9.According to Edwards, there is no lack of such mechanisms.If you add their effects together, there is more than enough feedback to make Milankovitch work, he says.The problem now is identifying which mechanisms are at work. This is why scientists like Edwards are not yet ready to give up on the current theory.Milankovitch cycles give us ice ages roughly when we observe them to happen.We can calculate where we are in the cycle and compare it with observation, he says.I cant see any way of testing [Ehrlichs] idea to see where we are in the temperature oscillation.
10.Ehrlich concedes this.If there is a way to test this theory on the sun, I cant think of one that is practical, he says.Thats because variation over 41,000 to 100,000 years is too gradual to be observed.However, there may be a way to test it in other stars: red dwarfs.Their cores are much smaller than that of the sun, and so Ehrlich believes that the oscillation periods could be short enough to be observed.He has yet to calculate the precise period or the extent of variation in brightness to be expected.
11.Nigel Weiss, a solar physicist at the University of Cambridge, is far from convinced.He describes Ehrlichs claims as utterly implausible.Ehrlich counters that Weisss opinion is based on the standard solar model, which fails to take into account the magnetic instabilities that cause the temperature fluctuations.
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