tagged w/ Carbon sinks
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Karina Pinasco watched in dismay as flames on a hillside at the edge of town lit up the sky one night in October 2010. A farmer had intended to clear a few hectares of land to plant coffee bushes, but the fire – set during an unusually hot, dry spell – quickly got out of hand.
Propelled by winds and high temperatures, it burned for 10 days, charring more than 250 acres of land.
"We realized we weren't prepared," says Pinasco, a biologist who heads Amazónicos por la Amazonía, a local environmental organization. "The firefighters weren't trained. It was the rain that finally put it out."
Scientists used to think the rainforest, especially in the western Amazon, was too wet to burn. But major fire seasons in 2005 and 2010 made them reconsider.
Fires are a major source of carbon emissions in the Amazon, and scientists are beginning to worry that the region could become a net emitter, instead of a carbon sink. New findings link rising ocean temperatures off the northern coast of Brazil to changing weather patterns: As the Atlantic warms, it draws moisture away from the forest, priming the region for bigger fires.
"We are reaching a tipping point in terms of drought, beyond which these forests can catch fire," says Daniel Nepstad, international program director at the Amazon Environmental Research Institute in Brasília, Brazil.
Once-a-century no more
The 2005 drought – considered a once-in-a-century event – resulted in unprecedented wildfires in Acre, the western Brazilian state bordering Peru. Flames scorched the tree canopy, and at one point the front face of the fire stretched nearly seven miles. As many as 1.2 million acres of forests were affected in Acre and the neighboring regions of Pando in Bolivia and Madre de Dios in Peru. Officials estimated upwards of $100 million in economic damages.
But the forest loss wasn't the only concern for the Acre state government, said Foster Brown, a senior scientist at the Woods Hole Research Center and a professor at the Federal University of Acre in Rio Branco, the state capital. Choking smoke spiked respiratory ailments in the region and canceled flights.
Just five years later, another once-a-century drought struck, and fires spread out of control, especially in Acre, Bolivia's Pando region and Brazil's Mato Grosso state. Acre was better prepared, but in Bolivia, smoke from more than 20,000 fires reduced visibility and shut airports in several towns. The Bolivian government declared a state of emergency as more than 3.5 million acres of forest burned. In Mato Grosso, fires destroyed at least 100 homes.
Gigatons of carbon
The 2005 fires added 1.6 gigatons of carbon to the atmosphere, according to a study by Simon Lewis of the University of Leeds, who put emissions from the more widespread 2010 fires at 2.2 gigatons.
In a normal year, the Amazon forests store 0.4 gigatons of carbon a year in the trees and soil, meaning that two bad seasons like 2005 and 2010 could wipe out a decade of gain, according to Lewis' calculations.
And as humans push further into an increasingly drier Amazon, the problem could worsen.
In the western Amazon, humans are the chief source of sparks. With new roads being built and paved through once-inaccessible areas, Peru's Amazonian regions now have some of the country's highest population growth rates. Many of the newcomers clear a little land to farm, and where there are farms, there is fire.
Fire risks
In the Amazon, where weeds and insects run rampant, burning is the most cost-effective way for small farmers to control ticks in cattle pastures and unwanted plants in cassava fields, says Miguel Pinedo-Vásquez, director of international programs for the Columbia University Center for Environmental Research and Conservation, who also works with the Center for International Forestry Research.
More at the linkKarina Pinasco watched in dismay as flames on a hillside at the edge of town lit up... more
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Man-made carbon emissions have acidified the world's oceans far beyond their natural levels, new research suggests.
In some regions, acidity levels rose faster in the last two centuries than it did in the previous 21,000 years, a study from the University of Hawaii has shown. Ocean acidity makes it harder for organisms such as molluscs and coral to construct the protective layers they need to survive.
Measuring changes in ocean acidity is difficult because it varies naturally between seasons, years and regions. Scientists looked at changes in the saturation level of aragonite, a form of calcium carbonate used to measure ocean acidification.
As seawater acidity rises, the saturation level of aragonite falls. Direct observations only date back 30 years, which is not long enough to reveal a meaningful trend. However the new research used simulations of ocean and climate conditions going back 21,000 years to the Last Glacial Maximum and forward in time to the end of the 21st century.
In several key coral reef regions aragonite saturation is already five times below its lowest pre-industrial range, according to the model. This translates to a decrease in overall calcification rates of corals and other shell-forming organisms of 15%, scientists at the university believe.
They fear calcification rates of some marine organisms could drop by more than 40% of their pre-industrial levels within the next 90 years.
