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    Mongabay, a leading resource for news and perspectives on environmental and conservation issues related to the tropics, has launched Tropical Conservation Science - a new, open access academic e-journal. It will cover a wide variety of scientific and social studies on tropical ecosystems, their biodiversity and the threats posed to them. Tropical Conservation Science - March 8, 2008.

    At the 148th Meeting of the OPEC Conference, the oil exporting cartel decided to leave its production level unchanged, sending crude prices spiralling to new records (above $104). OPEC "observed that the market is well-supplied, with current commercial oil stocks standing above their five-year average. The Conference further noted, with concern, that the current price environment does not reflect market fundamentals, as crude oil prices are being strongly influenced by the weakness in the US dollar, rising inflation and significant flow of funds into the commodities market." OPEC - March 5, 2008.

    Kyushu University (Japan) is establishing what it says will be the world’s first graduate program in hydrogen energy technologies. The new master’s program for hydrogen engineering is to be offered at the university’s new Ito campus in Fukuoka Prefecture. Lectures will cover such topics as hydrogen energy and developing the fuel cells needed to convert hydrogen into heat or electricity. Of all the renewable pathways to produce hydrogen, bio-hydrogen based on the gasification of biomass is by far both the most efficient, cost-effective and cleanest. Fuel Cell Works - March 3, 2008.

    An entrepreneur in Ivory Coast has developed a project to establish a network of Miscanthus giganteus farms aimed at producing biomass for use in power generation. In a first phase, the goal is to grow the crop on 200 hectares, after which expansion will start. The project is in an advanced stage, but the entrepreneur still seeks partners and investors. The plantation is to be located in an agro-ecological zone qualified as highly suitable for the grass species. Contact us - March 3, 2008.

    A 7.1MW biomass power plant to be built on the Haiwaiian island of Kaua‘i has received approval from the local Planning Commission. The plant, owned and operated by Green Energy Hawaii, will use albizia trees, a hardy species that grows in poor soil on rainfall alone. The renewable power plant will meet 10 percent of the island's energy needs. Kauai World - February 27, 2008.

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Wednesday, September 17, 2008

Scientists: take away global dimming, and global warming will be much worse - "formidable challenges ahead"

The case for carbon-negative bioenergy - capable of actively taking CO2 out of the atmosphere - has become stronger once again, because of a new report showing the need for drastic carbon emissions cuts to counter-balance the disappearance of a phenomenon known as "global dimming", which keeps the planet relatively cool. If the cooling blanket of air pollution - resulting from burning carbon rich fuels - is taken away, then global warming will be more strongly felt and bring greater environmental damage than was previously thought. Therefor, far more ambitious GHG emission reduction targets are needed than the ones currently on the table.

In the new study titled "On avoiding dangerous anthropogenic interference with the climate system: Formidable challenges ahead" the scientists say the earth will warm about 2.4° C (4.3° F) above pre-industrial levels even under extremely conservative greenhouse gas emission scenarios and under the assumption that efforts to clean up particulate pollution continue to be successful. The study, by professor V. Ramanathan from Scripps Atmospheric and Climate Sciences, and co-author Yan Feng, a Scripps postdoctoral research fellow, is published in the online edition of the Proceedings of the National Academy of Sciences.

That amount of warming reported in the new analysis falls within what the world's leading climate change authority recently set as the threshold range of temperature increase that would lead to widespread loss of biodiversity, deglaciation and other adverse consequences in nature. The researchers argue that coping with these circumstances will require "transformational research for guiding the path of future energy consumption."

Ramanathan and Feng assumed a highly optimistic scenario that greenhouse gas concentrations would remain constant at 2005 levels for the next century. For the concentrations to remain at 2005 levels, the emissions of greenhouse gases such as carbon dioxide must decrease drastically within the next decade.

Economic expansion, however, is expected to see emissions increase. The researchers then analyzed expected future warming by assuming that the cooling effect of man-made aerosol pollution will be eliminated during the 21st Century. Currently, particulate air pollution caused by fossil fuel combustion, forest fires and smoke from cooking and agricultural waste burning serves to mask global warming caused by greenhouse gases. The smog does so chiefly by creating a dimming effect at Earth's surface.

But mitigation of this type of pollution has been increasingly successful by countries around the world. Because soot and similar particles remain airborne only for a matter of weeks, it is expected that clean-up efforts produce relatively immediate results. Therefore, the authors based their projections of temperature increase assuming the absence of these pollutants in the atmosphere. By contrast, greenhouse gases can remain in the atmosphere for decades or, in the case of carbon dioxide, more than a century.

