tagged w/ CO2
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China spurred a jump in global carbon dioxide (CO2) emissions to their highest ever recorded level in 2011, offsetting falls in the United States and Europe, the International Energy Agency (IEA) said on Thursday.
CO2 emissions rose by 3.2 percent last year to 31.6 billion metric tons (34.83 billion tons), preliminary estimates from the Paris-based IEA showed.
China, the world's biggest emitter of CO2, made the largest contribution to the global rise, its emissions increasing by 9.3 percent, the body said, driven mainly by higher coal use.
"When I look at this data, the trend is perfectly in line with a temperature increase of 6 degrees Celsius (by 2050), which would have devastating consequences for the planet," Fatih Birol, IEA's chief economist told Reuters.
Scientists say ensuring global average temperatures this century do not rise more than 2 degrees Celsius above pre-industrial levels is needed to limit devastating climate effects like crop failure and melting glaciers.
They believe that is only possible if emission levels are kept to around 44 billion metric tons of CO2 equivalent in 2020.
Negotiators from over 180 nations are meeting in Bonn, Germany, until Friday to work towards getting a new global climate pact signed by 2015.
The aim is to ensure ambitious emissions cuts are made after the Kyoto Protocol expires at the end of this year.
Procedural wrangling and a reluctance to raise ambitions to cut emissions due to economic constraints is threatening progress, however. (ID:nL5E8GLCRU]
"I think it would be unrealistic to think that there will be major breakthroughs very soon," Birol said.
"Climate change is sliding down in the international policy agenda, which is definitely a worrying trend."
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Oyster hatcheries along the Washington and Oregon coastlines began experiencing calamitous die-offs beginning in 2006. Scientists suspected they were because of increased carbon dioxide levels in the air that were causing ocean acidification. That theory has now proved out, according to a study just published by the journal Limnology and Oceanography.
Researchers studied oysters at Oregon’s Whiskey Creek Hatchery in 2009 after the hatchery reported that oyster production had declined by as much as 80 percent in recent years. The scientists paid close attention to the seawater that had bathed the oysters. Oceans absorb a significant portion of carbon dioxide in the air and when they do so a chemical process takes place called acidification. Laboratory studies have already shown that elevated carbon dioxide changes the pH and reduces the availability of calcium carbonate in the seawater. And calcium carbonate minerals are the material that sea creatures like oysters and corals use for building shells and skeletons.
The study breaks new ground, according to its authors, because this is the first time these theories on the impact of ocean acidification that were tested in laboratories were verified on an actual commercial shellfish farm with ambient ocean waters. The findings linked the production failures of the farms to the carbon dioxide levels in the seawater in which the larval oysters were spawned and spent the first 24 hours of their lives. That is the time when oysters start to develop their first shells.
“I think that the clear take-home message from this research is that for the oceans, the Pacific Oyster larvae are the ‘canaries in the coal mines’ for ocean acidification. When the CO2 levels in the ocean are too high, they die; when we lower the CO2 levels, they live,” Richard A. Feely, a co-author of the study and senior scientist at the National Oceanic and Atmospheric Administration, said in a statement released by the Center for Biological Diversity.
The center is deeply invested in the findings because in 2009, it filed a lawsuit demanding that the Environmental Protection Agency address ocean acidification in the waters off Washington State under the Clean Water Act. In a settlement, the E.P.A. agreed that states had a duty to look at the impact of ocean acidification. But the implication for sea life is national and global in scale.
“Oyster die-offs are an unmistakable warning that our oceans are in trouble and we’ve got to cut the carbon pollution if we want to have oysters, corals and whales,” said Miyoko Sakashita, oceans director for the center, which last week petitioned the White House and E.P.A. to develop a national plan to address ocean acidification.Oyster hatcheries along the Washington and Oregon coastlines began experiencing... more
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The ongoing rapid retreat of Arctic sea ice is often interpreted as the canary in the mine for anthropogenic climate change. In a new study, scientists have now systematically examined the validity of this claim. They find that neither natural fluctuations nor self-acceleration can explain the observed Arctic sea-ice retreat. Instead, the recent evolution of Arctic sea ice shows a strong, physically plausible correlation with the increasing greenhouse gas concentration. For Antarctic sea ice, no such link is found - for a good reason.
When scientists try to attribute some observed climatic change to a specific forcing, they usually use complex climate models. The scientists at Germany's Max Planck Institute for Meteorology (MPI-M), however, decided on a different strategy as they set out to identify the main driver for the observed sea-ice loss in the Arctic. Dirk Notz, lead author of the study that was now published in the journal Geophysical Research Letters [1], explains why: "Sea ice is so thin that it reacts very sensitive to the large natural fluctuations of weather and climate that prevail in the Arctic. Because these fluctuations are inherently chaotic, their specific timing cannot be reproduced by standard climate models. Such models therefore aren't necessarily the best tool to examine if natural fluctuations did cause the observed sea-ice loss."
The scientists instead used a historical record that described the natural variations of sea-ice extent between the early 1950s and late 1970s. These natural fluctuations were then compared to the magnitude of fluctuations of the Arctic sea-ice cover as measured from satellites since the late 1970s. From such comparison, the scientists found only a minute chance that the recently observed extreme sea-ice minima simply happened by chance - and they could exclude self acceleration as the main driver for the observed sea-ice retreat. "Whenever we had a strong sea-ice loss from one year to the next, the ice cover always recovered somewhat in the following year," explains Dirk Notz. This would not be the case if the sea-ice retreat were indeed self-accelerating.
Jochem Marotzke, Director at MPI-M and co-author of the study, describes what the scientists did next: "Having excluded natural fluctuations and self acceleration as the main driver for the sea-ice retreat, it was clear to us that some external driver was responsible for the observed sea-ice decline. We therefore set out to find an external driver that showed a physically plausible relationship with the observed sea-ice retreat." The scientists examined, for example, the strength of solar radiation. "Here, a physically plausible link to the observed sea-ice retreat can only be established if solar radiation had increased in recent years." However, solar radiation has slightly decreased in the past decades. Its fluctuations are therefore very unlikely to be the main driver of the observed sea ice loss. The scientists could not find a plausible link to changes in prevailing wind patterns, volcanic eruptions, oceanic heat transport, or cosmic rays, either.