Dr Tobias Friedrich, from the University of Hawaii, who led the study published in the journal Nature Climate Change, said: 'Any significant drop below the minimum level of aragonite to which the organisms have been exposed to for thousands of years and have successfully adapted will very likely stress them and their associated ecosystems.
'In some regions, the man-made rate of change in ocean acidity since the industrial revolution is 100 times greater than the natural rate of change between the Last Glacial Maximum and pre-industrial times.'
He added: 'When Earth started to warm 17,000 years ago, terminating the last glacial period, atmospheric CO2 (carbon dioxide) levels rose from 190 parts per million (ppm) to 280 ppm over 6,000 years.
'Marine ecosystems had ample time to adjust. Now, for a similar rise in CO2 concentration to the present level of 392 ppm, the adjustment time is reduced to only 100 - 200 years.'
Co-author Professor Axel Timmermann, also from the University of Hawaii, said: 'Our results suggest that severe reductions are likely to occur in coral reef diversity, structural complexity and resilience by the middle of this century.'
Read more: http://www.dailymail.co.uk/sciencetech/article-2090253/Oceans-acidified-200-years-did-previous-21-000-years-claims-new-climate-change-research.html#ixzz1kJIObunQMan-made carbon emissions have acidified the world's oceans far beyond their... more
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CO2 is termed the Earth's biggest control knob. It hadn't been until now, because a knob implies something that someone can turn to control things. In a normal, natural world and on relatively short timescales, say tens of thousands of years, carbon dioxide is interlocked with global mean temperature and other variables. Temperatures can drive carbon dioxide levels up or down, which in turn drive temperatures further up or down.
Carbon dioxide acts as a feedback that enhances temperature changes.
This is most obvious during the transitions between glacial and interglacial periods, when temperatures rise or drop and CO2 seems to follow along like a happy puppy. What is not obvious when looking at the readings is that while orbital forcings cause the initial change in temperatures, and CO2 levels rise or fall in accordance with that initial change, the subsequent temperatures themselves also rise and fall in accordance with the changing CO2 levels.
The basic formula behind a glacial termination is that something (orbital forcings) starts the increase in temperature. Actually, what really starts it is a change in the length and severity of northern hemisphere summers, without changing the overall amount of radiation reaching the planet at all. That stays fairly constant.
These seasonal changes in turn cause the ice sheets covering the northern hemisphere land masses to begin to melt. This reflects less sunlight back into space, and that really does change the amount of energy that the planet receives from the sun, which leads to warming. It also results in the release of methane, another powerful greenhouse gas, which warms the planet even further.
Then CO2 kicks in. The oceans warm. Warmer water cannot hold as much dissolved carbon dioxide and so the oceans release some CO2 into the atmosphere. CO2 in the atmosphere causes warming. The increased warming causes the ice sheets to retreat further, and the oceans to warm further, and more CO2 to be released.
This continues, but with limits. There is (or had been) only so much CO2 that could make its way into the atmosphere. The system only pushes this cycle so far. The many previous glacial terminations in the past 2.5 million years (a period known as the Pleistocene Epoch) have seen lows of about 180 ppm of CO2, and highs between 250 ppm and 300 ppm.
The main point is that temperatures and CO2 are interlocked, or at least had been until now. Temperature changes had to get the ball rolling, so on a graph they will lead the way, but the two work in concert. One is not pulling a leash to drag the other along. They each push and pull the other, working their way from low to high, or high to low, as an integrated system.
CO2 does not "lag" temperature. That's a simplistic, inaccurate and indiscriminate view of a complex interaction.
Turning the Knob
Unfortunately, contrary to recent natural history, man has learned how to remove the regulator and to dial up a far higher level of CO2 in the atmosphere. CO2 has become the climate's biggest control knob in the last two centuries or so, in the sense that it is in fact a control that mankind can twist, turn, tweak and, sadly, overdo.
A glacial termination happens on very, very long timescales relative to man. What we have done in the past two centuries, however, applies a change to CO2 levels — implying an equivalent change in climate — that would otherwise take nature 10 to 12 thousand years.
CO2 was once interlocked with temperature. In the past 200 years we have instead taken 337 gigatonnes of carbon out of the ground and injected it into the atmosphere and the oceans. Nature spent the better part of several hundred million years converting that carbon into new forms (coal, oil, gas) and sequestering it deep under the surface of the earth.
