IPCC: Vrees voor forse stijging temperatuur

Klimaatdeskundigen sluiten niet uit dat de temperatuur deze eeuw met 6 graden of meer stijgt. Een stijging tussen 2 en 4,5 graden tot 2100 is in ieder geval hoogstwaarschijnlijk.

De berekeningen van de honderden topwetenschappers voor de Verenigde Naties staan in een ontwerprapport, waarvan de definitieve versie vrijdag in Parijs moet worden gepubliceerd. De Britse krant The Independent publiceerde maandag al conclusies uit het concept.

De deskundigen buigen zich deze week op een conferentie van de VN in de Franse hoofdstad over de gevolgen van het broeikaseffect. In het vorige verslag uit 2001 spraken de wetenschappers al de verwachting uit dat de temperatuur met 1,4 tot 5,8 graden zou kunnen toenemen.

De verwachtingen over de stijging van de zeespiegel lagen zes jaar geleden bij 9 tot 88 centimeter. Inmiddels gaan de deskundigen uit van een gemiddeld 43 centimeter hogere zeespiegel in 2100, zelfs als de hoeveelheid kooldioxide in de atmosfeer wordt gestabiliseerd. Kooldioxide geldt als een van de hoofdoorzaken van het broeikaseffect.

Bron: www.nu.nl

Communicatie over klimaatonderzoek

"Hoe gaat het in de praktijk als je wetenschappelijk ambtenaar bent en geacht wordt de minister en haar beleid te dienen? In het juni-nummer van Meteorologica liet Huug van de Dool ons in de keuken van de Amerikaanse ambtenaren kijken. In dit artikel zal ik op verzoek van de redactie iets over mijn ervaringen vertellen, als Directeur Klimaatonderzoek en Seismologie van het KNMI en als Nederlands vertegenwoordiger bij het IPCC."

Lees verder...

The Footprint of a Cheeseburger

"Based on a variety of sources, the researchers conclude that the total energy use going into a single cheeseburger amounts to somewhere between about 7 and 20 megajoules -- the range comes from the variety of methods available to the food industry.

The researchers break this down by process, but not by energy type. Here, then, is my first approximation: I split the food production and transportation uses into a diesel category, and the food processing (milling, cooking, storage) uses into an electricity category. Split this way, the totals add up thusly:

Diesel -- 4.7 to 10.8 MJ per burger
Electricity -- 2.6 to 8.4 MJ per burger

With these ranges in hand, I could then convert the energy use into carbon emissions, based on fuel. For electricity, I calculated the footprint using both natural gas and coal; if you're lucky enough to have your local burger joint powered by a wind farm, you can drop that part of the footprint entirely.

Diesel -- 90 to 217 grams of carbon per burger
Gas -- 37 to 119 grams of carbon per burger
Coal -- 65 to 209 grams of carbon per burger

...for a combined carbon footprint of a cheeseburger of 127 grams of carbon (at the low end, with gas) to 426 grams of carbon (at the high end, with coal). Adding in the carbon from operating the restaurant (and driving to the burger shop in the first place), we can reasonably call it somewhere between a quarter-kilogram and a half-kilogram of carbon emissions per cheeseburger."

Source: www.greenbiz.com

India and China in warming study

"India and China have agreed to send an expedition to the Himalayas to study the impact that global warming is having on glaciers there.
They fear that melting glaciers could threaten rivers which support the lives of millions of people.

Scientists and mountaineers from the two countries are now planning to head for the source of two rivers."

Source: www.bbc.co.uk & www.cnn.com

Huge ice shelf breaks free in Canada's far north

"A chunk of ice bigger than the area of Manhattan broke from an ice shelf in Canada's far north and could wreak havoc if it starts to float westward toward oil-drilling regions and shipping lanes next summer, a researcher said on Friday.

Global warming could be one cause of the break of the Ayles Ice Shelf at Ellesmere Island, which occurred in the summer of 2005 but was only detected recently by satellite photos, said Luke Copland, assistant professor at the University of Ottawa's geography department.

It was the largest such break in nearly three decades, casting an ice floe with an area of 66 square km (25 square miles) adrift in the Arctic Ocean, said Copland, who specializes in the study of glaciers and ice masses. Manhattan has an area of 61 square km (24 square miles).

The mass is now 50 square km (19 square miles) in size.

"The Arctic is all frozen up for the winter and it's stuck in the sea ice about 50 km (30 miles) off the coast," he said.

"The risk is that next summer, as that sea ice melts, this large ice island can then move itself around off the coast and one potential path for it is to make its way westward toward the Beaufort Sea, and the Beaufort Sea is where there is lots of oil and gas exploration, oil rigs and shipping.""

Source: www.reuters.com

Imagine Earth without people

"15,589 Number of species threatened with extinction"
Now just suppose they got their wish. Imagine that all the people on Earth - all 6.5 billion of us and counting - could be spirited away tomorrow, transported to a re-education camp in a far-off galaxy. (Let's not invoke the mother of all plagues to wipe us out, if only to avoid complications from all the corpses). Left once more to its own devices, Nature would begin to reclaim the planet, as fields and pastures reverted to prairies and forest, the air and water cleansed themselves of pollutants, and roads and cities crumbled back to dust.

"The sad truth is, once the humans get out of the picture, the outlook starts to get a lot better," says John Orrock, a conservation biologist at the National Center for Ecological Analysis and Synthesis in Santa Barbara, California. But would the footprint of humanity ever fade away completely, or have we so altered the Earth that even a million years from now a visitor would know that an industrial society once ruled the planet?"

Great story, and in the top 13 of most interesting new scientist stories of 2006.

Source: www.newscientist.com