by Deep Green Resistance News Service | Jan 19, 2013 | Climate Change
By NASA Jet Propulsion Laboratory
An area of the Amazon rainforest twice the size of California continues to suffer from the effects of a megadrought that began in 2005, finds a new NASA-led study. These results, together with observed recurrences of droughts every few years and associated damage to the forests in southern and western Amazonia in the past decade, suggest these rainforests may be showing the first signs of potential large-scale degradation due to climate change.
An international research team led by Sassan Saatchi of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., analyzed more than a decade of satellite microwave radar data collected between 2000 and 2009 over Amazonia. The observations included measurements of rainfall from NASA’s Tropical Rainfall Measuring Mission and measurements of the moisture content and structure of the forest canopy (top layer) from the Seawinds scatterometer on NASA’s QuikScat spacecraft.
The scientists found that during the summer of 2005, more than 270,000 square miles (700,000 square kilometers, or 70 million hectares) of pristine, old-growth forest in southwestern Amazonia experienced an extensive, severe drought. This megadrought caused widespread changes to the forest canopy that were detectable by satellite. The changes suggest dieback of branches and tree falls, especially among the older, larger, more vulnerable canopy trees that blanket the forest.
While rainfall levels gradually recovered in subsequent years, the damage to the forest canopy persisted all the way to the next major drought, which began in 2010. About half the forest affected by the 2005 drought – an area the size of California – did not recover by the time QuikScat stopped gathering global data in November 2009 and before the start of a more extensive drought in 2010.
“The biggest surprise for us was that the effects appeared to persist for years after the 2005 drought,” said study co-author Yadvinder Malhi of the University of Oxford, United Kingdom. “We had expected the forest canopy to bounce back after a year with a new flush of leaf growth, but the damage appeared to persist right up to the subsequent drought in 2010.”
Recent Amazonian droughts have drawn attention to the vulnerability of tropical forests to climate change. Satellite and ground data have shown an increase in wildfires during drought years and tree die-offs following severe droughts. Until now, there had been no satellite-based assessment of the multi-year impacts of these droughts across all of Amazonia. Large-scale droughts can lead to sustained releases of carbon dioxide from decaying wood, affecting ecosystems and Earth’s carbon cycle.
The researchers attribute the 2005 Amazonian drought to the long-term warming of tropical Atlantic sea surface temperatures. “In effect, the same climate phenomenon that helped form hurricanes Katrina and Rita along U.S. southern coasts in 2005 also likely caused the severe drought in southwest Amazonia,” Saatchi said. “An extreme climate event caused the drought, which subsequently damaged the Amazonian trees.”
Saatchi said such megadroughts can have long-lasting effects on rainforest ecosystems. “Our results suggest that if droughts continue at five- to 10-year intervals or increase in frequency due to climate change, large areas of the Amazon forest are likely to be exposed to persistent effects of droughts and corresponding slow forest recovery,” he said. “This may alter the structure and function of Amazonian rainforest ecosystems.”
The team found that the area affected by the 2005 drought was much larger than scientists had previously predicted. About 30 percent (656,370 square miles, or 1.7 million square kilometers) of the Amazon basin’s total current forest area was affected, with more than five percent of the forest experiencing severe drought conditions. The 2010 drought affected nearly half of the entire Amazon forest, with nearly a fifth of it experiencing severe drought. More than 231,660 square miles (600,000 square kilometers) of the area affected by the 2005 drought were also affected by the 2010 drought. This “double whammy” by successive droughts suggests a potentially long-lasting and widespread effect on forests in southern and western Amazonia.
The drought rate in Amazonia during the past decade is unprecedented over the past century. In addition to the two major droughts in 2005 and 2010, the area has experienced several localized mini-droughts in recent years. Observations from ground stations show that rainfall over the southern Amazon rainforest declined by almost 3.2 percent per year in the period from 1970 to 1998. Climate analyses for the period from 1995 to 2005 show a steady decline in water availability for plants in the region. Together, these data suggest a decade of moderate water stress led up to the 2005 drought, helping trigger the large-scale forest damage seen following the 2005 drought.
Saatchi said the new study sheds new light on a major controversy that existed about how the Amazon forest responded following the 2005 megadrought. Previous studies using conventional optical satellite data produced contradictory results, likely due to the difficulty of correcting the optical data for interference by clouds and other atmospheric conditions.
