Showing posts with label carbon dioxide. Show all posts
Showing posts with label carbon dioxide. Show all posts

Monday, March 23, 2009

In world's first global election, vote for Earth

This year, Earth Hour has been transformed into the world’s first global election, between Earth and global warming. For the first time in history, people of all ages, nationalities, race and background have the opportunity to use their light switch as their vote – Switching off your lights is a vote for Earth, or leaving them on is a vote for global warming. WWF are urging the world to VOTE EARTH and reach the target of 1 billion votes, which will be presented to world leaders at the Global Climate Change Conference in Copenhagen 2009. This meeting will determine official government policies to take action against global warming, which will replace the Kyoto Protocol. It is the chance for the people of the world to make their voice heard.

Earth Hour began in Sydney in 2007, when 2.2 million homes and businesses switched off their lights for one hour. In 2008 the message had grown into a global sustainability movement, with 50 million people switching off their lights. Global landmarks such as the Golden Gate Bridge in San Francisco, Rome’s Colosseum, the Sydney Opera House and the Coca Cola billboard in Times Square all stood in darkness.

In 2009, Earth Hour is being taken to the next level, with the goal of 1 billion people switching off their lights as part of a global vote. Unlike any election in history, it is not about what country you’re from, but instead, what planet you’re from. VOTE EARTH is a global call to action for every individual, every business, and every community. A call to stand up and take control over the future of our planet. Over 74 countries and territories have pledged their support to VOTE EARTH during Earth Hour 2009, and this number is growing everyday.

We all have a vote, and every single vote counts. Together we can take control of the future of our planet, for future generations.

On March 28 you can VOTE EARTH by switching off your lights for one hour.
Or you can vote global warming by leaving your lights on.

Thursday, February 19, 2009

Indian experts find bacteria to beat global heat


In a major breakthrough that could help in the fight against global warming, a team of five Indian scientists from four institutes of the country have discovered a naturally occurring bacteria which converts carbon dioxide (CO2) into a compound found in limestone and chalk.

When used as an enzyme — biomolecules that speed up a chemical reaction — the bacteria has been found to transform CO2 into calcium carbonate (CaCO3), which can fetch minerals of economic value, said Dr Anjana Sharma from the biosciences department of RD University, Jabalpur, who was part of the Rs 98.6 lakh project sponsored by the department of biotechnology (DBT) under the Union science and technology ministry.

CO2 is a greenhouse gas produced in the burning of fossil fuels and other industrial activities. The rising emissions of CO2 in the atmosphere is chiefly responsible for global warming. Reducing CO2 levels is the single most important strategy to fight global warming and the resulting effects of climate change.

"The enzyme can be put to work in any situation, like in a chamber fitted inside a factory chimney through which CO2 would pass before being emitted into the atmosphere, and it would convert the greenhouse gas into calcium carbonate,’’ Dr Sadhana Rayalu, the project coordinator who is from the National Environmental Engineering and Research Institute (NEERI), Nagpur, told TOI on phone from Nagpur.

This potentially means that the bacteria — extracted from a number of places including brick kilns in Satna, Madhya Pradesh — can be used to take out CO2 from its sources of emission itself.

Rayalu said the chemical reactions involved in the process have been successfully established while its economic viability, cloning, expression and single-step purification are under study. The team has published its findings in the Indian Journal of Microbiology and its paper has been accepted for publication in the World Journal of Microbiology and Biotechnology.

Sharma said the breakthrough was the result of marathon research work spanning more than three years. Other members of the team are Dr K Krishnamurty from NEERI, Dr T Satyanarayana from Delhi University and Dr A K Tripathi from Banaras Hindu University.

"Interestingly, it is nature that has come to the rescue of the human race from harmful effects of global warming. Investigators of the team have discovered as many as seven such micro-organisms that have the tendency to convert carbon dioxide into calcium carbonate at different natural locations,’’ said Sharma, who was on a visit to Allahabad.

(via Times of India)

Saturday, February 14, 2009

The truth about climate change



The legendary broadcaster and naturalist Sir David Attenborough was long unsure about the causes of the observed climate warming. In his documentary, The Truth About Climate Change, he sheds doubt and explains what convinced him.

Climate models based on purely natural processes such as solar activity and volcanic eruptions fail to explain the observed change in Earth's climate in the latter part of the 20th century. Models factoring in the human impact, that is, the increase of carbon dioxide in the athmosphere, depict the transpired warming accurately, however.

Thursday, February 5, 2009

4 degrees warmer, great cities wash away



Great cities could wash away if the Earth gets hotter by 4 degrees and the Ganges in India could dry up. India would be one of the most impacted countries by global warming.

