Global Rivers Emit Three Times IPCC Estimates of Greenhouse Gas Nitrous Oxide

ScienceDaily (Dec. 27, 2010) — What goes in must come out, a truism that now may be applied to global river networks. Human-caused nitrogen loading to river networks is a potentially important source of nitrous oxide emission to the atmosphere. Nitrous oxide is a potent greenhouse gas that contributes to climate change and stratospheric ozone destruction.

It happens via a microbial process called denitrification, which converts nitrogen to nitrous oxide and an inert gas called dinitrogen.

When summed across the globe, scientists report this week in the journal Proceedings of the National Academy of Sciences (PNAS), river and stream networks are the source of at least 10 percent of human-caused nitrous oxide emissions to the atmosphere.

That's three times the amount estimated by the Intergovernmental Panel on Climate Change (IPCC).
Rates of nitrous oxide production via denitrification in small streams increase with nitrate concentrations.
"Human activities, including fossil fuel combustion and intensive agriculture, have increased the availability of nitrogen in the environment," says Jake Beaulieu of the University of Notre Dame and the U.S. Environmental Protection Agency in Cincinnati, Ohio, and lead author of the PNAS paper.

"Much of this nitrogen is transported into river and stream networks," he says, "where it may be converted to nitrous oxide, a potent greenhouse gas, via the activity of microbes."

Beaulieu and co-authors measured nitrous oxide production rates from denitrification in 72 streams draining multiple land-use types across the United States. Their work was part of a broader cross-site study of nitrogen processing in streams.

"This multi-site experiment clearly establishes streams and rivers as important sources of nitrous oxide," says Henry Gholz, program director in NSF's Division of Environmental Biology, which funded the research.
"This is especially the case for those draining nitrogen-enriched urbanized and agricultural watersheds, highlighting the importance of managing nitrogen before it reaches open water," Gholz says. "This new global emission estimate is startling."

Atmospheric nitrous oxide concentration has increased by some 20 percent over the past century, and continues to rise at a rate of about 0.2 to 0.3 percent per year.

Beaulieu and colleagues, say the global warming potential of nitrous oxide is 300-fold greater than carbon dioxide.

Nitrous oxide accounts for some six percent of human-induced climate change, scientists estimate.

Source:  sciencedaily.com

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The Climate War

The climate change rhetoric when Obama came to power was exciting. It sounded as if he would lead from the front and the US would soon have a federal cap-and-trade system. “Delay is not longer an option. Denial is no longer an acceptable response.”  Certainly we have seen an end to denial from the White House. But we are still waiting for an end to delay, and increasingly it looks as if we’ll be waiting for a long time. Why?

Eric Pooley’s   book The Climate War: True Believers, Power Brokers, and the Fight to Save the Earth sheds a good deal of light on why it is that America, in spite of all the scientific evidence that demonstrates the threatening reality of climate change, is still unable, and often unwilling, to mobilise itself to address the danger.

The author is an accomplished journalist who has spent hundreds of hours over the past three years interviewing some of the players in America’s painfully slow progress towards climate change legislation.  The result is an illuminating story of battles in an ongoing war which is far from conclusion. It’s told painstakingly but with a narrative verve that carries the reader along irresistibly through its mass of detailed accounts. It’s compelling reading, from which I’ll mention just a few examples.

The Environmental Defense Fund   (EDF) is the climate change group to which Pooley devotes most of his attention. A large organisation which has been at work for over 40 years, the EDF has long argued for a cap and trade system to tackle CO₂ emissions. Its president, Fred Krupp, is focused on partnership with business to bring about political action on climate change and was influential in the formation of the US Climate Action Partnership   (USCAP) in 2007, initially a group of ten companies and four environmental groups.

Among them was Jim Rogers  , CEO of Duke Energy. In typically detailed fashion Pooley recreates the drama of meetings at which were hammered out the conditions on which Rogers felt he could join the Call for Action USCAP planned to issue. It hinged on whether allowance was made for initial free distribution of allowances to utilities like Duke, a sticking point for Rogers.

USCAP may have been looked at askance by many Green groups, but Roger’s involvement didn’t go down well with his colleagues at the Edison Electric Institute   either. He was chairman at the time and several CEOs called for him to step down. At the Heartland Institute denier’s convention in 2008 Steven Milloy bitterly expressed his dismay that CEOs would endorse a mandatory cap. “What do you do when the people who represent business and free enterprise have switched sides on you?”

