by Deep Green Resistance News Service | Sep 1, 2013 | Climate Change
By Jeremy Hance / Mongabay
As if ocean acidification and climate change weren’t troubling enough (both of which are caused by still-rising carbon emissions), new research published in Nature finds that ocean acidification will eventually exacerbate global warming, further raising the Earth’s temperature.
Scientists have long known that tiny marine organisms—phytoplankton—are central to cooling the world by emitting an organic compound known as dimethylsulphide (DMS). DMS, which contains sulfur, enters the atmosphere and helps seed clouds, leading to a global cooling effect. In fact, in the past scientists have believed that climate change may actually increase DMS emissions, and offset some global warming, but they did not take into account the impact of acidification.
Researchers, headed by Katharina Six with the Max Planck Institute for Meteorology, tested how acidification affects phytoplankton in the laboratory by lowering the pH (i.e. acidifying) in plankton-filled water tanks and measuring DMS emissions. When they set the ocean acidification levels for what is expected by 2100 (under a moderate greenhouse gas scenario) they found that cooling DMS emissions fell.
Plugging the results into global modeling system, Six says, “we get an extra warming of 0.23 to 0.48 degree Celsius from the proposed impact [by 2100],” adding that “less sulphur results in a warming of the Earth surface.” This creates a positive feedback loop that will likely have impacts that are anything but positive, according to scientists.
To date, the world has warmed approximately 0.8 degrees Celsius in the last century with a variety of impacts including worsening severe weather, rising sea levels, melting glaciers and sea ice, and imperiled species.
Six also notes that a warmer world does not necessarily mean a more productive world for phytoplankton as has been argued by researchers in the past.
“In former times it was assumed that phytoplankton potentially growth better in a warmer ocean,” she explained to mongabay.com. “However, the basis for plant growth is the supply with nutrients. As the oceans will stabilize in the warmer climate, fewer nutrients will be transported into the sunlight zone. Earth system models, like the MPI-ESM that was used for our study, project a decrease in primary production of 17 percent at the end of this century for a moderate climate scenario. The impact from climate change alone led to a decrease in DMS emission of 7 percent.”
The results are still preliminary as researchers have yet to test how DMS emissions will by impacted in tropical and subtropical waters, focusing to date on polar and temperate waters. In addition, further modeling should be done in order to understand possible uncertainties according to Six.
Still, the evidence is strong enough that the researchers write in the paper that “this potential climate impact mechanism of ocean acidification should be considered in projections of future climate change.” Essentially raising current estimates for a moderate climate scenario by around 10 percent.
Ocean acidification, which has been dubbed “climate change’s equally evil twin” by U.S. National Oceanic and Atmospheric Administration (NOAA)’s Jane Lubchenco, is expected to have largely negative impacts on many marine species, including dissolving the shells of crustaceans and molluscs, hampering coral reefs, and even changing how far fish can hear.
So, how do we stop this from happening?
“There is only one answer,” Katharina Six told mongabay.com, “the abatement of fossil fuel emissions.”
From Mongabay: “Bad feedback: ocean acidification to worsen global warming“
by Deep Green Resistance News Service | Aug 1, 2013 | Climate Change
By Bjorn Carey / Stanford University
The planet is undergoing one of the largest changes in climate since the dinosaurs went extinct. But what might be even more troubling for humans, plants and animals is the speed of the change. Stanford climate scientists warn that the likely rate of change over the next century will be at least 10 times quicker than any climate shift in the past 65 million years.
If the trend continues at its current rapid pace, it will place significant stress on terrestrial ecosystems around the world, and many species will need to make behavioral, evolutionary or geographic adaptations to survive.
Although some of the changes the planet will experience in the next few decades are already “baked into the system,” how different the climate looks at the end of the 21st century will depend largely on how humans respond.
The findings come from a review of climate research by Noah Diffenbaugh, an associate professor of environmental Earth system science, and Chris Field, a professor of biology and of environmental Earth system science and the director of the Department of Global Ecology at the Carnegie Institution. The work is part of a special report on climate change in the current issue of Science.
Diffenbaugh and Field, both senior fellows at the Stanford Woods Institute for the Environment, conducted the targeted but broad review of scientific literature on aspects of climate change that can affect ecosystems, and investigated how recent observations and projections for the next century compare to past events in Earth’s history.
For instance, the planet experienced a 5 degree Celsius hike in temperature 20,000 years ago, as Earth emerged from the last ice age. This is a change comparable to the high-end of the projections for warming over the 20th and 21st centuries.
The geologic record shows that, 20,000 years ago, as the ice sheet that covered much of North America receded northward, plants and animals recolonized areas that had been under ice. As the climate continued to warm, those plants and animals moved northward, to cooler climes.