Man will be able to undo in 200 years what took nature hundreds of millions of years to accomplish, and in so doing, in that same time frame, we are duplicating a feat that normally takes nature 10,000 years to accomplish (i.e. increasing atmospheric CO2 levels by two thirds).
And, as an important point, we have no idea if we are capable of duplicating nature's feat of again sequestering that carbon underground. We have far too easily turned the knob in one direction, but with no capacity whatsoever to turn it in the other.
More at the linkCO2 is termed the Earth's biggest control knob. It hadn't been until now,... more
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In July I attended a public debate in London on the potential for REDD (Reducing Emissions from Deforestation and Forest Degradation) to make international forestry more just. The debate brought together a wide variety of stakeholders in REDD in order to assess its possibilities and its frailties. The panel leading the discussion included John Vidal from the Guardian and representatives from DFID, ODI, and FERN among others. What became increasingly clear during the debate is that although the international community appeared to be pushing on with REDD, it remains a highly contested and confused idea.
For those still unsure of what the initiative is, REDD is an effort to create a financial value for the carbon stored in forests. It offers incentives for developing countries to reduce emissions from forested lands and invest in low-carbon paths to sustainable development. However, the discussion highlighted fears that REDD may perpetuate, or even deepen, forest people’s historical dispossession from their forests.
The discussion focused on the concept of justice within REDD and the focal point of the evening turned out to be “local justice”. The question was - what is happening to the local people on the ground where these initiatives are implemented? It became increasingly clear, by hearing arguments from members of FERN and from those on the ground, that it is forest people that often are the ones who are most negatively affected by these projects. There is an overriding fear that REDD may not be dissimilar to other big money projects affecting the forests. For instance, a member of the audience, who had worked on a REDD project in Peru, stated that it was seen as more dangerous than palm oil plantations. The fear is that these projects can potentially, and almost by nature, take over entire forests, leaving indigenous people to lose the land earmarked for these REDD projects.
During the evening, several other members of the audience stated it was governments, and not large corporations, who were taking control of the forests. The ODI representative feared that REDD projects will reaffirm the ownership of the forests by the state. For example, as the government controls the carbon it trades, the forests fall under their control. This will go on to reinforce highly centralized, top down decision-making, something GBM works to move away from.
The panel was in agreement about what must be done, forest peoples and local communities must be included and able to make decisions for the future of forests in all REDD projects. Increasing evidence from Brazil and elsewhere indicates that tenure reform, that is placing control of forest resources into the hands of indigenous and other forest-dependent communities, contributes to local well-being and forest protection.
More at the linkIn July I attended a public debate in London on the potential for REDD (Reducing... more
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Time to get louder at government about this. Time to win this conversation with truth. CO2 traps heat. One of the main points of this, plus some others I divulge. ;l). Thanks Current for this venue for us to tell it like it is.
This video is dedicated to the indigenous peoples of our world and those experiencing the brunt of the effects of climate change/biodistress. May we find it within us to do what is right for all.Time to get louder at government about this. Time to win this conversation with truth.... more
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How important are forests to our survival? Like our oceans we cannot live without them. However, we are cutting them down faster than we are replenishing them which does not bode well for the health of our environment, climate and biodiversity. But you can make a difference.
Please feel free to add anything about forests or organizations you know of making a difference. We have many trees to plant to make up even partly for the damage we have caused. Let's get started!How important are forests to our survival? Like our oceans we cannot live without... more
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The oil spill in the Gulf of Mexico is a disaster, but it may pale compared to what scientists say is brewing in the world's oceans due to everyday consumption of fossil fuels.
The billions of tonnes of carbon dioxide sent wafting into the atmosphere each year through the burning of oil, gas and coal are profoundly affecting the oceans, says a series of reports published Friday in the journal Science.
One says there is mounting evidence that "rapidly rising greenhouse gas concentrations are driving ocean systems toward conditions not seen for millions of years, with an associated risk of fundamental and irreversible ecological transformation."
Another says that the effects are already rippling through the food web in Antarctica.
And a third says humans, and their ever-increasing carbon emissions, are acidifying the ocean in a "grand planetary experiment" that could have devastating impacts.
Marine scientists Ove Hoegh-Guldberg, at the University of Queensland in Australia, and John Bruno, at University of North Carolina, describe how the oceans act as a "heat sink" and are slowly heating up along with the atmosphere as greenhouse gas emissions climb.
The warming, they say, is "likely to have profound influences on the strength, direction and behaviour" of major ocean currents and far-reaching impacts on sea life.