"In the end, only the increase in greenhouse gas concentration showed a physically plausible link with the observed sea-ice retreat.
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Enbridge, the Canadian oil giant responsible for a massive tar sands oil spill into the Kalamazoo River in Michigan not yet two years ago, now wants to pipe tar sands oil—the world’s dirtiest oil—through New England with its Trailbreaker pipeline project.
The Trailbreaker tar sands pipeline project
In August 2011, Enbridge filed a permit application with Canada’s National Energy Board to revive a previous tar sands project, called Trailbreaker. Trailbreaker would transport tar sands oil along an approximately 750-mile route from Ontario and Quebec in Eastern Canada through Vermont, New Hampshire, and terminating in Portland, Maine’s Casco Bay, where the oil would be exported into the international market on super tankers.
The oil industry’s scheme to link the Midwestern pipeline system through eastern Canada and across New England to East Coast ports for export to refineries in the Gulf Coast or overseas was shelved a few years ago and defined as commercially nonviable. The Trailbreaker project would reverse the direction of oil flowing through two major pipelines—Enbridge Line 9 and the Portland/Montreal Pipeline.
Enbridge’s permit application to the Canadian National Energy Board for their Line 9 pipeline reversal is an indication that it’s once again putting the Trailbreaker project back on the table. Although Enbridge has claimed this is a standalone project, the application appears to signal the rebirth of Trailbreaker.
By dividing up the project into two smaller segments, Enbridge could be attempting to shield itself from the type of scrutiny faced by tar sands pipelines like TransCanada’s Keystone XL. Enbridge acknowledged in late 2011 that it was actively pursuing plans to bring tar sands to Ontario, Quebec, and New England.
Tar sands: more toxic than conventional oil
The extraction and processing of tar sands oil is one of the largest industrial operations in the world. Tar sands extraction requires strip mining huge tracts of the pristine Boreal Forest in Alberta, Canada—an area the size of Florida is slated for extraction.
Tar sands oil emits three times more greenhouse gases during production than conventional gasoline and about three barrels of water are polluted and dumped in toxic pools (called tailing ponds) for every barrel of oil produced. These processes use enough energy to make tar sands oil production the fastest-growing contributor to Canada’s carbon pollution and the continent’s biggest carbon bomb.
Tar sands extraction also harms the health and cultural traditions of indigenous communities living downstream from the extraction sites and has been connected to high rates of rare cancers, renal failure, lupus, and hyperthyroidism in the area.
Tar sands pipelines: built to spill
Tar sands pipelines have an abysmal safety record, with a spill rate three times the national average for conventional oil in some parts of the US, putting communities at risk of devastating oil spills and pollution to air and drinking water.
Pipeline safety regulators at the Department of Transportation haven’t yet studied the safety of pipelines that carry tar sands crude or set forth specialized regulations for such pipelines, despite safety concerns unique to corrosive tar-sands oil compared to conventional crude oil. These pipelines must operate at higher temperatures and pressures to move the thick tar sands through a pipe and are subject to severe problems with leak detection and safety issues from the unstable mixture. Tar sands crude is particularly dangerous for older pipelines like the Trailbreaker pipelines, which were constructed during World War II.
Enbridge was responsible for a million gallon tar sands oil spill into the Kalamazoo River in Michigan in June 2010. Two years later, the clean-up costs have surpassed $700 million, residents are still sick from the spill’s toxins, small businesses are still hurting, property values are down, and miles of river remain closed. Now Enbridge wants to pipe tar sands oil through New England with its Trailbreaker project.
Trailbreaker: threatening New England’s natural and cultural landscapes
Trailbreaker would cut through New England's most important waters, including Sebago Lake, home to a native species of landlocked Atlantic salmon and the major drinking water resource for greater Portland, Maine’s largest metropolitan area. It also terminates at Casco Bay, a large, rich estuary near Portland, Maine that is home to a variety of coastal natural resources and a thriving marine economy.
Trailbreaker would also put at risk Grand River Basin, Lake Ontario, the Saint Lawrence River, Victory State Forest, and Androscoggin River. A spill along Trailbreaker’s corridor could harm rivers, lakes, and bays that are vital resources for millions of people in Canada and the United States.
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Since 2001, 10 Northeast states that participated in the Regional Greenhouse Gas Initiative have proved to be pioneers in reducing fossil fuel pollution and creating a clean energy economy, according to a report released Wednesday by Environment Connecticut.
Between 2001 and 2009, the six New England states along with New York, New Jersey, Maryland and Delaware cut per capita carbon dioxide emissions 20 percent faster than the rest of the nation. In those years, the Northeast's total economic output per capita grew 87 percent faster than the rest of the nation, the report said.
"Those figures challenge the claim that reducing emissions undermines economic growth," said Johanna Neumann, regional director of Environment Connecticut, which is based in West Hartford.
Instead of being a burden on economic development, tighter emission standards and energy conservation, have "not come at the expense of the economy," the report said.
Overall, the 10 states reduced the creation of carbon dioxide from energy use by nearly 18 percent between 2000 to 2009. During that same period, per capita gross domestic product in the 10 states increased by more than 8 percent, while the rest of the nation experienced a 4.5 percent increase in per capita GDP, the report said.
Participating northeastern states have realized nearly $1.6 billion in consumer savings, according to a study last year by the Analysis Group, the report said.
"The initiative requires polluters to pay for the right to emit carbon pollution. Those payments are invested in programs to install more efficient lighting, heating and power generating equipment.
"In Connecticut, the proceeds — more than $51 million so far — go to improving energy efficiency, which in turn funds companies that put weatherizers, electricians and contractors to work," Neumann said.