Saturday, January 3, 2009

The cement that eats carbon dioxide


Cement, a vast source of planet-warming carbon dioxide, could be transformed into a means of stripping the greenhouse gas from the atmosphere, thanks to an innovation from British engineers.

The new environmentally friendly formulation means the cement industry could change from being a "significant emitter to a significant absorber of CO2," says Nikolaos Vlasopoulos, chief scientist at London-based Novacem, whose invention has garnered support and funding from industry and environmentalists.

The new cement, which uses a different raw material, certainly has a vast potential market. Making the 2bn tonnes of cement used globally every year pumps out 5% of the world's CO2 emissions - more than the entire aviation industry. And the long-term trends are upwards: a recent report by the French bank Credit Agricole estimated that, by 2020, demand for cement will increase by 50% compared to today.

Making traditional cement results in greenhouse gas emissions from two sources: it requires intense heat, and so a lot of energy to heat up the ovens that cook the raw material, such as limestone. That then releases further CO2 as it burns. But, until now, noone has found a large-scale way to tackle this fundamental problem.

Novacem's cement, based on magnesium silicates, not only requires much less heating, it also absorbs large amounts of CO2 as it hardens, making it carbon negative. Set up by Vlasopoulos and his colleagues at Imperial College London, Novacem has already attracted the attention of major construction companies such as Rio Tinto Minerals, WSP Group and Laing O'Rourke, and investors including the Carbon Trust.

The company has just started a £1.5m project funded by the government-backed Technology Strategy Board to build a pilot plant. If all goes well, Vlasopoulos expects to have Novacem products on the market within five years.

Jonathan Essex, a civil engineer at the building consultancy Bioregional who also sits on the environment and sustainability panel for the Institution of Civil Engineers, welcomed Novacem's ideas to tackle the carbon impact of cement. "In the UK the climate bill commits us to reduce CO2 emissions, and every sector should play its part. The construction industry needs to take greater responsibility for its own environmental impact." Essex said that, if Novacem can make their cement at a competitive price, the next step could be to take even more CO2 emissions out of the process by using renewable energy to fire the furnaces.

According to Novacem, its product can absorb, over its lifecycle, around 0.6 tonnes of CO2 per tonne of cement. This compares to carbon emissions of about 0.4 tonnes per of standard cement. "From that point of view, it's attractive," said Rachael Nutter, head of business incubators at the Carbon Trust. "The real challenge is what is the supply chain, who do you need to partner with to take it to market? The million-dollar question is what are the applications of it? If it ends up as decorative applications such as floor tiles, it's quite interesting but not as much as if you get into load-bearing structural stuff."

Previous attempts to make cement greener have included adding more aggregate to a concrete mixture, thereby using less cement. But this still does not tackle the problem of the carbon emissions from making the cement in the first place. Other systems use polymers in the mix, but none have yet made a significant impact on the market.

A spokesperson for the British Cement Association expressed a sceptical note, saying that though there was much ongoing laboratory work on new types of cement, there were also problems. "The reality is that the geological availability, and global distribution, of suitable natural resources, coupled with the extensive validation needed to confirm fitness-for-purpose, make it highly unlikely that these cements will a be realistic alternative for volume building."

Vlasopoulos responded that magnesium silicates are abundant worldwide, with 10,000 billion tonnes available, according to some estimates. "In addition, the production process of our cement is of a chemical nature, which means it can also utilise various industrial byproducts containing magnesium in its composition." He is confident the material will be strong enough for use in buildings but acknowledged that getting licenses to use it will take several years of testing.

Explainer: Ecofriendly vs traditional cement

Standard cement, also known as Portland cement, is made by heating limestone or clay to around 1,500C. The processing of the ingredients releases 0.8 tonnes of CO2 per tonne of cement. When it is eventually mixed with water for use in a building, each tonne of cement can absorb up to 0.4 tonnes of CO2, but that still leaves an overall carbon footprint per tonne of 0.4 tonnes.

Novacem's cement, which has a patent pending on it, uses magnesium silicates which emit no CO2 when heated. Its production process also runs at much lower temperatures - around 650C. This leads to total CO2 emissions of up to 0.5 tonnes of CO2 per tonne of cement produced. But the Novacem cement formula absorb far more CO2 as it hardens - about 1.1 tonnes. So the overall carbon footprint is negative - ie the cement removes 0.6 tonnes of CO2 per tonne used.

(via The Guardian.)


Friday, November 28, 2008

Al Gore debates global warming

Al Gore debates expert climatologists on whether carbon dioxide causes global warming.