The oceans also soak up close to a third of the carbon dioxide that humans put into the atmosphere and it reacts with sea water to form acidic ions. The rising acidity "represents a major departure from the geochemical conditions that have prevailed in the global ocean for hundreds of thousands, if not million of years," the scientists report.
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"The impacts of anthropogenic (human) climate change so far include decreased ocean productivity, altered food web dynamics, reduced abundance of habitat-forming species, shifting species distributions and a greater incidence of disease," they say.
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A news report, accompanying the Science papers on the oceans, says by increasing the ocean's acidity "humans are caught up in a grand planetary experiment" that could take a "potentially devastating toll on marine life." The rising acidity could erode the calcium carbonate shells and skeletons of corals, mollusks and some algae and plankton — and there is some evidence it is already starting to occur.
Read more: http://www.ottawacitizen.com/technology/Carbon%20emissions%20having%20harmful%20lasting%20impact%20oceans%20Reports/3166754/story.html#ixzz0rYITQnUEThe oil spill in the Gulf of Mexico is a disaster, but it may pale compared to what... more
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Military chiefs are holding discussions on how to cope with the threat of a world ravaged by wars provoked by uncontrolled climate change.Military chiefs are holding discussions on how to cope with the threat of a world... more
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The increasing acidity of the world's oceans - and that acidity's growing threat to marine species - are definitive proof that the atmospheric carbon dioxide that is causing climate change is also negatively affecting the marine environment, says world-renowned Antarctic marine biologist Jim McClintock, Ph.D., professor in the University of Alabama at Birmingham (UAB) Department of Biology.
"The oceans are a sink for the carbon dioxide that is released into the atmosphere," says McClintock, who has spent more than two decades researching the marine species off the coast of Antarctica. Carbon dioxide is absorbed by oceans, and through a chemical process hydrogen ions are released to make seawater more acidic.
"Existing data points to consistently increasing oceanic acidity, and that is a direct result of increasing carbon dioxide levels in the atmosphere; it is incontrovertible," McClintock says. "The ramifications for many of the organisms that call the water home are profound."
A substance's level of acidity is measured by its pH value; the lower the pH value, the more acidic is the substance. McClintock says data collected since the pre-industrial age indicates the mean surface pH of the oceans has declined from 8.2 to 8.1 units with another 0.4 unit decline possible by century's end. A single whole pH unit drop would make ocean waters 10 times more acidic, which could rob many marine organisms of their ability to produce protective shells - and tip the balance of marine food chains.
"There is no existing data that I am aware of that can be used to debate the trend of increasing ocean acidification," he says.
McClintock and three co-authors collected and reviewed the most recent data on ocean acidification at high latitudes for an article in the December 2009 issue of Oceanography magazine, a special issue that focuses on ocean acidification worldwide. McClintock also recently published research that revealed barnacles grown under acidified seawater conditions produce weaker adult shells.
Antarctica as the Ground Zero for Climate Change
McClintock says the delicate balance of life in the waters that surround the frozen continent of Antarctica is especially susceptible to the effects of acidification. The impact on the marine life in that region will serve as a bellwether for global climate-change effects, he says.
"The Southern Ocean is a major global sink for carbon dioxide. Moreover, there are a number of unique factors that threaten to reduce the availability of abundant minerals dissolved in polar seawater that are used by marine invertebrates to make their protective shells," McClintock says.
"In addition, the increased acidity of the seawater itself can literally begin to eat away at the outer surfaces of shells of existing clams, snails and other calcified organisms, which could cause species to die outright or become vulnerable to new predators."
One study McClintock recently conducted with a team of UAB researchers revealed that the shells of post-mortem Antarctic marine invertebrates evidenced erosion and significant loss of mass within only five weeks under simulated acidic conditions.
McClintock says acidification also could exert a toll on the world's fisheries, including mollusks and crustaceans. He adds that the potential loss of such marine populations could greatly alter the oceans' long-standing food chains and produce negative ripple effects on human industries or food supplies over time.