At 14 percent Maryland had the highest increase in GDP per capita even as it reduced per capita emissions by 15 percent; Connecticut, which reduced per capita emissions by 20 percent experienced a 4 percent gain in GDP, the study said.
In particular, the Northeast states have been vanguards in implementing strict power plant and vehicle emissions standards, improving energy efficiency and adopting aggressive renewable energy standards to increase production of wind, solar and other renewable energy sources, the report said.
The key to those successes has been the willingness of state leaders to work across state lines and partisan divides, the report said.
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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.
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A detailed analysis of global nitrogen cycles shows without a doubt that a spike in atmospheric nitrous oxide can be traced to increased fertilizer use during the past 50 years.
Since 1970, nitrous oxide concentrations have increased by 20 percent, from below 270 parts per billion to more than 320 ppb. After carbon dioxide and methane, nitrous oxide (N2O) is the most potent greenhouse gas, trapping heat and contributing to global warming. It also destroys stratospheric ozone, which protects the planet from harmful ultraviolet rays.
Climate scientists have assumed that the cause of the increased nitrous oxide was nitrogen-based fertilizer, which stimulates microbes in the soil to convert nitrogen to nitrous oxide at a faster rate than normal.
The new study, reported in the April issue of the journal Nature Geoscience, uses nitrogen isotope data to identify the unmistakable fingerprint of fertilizer use in archived air samples from Antarctica and Tasmania.
“Our study is the first to show empirically from the data at hand alone that the nitrogen isotope ratio in the atmosphere and how it has changed over time is a fingerprint of fertilizer use,” said study leader Kristie Boering, a UC Berkeley professor of chemistry and of earth and planetary science.
“We are not vilifying fertilizer. We can’t just stop using fertilizer,” she said. “But we hope this study will contribute to changes in fertilizer use and agricultural practices that will help to mitigate the release of nitrous oxide into the atmosphere.”
The steep rise in atmospheric nitrous oxide coincided with the green revolution of the 1960s, when inexpensive, synthetic fertilizer and other developments boosted food production worldwide, feeding a burgeoning global population.
Tracking the origin of nitrous oxide in the atmosphere, however, is difficult because a molecule from a fertilized field looks identical to one from a natural forest or the ocean if you only measure total concentration. But a quirk of microbial metabolism affects the isotope ratio of the nitrogen the N2O microbes give off, producing a telltale fingerprint that can be detected with sensitive techniques.
Global warming impacts
Limiting nitrous oxide emissions could be part of a first step toward reducing all greenhouse gases, Boering said. In particular, reducing nitrous oxide emissions can initially offset more than its fair share of greenhouse gas emissions overall, since N2O traps heat at a different wavelength than CO2 and clogs a “window” that allows Earth to cool off independent of CO2 levels.
“On a pound for pound basis, it is really worthwhile to figure how to limit our emissions of N2O and methane,” she said. “Limiting N2O emissions can buy us a little more time in figuring out how to reduce CO2 emissions.”
One approach, for example, is to time fertilizer application to avoid rain, because wet and happy soil microbes can produce sudden bursts of nitrous oxide. Changes in the way fields are tilled, when they are fertilized and how much is used can reduce N2O production.
Boering’s studies, which involve analyzing the isotopic fingerprints of nitrous oxide from different sources, could help farmers determine which strategies are most effective. It could also help assess the potential negative impacts of growing crops for biofuels, since some feedstocks may require fertilizer that will generate N2O that offsets their carbon neutrality.
“This new evidence of the budget of nitrous oxide allows us to better predict its future changes– and therefore its impacts on climate and stratospheric ozone depletion – for different scenarios of fertilizer use in support of rising populations and increased production for bio-energy,” said coauthor David Etheridge of the Centre for Australian Weather and Climate Research in Aspendale, Victoria.
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The disappearance of Arctic sea ice has crossed a "tipping point" that could soon make ice-free summers a regular feature across most of the Arctic Ocean, says a British climate scientist who is setting up an early warning system for dangerous climate tipping points.
Tim Lenton at the University of Exeter has carried out a day-by-day assessment of Arctic ice-cover data collected since satellite observation began in 1979. He presented his hotly anticipated findings for the first time at the Planet Under Pressure conference in London on Monday.
Up until 2007, sea ice systematically fluctuated between extensive cover in winter and lower cover in summer. But since then, says Lenton, the difference between winter and summer ice cover has been a million square kilometres greater than it was before, as a result of unprecedented summer melting. These observations are in contrast to what models predict should have happened.
Permanent alteration
Despite fears of runaway sea-ice loss after summer cover hit an all-time low in 2007 – opening the Northwest Passage for the first time in living memory – modelling studies based on our best understanding of ice dynamics indicated the ice cover should fully recover each winter. "They suggest that even if the ice declined a large amount in one year, it should bounce back," says Walt Meier of the US National Snow and Ice Data Center in Boulder, Colorado.
Instead, Lenton's research shows a permanent alteration. According to data from the past five years, the Arctic sea ice has not recovered from the 2007 extreme low. "The system has passed a tipping point," he says.
What caused the change is still unclear. Lenton speculates that the exceptional low in 2007 (pictured, above right) might have allowed the ocean to absorb so much heat that a lot of the thicker multiyear ice, which used to persist through the summer, was melted. Alternatively, the loss of ice may have changed air circulation patterns above the Arctic in ways that have similarly "locked in" the change.
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Edward Lu isn’t the easiest guy in the world to impress. He’s not only an astrophysicist and an electrical engineer, but also an astronaut who’s flown on the Space Shuttle (twice) and the International Space Station — and on top of that, he ran Google’s Advanced Projects Group that gave Google Maps and Google Earth their imaging capabilities.