“We know from past changes that ecosystems have responded to a few degrees of global temperature change over thousands of years,” said Diffenbaugh. “But the unprecedented trajectory that we’re on now is forcing that change to occur over decades. That’s orders of magnitude faster, and we’re already seeing that some species are challenged by that rate of change.”
Some of the strongest evidence for how the global climate system responds to high levels of carbon dioxide comes from paleoclimate studies. Fifty-five million years ago, carbon dioxide in the atmosphere was elevated to a level comparable to today. The Arctic Ocean did not have ice in the summer, and nearby land was warm enough to support alligators and palm trees.
“There are two key differences for ecosystems in the coming decades compared with the geologic past,” Diffenbaugh said. “One is the rapid pace of modern climate change. The other is that today there are multiple human stressors that were not present 55 million years ago, such as urbanization and air and water pollution.”
Record-setting heat
Diffenbaugh and Field also reviewed results from two-dozen climate models to describe possible climate outcomes from present day to the end of the century. In general, extreme weather events, such as heat waves and heavy rainfall, are expected to become more severe and more frequent.
For example, the researchers note that, with continued emissions of greenhouse gases at the high end of the scenarios, annual temperatures over North America, Europe and East Asia will increase 2-4 degrees C by 2046-2065. With that amount of warming, the hottest summer of the last 20 years is expected to occur every other year, or even more frequently.
By the end of the century, should the current emissions of greenhouse gases remain unchecked, temperatures over the northern hemisphere will tip 5-6 degrees C warmer than today’s averages. In this case, the hottest summer of the last 20 years becomes the new annual norm.
“It’s not easy to intuit the exact impact from annual temperatures warming by 6 C,” Diffenbaugh said. “But this would present a novel climate for most land areas. Given the impacts those kinds of seasons currently have on terrestrial forests, agriculture and human health, we’ll likely see substantial stress from severely hot conditions.”
The scientists also projected the velocity of climate change, defined as the distance per year that species of plants and animals would need to migrate to live in annual temperatures similar to current conditions. Around the world, including much of the United States, species face needing to move toward the poles or higher in the mountains by at least one kilometer per year. Many parts of the world face much larger changes.
The human element
Some climate changes will be unavoidable, because humans have already emitted greenhouse gases into the atmosphere, and the atmosphere and oceans have already been heated.
“There is already some inertia in place,” Diffenbaugh said. “If every new power plant or factory in the world produced zero emissions, we’d still see impact from the existing infrastructure, and from gases already released.”
The more dramatic changes that could occur by the end of the century, however, are not written in stone. There are many human variables at play that could slow the pace and magnitude of change – or accelerate it.
Consider the 2.5 billion people who lack access to modern energy resources. This energy poverty means they lack fundamental benefits for illumination, cooking and transportation, and they’re more susceptible to extreme weather disasters. Increased energy access will improve their quality of life – and in some cases their chances of survival – but will increase global energy consumption and possibly hasten warming.
Diffenbaugh said that the range of climate projections offered in the report can inform decision-makers about the risks that different levels of climate change pose for ecosystems.
“There’s no question that a climate in which every summer is hotter than the hottest of the last 20 years poses real risks for ecosystems across the globe,” Diffenbaugh said. “However, there are opportunities to decrease those risks, while also ensuring access to the benefits of energy consumption.”
From Stanford News: http://news.stanford.edu/news/2013/august/climate-change-speed-080113.html
by Deep Green Resistance News Service | May 12, 2013 | Biodiversity & Habitat Destruction, Climate Change
By University of East Anglia
More than half of common plants and one third of the animals could see a dramatic decline this century due to climate change – according to research from the University of East Anglia.
Research published today in the journal Nature Climate Change looked at 50,000 globally widespread and common species and found that more than one half of the plants and one third of the animals will lose more than half of their climatic range by 2080 if nothing is done to reduce the amount of global warming and slow it down.
This means that geographic ranges of common plants and animals will shrink globally and biodiversity will decline almost everywhere.
Plants, reptiles and particularly amphibians are expected to be at highest risk. Sub-Saharan Africa, Central America, Amazonia and Australia would lose the most species of plants and animals. And a major loss of plant species is projected for North Africa, Central Asia and South-eastern Europe.
But acting quickly to mitigate climate change could reduce losses by 60 per cent and buy an additional 40 years for species to adapt. This is because this mitigation would slow and then stop global temperatures from rising by more than two degrees Celsius relative to pre-industrial times (1765). Without this mitigation, global temperatures could rise by 4 degrees Celsius by 2100.
The study was led by Dr Rachel Warren from theTyndall Centre for Climate Change Research at UEA. Collaborators include Dr Jeremy VanDerWal at James Cook University in Australia and Dr Jeff Price, from UEA’s school of Environmental Sciences and the Tyndall Centre. The research was funded by the Natural Environment Research Council (NERC).