In contrast, QuikScat’s scatterometer radar was able to see through the clouds and penetrate into the top few meters of vegetation, providing daily measurements of the forest canopy structure and estimates of how much water the forest contains. Areas of drought-damaged forest produced a lower radar signal than the signals collected over healthy forest areas, indicating either that the forest canopy is drier or it is less “rough” due to damage to or the death of canopy trees.
From NASA Jet Propulsion Laboratory: http://www.jpl.nasa.gov/news/news.php?release=2013-025
by Deep Green Resistance News Service | Jan 8, 2013 | Climate Change
By Justin Gillis / The New York Times
The numbers are in: 2012, the year of a surreal March heat wave, a severe drought in the corn belt and a massive storm that caused broad devastation in the mid-Atlantic states, turns out to have been the hottest year ever recorded in the contiguous United States.
How hot was it? The temperature differences between years are usually measured in fractions of a degree, but last year blew away the previous record, set in 1998, by a full degree Fahrenheit.
If that does not sound sufficiently impressive, consider that 34,008 new daily high records were set at weather stations across the country, compared with only 6,664 new record lows, according to a count maintained by the Weather Channel meteorologist Guy Walton, using federal temperature records.
That ratio, which was roughly in balance as recently as the 1970s, has been out of whack for decades as the country has warmed, but never by as much as it was last year.
“The heat was remarkable,” said Jake Crouch, a scientist with the National Climatic Data Center in Asheville, N.C., which released the official climate compilation on Tuesday. “It was prolonged. That we beat the record by one degree is quite a big deal.”
Scientists said that natural variability almost certainly played a role in last year’s extreme heat and drought. But many of them expressed doubt that such a striking new record would have been set without the backdrop of global warming caused by the human release of greenhouse gases. And they warned that 2012 was likely a foretaste of things to come, as continuing warming makes heat extremes more likely.
Even so, the last year’s record for the United States is not expected to translate into a global temperature record when figures are released in coming weeks. The year featured a La Niña weather pattern, which tends to cool the global climate over all, and scientists expect it to be the world’s eighth or ninth warmest year on record.
Assuming that prediction holds up, it will mean that the 10 warmest years on record all fell within the past 15 years, a measure of how much the planet has warmed. Nobody who is under 28 has lived through a month of global temperatures that fell below the 20th-century average, because the last such month was February 1985.
Last year’s weather in the United States began with an unusually warm winter, with relatively little snow across much of the country, followed by a March that was so hot that trees burst into bloom and swimming pools opened early. The soil dried out in the March heat, helping to set the stage for a drought that peaked during the warmest July on record.
The drought engulfed 61 percent of the nation, killed corn and soybean crops and sent prices spiraling. It was comparable to a severe drought in the 1950s, Mr. Crouch said, but not quite as severe as the legendary Dust Bowl drought of the 1930s, which was exacerbated by poor farming practices that allowed topsoil to blow away.
Extensive records covering the lower 48 states go back to 1895; Alaska and Hawaii have shorter records and are generally not included in long-term climate comparisons for that reason.
Mr. Crouch pointed out that until last year, the coldest year in the historical record for the lower 48 states, 1917, was separated from the warmest year, 1998, by only 4.2 degrees Fahrenheit. That is why the 2012 record, and its one degree increase over 1998, strikes climatologists as so unusual.
“We’re taking quite a large step above what the period of record has shown for the contiguous United States,” he said.
In addition to being the nation’s warmest year, 2012 turned out to be the second-worst on a measure called the Climate Extremes Index, surpassed only by 1998.
Read more from The New York Times: http://www.nytimes.com/2013/01/09/science/earth/2012-was-hottest-year-ever-in-us.html?_r=0
by Deep Green Resistance News Service | Jan 5, 2013 | Climate Change, Mining & Drilling
By Joe Romm / Think Progress
Researchers with the National Oceanic and Atmospheric Administration (NOAA) have reconfirmed earlier findings of high rates of methane leakage from natural gas fields. If these findings are replicated elsewhere, they would utterly vitiate the climate benefit of natural gas, even when used to switch off coal.
Indeed, if the previous findings — of 4% methane leakage over a Colorado gas field — were a bombshell, then the new measurements reported by the journal Nature are thermonuclear:
… the research team reported new Colorado data that support the earlier work, as well as preliminary results from a field study in the Uinta Basin of Utah suggesting even higher rates of methane leakage — an eye-popping 9% of the total production. That figure is nearly double the cumulative loss rates estimated from industry data — which are already higher in Utah than in Colorado.
