Drought in Amazon raised severe concerns

It is unusual but sometimes happens for the rain forests to have no rain.

In 2005 the severe drought hit Amazon rain forest, the rivers level fell dramatically and according to the scientists these could happen ones in a century or so.

But an expectantly last year drought affected Amazon region in much larger area than in 2005, so the scientist are concern that these could become a pattern and that it is more than a coincides.

Although the cause is still unknown, it could be natural climatic variations and in the future we might see no more of these types of droughts, but the alternative is that it is associated with high concentration of greenhouse gases in the atmosphere, Dr. Simon Lewis explained for BBC News.

Rain forests like Amazon are natural absorbers of CO2 and by losing their ability and capacity to absorb; more greenhouse gases are ending in the atmosphere.

According to a research published in journal Science, in a typical year the forest absorbs 1.5 bn tonnes CO2, but in the 2005 the forest released 5 bn tonnes CO2, because of a dying trees. 

The real concern comes if we just compare the last year’s figures of released 8 bn tonnes from the forest and 5.4 bn tonnes CO2  produced by US  in 2009 by burning fossil fuels.

It is our duty to protect the forests by any cost.

Written by: Jasmina Nikoloska
Source: www.bbc.co.uk

What's the carbon footprint of ... building a house

New homes require far less energy to run than older properties, but building them generates plenty of CO2

• More carbon footprints: the internet, cycling a mile, others
• Understand more about carbon footprints

 

New houses such as these ones in south Derbyshire take lots of energy and resources to produce. Photograph: Rui Vieira/PA

 

The carbon footprint of a house:
80 tonnes CO2e: A newbuild two-bed cottage

The carbon footprint of building a house depends on all kinds of things – including, of course, the size of the house and the types of materials chosen.

The estimate of 80 tonnes given above is for the construction of a brand-new cottage with two bedrooms upstairs and two reception rooms and a kitchen downstairs. It's based on a study that I was involved in for Historic Scotland.
The study looked at the climate change implications of various options for a traditional cottage in Dumfries: leave it as it is, refurbish, or knock it down and build a new one to various different building codes. We looked at the climate change impact over a 100-year period, taking into account the embodied emissions in the construction and maintenance as well as the energy used and generated by those living in the building.

Unsurprisingly, the worst option by far was to do nothing and leave the old house leaking energy like a sieve. Knocking down and starting again worked out at about 80 tonnes CO2e whether the house was built to 2008 Scottish building regulations or to the much more stringent and expensive Code for Sustainable Homes Level 5 that demanded 'carbon neutrality'.

Here's how that total broke down for the carbon-neutral option:

• Walls 60%
• Timber 14%
• Pipework and drainage 9%
• Floors 5%
• Slate roof 5%
• Photovoltaic panels 3%
• Other 4%

Eighty tonnes is a lot – equivalent to five brand-new family cars, about six years of living for the average Brit or 24 economy-class trips to Hong Kong from London. But a house may last for a century or more, so the annual carbon cost is much less – and for all the new-build options, the up-front emissions from construction work were paid back by savings from better energy efficiency in 15–20 years.

However, the winning option was to refurbish the old house, because the carbon investment of doing this was just eight tonnes CO2e, and even the highest-specification newbuild could not catch up this advantage over the 100-year period. Once cost was taken into account, refurbishment became dramatically the most practical and attractive option, too.

If this one study is representative, the message for the construction industry is clear. Investment in the very highest levels of energy-efficiency for new homes is, even at its best, an extremely costly way of saving carbon. Investing in improvements to existing homes is dramatically more cost-effective.

See more carbon footprints.

• This article draws on text from How Bad Are Bananas? The Carbon Footprint of Everything by Mike Berners-Lee

www.guardian.co.uk

Pollution is not the reason of temperature drop in Northern Hemisphere around 1970

The new research, led by Dave Thompson from Colorado State University in Fort Collins, US, shows that the top layers of Northern Hemisphere water cooled by about 0.3C between 1968 and 1972, while the South Hemisphere saw approximately the same degree of warming.

