Posted on March 22, 2015 by Bob Berwyn
‘As a wealthy country, Australia has the capability and responsibility to improve its management of the reef’
FRISCO — Strong local management may be the key to preserving treasured world heritage sites, researchers concluded in a new study after taking a close look at threats facing the Amazon Rainforest, the Great Barrier Reef and Spain’s Doñana wetlands.
The team of scientists, who published their findings in the journal Science, said protecting such areas from the larger dangers of climate change requires addressing local threats, for example overfishing, fertilizer pollution and land clearing — all of which can exacerbate the effects of climatic extremes, such as heat waves and droughts. Continue reading
Filed under: Environment, biodiversity, endangered species, coral reefs | Tagged: Environment, climate change, world heritage sites, Amazon Rainforest, Great Barrier Reef, pollution | Leave a comment »
Posted on April 15, 2014 by Bob Berwyn
A NASA photo taken from the International Space Station shows sunlight glinting off the Amazon River.
Drought the main driver of destructive fires
By Staff Report
FRISCO — Longer droughts, land-use changes and wildfires may be pushing parts of the Amazon rainforest toward an ecological tipping point, a team of scientists said after analyzing the effects of fire in a series of study plots.
The changes may abruptly increase tree mortality and change vegetation over large areas, the researchers said, pointing out that current Amazon forest models don’t include the impacts of wildfires. As a result, projections of future forest health tend to underestimate the amount of tree death and overestimate overall forest health, said Dr. Michael Coe, of the Woods Hole Research Center. Continue reading
Filed under: climate and weather, Drought, Environment, global warming | Tagged: Amazon Rainforest, drought, Environment, Wildfires | Leave a comment »
Posted on November 15, 2013 by Bob Berwyn
California’s redwood forests recycle ocean fog to create their own microclimate. bberwyn photo.
Amazon rainforest may be more resilient than previously believed
By Summit Voice
FRISCO — As one of the Earth’s big lungs, the fate of the Amazon rainforest in the face of global warming is a critical climate question. New research suggests that, with strong conservation measures in place, the rainforest may be more able to cope with dry conditions than projected by other studies.
Many climate models over-predict the water stress plants feel during the dry season because they don’t take into account the moisture that the forest itself can recycle in times of drought. In this study, published in the Journal of Climate, the researchers removed unrealistic water stress from their model and found that the moisture that is recycled by the forest is sufficient to reduce the intensity of drought conditions. Continue reading
Filed under: climate and weather, Drought, Environment, forests | Tagged: Amazon Rainforest, climate, drought, forests | Leave a comment »
Posted on November 8, 2013 by Bob Berwyn
Shifts in precipitation patterns would have big consequences for agriculture, forests and municipal water supplies
Research suggests that deforestation will likely produce a weather cycle over the Amazon consisting of abnormally dry air in the sun-scorched northern Amazon around the equator weighted by wetter air in the cooler south (left). The Princeton-led researchers found that the Amazon pattern would be subject to meandering high-altitude winds known as Rossby waves that move east or west across the planet (center). The Rossby waves would move the dry end of the Amazon pattern directly over the western United States from December to February, while the pattern’s rainy portion would be over the Pacific Ocean south of Mexico (right). Image courtesy Princeton University.
By Summit Voice
FRISCO — Continued deforestation in the Amazon region could have significant impacts on the weather in North America, according to Princeton researchers, who used fine-grained climate models to simulate how precipitation patterns could shift in the future.
Their findings suggest that total deforestation of the Amazon may significantly reduce rain and snowfall in the western United States — specifically, 20 percent less rain for the coastal Northwest and a 50 percent reduction in the Sierra Nevada snowpack, a crucial source of water for cities and farms in California.
“The big point is that Amazon deforestation will not only affect the Amazon — it will not be contained. It will hit the atmosphere and the atmosphere will carry those responses,” said lead author David Medvigy, an assistant professor of geosciences at Princeton. Continue reading
Filed under: climate and weather, Drought, El Niño, Snow and weather | Tagged: Amazon Rainforest, climate, drought, El Nino, western U.S. | 1 Comment »
Posted on October 22, 2013 by Bob Berwyn
New study says IPCC projections are too conservative
By Summit Voice
FRISCO — In a classic case of climate disruption, research shows that the dry season in southern Amazonia has lengthened by about one week per decade since 1979. Parts of the region may not be able to support rainforest vegetation much longer. A big forest die-back could trigger the release of large volumes of the greenhouse gas carbon dioxide into the atmosphere, a team of scientists warned this week.
The changes could disrupt plant and animal communities in one of the regions of highest biodiversity in the world, said University of Texas professor Rong Fu, who led the team of scientists. Continue reading
Filed under: climate and weather, Drought, Environment, global warming, greenhouse gases | Tagged: Amazon Rainforest, Climate disruption, global warming, Intergovernmental Panel on Climate Change, IPCC | Leave a comment »
Posted on July 15, 2013 by Bob Berwyn
More than two-thirds of the species at risk from global warming haven’t been targeted for conservation
By Summit Voice
FRISCO —Global warming hasn’t been a key consideration in long-term conservation planning, which means that most species at greatest risk from climate change are not currently prioritized for conservation, according to an International Union for Conservation of Nature study that has introduced a pioneering method to assess the vulnerability of species to climate change.
The paper, published in the journal PLOS ONE, is one of the biggest studies of its kind, assessing all of the world’s birds, amphibians and corals. It draws on the work of more than 100 scientists over a period of five years, including Wits PhD student and leader of the study, Wendy Foden. Download the study here. Continue reading
Filed under: biodiversity, climate and weather, endangered species, Environment, global warming | Tagged: Amazon Rainforest, climate, climate change, global warming, IUCN Global Species Programme, IUCN Red List | Leave a comment »
Posted on January 20, 2013 by Bob Berwyn
More frequent droughts take a toll on forest canopy
A megadrought starting in 2005 resulted in widespread damaged to the canopy of the Amazon rainforest. Photo courtesy NASA/JPL-Caltech.
By Summit Voice
FRISCO — With climate scientists warning that droughts are likely to become more frequent and severe as global temperatures continue to climb, a recent study led by NASA scientists shows what that could mean for the Amazon rainforest.
After analyzing more than 10 years worth of satellite data collected from over the Amazon region, the researchers said rainforest damage first observed during the start of a megadrought in 2005 persisted the next several years, even as rainfall gradually rose back to average levels. But another dry period that started in 2010 may exacerbate the impacts, suggesting that the Amazon rainforests may be showing the first signs of potential large-scale degradation due to climate change. Continue reading
Filed under: climate and weather, Drought, global warming | Tagged: Amazon Rainforest, Amazonia, climate change, drought, global warming, NASA | Leave a comment »