The Uinta Basin is of particular interest because fracking has increased there over the past decade.
How much methane leaks during the entire lifecycle of unconventional gas has emerged as a key question in the fracking debate. Natural gas is mostly methane (CH4). And methane is a far more potent greenhouse gas than (CO2), which is released when any hydrocarbon, like natural gas, is burned — 25 times more potent over a century and 72 to 100 times more potent over a 20-year period.
Even without a high-leakage rate for shale gas, we know that “Absent a Serious Price for Global Warming Pollution, Natural Gas Is A Bridge To Nowhere.” That was first demonstrated by the International Energy Agency in its big June 2011 report on gas — see IEA’s “Golden Age of Gas Scenario” Leads to More Than 6°F Warming and Out-of-Control Climate Change. That study — which had both coal and oil consumption peaking in 2020 — made abundantly clear that if we want to avoid catastrophic warming, we need to start getting off of all fossil fuels.
A March 2012 study by climatologist Ken Caldeira and tech guru Nathan Myhrvold came to a similar conclusion using different methodology (see “You Can’t Slow Projected Warming With Gas, You Need ‘Rapid and Massive Deployment’ of Zero-Carbon Power“). They found that even if you could switch entirely over to natural gas in four decades, you “won’t see any substantial decrease in global temperatures for up to 250 years. There’s almost no climate value in doing it.” And that was using conventional (i.e. low) leakage rates.
But the leakage rate does matter. A major 2011 study by Tom Wigley of the Center for Atmospheric Research (NCAR) concluded:
The most important result, however, in accord with the above authors, is that, unless leakage rates for new methane can be kept below 2%, substituting gas for coal is not an effective means for reducing the magnitude of future climate change.
Wigley, it should be noted, was looking at the combined warming impact from three factors — from the methane leakage, from the gas plant CO2 emissions, and from the drop in sulfate aerosols caused by switching out coal for gas. In a country like the United States, which strongly regulates sulfate aerosols, that third factor is probably much smaller. Of course, in countries like China and India, it would be a big deal.
An April 2012 study found that a big switch from coal to gas would only reduce “technology warming potentials” by about 25% over the first three decades — far different than the typical statement that you get a 50% drop in CO2 emissions from the switch. And that assumed a total methane leakage of 2.4% (using EPA’s latest estimate). The study found that if the total leakage exceeds 3.2% “gas becomes worse for the climate than coal for at least some period of time.”
Leakage of 4%, let alone 9%, would call into question the value of unconventional gas as any sort of bridge fuel. Colm Sweeney, the head of the aircraft program at NOAA’s Earth System Research Laboratory, who led the study’s aerial component, told Nature:
“We were expecting to see high methane levels, but I don’t think anybody really comprehended the true magnitude of what we would see.”
The industry has tended to keep most of the data secret while downplaying the leakage issue. The Environmental Defense Fund (EDF) is working with the industry to develop credible leakage numbers in a variety of locations.
The earlier NOAA findings were called into question by Michael Levi of the Council on Foreign Relations. The NOAA researchers “have a defence of the Colorado study in press,” Nature notes.
Right now, fracking would seem to be a bridge to nowhere.
From Think Progress: http://thinkprogress.org/climate/2013/01/02/1388021/bridge-to-nowhere-noaa-confirms-high-methane-leakage-rate-up-to-9-from-gas-fields-gutting-climate-benefit/
Banner: US Environmental Protection Agency, Office of Research and Development, Washington, DC, Public domain, via Wikimedia Commons
by Deep Green Resistance News Service | Dec 27, 2012 | Biodiversity & Habitat Destruction
By Agence France-Presse
China’s economic boom has seen its coral reefs shrink by at least 80 percent over the past 30 years, according to a joint Australian study, with researchers describing “grim” levels of damage and loss.
Scientists from the Australian Research Council Centre of Excellence for Coral Reef Studies and the South China Sea Institute of Oceanology said their survey of mainland China and South China Sea reefs showed alarming degradation.
“We found that coral abundance has declined by at least 80 percent over the past 30 years on coastal fringing reefs along the Chinese mainland and adjoining Hainan Island,” said the study, published in the latest edition of the journal Conservation Biology.