But the timescale of the drop is much shorter, than that previously linked to the increasing sulphate aerosols from fossil fuel in the troposphere, or changes in the climate of the world’s oceans that evolve over decades (oscillatory multidecadal variability).

Photo: ijolumoet.com

This research suggests that the explanation of the cooling could lie somewhere else, it is not clear where, since the effect of aerosols is expected to be more gradually.

A model developed by Thompson which uses data collected by ships and buoys over the past two and a half centuries examined temperature change on a month-by-month basis, unlike previous studies that look at temperature change on a decadal scale.

The team fed the data into a model that blocks out short-term changes in ocean temperature – triggered, for example, by volcanic eruptions which spew sulphur aerosols into the atmosphere. This allowed them to identify changes in ocean temperature that weren't linked to natural variation; The Guardian wrote on 22 September 2010.

It is unclear what caused the cooling process, but an unusually large discharge of ice from the Arctic Ocean in 1967 is the reason of a 10,000 cubic kilometre pool of fresh water from the coast of Greenland, which appears to have lowered the salinity of water in the North Atlantic, according to Mark Maslin of the Environment Institute at University College London.

One possibility is the Great Salinity Anomaly (GSA) which presumably interrupted the mixing process of cooled surface water and warm deep water that caused a cool period by dumping light, fresh water on the surface.

Still, it is a fact that currently greenhouse gases are warming up the Planet.


Written by Jasmina Nikoloska
Sources: Abstract of the paper in Journal Nature

               The Guardian

Global warming could cut number of Arctic hurricanes, study finds

Research says storms that hamper the exploitation of Arctic reserves may halve by 2100, but experts warn against oil rush.

Photo: treehugger.com
A reduction in storms may open up some Arctic regions, but they would simply move to other areas.

Global warming could halve the frequency of Arctic hurricanes – extreme storms that strike the north Atlantic during winter – by 2100, according to a new study, potentially encouraging exploitation of the region's oil reserves.

"Our results provide a rare example of climate change driving a decline in extreme weather, rather than an increase," says Matthias Zahn at the University of Reading. His study, published in the Nature journal, is the first to use a global climate model to assess how Arctic hurricanes may behave in a warmer world.

The results of his study may provide encouragement to to oil and gas companies that currently consider drilling in the northern north Atlantic very risky he says. "As the likelihood of hurricanes destroying oil rigs declines, drilling in the region may become a more attractive option.".

Arctic hurricanes, also known as polar lows, are explosive storms that develop and die over a few days. They form when…

See more: http://www.guardian.co.uk/environment/2010/sep/16/global-warming-arctic-hurricanes-oil 

Could CO2 become the car fuel of the future?

The University of Bath, the University of Bristol and the University of West of England recently received £1.4 million in funding from the Engineering & Physical Sciences Research Council (EPSRC) to develop a method to capture atmospheric CO2 and transform it into fuel that will power cars in the future.

 The team of scientists includes chemists, chemical engineers, biologists and life-cycle analysts who will work together on the creation of an innovative technology that will absorb carbon dioxide from the air and then convert it, chemically, to a state that would permit fuel to be produced from it.

Such would be an effective system for reducing carbon emissions and providing a green car fuel alternative, eliminating the need for additional fossil fuels, oil, coal and natural gas.

This, however, is not an unknown process, as in nature, trees and algae uses CO₂ in unlocking the chemical energy inside their molecules to power metabolic processes.

The idea here is to convert CO₂ into carbon monoxide (CO) by removing one of the oxygen atoms. After obtaining CO, the process of producing hydrocarbon fuels, such as petrol, is much simpler.
But the subsequent conversion of CO₂ into fuel requires a lot of energy – the key challenge is to find an efficient way of doing it.

Researchers are trying to develop porous materials that could absorb CO₂ from the air. These porous materials would be part of the factory’s chimneys, which would absorb carbon dioxide and ultimately reduce the effects of climate change.

See more: http://www.energetika.net/eu/novice/articles/could-co2-become-the-car-fuel-of-the-future