Then, last year, Lu heard about a technology so simple yet powerful that it could fundamentally change the way oceanographers, meteorologists, fisheries experts and climate scientists gather their data — so he signed on with a company called Liquid Robotics, which owns the technology, as Chief of Innovative Applications. “It seemed like chance to get in on something that can really change way we monitor the ocean,” he said.
“It” is the Wave Glider, a surfboard-shaped apparatus, about 7 feet long, that can sail the open seas propelled by nothing more than wave power. Just last week, a flotilla of four Wave Gliders arrived in Hawaii after a months' long excursion that started in California last November, and they’ll soon be continuing on toward Australia and Japan. For people who keep track of such things, the little vessels have already shattered the Guinness Book World record for distance by an unmanned wave-powered vehicle. “It can go essentially forever,” Lu said, “until it’s covered with barnacles.” (That hasn’t happened yet.)
But for people who care about what human-caused global warming is doing to the oceans, in particular, and the climate more generally, the Wave Glider could turn out to be pretty important. The way it works is completely straightforward: the surfboard part of the device, made of carbon fiber and plastic foam, is connected by a tether about 20 feet long to an underwater “glider,” fitted out with hinged flaps. “It’s kind of like a Venetian blind that lies horizontally,” Lu said.
At 20 feet down, the water is pretty still, so when the surfboard is lifted by a wave, it yanks the glider upward. That makes the flaps angle forward, and propels the whole assembly forward at about 1.5 knots. When the surfboard drops into a trough between two waves, the weighted glider pulls the assembly downward, putting the flaps in a position that moves everything forward as well (it’s hard to describe in words, but there’s a video that helps).
The surfboard itself is covered with solar panels that power any scientific instruments on board, along with a transmitter that uses Iridium satellites to send data to, and receive commands from, a control room at company headquarters in Sunnyvale, Calif. What that data consists of depends on which customer has signed up as a client — oil companies, for example, which uses Wave Gliders to sniff for leaks around drilling rigs and undersea pipelines; or the Scripps Institution of Oceanography, which uses them to tow earthquake-monitoring sensors; or the National Oceanic and Atmospheric Administration (NOAA), which uses them to gather carbon dioxide data out at sea where sensing buoys are few and far between. “Over the world’s oceans as a whole,” Lu said, “there are maybe 5,000 or 6,000 buoys, which amounts to two, on average, for an area the size of California.”
Not only could a fleet of Wave Gliders add dramatically to that sparse coverage, Lu said, but it could also fill a crisis that faces climate science: a looming gap in satellite observations as budget problems allow older satellites to fail without new ones ready to go. “We have an uninterrupted 30-year record of climate observations,” Lu said, but if there’s no overlap between older satellites and new ones, there’s no way to calibrate the two to make sure they’re making measurements consistently. It’s kind of like trying to carry out a commando mission without everyone synchronizing their watches.
By Michael D. Lemonick
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“It would be immoral to leave these young people with a climate system spiraling out of control.”
by Dan Miller
NASA climate scientist James Hansen gave a talk at the TED conference in Long Beach, CA on February 29th where he laid out the case for taking urgent action to reduce greenhouse emissions.
Dr. Hansen’s talk began by describing his personal journey, originally studying Venus under Prof. James Van Allen and then working at NASA on an instrument to study Venus’ atmosphere. But after being asked to do some calculations of Earth’s greenhouse effect, Dr. Hansen resigned from the Venus mission to work full time studying Earth’s atmosphere “because a planet changing before our eyes is more interesting and important – its changes will affect all humanity.”
Dr. Hansen and some colleagues published a 1981 paper in Science Magazine that concluded that “observed warming of 0.4C in the prior century was consistent with the greenhouse effect of increasing CO2, — that Earth would likely warm in the 1980s, — and warming would exceed the noise level of random weather by the end of the century. We also said that the 21st century would see shifting climate zones, creation of drought prone regions in North America and Asia, erosion of ice sheets, rising sea levels, and opening of the fabled Northwest passage. All of these impacts have since either happened or are now well underway.”
Dr. Hansen went on to explain that, after speaking out for the need for an energy policy that would address climate change, the White House contacted NASA and Dr. Hansen was ordered to not speak to the media without permission. After informing the New York Times about the situation, the censorship was lifted and Dr. Hansen continued to speak out, justifying his actions with the first line of NASA’s Mission Statement’: “To understand and protect the home planet”. But there were consequences… the reference to the home planet was soon struck from NASA’s Mission Statement, never to return.
Dr. Hansen then went on to describe some of the recent science, including a detailed look at the Earth’s energy imbalance that was made possible by data from 3000 “Argo” floats that measure ocean temperature at different depths. Dr. Hansen said that the current imbalance of 0.6 watts/square meter (which does not include the energy already used to cause the current warming of 0.8°C) was equivalent to exploding 400,000 Hiroshima atomic bombs every day, 365 days per year.
Favorite denier myths such as “it’s the Sun” and “CO2 lags temperature” were addressed by Dr. Hansen and shown to be wrong or irrelevant. He also discussed how amplifying feedbacks in the past took small changes in temperature due to slight changes in the Earth’s orbit and either initiated or ended ice ages. He then said these same amplifying feedbacks will occur today if we do not stop the warming. ”The physics does not change.”
Besides the impacts that are already occurring, Dr. Hansen said that if we do not stop the warming, we should expect sea levels to rise this century by 1 to 5 meters (3 to 18 feet), extinction of 20 to 50% of species, and massive droughts later this century. He said that the recent Texas heat wave, Moscow’s heat wave the year before, and the 2003 heat wave in Europe we “exceptional” events that now occur 25 to 50 times more often than just 50 years ago. Therefore, he concluded, we can say with high confidence that these heat waves were “caused” by global warming.
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This is an incredible presentation by photogtapher Garth Lenz showing shocking photographs of the devastation of tarsands along with the beautiful ecosystems threatened by them. Even he could not hold back his emotion when relaying the effects on indigenous communities and the responsibilty we all have in stopping this atrocity of nature before it is too late.This is an incredible presentation by photogtapher Garth Lenz showing shocking... more
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Current rate of acidification faster than at any time during the past 300 million years
The world’s oceans are acidifying at 10 times the rate measured during some previous major climate shifts, a change that doesn’t bode well for many familiar ocean species.