“On offshore atolls and archipelagos claimed by six countries in the South China Sea, coral cover has declined from an average of greater than 60 percent to around 20 percent within the past 10-15 years,” it added.
Coastal development, pollution and overfishing linked to the Asian giant’s aggressive economic expansion were the major drivers, the authors said, describing a “grim picture of decline, degradation and destruction”.
“China’s ongoing economic expansion has exacerbated many wicked environmental problems, including widespread habitat loss due to coastal development, unsustainable levels of fishing, and pollution,” the study said.
Coral loss in the South China Sea — where reefs stretch across some 30,000 square kilometres (12,000 square miles) — was compounded by poor governance stemming from competing territorial claims.
Some marine parks aimed at conservation had been established but study author Terry Hughes said they were too small and too far apart to arrest the decline in coral cover.
“The window of opportunity to recover the reefs of the South China Sea is closing rapidly, given the state of degradation revealed in this study,” he said.
The South China Sea is strategically significant, home to some of the world’s most important shipping lanes and believed to be rich in resources.
China claims most of the sea including waters close to the shores of its neighbours. Rival claimants include Brunei, Malaysia, the Philippines and Vietnam, and tensions over the issue have flared in recent years.
From The Raw Story: http://www.rawstory.com/rs/2012/12/26/study-coral-reefs-decimated-by-chinese-economic-boom/
by Deep Green Resistance News Service | Dec 20, 2012 | Biodiversity & Habitat Destruction, Climate Change
By United States Geological Survey
Plant and animal species are shifting their geographic ranges and the timing of their life events – such as flowering, laying eggs or migrating – at faster rates than researchers documented just a few years ago, according to a technical report on biodiversity and ecosystems used as scientific input for the 2013 Third National Climate Assessment.
The report, Impacts of Climate Change on Biodiversity, Ecosystems, and Ecosystem Services, synthesizes the scientific understanding of the way climate change is affecting ecosystems, ecosystem services and the diversity of species, as well as what strategies might be used by natural resource practitioners to decrease current and future risks. More than 60 federal, academic and other scientists, including the lead authors from the U.S. Geological Survey, the National Wildlife Federation and Arizona State University in Tempe, authored the assessment.
“These geographic range and timing changes are causing cascading effects that extend through ecosystems, bringing together species that haven’t previously interacted and creating mismatches between animals and their food sources,” said Nancy Grimm, a scientist at ASU and a lead author of the report.
Grimm explained that such mismatches in the availability and timing of natural resources can influence species’ survival; for example, if insects emerge well before the arrival of migrating birds that rely on them for food, it can adversely affect bird populations. Earlier thaw and shorter winters can extend growing seasons for insect pests such as bark beetles, having devastating consequences for the way ecosystems are structured and function. This can substantially alter the benefits people derive from ecosystems, such as clean water, wood products and food.
“The impact of climate change on ecosystems has important implications for people and communities,” said Amanda Staudt, a NWF climate scientist and a lead author on the report. “Shifting climate conditions are affecting valuable ecosystem services, such as the role that coastal habitats play in dampening storm surge or the ability of our forests to provide timber and help filter our drinking water.”
Another key finding is the mounting evidence that population declines and increased extinction risks for some plant and animal species can be directly attributed to climate change. The most vulnerable species are those already degraded by other human-caused stressors such as pollution or exploitation, unable to shift their geographic range or timing of key life events, or that have narrow environmental or ecological tolerance. For example, species that must live at high altitudes or live in cold water with a narrow temperature range, such as salmon, face an even greater risk due to climate change.
“The report clearly indicates that as climate change continues to impact ecological systems, a net loss of global species’ diversity, as well as major shifts in the provision of ecosystem services, are quite likely,” said Michelle Staudinger, a lead author of the report and a USGS and University of Missouri scientist.
For example, she added, climate change is already causing shifts in the abundance and geographic range of economically important marine fish. “These changes will almost certainly continue, resulting in some local fisheries declining or disappearing while others may grow and become more valuable if fishing communities can find socially and economically viable ways to adapt to these changes.”
Natural resource managers are already contending with what climate change means for the way they approach conservation. For example, the report stated, land managers are now more focused on the connectivity of protected habitats, which can improve a species’ ability to shift its geographic range to follow optimal conditions for survival.
