Earth
experiences cyclical warming and coolin due to long
term orbital and tilt change:
Milankevitch cycles. Paleometiorologists
currenty think we are still coming out of the most
recent glacial period, but that human activity is causing the cycles to speed up. The "tipping point" that they take most seriously seems to be the melting of north polar ice, which, they say, could, they think, open a wide ice free passage, which could allow the warm Gulf Stream to flow over the top of the the North American continent, essentially over the geographic pole. It could then, they fear, flow southward down the Pacific and cause further problems on both American continents. The loss of Gulf Stream warmth could also greatly cool Europe. |
At the same time, warm Gulf Stream water flowing through the frigid north would evaporate and could cause heavy snowfall in the northerh hemisphere, perhaps enough snowfall that there would be more winter snow than could melt over shortening summer seasons. And that is recipe for a quckly descending Ice Age. But as you could see reading through the worrisome argument, they have included many conditionals: "might, could, perhaps, they fear", etc., that mask the fact that like modern, non-paleo-meteorologists, they are just "weather guessers". |
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Ice Age Mediterranean |