“What we’re doing today really stands out,” said researcher Bärbel Hönisch, referring to emissions of climate-altering greenhouse gases. Hönisch is lead author of a recent paper that compares the current episode of acidification with four other great extinction events.
“We know that life during past ocean acidification events was not wiped out. New species evolved to replace those that died off. But if industrial carbon emissions continue at the current pace, we may lose organisms we care about—coral reefs, oysters, salmon, said Hönisch, a paleoceanographer at Columbia University’s Lamont-Doherty Earth Observatory.
Published in Science, the study is the first of its kind to survey the geologic record for evidence of ocean acidification over this vast time period.
The decisions we make over the next few decades could have significant implications on a geologic timescale,” said Richard Feely, an oceanographer at the National Oceanic and Atmospheric Administration. It may take decades before ocean acidification’s effect on marine life shows itself, he explained. Until then, the past is a good way to foresee the future.
“These studies give you a sense of the timing involved in past ocean acidification events—they did not happen quickly,” he said.
The oceans act like a sponge to draw down excess carbon dioxide from the air; the gas reacts with seawater to form carbonic acid, which over time is neutralized by fossil carbonate shells on the seafloor. But if CO2 goes into the oceans too quickly, it can deplete the carbonate ions that corals, mollusks and some plankton need for reef and shell-building.
That is what is happening now. In a review of hundreds of paleoceanographic studies, a team of researchers from five countries found evidence for only one period in the last 300 million years when the oceans changed even remotely as fast as today: the Paleocene-Eocene Thermal Maximum, about 56 million years ago.
Previous research showed that, within a span of about 5,000 years, a mysterious surge of carbon doubled atmospheric concentrations, pushed average global temperatures up by about 6 degrees celsius, and dramatically changed the ecological landscape.
Carbonate plankton shells littering the seafloor dissolved, leaving brown mud that was the telltale sign for paleoclimatologists who discovered the layer near Antarctica.
As many as half of all species of benthic foraminifers, a group of single-celled organisms that live at the ocean bottom, went extinct, suggesting that organisms higher in the food chain may have also disappeared, said study co-author Ellen Thomas, a paleoceanographer at Yale University who was on that pivotal Antarctic cruise.
“It’s really unusual that you lose more than 5 to 10 percent of species over less than 20,000 years,” Thomas said. “It’s usually on the order of a few percent over a million years.” During this time, scientists estimate, ocean pH—a measure of acidity–may have fallen as much as 0.45 units. (As pH falls, acidity rises.)
In the last hundred years, atmospheric CO2 has risen about 30 percent, to 393 parts per million, and ocean pH has fallen by 0.1 unit, to 8.1–an acidification rate at least 10 times faster than 56 million years ago, according to Hönisch.
snip
In a recent study, scientists from Stony Brook University found that the larvae of bay scallops and hard clams grow best at pre-industrial pH levels, while their shells corrode at the levels projected for 2100. Off the U.S. Pacific Northwest, the death of oyster larvae has recently been linked to the upwelling of acidic water there.
In parts of the ocean acidified by underwater volcanoes venting carbon dioxide, scientists have seen alarming signs of what the oceans could be like by 2100. In a 2011 study of coral reefs off Papua New Guinea, scientists writing in the journal Nature Climate Change found that when pH dropped to 7.8, reef diversity declined by as much as 40 percent. Other studies have found that clownfish larvae raised in the lab lose their ability to sniff out predators and find their way home when pH drops below 7.8.
“It’s not a problem that can be quickly reversed,” said Christopher Langdon, a biological oceanographer at the University of Miami who co-authored the study on Papua New Guinea reefs. “Once a species goes extinct it’s gone forever. We’re playing a very dangerous game.”
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I have been a member of Tree Nation for going on five years now. Tree Nation is a free Internet community/organization where you can be a part of planting thousands of trees in four separate forests globally to help counter deforestation and desertfication right from your modem. Their original forest in the heart of Niger has now planted over 52,000 trees on their way to the goal of 100,000 for 2012! All total over 397,000 trees have been planted. I have several trees planted there in my name as well. There are other forests in Columbia, Nicaragua and their newest in Madagascar. This article is about a new moringa park being introduced in Niger and also about beginning to use agroforestry in their Niger plantation.
We see so much deforestation taking place in our world and so many negative effects from our behavior. This is one bright spot proving that people globally can join together in good spirit to work to make the world a better place.I hope you check it out and maybe even become part of the solution in planting trees in places where they are most needed now.
Excerpt:
"Alongside planting trees, we are beginning to farm fruits and vegetables as we cultivate the trees planted. Our goal is twofold: to enhance the quality of the soil and the growth of the trees through agroforestry and to take advantage by selling the products farmed in the process.
So far, we have planted tomatoes, aubergines and cucumbers. While the first two have yielded good results, many cucumbers have been lost owing to the pest of caterpillars. We are, however, going to continue farming the vegetables and we hope to make the most of distribution outlets in the capital of Niamey and in local markets to sell them alongside our production of Moringa leaves.
The Moringa plantation:
We have also decided to reorganise our site to open a new Moringa park. 15 metres wide, it runs alongside the channelling strip used for channelling the irrigation from the basin, which is a round 200 metres long. It will be ideally placed to take advantage of the water well and our soon-to-be-in-place micro irrigation system, by using the border irrigation technique, which involves irrigating a whole area of land at one time. As for our old park, until the irrigation system has been expanded it will only be being farmed on a seasonal basis.