"So many fundamental biological processes can be influenced by ocean acidification, and the change in the oceans' makeup in regions such as Antarctica are projected to occur over a time period measured in decades," McClintock says.
contThe increasing acidity of the world's oceans - and that acidity's growing... more
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Contradicting the belief that trees will absorb more carbon dioxide as the world warms, a new study says that sub-Alpine forests in the western United States are likely to soak up less CO2 as temperatures rise and snowpack declines. Researchers at the University of Colorado found that while reduced snowpack generally advanced the onset of spring and extended the growing season, the decline in snow slashed the amount of water available to trees in summer and fall, causing them to less efficiently convert carbon dioxide into biomass. The researchers said that snow was much more effective at delivering moisture to trees than rain, and that as late as October, 60 percent of the water in the stems and needles of sub-Alpine trees can be traced back to snowmelt. That means that even if rainfall increases, the ability of sub-Alpine trees to absorb CO2 will decline if snowpack in the Rocky Mountains declines. “As snowmelt in these high-elevation forests is predicted to decline, the rate of carbon uptake will likely follow suit,” said researcher Jia Hu, whose study will be published next month in the journal Global Change Biology. Sub-Alpine forests account for roughly 70 percent of carbon storage in the western United States.Contradicting the belief that trees will absorb more carbon dioxide as the world... more
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25-40% below 1990 levels is what is stated by scientists as the target to avoid a 2 degree rise in temperature that is considered the threshhold for a tipping point. We could do that by employing reforestation and sustainable agricultural methods alone which would also preserve soil carbon and nutrients and preserve biodiversity. And direct pricing of carbon on an industrial level would spur investment in renewable energies with rebates to consumers. It is simply common sense to work to preserve our climate balance not only for health reasons, but economic and social reasons as well. We can no longer afford to do nothing, or next to nothing.25-40% below 1990 levels is what is stated by scientists as the target to avoid a 2... more
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A new study has come out which has found that humanity would need the equivalent of five planet Earths to produce the resources needed if everyone consumed as much as Americans.A new study has come out which has found that humanity would need the equivalent of... more
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Leading scientists said this week that the world is now firmly on course for the worst-case scenario in terms of climate change, with average global temperatures rising by up to 6°C by the end of the century. Such a rise would have cataclysmic and irreversible consequences for the Earth, making large parts of the planet uninhabitable and threatening the basis of human civilization itself.Leading scientists said this week that the world is now firmly on course for the... more
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WWF Sweden is urging its government — holding the current EU Presidency - to get behind an effective international agreement on halting forest loss as a key and highly cost effective measure on climate change.
"Sweden should follow the examples set by its northern neighbors in developing systems to halt deforestation," said WWF CEO General Lasse Gustavsson.. "One Swedish krona to stem deforestation results in the same emissions reductions as five kronor for the controversial carbon capture and storage technique."
Gold in Green Forests, a report issued today by WWF-Sweden, says that next to energy efficiency halting forest loss and degradation is the most cost-effective method for mitigating climate change.
The annual loss of natural forests in developing countries is equivalent to one third of Sweden’s surface area. Forest fires, the conversion of forests to agricultural land and the cultivation of energy crops are responsible for the high rate of forest loss.
A program to reduce greenhouse gas emissions from deforestation, known as REDD (Reducing Emissions from Deforestation and Forest Degradation) is currently being discussed in the negotiations for a global climate deal. REDD aims to make it worthwhile for developing countries to maintain their forests, as opposed to cutting them down.
Article continues:
http://www.panda.org/wwf_news/news/?uNewsID=176141WWF Sweden is urging its government — holding the current EU Presidency - to get... more
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Our forests and our agriculture will save us.
Excerpt:
South Asian countries must be rewarded for afforestation, reforestation and carbon stock growth, say N. H. Ravindranath and Shamama Afreen.
In December 2007, at the UN Framework Convention on Climate Change (UNFCCC) conference in Bali, Indonesia, governments from developed and developing countries alike adopted a 'roadmap' for stepping up efforts to combat climate change.
The roadmap included,among other measures,a commitment to establish policy approaches and incentives for reducing emissions from deforestation and forest degradation (REDD). These are due to be agreed at the UNFCCC climate negotiations in Copenhagen later this year.
Strategies for REDD have been much debated and some developing countries clearly stand to benefit from the proposals. But others, particularly those with low forest cover and low deforestation rates, have little to gain unless negotiators also consider the role of conservation and sustainable forest management.
REDD winners
According to the Intergovernmental Panel on Climate Change (IPCC), the forestry sector contributes about 17 per cent of global greenhouse emissions, making it the second largest source next to energy supply. Estimates put emissions from deforestation in the 1990s at 5.8 gigatonnes of carbon dioxide a year. Deforestation is certainly the largest source of emissions for many developing countries. Research estimates that 12.9 million hectares of tropical forest were lost each year from 2000–2005, mainly through conversion to agricultural land, but also due to expanding settlements and infrastructure.
