Best Primer to Climate Change ever

The Beeb does it again. Best use of simple graphics to clearly explain science.

Gulf Stream

  1. Surface currents carry warm, salty water from the tropics.
  2. The water cools, its density increases and it sinks to the deep ocean.
  3. The cold water flows back to the equator, driving the “ocean conveyor” which in turn contributes to the Gulf Stream that warms northern Europe.
  4. As ice melts, freshwater dilutes the warm salty water from the tropics.
  5. The water becomes less dense so does not sink as fast, weakening the “conveyor” and therefore possibly disrupting the Gulf Stream.

Gulf Stream

Dramatic temperature shifts have happened in the past, driven partly by changes in a major ocean currents.

A “great ocean conveyor” helps transport heat around the globe via surface and deep-sea movements of water.

Scientists are exploring whether global warming might slow or shut it down – a scenario considered “low probability, high impact”.

This could disrupt mostly wind-driven surface currents such as the Gulf Stream, which brings milder weather to Northern Europe.

Low Probability, High impact indeed, aka the “Hell Freezes Over” Scenario. The Gulf Stream example is one of my favorites, check all the other animation out, it is great.

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    US court hands EPA a win in utility emission case | Reuters.com

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    via Obama: Warming must be tackled now – Climate Change- msnbc.com

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    Eastern United States vulnerable to climate change

    http://www.eurekalert.org/pub_releases/2007-12/pu-sdn121007.php
    6157_rel.jpg
    Time to get out of the Eastern United States? A study to be published in the Proceedings of the National Academies of Science tries to quantify the relative risk of climate change using something called a “socioclimatic” risk factor. As always, the redder the worse. A look at the paper would no doubt be more illuminating, but for some reason, press releases about PNAS papers come out way before the papers actually become public. China is in bright red all the way, India in a rather bright orange. Where I live, the Eastern United States, is a nice beet red. No doubt, the unprecedented drought the South is experiencing right now is a nice big red signal.

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    Soto and her colleagues exposed pregnant rats to bisphenol A at doses ranging from 2.5 to 1,000 µg per kg of body weight per day. By the time the pups exposed at the lowest dose reached the equivalent of puberty (50 days old), about 25% of their mammary ducts had precancerous lesions, a proportion three to four times higher than among the nonexposed controls. Mammary ducts from all other exposure groups showed elevated levels of lesions. Cancerous lesions were found in the mammary glands of one-third of the rats exposed to 250 µg/kg/day.

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