In all, over the last few months we have harvested around 200 kg of Moringa leaves. And, while we’re on the subject, we thought you might want to know that we’ve just collected our first Baobab leaves since they were planted 4-5 years ago!"I have been a member of Tree Nation for going on five years now. Tree Nation is a free... more
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Last year the Arctic, which is warming faster than anywhere else on Earth due to global climate change, experienced its warmest twelve months yet. According to recent data by NASA, average Arctic temperatures in 2011 were 2.28 degrees Celsius (4.1 degrees Fahrenheit) above those recorded from 1951-1980. As the Arctic warms, imperiling its biodiversity and indigenous people, researchers are increasingly concerned that the region will hit climatic tipping points that could severely impact the rest of the world. A recent commentary in Nature Climate Change highlighted a number of tipping points that keep scientists awake at night.
"If set in motion, [tipping points] can generate profound climate change which places the Arctic not at the periphery but at the core of the Earth system," Professor Duarte, a climatologist with the University of Western Australia's Ocean Institute and co-author other paper, said in a press release. "There is evidence that these forces are starting to be set in motion. This has major consequences for the future of human kind as climate change progresses."
One of the tipping points is sea ice loss. The Arctic wasn't just relatively hot last year—beating the previous record set in 2010 by 0.17 degrees Celsius (0.3 degrees Fahrenheit)—it also experienced the lowest sea ice volume yet recorded, and the second-lowest extent. Sea ice is essential to many Arctic species, from polar bears to walrus, and narwhals to seals. In just over 30 years, sea ice volume has dropped precipitously, declining by 76 percent from 1979 (16,855 cubic kilometers) to 2011 (4,017 cubic kilometers). This loss of sea ice also leads to greater regional and global warming, as the Arctic's sea reflects the sun's light back into space, cooling not only the region but the world.
Sea ice loss may also be having a direct impact on weather in the mid-latitudes. In fact, recent research has suggested that, perhaps unintuitively, the extreme cold spell experienced by Europe this winter was linked to the sea ice decline in the Arctic. Researchers argue that the Arctic Oscillation, which is partially responsible for weather conditions in the Northern Hemisphere in winter, has become unhinged by the sea ice decline, causing more extreme winters, such as Europe's cold spell and the massive blizzards that hit the U.S. in 2009 and 2010.
But it's not just sea ice loss that has produced stark concerns: greenhouse gases from thawing permafrost could be just as disastrous. A study published in Nature late last year warned that greenhouse gas emissions due to permafrost thaw could equal the amount currently emitted by deforestation worldwide, a significantly larger estimate than has been put forward before. Moreover, since permafrost thaw emissions include methane, a more potent greenhouse gas than carbon, it could have an impact 2.5 times larger than deforestation overall.
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Further tipping points include an input of freshwater into the Atlantic Ocean from melting ice and glaciers, already increased by 30 percent, which Durate says "may affect the whole ocean current system and, as a result, the climate at a regional level."
Governments have responded to warming in the Arctic with a resource race. Governments with Arctic territories plan to drastically expand oil and gas exploitation, utilize new shipping routes, and increase mining. The industrialization of the Arctic, according to Duarte, may only accelerate impacts on the fragile region and push tipping points.
"[Arctic tipping points] represents a test of our capacity as scientists, and as societies to respond to abrupt climate change," Duarte said. "We need to stop debating the existence of tipping points in the Arctic and start managing the reality of dangerous climate change. We argue that tipping points do not have to be points of no return. Several tipping points, such as the loss of summer sea ice, may be reversible in principle—although hard in practice. However, should these changes involve extinction of key species—such as polar bears, walruses, ice-dependent seals and more than 1,000 species of ice algae—the changes could represent a point of no return."
The solution, Durate says, is to cut the fossil fuel emissions that are causing climate change.
CITATIONS: Carlos M. Duarte, Timothy M. Lenton, Peter Wadhams, Paul Wassmann. Abrupt climate change in the Arctic. Nature Climate Change, 2012; 2 (2): 60 DOI: 10.1038/nclimate1386.
Schuur, Edward A. G.; Abbott, Benjamin. Climate change: High risk of permafrost thaw. Nature. 480, 32–33. 2011. doi:10.1038/480032a.
Polar bears approach a U.S. attack sub 280 miles from the North Pole in an encounter that would have been unimaginable a century ago. As the sea ice melts and the Arctic warms, many nations see not a climate warming, but an opportunity to exploit the region for resources. Photo by: U.S. Navy.
Read more: http://news.mongabay.com/2012/0213-hance_arctic_tippingpoints.html?utm_source=dlvr.it&utm_medium=twitter#ixzz1mNBb8eGOLast year the Arctic, which is warming faster than anywhere else on Earth due to... more
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Agroecology is the science behind sustainable agriculture, from the ground up.
It combines scientific inquiry with place-based knowledge and experimentation, emphasizing technology and innovations that are knowledge-intensive, low cost, ecologically sound and practical. By listening to farmers, and using the most up-to-date science, agroecology provides a modern framework for thinking broadly about agriculture in terms of its four key systems properties: productivity, resilience, equity and sustainability.
At PAN, we document and publicize the contribution of the agroecological sciences to climate-friendly, sustainable development, profile the successes of local organic farmers and provide technical support on alternatives to our campaign partners.
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Africa :: The push-pull system (PDF) of ecological pest management is transforming small farms in Africa. It illustrates agroecology's ingenuity, as well as the many economic, food security, health and environmental benefits of this approach.
Kenyan maize farmers have tripled their yields by intercropping maize with plants that repel pests, support natural pest predators and suppress weeds. One of the plants, desmodium, is a nitrogen-fixing legume that is also used as fodder for animals. The inclusion of these plants in the farming system reduces synthetic pesticide use and augments livestock feed, providing families with additional milk and meat for consumption or sale. Additional benefits include reduced run-off and soil erosion, enhanced soil fertility, improved food security and family nutrition, and increased household income. More than 12,000 farmers across eastern Africa have adopted the technology, with another 100,000 expected to do so over the next three years.
More stories at the linkAgroecology is the science behind sustainable agriculture, from the ground up.