Brazil, Indonesia, Myanmar, the Democratic Republic of Congo and Zambia occupied the top five positions from 1990–2005, annually deforesting anything from nearly half a million hectares in Zambia to nearly three million hectares in Brazil. And unless action is taken, deforestation is likely to remain high in the tropics over the coming years and decades.
So reducing tropical deforestation is seen as a high-priority way of mitigating potential climate change. And in its 2007 Fourth Assessment Report, the IPCC concluded that it would not cost much to do.
The UNFCCC's vision for REDD is to give developing countries financial incentives to reduce national deforestation rates and associated carbon emissions below a baseline (based either on a historical reference case or future projection). By doing so, REDD should contribute to climate change mitigation and adaptation.Our forests and our agriculture will save us.
Excerpt:
South Asian countries... more
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The conflict between conserving environments and improving livelihoods is constricting efforts for reducing emissions from deforestation and forest degradation (REDD) in Sub-Saharan Africa. But agroforestry — managing trees with agricultural production — could help.
The Financial Times calls the carbon market the world's fastest growing commodity market — with agriculture, forestry and other land use playing an increasingly important role. The idea behind REDD is simple — pay countries to reduce carbon emissions from deforestation and degraded lands.
But working out practical solutions that meet key Millennium Development Goals — namely, to end extreme poverty and hunger, and ensure environmental sustainability — remains difficult.
More trees, better livelihoods
Developing countries' quest for food security through agricultural expansion often leads to deforestation and forest degradation. The main challenge for much of Sub-Saharan Africa is how to design agricultural landscapes to resolve livelihood-environment conflict and maintain forests' ecosystem benefits such as water storage, erosion control, biodiversity conservation and soil rehabilitation.
The way forward is to integrate climate and livelihood, adaptation and mitigation, REDD and agriculture. Agroforestry should be a key component of this approach. Integrating trees into agricultural landscapes on a massive scale would create an effective carbon sink while ensuring sustainable food production, and would help adapt to climate change in other ways too.
Tree-based systems are much better at accumulating carbon, above and below ground, than pure agriculture. A 'green investment' project in India has demonstrated how to harness tree planting for carbon off-setting (see Growing money on trees?). Tree and carbon experts from the World Agroforestry Centre suggest that a billion hectares of farmland (much of it in developing countries) could be turned into carbon-rich agricultural landscapes, potentially sequestering 50 billion tonnes of carbon dioxide — a third of the carbon reduction challenge.
Of course, saving carbon is not usually the top priority for small-holder farmers— but agroforestry can contribute many of the other benefits farmers want too. For example, a meta-analysis of 94 scientific publications — conducted by World Agroforestry Centre researchers and published in Plant and Soil in 2008 — indicates that using 'fertiliser trees' that capture nitrogen from the air and transfer it to the soil can reduce the need for commercial nitrogen fertilisers by 75 per cent while doubling crop yields. If combined with other soil fertility management, such as conservation agriculture, fertiliser trees can significantly boost sustainable soil health and increase food security. A diverse tree cover can also increase agroecosystems' resilience towards drought, pest and disease and other threats on food production induced by climate change.
more at the link.The conflict between conserving environments and improving livelihoods is constricting... more
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The oldest and largest trees within California's world famous Yosemite National Park are disappearing.
Climate change appears to be a major cause of the loss.
The revelation comes from an analysis of data collected over 60 years by forest ecologists.
They say one worrying aspect of the decline is that it is happening within one of most protected forests within the US, suggesting that even more large trees may be dying off elsewhere.
James Lutz and Jerry Franklin of the University of Washington, Seattle, US and Jan van Wagtendonk of the Yosemite Field Station of the US Geological Survey, based in El Portal, California collated data on tree growth within the park gathered from the 1930s onwards.
Their key finding is that the density of large diameter trees has fallen by 24% between the 1930s and 1990s, within all types of forest.
"These large, old trees have lived centuries and experienced many dry and wet periods," says Lutz. "So it is quite a surprise that recent conditions are such that these long-term survivors have been affected."
The wider the diameter, the more aged the tree (J. A. Lutz).
Large trees are not only older, but they play a distinct and important role within forest ecosystems.
Their canopies help moderate the local forest environment while their understory creates a unique habitat for other plants and animals.
Older, larger trees also tend to seed the surrounding area and crucially are able to withstand fires, short term climatic changes and outbreaks of insect pests that can kill or weaken smaller trees.
But the study by Lutz's team suggests they are no longer faring well.
