Tuesday 7 September 2010

The Story So Far....

Landsat image of the Pine Island Glacier ice s...Image via Wikipedia
A few notes from watching the videos and reading the articles previously posted.
25 years of satellite data looking at atmospheric temperature shows no significant rise, according to the documentary "Doomsday Called Off". Similar results are seen in data from weather balloons over the same period. Other articles show a global temperature rise, using the same data.
The sea level around the Maldives has fallen between 20 to 30cm since the 1970s, due to increased evaporation.
The East Antarctic ice sheet is growing  due to increased precipitation.
Increased meltwater from Antartica's Pine Island Glacier may be due more to changing sea-bed conditions than to temperature. An undersea ridge appears to have been ground away, and this allows relatively warner seawater greater access to the underside of the glacier....

More on the Maldives:

Professor Niels-Axel Mörner, a leading world authority on sea levels and coastal erosion who headed the Department of Paleogeophysics & Geodynamics at Stockholm University:
The Maldives like other low-lying areas have been condemned by IPCC to become flooded in 50-100 years. The INQUA Commission on Sea Level Changes and Coastal Evolution (the international organisation that hosts the true world specialists on sea level changes) have studied the actual sea level changes in the Maldives and hope to be able to extend the studies to other parts of SE Asia. Our findings reveal that there is no reality behind the scenario of a recent future flooding. The sea level has not been rising in the Maldives in the last centuries and at around 1970 it even experienced a significant lowering. The models of IPCC are simply over-ruled by the theory and observation by sea level specialists within INQUA. We should all be happy about this, one would assume. This is not the case, however. The government of the Maldives has put much prestige in the fear of a future flooding, accusing the west of having caused this situation and demanding them to pay for it. Without a flooding scenario, they now fear that international aid might be cancelled. In this situation, our scientific studies in the Maldives are regarded as anti-governmental and we are now working under very complicated conditions. For the people of the Maldives it is a great relief not to live under a constant threat that all will be gone in one or two generations. For science it is necessary to be able to go on recording the true story and not having to rely on absurd models not anchored in field observations. For a poor country like the Maldives they should always be entitled to become assisted by countries in the west. Furthermore, a coastal country like the Maldives is always threatened by coastal events (storms, hurricanes, tsunamis, etc) that may have disastrous effects on a short-term scale.



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Global Warming - Doomsday Called Off (1/5)

Climate data Information

Relationship of Earth's orbit to periods of gl...Image via Wikipedia
http://www.climatedata.info
A lot of data on climate and climate change are available on the internet but they are not presented in a way which makes them easy to understand. Where climate data are available in a digestible form they are often being used to support one side or the other of highly polarised positions. We are trying to prove only one thing: rational debate is possible when participants have access to the facts. On this site you will find graphs, explanation and data related to essential aspects of climate change. Everything can be downloaded for free and the data files can be input directly to spreadsheets on Windows, Macintosh and UNIX operating systems.
 The climate information and data are available in the following subject areas:
* Temperature - observed and climate model simulations of Global, European and American temperature.
* Precipitation - observed and climate model simulations of Global, European and American precipitation.
* Greenhouse Gases - variation of CO2 and methane over time and a break-down of CO2 by source and geographical origin; the influence of greenhouse gases on climate.
* Proxy data: (i) Ice Cores - Antarctic, Arctic and glaciers with temperature and other data for 100s of thousands of years. (ii) Tree Rings - data from northern and southern hemisphere countries with temperature estimates for 100s of years.
* Natural Climate Forcing - albedo (reflectivity) of earth; orbital variations (Milankovitch cycles) ; sun-spots; El Niňo and other oscillations; radio-sonde temperature profiles.
* Climate Impacts - Global sea level; snow cover, Arctic and Antarctic sea ice; tropical cyclones; polar bears.
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Indian Ocean sea-level rise threatens coastal areas | Science Blog

Indian Ocean sea-level rise threatens coastal areas | Science Blog
While several areas in the Indian Ocean region are experiencing sea-level rise, sea level is lowering in other areas. The study indicated that the Seychelles Islands and Zanzibar off Tanzania’s coastline show the largest sea level drop.

“Global sea-level patterns are not geographically uniform,” says NCAR scientist Gerald Meehl, a co-author of the paper. “Sea-level rise in some areas correlates with sea-level fall in other areas.”