It... more
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A loss of sea ice could be a cause of the bitter winds that have swept across the UK in the past week, weather experts say
The bitterly cold weather sweeping Britain and the rest of Europe has been linked by scientists with the ice-free seas of the Arctic, where global warming is exerting its greatest influence.
A dramatic loss of sea ice covering the Barents and Kara Seas above northern Russia could explain why a chill Arctic wind has engulfed much of Europe and killed 221 people over the past week.
The death toll from Arctic blast has been particularly severe in the Ukraine, where many of the dead have been people sleeping on the streets. Heating and food tents have been set up to ease their hardship. In Romania 24 people are known to have died and 17 in Poland.
A growing number of experts believe complex wind patterns are being changed because melting Arctic sea ice has exposed huge swaths of normally frozen ocean to the atmosphere above.
In particular, the loss of Arctic sea ice could be influencing the development of high-pressure weather systems over northern Russia, which bring very cold winds from the Arctic and Siberia to Western Europe and the British Isles, the scientists believe. An intense anticyclone over north-west Russia is behind the bitterly cold easterly winds that have swept across Europe and some climate scientists say the lack of Arctic sea ice brought about by global warming is responsible.
"The current weather pattern fits earlier predictions of computer models for how the atmosphere responds to the loss of sea ice due to global warming," said Professor Stefan Rahmstorf of the Potsdam Institute for Climate Impact Research. "The ice-free areas of the ocean act like a heater as the water is warmer than the Arctic air above it. This favours the formation of a high-pressure system near the Barents Sea, which steers cold air into Europe."
Sea ice covering the Barents and Kara Seas has been exceptionally low this winter, according to the US National Snow and Ice Data Centre in Boulder, Colorado. But air temperatures above the Barents and Kara Seas have been higher than average. The relatively mild westerly winds that have kept Britain from freezing much of this winter have been blocked by fierce high pressure over north-west Russia, centred on an area just south of the Barents Sea.
Studies by scientists at the Alfred Wegener Institute for Polar and Marine Research have confirmed a link between the loss of Arctic sea ice and the development of high-pressure zones in the polar region, which influence wind patterns at lower latitudes further south. Scientists found that as the cap of sea ice is removed from the ocean, huge amounts of heat are released from the sea into the colder air above, causing the air to rise. Rising air destabilises the atmosphere and alters the difference in air pressure between the Arctic and more southerly regions, changing wind patterns.
Professor Rahmstorf said the Alfred Wegener study confirms earlier predictions from computer models by Vladimir Petoukhov of the Potsdam Institute, who forecast colder winters in western Europe as a result of melting sea ice.
Dr Petoukhov and his colleague Vladimir Semenov were among the first scientists to suggest a link between the loss of sea ice and colder winters in Europe. Their 2009 study simulated the effects of disappearing sea ice and found that for some years to come the loss will increase the chances of colder winters.
"Whoever thinks that the shrinking of some far-away sea ice won't bother him could be wrong. There are complex interconnections in the climate system, and in the Barents-Kara Sea we might have discovered a powerful feedback mechanism," Dr Petoukhov said.
More at the linkA loss of sea ice could be a cause of the bitter winds that have swept across the UK... more
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The biggest trees in the world, known as the true ecological kings of the jungle, are dying off rapidly as roads, farms and settlements fragment forests and they come under prolonged attack from severe droughts and new pests and diseases.
Big trees may comprise less than 2% of the trees in any forest but they can contain 25% of the total biomass and are vital for the health of the whole forest. Credit: us-parks.com
Long-term studies in Amazonia, Africa and Central America show that while these botanical behemoths may have adapted successfully to centuries of storms, pests and short-term climatic extremes, they are counter-intuitively more vulnerable than other trees to today's threats.
"Fragmentation of the forests is now disproportionately affecting the big trees," said William Laurance, a research professor at James Cook University in Cairns, Australia. "Not only do many more trees die near forest edges, but a higher proportion of the trees dying were the big trees.
"Their tall stature and relatively thick, inflexible trunks, may make them especially prone to uprooting and breakage near forest edges where wind turbulence is increased," Laurance said in this week's New Scientist magazine.
Big trees may comprise less than 2% of the trees in any forest but they can contain 25% of the total biomass and are vital for the health of whole forests because they seed large areas. "With their tall canopies basking in the sun, big trees capture vast amounts of energy. This allows them to produce massive crops of fruits, flowers and foliage that sustain much of animal life in the forests. Their canopies help moderate the local forest environment while their understory creates a unique habitat for other plants and animals," Laurance said.
"Only a small number of tree species have the genetic capacity to grow really big. To grow into giants, trees need good growing conditions, lots of time and the right place to establish their seedlings. Disrupt any one of these and you lose them."
In some parts of the world, Laurance said, populations of big trees are dwindling because their seedlings cannot survive or grow. "In southern India an aggressive shrub is invading the understorey of many forests, preventing seedlings from dropping on the floor. With no young trees to replace them, it's only a matter of time before most of the big trees disappear."
According to Laurance, it is not just the biggest trees in the world that are suffering, but also the biggest in their communities. Dutch elm disease killed off many of the stateliest trees in Britain in the 1960s and 70s, and new exotic organisms and bacterial infections, often brought in from other continents via garden centers, are threatening oak, ash and other species.
Longer lasting and more intense droughts, which are becoming more frequent in many tropical areas with climate change, are also taking their toll. Studies in Puerto Rico and Costa Rica suggest that big trees also suffer more in droughts than most other organisms.
"In rainforests droughts promote surface fires that burn through leaf litter on the forest floor. Larger trees were initially thought to survive these fires but, in fact, many die two to three years later. In cloud forests, big trees use their branches and crowns to rake the mist and capture water droplets. Global warming could push clouds up to higher elevations depriving them of sources of moisture," Laurance said.