In a study published in Forest Ecology and Management, the researchers collated all the data that existed on tree growth with the Yosemite National Park. In particular, this included two comprehensive surveys: one conducted in the mid 1930s and another during the 1990s.
"Few studies like this exist elsewhere in the world because of a lack of good measurements from the early 20th Century," says Lutz.
Including 21 species of tree recorded by both surveys, the density of large diameter trees fell from 45 trees per hectare to 34 trees, a decline of 24% in just over 60 years. White Firs (Abies concolor), Lodgepole Pines (Pinus contorta) and Jeffrey Pines (Pinus jeffreyi) were affected the most. Smaller size trees were unaffected.
Trees of this diameter are becoming more scarce (A. J. Larson).
"One of the most shocking aspects of these findings is that they apply to Yosemite National Park," says Lutz. "Yosemite is one of the most protected places in the US. If the declines are occurring here, the situation is unlikely to be better in less protected forests."The oldest and largest trees within California's world famous Yosemite National... more
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North America's primary forests have a big role in preventing climate change. They need our protection.-------------------------------
OK, already. You're changing light bulbs, sealing up leaks in the attic, looking for a smaller car and trying to drive less. By now, most of us are familiar with the urgent need to take every possible action to burn less oil, use less energy and reduce global warming. But, then there are the forests. What are you doing about the forests?
Forests are a big part of the climate equation. Deforestation produces about 20% of total global greenhouse gas emissions. Industrial disturbances in forests exacerbate global warming. The more the forest is disturbed, the more carbon is released. Fortunately, North Americans have an outstanding opportunity to aid climate stewardship just by managing and protecting our forests.
This complex issue was incompletely addressed under the Kyoto Protocol. Rules for forest emissions and incentives to reduce them are still being negotiated. Forests and climate change are also an ongoing focus for scientists advising the United Nations.
To date, the spotlight has largely been on tropical forests. But northern forests need to be part of the discussion. Findings recently presented at the UN Forum of Forests demonstrate that protecting remaining primary forests in both the north and the tropics is an effective tool in preventing emissions that would otherwise accelerate climatic disruption. North America's forests have a big role in that global equation.
The circumpolar Boreal Forest, including vast swaths of northern Canada and Alaska, is the world's largest forested region. This forest stores more carbon per acre than any other ecosystem, making it the world's largest terrestrial carbon storehouse. Also important is the complex of coniferous forests in the mountains of lower latitudes, especially in the United States.
In the US, much of the coniferous forest is in public ownership and could be set aside, protected immediately in the public interest, by governmental policy. It should be. This would immediately signify to the world that the nation is serious in its approach to the climatic disruption.
In Canada, with its vast Boreal Forest carbon storehouse, the potential is even greater. Rivalling the Amazon Rainforest in size, the Boreal Forest also provides globally-important, irreplaceable reserves of fresh water and habitat for enormous, healthy populations of wildlife, including millions of migratory caribou and billions of migratory birds.
Over 1,500 international scientists, led by Nobel prize-winning authors for the International Panel on Climate Change, have recommended that at least half of Canada's Boreal Forest be protected from any further disturbance.
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I didn't read all 900 plus pages of the ACES bill, but I didn't notice in my reading about it that deforestation in North America, particularly the United States was being addressed in the equation to sequester carbon and that is a big mistake. Just by caring for and reforesting our forests we would sequester enough carbon to go way beyond the 17% by 2020 guideline set by that bill that is way below scientist's recommendations. However, to set aside these public lands to allow the people of America to take part in the solution to this crisis doesn't make $$$$$$$ for those special interests and industries looking to make a pile of money off of this bill. Our forests in America and primarily the Boreal Forest of Alberta that has been ravaged by tarsands needs to be reforested, protected, and cared for. Trees are the natural answer to this crisis. The fact that this Congress will not even address that in a climate bill that is being touted as "historic" only speaks to me of the true motivations behind it. It may sound simple, and it may sound trite, but we need to Plant America.
http://plantamerica.blogspot.comNorth America's primary forests have a big role in preventing climate change.... more
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Drought in the Amazon is imperiling the rainforest ecosystem and global climate, reports new research published in Science.
Analyzing the impact of the severe Amazon drought of 2005, a team of 68 researchers across 13 countries and 40 institutions found evidence that rainfall-starved tropical forests lose massive amounts of carbon due to reduced plant growth and dying trees. The 2005 drought — triggered by warming in the tropical North Atlantic rather than el Niño — resulted in a net flux of 5 billion tons of carbon dioxide (CO2) into the atmosphere — more than the combined annual emissions of Japan and Europe — relative to normal years when the Amazon is a net sink for 2 billion tons of CO2.
