A new study shows that forests devastated by drought may lose their ability to store carbon over a much longer period than previously thought, reducing their role as a buffer between humans’ carbon emissions and a changing climate. The study shows that the world’s forests take an average of between two and four years to return to their normal growth and carbon dioxide absorption rate following a severe drought — a finding that has significant climate implications.
The iconic pine and aspen forests of the Rocky Mountains are dying off at an alarming rate thanks to conditions exacerbated by climate change — drought, insect infestations and wildfires — a new report says. Colorado alone could lose 45% of its aspen stands over the next 45 years, says the report by the Union of Concerned Scientists and the Rocky Mountain Climate Organization. Pine bark beetles alone have killed 46 million acres of trees across the west, an area nearly the size of Colorado.
An infestation of pine beetles has killed tens of thousands of acres of pines in New Jersey , and it is marching northward. Scientists say it is a striking example of the way seemingly small climatic changes are disturbing the balance of nature. They see these changes as a warning of the costly impact that is likely to come with continued high emissions of greenhouse gases.
A warming trend has contributed to a sharp rise in the number and size of wildfires on forest lands in the U.S. West, where big burns are likely to become the norm, according to a report released by a climate research group. The average annual number of fires that cover more than 1,000 acres (405 hectares) has nearly quadrupled in Arizona and Idaho and doubled in California, Colorado and six other Western states since 1970, the study by Climate Central showed. The report, which analyzed 42 years of records about fires on U.S. Forest Service lands in 11 Western states, linked rising spring and summer temperatures in the region to a fire season that begins earlier, ends later and sparks larger, more frequent blazes.
U.S. Forest Service researchers have confirmed what has long been suspected about a valuable tree in Alaska's Panhandle: climate warming is killing off yellow cedar. The mighty trees can live more than 1,000 years, resisting bugs and rot and even defending themselves against injury, but their shallow roots are vulnerable to freezing if soil is not insulated by snow. And for more than a century, with less snow on the ground, frozen roots have killed yellow cedar on nearly a half-million acres in southeast Alaska, plus another 123,000 acres in adjacent British Columbia.
The massive drought that has dried out Texas over the past year has killed as many as half a billion trees, according to new estimates from the Texas Forest Service. Between 100 million and 500 million trees were lost. That figure does not include trees killed in wildfires that have scorched an estimated 4 million acres in Texas since the beginning of 2011. A massive wildfire in Bastrop, east of Austin in September that destroyed 1,600 homes, is blamed for killing 1.5 million trees.
A huge “migration” of trees has begun across much of the West due to global warming, insect attack, diseases and fire, and many tree species are projected to decline or die out in regions where they have been present for centuries, while others move in and replace them. In a new report, scientists outline the impact that a changing climate will have on which tree species can survive, and where. The study suggests that many species that were once able to survive and thrive are losing their competitive footholds, and opportunistic newcomers will eventually push them out.
Marauding insects have become a leading threat to the nation's forests over the past decade, a problem made worse by drought and a warming climate, a federal report says. Bark beetles, engraver beetles and gypsy moths are the primary culprits behind a threefold increase in forestland mortality caused by insect attacks between 2003 and 2007, according to a U.S. Forest Service report obtained by The Associated Press. The volume of forests in the lower 48 states killed by bugs totaled 37 million acres during the period, up from 12 million during the previous five years. Millions of additional acres have perished since.
A widespread drought in the Amazon rain forest last year was worse than the "once-in-a-century" dry spell in 2005 and may have a bigger impact on global warming than the United States does in a year, British and Brazilian scientists said. More frequent severe droughts like those in 2005 and 2010 risk turning the world's largest rain forest from a sponge that absorbs carbon emissions into a source of the gases, accelerating global warming, the report found. Trees and other vegetation in the world's forests soak up heat-trapping carbon dioxide as they grow, helping cool the planet, but release it when they die and rot.
Some biologists had theorized earlier that rising greenhouse gas levels would encourage plant growth because of the increased amount of carbon dioxide in the atmosphere. But plant physiologists have shown that too much carbon dioxide actually can inhibit a plant's ability to assimilate nitrogen-based nutrients pulled from the soil that plants use to make enzymes and other essential proteins. Without those essential proteins, plant health — and food quality — may suffer.