"The danger is that the oldest, largest trees will progressively die off and not be replaced. Alarmingly, this might trigger a 'positive feedback' that could destabilize the climate: as older trees die, forests would release their stored carbon, prompting a vicious circle of further warming and forest shrinkage."
more at the linkThe biggest trees in the world, known as the true ecological kings of the jungle, are... more
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The ocean is a delicate place, and tiny changes to its composition can cause serious devastation.
Adding carbon to the atmosphere contributes to global warming and climate change. Another less-discussed impact is ocean acidification—whereby carbon molecules diffuse into the ocean from the atmosphere, causing a steady rise in acidity—even though the impacts are already being felt by many species.
The beautiful blue sea slug, seen here, is one such creature. Blue sea slugs feed on the poisonous Portuguese man of war jellyfish, meaning that an ocean without them would be an ocean with a lot more stinging jellyfish.
This is 1: Blue Sea Slug
More at the link
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The link to humans and the food chain each of these species represents should make people understand just how acidification is affecting us as well.The ocean is a delicate place, and tiny changes to its composition can cause serious... more
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Rising human carbon dioxide emissions may be affecting the brains and central nervous system of sea fishes with serious consequences for their survival, an international scientific team has found.
Carbon dioxide concentrations predicted to occur in the ocean by the end of this century will interfere with fishes' ability to hear, smell, turn and evade predators, says Professor Philip Munday of the ARC Centre of Excellence for Coral Reef Studies and James Cook University.
"For several years our team have been testing the performance of baby coral fishes in sea water containing higher levels of dissolved CO2 - and it is now pretty clear that they sustain significant disruption to their central nervous system, which is likely to impair their chances of survival," Prof. Munday says.
In their latest paper, published in the journal Nature Climate Change, Prof. Munday and colleagues report world-first evidence that high CO2 levels in sea water disrupts a key brain receptor in fish, causing marked changes in their behaviour and sensory ability.
"We've found that elevated CO2 in the oceans can directly interfere with fish neurotransmitter functions, which poses a direct and previously unknown threat to sea life," Prof. Munday says.
Prof. Munday and his colleagues began by studying how baby clown and damsel fishes performed alongside their predators in CO2-enriched water. They found that, while the predators were somewhat affected, the baby fish suffered much higher rates of attrition.
"Our early work showed that the sense of smell of baby fish was harmed by higher CO2 in the water - meaning they found it harder to locate a reef to settle on or detect the warning smell of a predator fish. But we suspected there was much more to it than the loss of ability to smell."
The team then examined whether fishes' sense of hearing - used to locate and home in on reefs at night, and avoid them during the day - was affected. "The answer is, yes it was. They were confused and no longer avoided reef sounds during the day. Being attracted to reefs during daylight would make them easy meat for predators."
Other work showed the fish also tended to lose their natural instinct to turn left or right - an important factor in schooling behaviour which also makes them more vulnerable, as lone fish are easily eaten by predators.
"All this led us to suspect it wasn't simply damage to their individual senses that was going on - but rather, that higher levels of carbon dioxide were affecting their whole central nervous system."
The team's latest research shows that high CO2 directly stimulates a receptor in the fish brain called GABA-A, leading to a reversal in its normal function and over-excitement of certain nerve signals.
While most animals with brains have GABA-A receptors, the team considers the effects of elevated CO2 are likely to be most felt by those living in water, as they have lower blood CO2 levels normally. The main impact is likely to be felt by some crustaceans and by most fishes, especially those which use a lot of oxygen.
Prof. Munday said that around 2.3 billion tonnes of human CO2 emissions dissolve into the world's oceans every year, causing changes in the chemical environment of the water in which fish and other species live.
"We've now established it isn't simply the acidification of the oceans that is causing disruption - as is the case with shellfish and plankton with chalky skeletons - but the actual dissolved CO2 itself is damaging the fishes' nervous systems."
More at the linkRising human carbon dioxide emissions may be affecting the brains and central nervous... more
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By 2100, global climate change will modify plant communities covering almost half of Earth's land surface and will drive the conversion of nearly 40 percent of land-based ecosystems from one major ecological community type - such as forest, grassland or tundra - toward another, according to a new NASA and university computer modeling study.
Researchers from NASA's Jet Propulsion Laboratory and the California Institute of Technology in Pasadena, Calif., investigated how Earth's plant life is likely to react over the next three centuries as Earth's climate changes in response to rising levels of human-produced greenhouse gases. Study results are published in the journal Climatic Change.
The model projections paint a portrait of increasing ecological change and stress in Earth's biosphere, with many plant and animal species facing increasing competition for survival, as well as significant species turnover, as some species invade areas occupied by other species.
Most of Earth's land that is not covered by ice or desert is projected to undergo at least a 30 percent change in plant cover - changes that will require humans and animals to adapt and often relocate.
In addition to altering plant communities, the study predicts climate change will disrupt the ecological balance between interdependent and often endangered plant and animal species, reduce biodiversity and adversely affect Earth's water, energy, carbon and other element cycles.
"For more than 25 years, scientists have warned of the dangers of human-induced climate change," said Jon Bergengren, a scientist who led the study while a postdoctoral scholar at Caltech.
"Our study introduces a new view of climate change, exploring the ecological implications of a few degrees of global warming. While warnings of melting glaciers, rising sea levels and other environmental changes are illustrative and important, ultimately, it's the ecological consequences that matter most."
When faced with climate change, plant species often must "migrate" over multiple generations, as they can only survive, compete and reproduce within the range of climates to which they are evolutionarily and physiologically adapted.
While Earth's plants and animals have evolved to migrate in response to seasonal environmental changes and to even larger transitions, such as the end of the last ice age, they often are not equipped to keep up with the rapidity of modern climate changes that are currently taking place.
Human activities, such as agriculture and urbanization, are increasingly destroying Earth's natural habitats, and frequently block plants and animals from successfully migrating.
More at the linkBy 2100, global climate change will modify plant communities covering almost half of... more
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