This means that if the cooling effect of the air pollution is taken away, the temperature increases resulting from the build up of greenhouse gases are no longer counter-balanced. The warming will persist and be felt more strongly.
This paper demonstrates the major challenges society will have to face in dealing with a problem that now seems unavoidable. We hope that governments will not be forced to consider trade-offs between air pollution abatement and mitigation of greenhouse gas emissions. - Professor V. Ramanathan
Ramanathan and Feng estimated that the increase in greenhouse gases from pre-industrial era levels has already committed Earth to a warming range of 1.4° C to 4.3° C (2.5° F to 7.7° F). About 90 percent of that warming will most likely be experienced in the 21st Century. In 2007, the Intergovernmental Panel on Climate Change identified a temperature increase range between 1° C and 3°C (1.8° F and 5.4°F) as the threshold at which society commits the planet to biodiversity loss and deglaciation in areas such as Greenland and the Himalayas.

The pace at which the world approaches the threshold depends in part on national and international air pollution reduction policies. Despite the masking effects of atmospheric aerosols, the authors note that their removal is still an important objective because of the deleterious human health, agricultural and water supply effects of smog. The authors point out that the real problem is not the reduction of air pollution, but it is the lack of comparable reductions in emissions of CO2 and other greenhouse gases to offset the reductions in the surface cooling effect of the polluting fog:
:: :: :: :: :: :: :: :: :: :: ::

Given that a potentially large warming is already in our rear-view mirror, scientists and engineers must mount a massive effort and develop solutions for adapting to climate change and for mitigating it. - Professor V. Ramanathan
The study implies that most current climate policies - which often take a comfortable target of limiting atmospheric carbon dioxide levels to 450 parts per million (ppm) - are not ambitious enough. Current levels stand at 384ppm. Some climate scientists, like NASA's Dr James Hansen, urge us to aim for a reduction of CO2 levels to 350ppm, to keep the planet liveable (previous post). This goal calls for the large-scale introduction of carbon-negative bioenergy, which is the only way to generate both energy to run societies, while at the same time actively removing carbon dioxide from the atmosphere.

Such radical concepts are needed if we want to counter the effect of taking away the blanket of pollution that keeps us relatively cool.

Scientists like Paul Crutzen have suggested that geo-engineering techniques aimed at creating an artificial 'cooling blanket' - he proposed filling the upper atmosphere with sulphur particles - could counter global warming, if its effects proved to be worse than thought. But then we would be switching from one form of 'cooling' pollution (soot and aerosol particles) to another, far more dangerous one. The potential environmental damages resulting from an idea like Crutzen's have been studied in-depth, and were found to be dramatic. This particular geo-engineering proposal has therefor been quickly dismissed as being too risky (previous post).

Professor V. Ramanathan and Dr Yan Feng's study demonstrates that a deep cut in carbon emissions is the only rational response to the disappearance of the global dimming effect. Carbon-negative bioenergy will play an important role in reducing GHG levels, because it is the most radical of all clean energy technologies. Contrary to ordinary renewables, which are 'merely' carbon-neutral, carbon-negative bioenergy goes beyond zero emissions, by actively removing CO2 from the atmosphere.

The Scripps Institution of Oceanography, at UC San Diego, is one of the oldest, largest and most important centers for global science research and education in the world. The National Research Council has ranked Scripps first in faculty quality among oceanography programs in the U.S. Now in its second century of discovery, the scientific scope of the institution has grown to include biological, physical, chemical, geological, geophysical and atmospheric studies of the earth as a system.

Hundreds of research programs covering a wide range of scientific areas are under way today in 65 countries. The institution has a staff of about 1,300, and annual expenditures of approximately $155 million from federal, state and private sources. Scripps operates one of the largest U.S. academic fleets with four oceanographic research ships and one research platform for worldwide exploration.

Eastern China. Dozens of fires burning on the surface (red dots) and a thick pall of smoke and haze (greyish pixels) filling the skies overhead. This pollution contributes to 'global dimming', which keeps the planet relatively cool. Photo taken by MODIS aboard NASA's Aqua satellite. Credit: Wikimedia.


V. Ramanathan and Y. Feng, "On avoiding dangerous anthropogenic interference with the climate system: Formidable challenges ahead", PNAS published ahead of print, September 17, 2008, doi:10.1073/pnas.0803838105

Biopact: Carbon-negative bioenergy making headway, at last - June 06, 2008

Biopact: Climate change and geoengineering: emulating volcanic eruption too risky - August 15, 2007


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