“The conservation community is grappling with how we manage our natural resources in the face of climate change, so that we can help our ecosystems to continue meeting the needs of both people and wildlife,” said Bruce Stein, a lead author of the report and director of climate adaptation at the National Wildlife Federation.
Other key findings of the report include:
- Changes in precipitation and extreme weather events can overwhelm the ability of natural systems to reduce or prevent harm to people from these events. For example, more frequent heavy rainfall events increase the movement of nutrients and pollutants to downstream ecosystems, likely resulting not only in ecosystem change, but also in adverse changes in the quality of drinking water and a greater risk of waterborne-disease outbreaks.
- Changes in winter have big and surprising effects on ecosystems and their services. Changes in soil freezing, snow cover and air temperature affect the ability of ecosystems to store carbon, which, in turn, influences agricultural and forest production. Seasonally snow-covered regions are especially susceptible to climate change because small precipitation or temperature shifts can cause large ecosystem changes. Longer growing seasons and warmer winters are already increasing the likelihood of pest outbreaks, leading to tree mortality and more intense, extensive fires. Decreased or unreliable snowfall for winter sports and recreation will likely cause high future economic losses.
- The ecosystem services provided by coastal habitats are especially vulnerable to sea-level rise and more severe storms. The Atlantic and Gulf of Mexico coasts are most vulnerable to the loss of coastal protection services provided by wetlands and coral reefs. Along the Pacific coast, long-term dune erosion caused by increasing wave heights is projected to cause problems for communities and for recreational beach activities. However, other kinds of recreation will probably improve due to better weather, with the net effect being that visitors and tourism dollars will shift away from some communities in favor of others.
- Climate change adaptation strategies are vital for the conservation of diverse species and effective natural resource policy and management. As moreadaptive management approaches are developed, resource managers can enhance the country’s ability to respond to the impacts of climate change through forward-looking and climate science-informed goals and actions.
- Ecological monitoring needs to be improved and better coordinated among federal and state agencies to ensure the impacts of climate change are adequately monitored and to support ecological research, management, assessment and policy. Existing tracking networks in the United States will need to improve coverage through time and in geographic area to detect and track climate-induced shifts in ecosystems and species.
From United States Geological Survey: http://www.usgs.gov/newsroom/article.asp?ID=3483
by Deep Green Resistance News Service | Dec 18, 2012 | Climate Change
By Fiona Harvey / The Guardian
Coal is likely to rival oil as the world’s biggest source of energy in the next five years, with potentially disastrous consequences for the climate, according to the world’s leading authority on energy economics.
One of the biggest factors behind the rise in coal use has been the massive increase in the use of shale gas in the US.
Coal consumption is increasing all over the world – even in countries and regions with carbon-cutting targets – except the US, where shale gas has displaced coal, shows new research from the International Energy Agency (IEA). The decline of the fuel in the US has helped to cut prices for coal globally, which has made it more attractive, even in Europe where coal use was supposed to be discouraged by the emissions trading scheme.
Maria van der Hoeven, executive director of the IEA, said: “Coal’s share of the global energy mix continues to grow each year, and if no changes are made to current policies, coal will catch oil within a decade.”
Coal is abundant and found in most regions of the world, unlike conventional oil and gas, and can be cheaply extracted. As a result, coal was used to meet nearly half of the rise in demand for energy globally in the past decade. According to the IEA, demand from China and India will drive world coal use in the coming five years, with India on course to overtake the US as the world’s second biggest consumer. China is the biggest coal importer, and Indonesia the biggest exporter, having temporarily overtaken Australia.
According to the IEA’s Medium Term Coal Market Report, published on Tuesday morning, the world will burn 1.2bn more tonnes of coal per year by 2017 compared with today – the equivalent of the current coal consumption of Russia and the US combined. Global coal consumption is forecast to reach 4.3bn tonnes of oil equivalent by 2017, while oil consumption is forecast to reach 4.4bn tonnes by the same date.
With the highest carbon emissions of any major fossil fuel, coal is a huge contributor to climate change, particularly when burned in old-fashioned, inefficient power stations. When these are not equipped with special “scrubbing” equipment to remove chemicals, coal can also produce sulphur emissions – the leading cause of acid rain – and other pollutants such as mercury and soot particles.
From The Guardian: http://www.guardian.co.uk/environment/2012/dec/18/coal-challenge-oil-international-energy-agency
