Sunday, June 24, 2012

RealClimate: Far out in North Carolina

We’re here because of the several metres thick peat layer which has accumulated during the past millennia behind the Outer Banks. The land here is still sinking since the end of the last Ice Age, because it is located on the glacial forebulge: a zone around the edges of the glacial ice sheets that was pushed up when the ice load was pushing down adjacent lands. So instead of getting post-glacial uplift it suffers from post-glacial subsidence. The subsidence has led to a continuous sea-level rise relative to the land of around one millimetre per year. The salt marsh is able to keep up with this rise by accumulating sediments and building up peat, about a metre per millennium.

HH Lamb–“Climate: Present, Past & Future–Vol 2”–In Review–Part I « NOT A LOT OF PEOPLE KNOW THAT

Medieval Warming Period

Lamb had no doubt that the MWP was real and global.

Evidence already cited at various places in this volume suggests that, for a few centuries in the Middle Ages, the climate in most parts of the world regained something approaching the warmth of the warmest postglacial times.

He cites many examples in Europe and North America which indicate warmer temperatures than now.

  • The northern limit of vineyards with a long history of cultivation lay some 300-500 km north of the limit of commercial vineyards in the 20thC.
  • In many parts of England there are traces of medieval tillage far above anything attempted in the present century, even in wartime: up to 350 m above sea level on Dartmoor and 320 m in Northumberland.
  • The tree line and upper limits of various crops on the hills of Central Europe were higher than today.
  • Mining operations at high levels in the Alps which had long been abandoned were reopened, and water supply ducts were built to take water from points which were subsequently overrun by glaciers and are in some cases still under ice.
  • In Central Norway the area of farming spread 100-200m up valleys and hillsides from 800 – 1000 AD, only to retreat just as decisively after 1300 AD.
  • The Viking colonies in W and SW Greenland were able to bury their dead sheep in soil that has since been permanently frozen.
  • It was also a warm period generally from N Mexico to N Canada, where forest remnants between 25 and 100 km north of the present limit have been found, radio carbon dated between 880 and 1140 AD.

The New Nostradamus of the North: "Cars For Climate Justice"?

Scientific American reports that "Poor communities, such as East Boston, are on the front lines of the environmental disruptions expected as a result of global warming":

New Study: Bigger Is Better When It Comes To Wind Turbines | ThinkProgress

According to a  Swiss study, “the larger the (wind) turbine is, the greener the electricity becomes.” The study claims that for every doubling of the size of the turbine, “global warming potential per kWh (is) reduced by 14%.”

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