Thursday, June 18, 2009

Aerosol cooling overestimated, says new study - physicsworld.com
By bringing the two approaches into line, Myhre calculates a new best estimate of -0.3 Wm-2 for the cooling of the direct aerosol effect. He says that this will tend to reduce future projections of global warming.
GCCI #6: A Ridiculously Narrow Time Window - Glaciers | Climate Skeptic
I hope you can see why it is unbelievably disingenuous to truncate the whole period from 1800-1960 and call this trend a) recent and b) due to man-made global warming. If it is indeed due to man-made global warming since 1960, then there must have been some other natural effect shrinking glaciers since 1825 that fortuitously shut off at the precise moment anthropogenic warming took over. Paging William of Occam, call your office please.

Similarly, sea levels have been rising steadily for hundreds, even thousands of years, and current sea level increases are not far off their average pace for the last 200 years.
[Ridiculous theory: small amounts of CO2 are terrible for plants] - Sudden Collapse in Ancient Biodiversity: Was Global Warming the Culprit? - US National Science Foundation (NSF)
Scientists have unearthed striking evidence for a sudden ancient collapse in plant biodiversity. A trove of 200 million-year-old fossil leaves collected in East Greenland tells the story, carrying its message across time to us today.

Results of the research appear in this week's issue of the journal Science.

The researchers were surprised to find that a likely candidate responsible for the loss of plant life was a small rise in the greenhouse gas carbon dioxide, which caused Earth's temperature to rise.
[Real life observations: small amounts of CO2 are great for plants]: Carbon Dioxide In [Actual] Greenhouses
For the majority of greenhouse crops, net photosynthesis increases as CO2 levels increase from 340–1,000 ppm (parts per million). Most crops show that for any given level of photosynthetically active radiation (PAR), increasing the CO2 level to 1,000 ppm will increase the photosynthesis by about 50% over ambient CO2 levels.
...
The level to which the CO2 concentration should be raised depends on the crop, light intensity, temperature, ventilation, stage of the crop growth and the economics of the crop. For most crops the saturation point will be reached at about 1,000–1,300 ppm under ideal circumstances. A lower level (800–1,000 ppm) is recommended for raising seedlings (tomatoes, cucumbers and peppers) as well as for lettuce production. Even lower levels (500–800 ppm) are recommended for African violets and some Gerbera varieties. Increased CO2 levels will shorten the growing period (5%–10%), improve crop quality and yield, as well as, increase leaf size and leaf thickness. The increase in yield of tomato, cucumber and pepper crops is a result of increased numbers and faster flowering per plant.
...
Carbon dioxide can be obtained by burning carbon-based fuels such as natural gas, propane, and kerosene, or directly from tanks of pure CO2. Each source has potential advantages and disadvantages.

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