissions reductions, but as nations delay, hundreds of cities are pledging to rein in emissions, slash energy usage, and turn to renewable energy sources.

The potential for cities to reduce GHG emissions is massive, and they have already started to do just that, rather than wait for national governments to take the lead. Los Angeles, for example is replacing 144,000 streetlights with efficient LED lamps, ditching diesel trucks, recycling 65 percent of its garbage and moving to become the electric vehicle capital of the United States by the end of 2011 according to Mayor Antonio Villaraigosa.

Such megacities consume as much as 60 percent of global energy production and emit 70 percent of greenhouse gases, as well as housing half of the world’s population, according to David Cadman (head of Local Governments for Sustainability – a group with 1,200 cities, towns, counties and associations among its members).

So it appears that there is an emerging grassroots movement to act on climate change and the release of GHGs – if national governments aren’t going to deliver then local (and some state) governments might.

And as they push ahead with reforms, there should be a percolation of ideas and actions upwards through the layers of government until the cream, or perhaps the methane, rises to the top. And as it is local residents (at least in the developed world) that can meet their representatives face-to-face, there is reason for real optimism that one person can make a difference.

Image Credit: Jose Ramon Vega

Story Credit: Tim Johnson

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Call for doctors to take the lead on climate change

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Doctors should take the lead in practical steps to reduce the carbon footprints associated with obesity, chronic disease and population growth, according to an article published in the Medical Journal of Australia and reported on the AMA website in May.

Doctors and other healthcare professionals must take the lead in raising climate change awareness.

Doctors and other healthcare professionals must take the lead in raising climate change awareness.

Prof Robyn McDermott, Professor of Public Health at the University of South Australia, writes that ageing, obesity and associated conditions account for the greatest proportion of disability and accelerating health care use, and that the health sector itself has a significant and expanding carbon footprint.

“When we add the increasing costs of health care and the health industry’s carbon footprint to the entirely preventable loss of years of life and wellness caused by physical inactivity, we have a compelling case for specific action led by doctors in four health-related domains,” Prof McDermott said.

These four areas include reducing the adverse environmental impact of the health care industry; developing a comprehensive food and nutrition policy that addresses food quality, safety and security; upgrading urban planning rules to make climate change mitigation measures enforceable; and supporting more robust policies to protect the sexual health and reproductive rights of women globally to improve overall quality of life and indirectly slow population growth.

Climate change policies should be assessed for their impact on global health and equity.

In an accompanying editorial, Associate Prof Colin Butler, from the National Centre for Epidemiology and Population Health at the Australian National University, acknowledges that doctors are powerful role models, but says that the virtual absence of health as an agenda item for the recent climate change talks in Copenhagen underlines how far there is to go.

“It is … easy to call for “whole-of-government” approaches, whether to slow climate change, fix the obesogenic environment or to enhance equity. Easy to say, hard to achieve,” Prof Butler said.

“The law of increasing returns [how groups with influence are able to rig public opinion and legislate to benefit powerful minorities rather than the public good] is a powerful impediment, not only to whole-of-government reforms, but to the transition to sustainability more broadly.”

The Medical Journal of Australia is a publication of the Australian Medical Association.

Source: AMA

Image credit: flickr / wenzday01

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Arctic warming accelerating according to new report

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*See related video at the bottom of page*

This year’s Arctic Report Card from NOAA is in, and the grades aren’t good. The theme for this year is that it is clear that the Arctic is experiencing the impacts of a prolonged and amplified warming trend, highlighted with many record-setting events. The report also reminds us that deviations from the average air temperature are amplified by a factor of two or more in the Arctic relative to lower latitudes.

Walrus and other iconic species are at high risk due to prolonged Arctic warming.

Walrus and other iconic species are at high risk due to prolonged Arctic warming.

To this I would add that it is now apparent (due to the inertia inherent in the global climate system) that the  warming effects currently being observed are due to the greenhouse gasses released 30-40 years ago -back when climate change was barely known to the general public. The amount of warming built into the system (based on real-world observations like the ones in this report) that is still to come is quite terrifying – suggesting to me that the most recent IPCC predictions for warming and sea-level rise are remarkably optimistic (let alone the claims of the climate denialists!).

It is also worth noting that while a reduction in the ice-albedo effect leading to enhanced warming is described, accelerated GHG release from thawing permafrost, along with methane hydrates, are not mentioned in this report card (despite the evidence that permafrost is warming up around the Arctic rim). Either could act as additional positive feedback mechanisms – causing accelerated warming – if and when large amounts of gas are released (UPDATE – New article about accelerated methane release from permafrost).

Now to the findings of the report card. The “highlights” include:

*A new record minimum in springtime snow cover duration.

*Increased permafrost temperatures around the Arctic rim.

*Increased river discharge to the Arctic Ocean (could this affect the thermohaline circulation?)

*Increased greenness of Arctic vegetation.

Sea Ice

The Arctic summer sea ice extent and mass is rapidly decreasing.

The Arctic summer sea ice extent and mass is rapidly decreasing.

*September Arctic sea ice extent was the third smallest of the past 30 years (the four smallest recorded September ice extents have occurred in the past four years, and eight of the ten lowest summer minimums have occurred in the last decade).

*Third smallest ever extent of older, thicker multiyear ice.

*Both the Northern Sea Route and the Northwest Passage were ice-free in September.

Greenland

*Record warm air temperatures were observed over Greenland in 2010. This included the warmest year on record for Greenland’s capital, Nuuk, in at least 138 years.

*Melt period on Greenland’s inland ice sheet 1 month longer than the 30 year average.

*Glacier loss along the Greenland margins was also exceptional in 2010, with the largest single glacier area loss (110 square miles, at Petermann glacier) equivalent to an area four times that of Manhattan Island.

“There is now no doubt that Greenland ice losses have not just increased above past decades, but have accelerated – the implication is that sea level rise projections will again need to be revised upward.”

Outcomes

“It is increasingly unlikely (at least for the foreseeable future) that the Arctic will return to conditions that were considered normal in the later part of the 20th century…and very likely that Arctic climate warming will continue and we will continue to see records set in years to come.”

*Progressive reduction in the ice albedo effect, exposing darker ocean and increasing heat absorption – this in turn leads to accelerated melting and a progressive acceleration of this cycle (in a classical example of positive feedback).

*With the expectation of continued warming air temperatures, Arctic species that have adapted to the Arctic environments are expected to be displaced by the encroachment of more southerly (sub-Arctic) species and ecosystems.

“While we see somewhat direct relationships between warming and ice cover melt, it is more difficult, due to the complex nature of ecosystems, to predict and understand how these biological systems are and will respond to this amplified warming trend.”

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