Two years ago a vast tract of Martha’s Vineyard forest died. The 500 acres of dead oak trees were the epicenter of an islandwide infestation of caterpillars that munched their way through millions of leaves for three consecutive springs ending in 2007. Then a severe summer drought hit the island, finishing off tens of thousands of the weakened trees. Now scientists are calling it a possible climate change lesson.
The Amazon rainforest, one of the planet's most precious and besieged natural resources, is even more fragile than realized. If the planet warms even a moderate amount, a new study predicts that as much as 40 percent of it could be condemned to vanish by the end of the century.
Researchers monitoring the long-term health of the Amazon tropical rainforest have made a startling discovery. A severe drought in 2005 not only restricted the rainforest's ability to absorb carbon dioxide from the atmosphere but also, in some cases, killed off so many trees that it made areas net CO2 emitters.
The death rates of trees in western
Old-growth forests remove carbon dioxide (CO2) from the atmosphere, helping to curb the greenhouse gases that drive global warming, according to a study to be published Thursday. Many environmental policies are based on the assumption that only younger forests, mainly in the tropics, absorb significantly more CO2 than they release. As a result, primary forests in temperate and subarctic regions of the northern hemisphere do not figure in climate change negotiations seeking ways to reward countries that protect carbon-absorbing woodlands within their borders.
Warmer temperatures and longer dry spells have killed thousands of trees and shrubs in a
A beetle about the length of a well-trimmed fingernail may be challenging scientists' projections for global warming. An infestation of mountain pine beetles is turning more than 144,000 square miles of woods in
Scientists have long thought it would take generations if not centuries for tree populations to shift in response to a warming world. But scientists' work on suggests that climate change might affect
Researchers have found that wildfires fuelled by climate change may be turning boreal forests into sources of carbon dioxide. The boreal forests in northern
For many years, forestry has been an immensely profitable business in southern
Planting trees to offset carbon emissions could contribute to global warming if they are planted outside the tropics, scientists believe. While most forests do not have any overall effect on global temperature, by the end of the century forests in the mid and high latitudes could make their parts of the world more than 3C warmer than would have occurred if the trees did not exist.
While preserving and restoring forests is unquestionably good for the natural environment, new scientific studies are concluding that preservation and restoration of forests outside the tropics will do little or nothing to help slow climate change. And some projects intended to slow the heating of the planet may be accelerating it instead.
Planting forests to combat global warming may be a waste of time, especially if those trees are at high latitudes. Scientists say the benefits that come from trees reducing atmospheric carbon dioxide can be outweighed by their capacity to trap heat near the ground.
Fire-promoting droughts have become increasingly common in the Amazon, taking a terrible toll on the rain forest -- and eventually on the climate of the rest of the world.
The vast Amazon rainforest is on the brink of being turned into desert, with catastrophic consequences for the world's climate, alarming research suggests. And the process, which would be irreversible, could begin as early as next year.
A new study led by scientists at Scripps Institution of Oceanography at the University of California, San Diego, implicates rising seasonal
temperatures and the earlier arrival of spring conditions in connection with a dramatic increase of large wildfires in the western United States.
Millions of acres of Canada's lush green forests are turning red in spasms of death. A voracious beetle, whose population has exploded with the warming climate, is killing more trees than wildfires or logging. The mountain pine beetle has infested an area three times the size of Maryland, devastating swaths of lodgepole pines and reshaping the future of the forest and the communities in it.
The Amazon River basin, the world's largest rain forest, is grappling with a devastating drought that in some areas is the worst since record keeping began a century ago. It has evaporated whole lagoons and kindled forest fires, killed off fish and crops, stranded boats and the villagers who travel by them, brought disease and wreaked economic havoc.
Canadian forests are at risk from rising temperatures, according to a government agency, which warns that an increased intensity of fires and insect outbreaks could ravage the forests, affecting the forestry industry and the communities that are based in the forest.
Russia's pristine forests are the lungs of Europe. But vast swathes are being destroyed by global warming and loggers' greed - and ill-equipped firefighters are powerless to act.
The raging Western wildfires of recent years have often been blamed on management practices that promoted dense, overpacked forests. But a new study indicates global warming may be the main culprit.
The linkage suggests that as the climate warms, damaging wildfires will continue to strike the West. "If we are just at the beginning of dramatic warming & we can simply expect larger, more severe fires," said Grant A. Meyer, a co-author of the study, published in today's journal Nature.