The findings suggest that in the face of warming climate, relying on tropical forests as a massive carbon sink is a perilous proposition, raising questions about the effectiveness of schemes to offset industrial emissions by protecting rainforests without also curbing fossil fuel use. Should droughts worsen on a global scale, forests could become a net source of emissions, exacerbating climate change.
"For years the Amazon forest has been helping to slow down climate change. But relying on this subsidy from nature is extremely dangerous", said lead author Oliver Phillips, referencing newly published research indicating that tropical forests have absorbed as much as a fifth of fossil fuel emissions in recent decades.
"If the earth's carbon sinks slow or go into reverse, as our results show is possible, carbon dioxide levels will rise even faster," Phillips, a professor at the University of Leeds, added. "Deeper cuts in emissions will be required to stabilize our climate."
The researchers estimate that old growth forests in the Amazon store roughly 120 billion tons of carbon in their vegetation and process — through photosynthesis and respiration — 18 billion tons of carbon annually, or more than twice the emissions from fossil fuel use. Given this massive scale of carbon cycling, "relatively small changes in Amazon forest dynamics therefore have the potential to substantially affect the concentration of atmospheric CO2 and thus the rate of climate change itself," they note.
Overall the study found that a 100-millimeter (4 inch) increase in water deficit triggers the loss of 2.7 tons of aboveground forest carbon per hectare. However the impact of drought may be even worse — dry conditions greatly increase the risk of forest fire, including small surface fires that can inflict serious harm in even old-growth rainforest.
Drought also affects the species composition of the forest. Some species, especially fast-growing, light-wooded trees, are particularly vulnerable to reduced rainfall.
"Amazon drought kills selectively and therefore may also alter species composition, pointing to potential consequences of future drought events on the biodiversity in the Amazon region," the authors write.
"Drought threatens biodiversity too," said co-author Abel Monteagudo, a Peruvian botanist with the Missouri Botanical Gardens.
Unlikely other research that has relied primarily on satellite imagery to measure drought stress (including one that suggested dry conditions enhance growth in the Amazon), the study was conducted under RAINFOR, a research network that monitors death rates and growth among more than 100,000 trees in 100 forest plots across the Amazon's 600 million hectares. The granularity of the study allowed scientists to directly measure changes that would not be otherwise readily apparent but may have big impacts.Drought in the Amazon is imperiling the rainforest ecosystem and global climate,... more
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An effort to fight climate change through reforestation, seeded at the grassroots level, has now blossomed into a woodland of over 3 billion trees, with the confirmation that over 300 million were planted in Turkey in 2008, the United Nations announced today.
In response to its success, the Billion Tree Campaign, which is under the patronage of Nobel Peace Prize Laureate and Kenyan Green Belt Movement founder Professor Wangari Maathai and Prince Albert II of Monaco, has already set a new target of 7 billion trees to be planted by the UN Climate Change Conference to be held in December 2009.
The campaign was launched by the UN Environment Programme (UNEP) and the World Agroforestry Centre (ICRAF) in 2006 as a response not only to the threat of global warming but also to wide sustainability challenges from water supplies to biodiversity loss.
Tree planting remains one of the most cost-effective ways to address climate change, according to UNEP. Trees and forests play a vital role in regulating the climate since they absorb carbon dioxide. Deforestation, in turn, accounts for over 20 per cent of the carbon dioxide humans generate, rivalling the emissions from other sources.
Trees also play a crucial role in providing a range of products and services to rural and urban populations, including food, timber, fibre, medicines and energy as well as soil fertility, water and biodiversity conservation.
With slightly over 700 million trees planted to date, Turkey now attains second position in the list of top 10 countries in the Campaign's roll of honour. The leading country remains Ethiopia with 725 million trees planted, UNEP said. Mexico, with 472,404,266 trees planted to date, Kenya with 139,893,668 and Cuba with 137,476,771 round out the top five in the sylvan effort.
Meanwhile, an organization in Romania known as the PRAIS Foundation, in partnership with the Romanian Government and other partners, has confirmed that it has planted over 11 million trees through the national tree-planting movement 'Millions of People, Millions of Trees.'
In total, 3,071,704,993 trees have been planted around the world. So far, another 1,578,796,459 trees have been pledged and have yet to be planted.An effort to fight climate change through reforestation, seeded at the grassroots... more
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