Dr Warren said: “While there has been much research on the effect of climate change on rare and endangered species, little has been known about how an increase in global temperature will affect more common species.
“This broader issue of potential range loss in widespread species is a serious concern as even small declines in these species can significantly disrupt ecosystems.
“Our research predicts that climate change will greatly reduce the diversity of even very common species found in most parts of the world. This loss of global-scale biodiversity would significantly impoverish the biosphere and the ecosystem services it provides.
“We looked at the effect of rising global temperatures, but other symptoms of climate change such as extreme weather events, pests, and diseases mean that our estimates are probably conservative. Animals in particular may decline more as our predictions will be compounded by a loss of food from plants.
“There will also be a knock-on effect for humans because these species are important for things like water and air purification, flood control, nutrient cycling, and eco-tourism.
“The good news is that our research provides crucial new evidence of how swift action to reduce CO2 and other greenhouse gases can prevent the biodiversity loss by reducing the amount of global warming to 2 degrees Celsius rather than 4 degrees. This would also buy time – up to four decades – for plants and animals to adapt to the remaining 2 degrees of climate change.”
The research team quantified the benefits of acting now to mitigate climate change and found that up to 60 per cent of the projected climatic range loss for biodiversity can be avoided.
Dr Warren said: “Prompt and stringent action to reduce greenhouse gas emissions globally would reduce these biodiversity losses by 60 per cent if global emissions peak in 2016, or by 40 per cent if emissions peak in 2030, showing that early action is very beneficial. This will both reduce the amount of climate change and also slow climate change down, making it easier for species and humans to adapt.”
Information on the current distributions of the species used in this research came from the datasets shared online by hundreds of volunteers, scientists and natural history collections through the Global Biodiversity Information Facility (GBIF).
Co-author Dr Jeff Price, also from UEA’s school of Environmental Studies, said: “Without free and open access to massive amounts of data such as those made available online through GBIF, no individual researcher is able to contact every country, every museum, every scientist holding the data and pull it all together. So this research would not be possible without GBIF and its global community of researchers and volunteers who make their data freely available.”
From University of East Anglia: http://www.uea.ac.uk/mac/comm/media/press/2013/May/climate-change-warren-common-species
by Deep Green Resistance News Service | Feb 1, 2013 | Agriculture, Climate Change
By Bangor University
Growing oil palm to make ‘green’ biofuels in the tropics could be accelerating the effects of climate change, say scientists.
Researchers from Bangor University found the creation of oil palm plantations are releasing prehistoric sources of carbon dioxide back into the atmosphere.
The findings throw into doubt hopes that biofuels grown in the tropics could help cut greenhouse gas emissions.
Working as part of an international team, the north Wales scientists looked at how the deforestation of peat-swamps in Malaysia, to make way for oil palm trees, is releasing carbon which has been locked away for thousands of years.
It is feared this carbon will be attacked by microbes and produce the greenhouse gas, carbon dioxide. The Bangor researchers say the ancient carbon comes from deep in the soil, which as the effects of deforestation take hold, breaks down and dissolves into the nearby watercourses.
When describing their work which appears in Nature, Prof Chris Freeman commented: “We first noticed that the ditches draining areas converted to palm oil plantations were loaded with unusually high levels of dissolved carbon back in 1995, but it was not until my researcher Dr Tim Jones took samples to measure the age of that carbon that we realised we were onto something important”. Dr Jones added “We were amazed to discover that the samples from Malaysian oil palm plantations contained the oldest soil-derived dissolved organic carbon ever recorded.”
The Bangor University researchers measured the water leaching from channels in palm oil plantations in the Malaysian peninsular which were originally Peatland Swamp Forest. There are approximately 28,000 km2 of industrial plantations in peninsular Malaysia, Sumatra and Borneo with even more planned, making them a major contributor to peatswamp deforestation in the region. Prof Freeman commented; “Our results are yet another reminder that when we disturb intact peatswamps and convert them to industrial biofuel plantations, we risk adding to the very problem that we are trying to solve”
Prof Freeman added: “We have known for some time that in South East Asia, oil palm plantations were a major threat to biodiversity, including the habitat for orang-utans, and that the drainage could release huge amounts of carbon dioxide during the fires seen there in recent years. But this discovery of a “hidden” new source of problems in the waters draining these peatlands is a reminder that these fragile ecosystems really are in need of conservation.”