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Rising Sea Levels: Environmental Impact

This is an article  on the effects of rising sea levels. In this article, I discuss the ways in which rising tides can decimate local ecosystems and the environment.

One of the most discussed effects of global warming is the increased rate of sea level rise. The rise is due primarily to higher temperatures, which effect sea levels in two ways. First, if temperatures rise, water gets hotter, causing it to expand. Second, the heat melts ice sheets, caps, and glaciers, causing meltwater to flow into the oceans. In a previous article, I discussed the impact of sea level rise on humans; in this article, I will discuss the impact on the environment.

Land Loss

Coastal wetlands are key ecosystems in the biosphere. They support a combination of oceanic species and land species- everything from seagulls to striped bass. They form a “transition zone”, where salt and freshwater fish species like the trout can pass from rivers and streams to the sea. However, rising sea levels are threatening these key habitats. As ocean levels rise, erosion occurs on the shore. As wetlands depend on solid ground for cattails and other aquatic plants to grow, the removal of earth can be devastating. Researchers suggest that by 2080 almost 33% of wetlands will be converted into open water.

Water Salinity

Most aquatic animal and plant species are highly sensitive to salinity levels in their water. As sea levels rise, they flood low-lying freshwater marshes and lakes, making them partially saline. This can kill and damage many native species. The Florida Everglades, for example, are in danger of become salty due to the encroachment of the Atlantic ocean. This would devastate the rich plant and animal life of the Everglades.

Storms

Rising sea levels increase the intensity of storms and floods throughout the world. In high-risk areas like Southeast Asia and Australia, floods could decimate much of the inland plant and animal population. Most ground and burrowing animals, for example, could drown in their dens. Australian researchers have modeled the effects of floods in the future and have discovered that, with the current rate of sea level rise, a storm that now floods 32 square kilometers will flood 71 square kilometers by 2050.

So even though sea levels rise only a few millimeters per year, they can have disastrous effects on world ecosystems. It shows just how sensitive nature is- the smallest change can make a world of difference.

More Information

http://www.smh.com.au/news/environment/effects-of-sealevel-rise-only-just-beginning/2007/10/02/1191091115328.html

http://www.epa.gov/climatechange/effects/coastal/index.html

http://environment.about.com/od/greenhouseeffect/a/rising_sea_leve.htm

The Clean Industrial Revolution

The problem with cutting greenhouse gas emissions is that it will harm economic growth. Right? No, quite the opposite, says Ben McNeil in his book The Clean Industrial Revolution. It’s an age-old myth that doing good for the environment is bad for the economy. He’s addressing Australians, but what he has to say will arrest readers from many countries.

McNeil is a senior research fellow at the Climate Change Research Centre at the University of New South Wales. Besides a PhD in climate science he also holds a Master of Economics degree. The two worlds are bridged in this energetic book. Australia is very vulnerable to climate change through sea-level rise, rainfall changes, storms, and a decrease in food production. It is also highly carbon-intensive in its economy and its export industries will suffer as a consequence when the world starts to move heavily to reduce carbon emissions and impose carbon tariffs.

Such consequences can be pre-empted by a clean-energy revolution, one for which Australia is well-endowed. That hot arid interior is the potential source of vast quantities of high capacity solar power. The use of mirrors to concentrate sunlight so perfectly that the ultra-high temperatures convert water to steam is one way. Another, already under construction in north-west Victoria, uses mirrors to concentrate the sunlight on to high-performance photovoltaic panels. Solar power could replace the need for coal-fired power stations.

A massive underground “hot rock” heat source can be tapped to create steam for power generation, a technique already being worked on by a number of companies at several sites throughout Australia. Wind power in the south could supply 20 percent of the country’s needs. Advanced biofuels that do not impact on food can be produced. Biomass-fuelled electricity is already produced in some parts of rural Australia. Carbon capture and storage may hold some hope for the continuing use of coal, though not while coal companies put a miserly 0.3 percent of their production value into research, apparently believing that governments will do the work for them.

McNeil argues that Australia must take up a forefront position in the low-carbon economic future if it wants to remain prosperous. At the time of writing in 2009 he expected the emissions trading scheme to kick in, putting a price on carbon and pointing the economy towards investment in clean energy. This has been delayed, but even without it there is ample reason for the change of focus away from the carbon-intensive economy (carbon obesity he calls it). The world will soon be crying out for clean energy technology. Australia will continue to prosper in the future if it has used research and development to drive down the cost of renewable energy technologies, and investment to commercialise them and prepare them for export.

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