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Estimation of sea level change

Sea level has been rising cm/year, based on me...Image via Wikipedia

Estimation of sea level change
Global sea levels have traditionally been estimated from tide gauges. As can be imagined they show fluctuations of several meters due to tide and wave action. Identifying sea level changes of a few millimetres a year against this background “noise” is problematic. Since 1993, data are available from satellites. There are two other factors which add to the difficulty of estimate changes in sea level. The first is the way the earth has reacted to the melting of the ice caps. Where major ice melt has taken place, in northern Europe and North America for example, land levels have risen; the post glacial rebound (PGR). Conversely where sea levels have risen and encroached on previously dry areas, land levels have fallen; glacial isostatic adjustment (GIA). (Some sources use the two terms interchangeably) These changes typically average around 4 mm/decade but can be higher in some locations. The second factor is the influence of atmospheric pressure. The changes in pressure can be seasonal and modify levels by 1 metre; often an allowance is made for these pressure difference by applying what is called “an inverted barometer.” As can be seen the adjustments to be made to sea level are of a similar order of magnitude to change in sea level itself. It is generally considered that the rate of change of sea level cannot be accurately estimated for periods of less than 10 years.
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Diesels greener than battery cars, says Swiss gov report • The Register

Diesels greener than battery cars, says Swiss gov report • The Register
Swiss boffins have mounted an investigation into the largely unknown environmental burdens of electric cars using lithium-ion batteries, and say that the manufacturing and disposal of batteries presents no insurmountable barriers to electric motoring. However, their analysis reveals that modern diesel cars are actually better for the environment than battery ones.

The revelations come in a new report issued by Swiss government research lab EMPA, titled Contribution of Li-Ion Batteries to the Environmental Impact of Electric Vehicles. The Swiss boffins, having done some major research into the environmental burdens of making and disposing of li-ion batteries - to add to the established bodies of work on existing cars - say that battery manufacture and disposal aren't that big a deal. However, in today's world, with electricity often made by burning coal or gas, a battery car is still a noticeable eco burden:

The main finding of this study is that the impact of a Li-ion battery used in [a battery-powered car] for transport service is relatively small. In contrast, it is the operation phase that remains the dominant contributor to the environmental burden caused by transport service as long as the electricity for the [battery car] is not produced by renewable hydropower ...

A break even analysis shows that an [internal combustion engined vehicle] would need to consume less than 3.9 L/100km to cause lower [environmental impacts] than a [battery car] ... Consumptions in this range are achieved by some small and very efficient diesel [cars], for example, from Ford and Volkswagen.

Actually quite a lot of the new diesels are in the better-than-battery ballpark, according to UK government figures. The notional battery car considered by the EMPA analysts was a Volkswagen Golf with its normal drivetrain replaced by a battery one: but it seems that you would be doing slightly better for the environment to buy an ordinary new Golf with a 1.6 litre "BlueMotion" injected turbodiesel - which would be a lot cheaper. That would consume 3.8 l/100km, not 3.9.

So would a new Mini Cooper D hatchback or a new Ford Focus, actually. And if you could bear to go for something a little smaller - VW Polo rather than Golf - you'd be streets ahead on the environmental front, down as low as 3.4 l/100km with more than 15 per cent of the car's in-service emissions clipped off compared to the 3.9 l/100km battery-car baseline. As the Swiss boffins tell us, it's the in-service energy use and emissions which count most.

You could even treat yourself to a small estate car - the Skoda Fabia - and beat a battery Golf by a large margin in terms of eco-credentials, according to the EMPA analysis.

Of course, battery car lovers will argue that's not the point. Swiss electricity is already largely generated by carbon-free nuclear and hydropower plants (carbon-free provided you don't count all the concrete used to build them, that is). These and other technologies not yet much used (solar, wind, tidal etc) may one day put the battery car far ahead of internal-combustion ones in terms of carbon emissions.

And if nobody buys battery cars now, they'll stay expensive and scarce forever, so it's still possible to view the act of buying one as green even today when they actually do more damage to the environment than the right internal-combustion model.

But if you just want to emit less carbon right away, it seems you should buy a modern eco-diesel rather than an electric vehicle. ®




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NASA - NASA's Successful Ice Cloud and Land Elevation Mission Comes to an End

NASA - NASA's Successful Ice Cloud and Land Elevation Mission Comes to an End
"ICESat has been a tremendous scientific success," said Jay Zwally, ICESat's project scientist at NASA's Goddard Space Flight Center in Greenbelt, Md. "It has provided detailed information on how the Earth's polar ice masses are changing with climate warming, as needed for government policy decisions. In particular, ICESat data showed that the Arctic sea ice has been rapidly thinning, which is critical information for revising predictions of how soon the Arctic Ocean might be mostly ice free in summer. It has also shown how much ice is being lost from Greenland and contributing to sea level rise. Thanks to ICESat we now also know that the Antarctic ice sheet is not losing as much ice as some other studies have shown."




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