Read more from Bangor University: http://www.bangor.ac.uk/news/full.php.en?nid=12106&tnid=12106
by Deep Green Resistance News Service | Jan 19, 2013 | Climate Change
By NASA Jet Propulsion Laboratory
An area of the Amazon rainforest twice the size of California continues to suffer from the effects of a megadrought that began in 2005, finds a new NASA-led study. These results, together with observed recurrences of droughts every few years and associated damage to the forests in southern and western Amazonia in the past decade, suggest these rainforests may be showing the first signs of potential large-scale degradation due to climate change.
An international research team led by Sassan Saatchi of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., analyzed more than a decade of satellite microwave radar data collected between 2000 and 2009 over Amazonia. The observations included measurements of rainfall from NASA’s Tropical Rainfall Measuring Mission and measurements of the moisture content and structure of the forest canopy (top layer) from the Seawinds scatterometer on NASA’s QuikScat spacecraft.
The scientists found that during the summer of 2005, more than 270,000 square miles (700,000 square kilometers, or 70 million hectares) of pristine, old-growth forest in southwestern Amazonia experienced an extensive, severe drought. This megadrought caused widespread changes to the forest canopy that were detectable by satellite. The changes suggest dieback of branches and tree falls, especially among the older, larger, more vulnerable canopy trees that blanket the forest.
While rainfall levels gradually recovered in subsequent years, the damage to the forest canopy persisted all the way to the next major drought, which began in 2010. About half the forest affected by the 2005 drought – an area the size of California – did not recover by the time QuikScat stopped gathering global data in November 2009 and before the start of a more extensive drought in 2010.
“The biggest surprise for us was that the effects appeared to persist for years after the 2005 drought,” said study co-author Yadvinder Malhi of the University of Oxford, United Kingdom. “We had expected the forest canopy to bounce back after a year with a new flush of leaf growth, but the damage appeared to persist right up to the subsequent drought in 2010.”
Recent Amazonian droughts have drawn attention to the vulnerability of tropical forests to climate change. Satellite and ground data have shown an increase in wildfires during drought years and tree die-offs following severe droughts. Until now, there had been no satellite-based assessment of the multi-year impacts of these droughts across all of Amazonia. Large-scale droughts can lead to sustained releases of carbon dioxide from decaying wood, affecting ecosystems and Earth’s carbon cycle.
The researchers attribute the 2005 Amazonian drought to the long-term warming of tropical Atlantic sea surface temperatures. “In effect, the same climate phenomenon that helped form hurricanes Katrina and Rita along U.S. southern coasts in 2005 also likely caused the severe drought in southwest Amazonia,” Saatchi said. “An extreme climate event caused the drought, which subsequently damaged the Amazonian trees.”
Saatchi said such megadroughts can have long-lasting effects on rainforest ecosystems. “Our results suggest that if droughts continue at five- to 10-year intervals or increase in frequency due to climate change, large areas of the Amazon forest are likely to be exposed to persistent effects of droughts and corresponding slow forest recovery,” he said. “This may alter the structure and function of Amazonian rainforest ecosystems.”
The team found that the area affected by the 2005 drought was much larger than scientists had previously predicted. About 30 percent (656,370 square miles, or 1.7 million square kilometers) of the Amazon basin’s total current forest area was affected, with more than five percent of the forest experiencing severe drought conditions. The 2010 drought affected nearly half of the entire Amazon forest, with nearly a fifth of it experiencing severe drought. More than 231,660 square miles (600,000 square kilometers) of the area affected by the 2005 drought were also affected by the 2010 drought. This “double whammy” by successive droughts suggests a potentially long-lasting and widespread effect on forests in southern and western Amazonia.
The drought rate in Amazonia during the past decade is unprecedented over the past century. In addition to the two major droughts in 2005 and 2010, the area has experienced several localized mini-droughts in recent years. Observations from ground stations show that rainfall over the southern Amazon rainforest declined by almost 3.2 percent per year in the period from 1970 to 1998. Climate analyses for the period from 1995 to 2005 show a steady decline in water availability for plants in the region. Together, these data suggest a decade of moderate water stress led up to the 2005 drought, helping trigger the large-scale forest damage seen following the 2005 drought.
Saatchi said the new study sheds new light on a major controversy that existed about how the Amazon forest responded following the 2005 megadrought. Previous studies using conventional optical satellite data produced contradictory results, likely due to the difficulty of correcting the optical data for interference by clouds and other atmospheric conditions.
In contrast, QuikScat’s scatterometer radar was able to see through the clouds and penetrate into the top few meters of vegetation, providing daily measurements of the forest canopy structure and estimates of how much water the forest contains. Areas of drought-damaged forest produced a lower radar signal than the signals collected over healthy forest areas, indicating either that the forest canopy is drier or it is less “rough” due to damage to or the death of canopy trees.
From NASA Jet Propulsion Laboratory: http://www.jpl.nasa.gov/news/news.php?release=2013-025
