Green Roofs & Global Greenhouse Cities

Green Roofs Australia held their national conference in Melbourne this week and President Sidonie Carpenter announced the hosting of the 2012 Cities Alive Australia World Green Infrastructure Congress in Brisbane. More on how global cities are reducing greenhouse gas emissions and the role of green roofing.

Green Roofs Australia Inc (GRA Inc) is the host of the 2012 Cities Alive Australia World Green Infrastructure Congress from 12 – 20 October. Global owner of this annual event is the Toronto, Canada-based Green Roofs Infrastructure Network (WGRIN). GRA Inc is one of 12 national associations that are now WGRIN members.

The Brisbane-led congress is being planned with four major themes for papers and displays on green roofs, green walls and allied technologies.  The focus will be on the HOT-DRY green roof and green wall technology considered essential for future responses to many of the world’s climate change problems and transport cost problems.  A call for papers and displays is now open.

The first week of the congress will be held in the Brisbane Convention and Exhibition Centre, Southbank.

Source: www.greenroofs.wordpress.com

American Chemical Society: Global cities and greenhouse gas emissions

Denver released the largest amount of greenhouse gases (GHG) and Barcelona the smallest amount in a new study documenting how differences in climate, population density and other factors affect GHG emissions in global cities. The study, which could identify ways in which cities can reduce GHG emissions, is scheduled for October 1 issue of ACS’ Environmental Science & Technology, a semi-monthly journal.

Christopher Kennedy and colleagues note in the new study that some cities are developing strategies to reduce releases of GHG, which include carbon dioxide, methane, and other gases that can contribute to global warming through the greenhouse effect. Not enough information was previously available on why emissions vary considerably among different cities. The authors asked, “How and why do emissions differ between cities?”

To help answer those questions, the scientists analyzed those variations and how climate, power generation, transportation, waste processing, and other factors contributed to the differences. Denver had the highest overall GHG emissions, with levels two to five times higher than other cities. Its high levels were due partly to its high use of electricity, heating and industrial fuels, and ground transportation, they note. Los Angeles was second on the list, followed by Toronto and Cape Town (tied for third), Bangkok, New York City, London, Prague, Geneva, and Barcelona.

‘Green’ roofs may help put lid on global warming

“Green” roofs, those increasingly popular urban rooftops covered with plants, could help fight global warming, scientists in Michigan are reporting. The scientists found that replacing traditional roofing materials in an urban area the size of Detroit, with a population of about one-million, with green would be equivalent to eliminating a year’s worth of carbon dioxide emitted by 10,000 mid-sized SUVs and trucks. Their study, the first of its kind to examine the ability of green roofs to sequester carbon which may impact climate change, is scheduled for the Oct. 1 issue of ACS’ Environmental Science & Technology, a semi-monthly journal.

Kristin Getter and colleagues point out in the new study that green roofs are multi-functional. They reduce heating and air conditioning costs, for instance, and retain and detain stormwater. Researchers knew that green roofs also absorb carbon dioxide, a major greenhouse gas that contributes to global warming, but nobody had measured the impact until now.

The scientists measured carbon levels in plant and soil samples collected from 13 green roofs in Michigan and Maryland over a two-year period. They found that green roofing an urban area of about one million people would capture more than 55,000 tons of carbon, the scientists say. That’s an amount “similar to removing more than 10,000 mid-sized SUV or trucks off the road a year,” the article notes.

Source: www.eurekalert.org