Unusually warm temperatures have extended the life and range of bark beetles over the last several years. Trees have been weakened by several years of severe drought. All of it has led to an explosion of insect-killed trees in conifer forests. Some experts worry that the widespread damage may be part of a vast ecological shift in response to warming temperatures. "As the climate is changing, these ecosystems are rearranging themselves," said Dr. Craig Allen, a research ecologist with the United States Geological Survey in New Mexico. "Massive forest die-back is one way these systems will reassemble."
Carbon dioxide (CO2) disgorged by fossil fuels is silently causing a dramatic change in the composition of tree species in the Amazonian forest, the world's most precious wildlife haven, a study says. The CO2 is causing some tree species to grow faster and dominate in the forest and this in turn is forcing other species into decline, a long-term change which is bad news for biodiversity and the fight against global warming.
Planting trees in the Amazon to curb global warming is unlikely to work. Brazilian and US scientists have found the rainforest emits more of the greenhouse gas carbon dioxide than it absorbs when conditions are very wet. Their report, published in the journal Science, comes just three days before the latest United Nations negotiations on climate change take place in Milan. The researchers say previous studies have almost certainly over-estimated how much CO2 the Amazon can take in.
The long-standing debate about the Amazon's role in global climate change is intensifying. The Amazon is the largest tropical forest in the world -- bigger than all of Europe, with Brazil's section alone more than half the size of the continental United States. And it has always been assumed to be essential to inhibiting global warming by drawing in carbon dioxide during photosynthesis. But it has never been established whether the rain forest here is in fact functioning as a giant sink that "sequesters," or traps and absorbs, carbon.
A new experiment has shown that fairly common concentrations of low-level ozone, the eye-stinging ingredient in smog, can sharply impede the ability of trees to absorb heat-trapping carbon dioxide.
Mature trees might not offset global warming by mopping up excess carbon dioxide, suggests a forest study in Switzerland. They may already have all the carbon dioxide that they need. If the phenomenon is widespread, it could be a setback to those hoping that existing and newly planted forests will buffer mounting CO2 levels.
It was a comforting dream while it lasted: Carbon dioxide spewed into the air from tailpipes and smokestacks would speed up the growth of forests. The forests in turn would store the carbon in wood and soil, staving off climate change. But the latest research has delivered an unpleasant wake-up call.
New research has shown that the forest fires which ravaged South East Asia five years ago caused a massive increase in levels of the greenhouse gases which cause global warming. Scientists from Indonesia and Europe believe that 2.6 million tons of carbon entered the atmosphere after the fires in Indonesia - contributing to the biggest annual increase in carbon emissions since records began. The world generates annually about 7 billion tons of carbon emissions.
While forest fires in the West have captured the nation's attention, a similar but less visible disaster has been wreaking havoc with East Coast trees: an arboreal broil caused by this summer's record-breaking drought and high temperatures. From Georgia to New Jersey, extreme water shortages and heat waves have placed even drought-resistant trees under severe stress, causing early leaf loss, increased susceptibility to disease and premature death.
Human activities are changing the global climate, and these changes are having far reaching effects on tropical forests. University of Missouri scientist Deborah Clark re-evaluated the evidence and told the symposium that tropical forests may not be carbon sinks that can be used to absorb carbon dioxide generated by the burning of fossil fuels. Instead, tropical forest may end up contributing even more carbon dioxide (CO2) to the atmosphere as temperature rises, she said.
Nearly four million acres of white spruce trees, dead or dying from an infestation of beetles in Alaska's Kenai Peninsula, the largest kill by insects of any forest in North America. A succession of warm years in Alaska has allowed spruce bark beetles to reproduce at twice their normal rate.
After a mild winter, the sandgrain-sized Asian woolly adelgid, usually killed by the cold, is thriving and expected to burst into dozens more Massachusetts communities, some as soon as this summer. And hemlocks, weakened by one of the worst droughts on record, are not expected to withstand the infestation for long.
Two new studies are challenging the idea that planting forests could be a cheap way to absorb emissions of carbon dioxide, the main heat- trapping gas released by human activities.In one, tracts of pine trees exposed to elevated levels of the gas initially absorbed large amounts and had a short growth spurt, but then reverted to typical growth rates. A separate study of the soil around the exposed trees found that decomposition released much of the carbon that had been absorbed.
New research has found that the massive amounts of atmospheric carbon dioxide generated by fossil fuel use in the U.S. are not offset by the storage of carbon in growing forests and other vegetation, as some earlier studies had suggested. The new study, has important implications for the role of the U.S. in combating the greenhouse effect and global warming.