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posted by martyb on Wednesday October 19 2016, @01:09PM   Printer-friendly
from the freedom-of-the-press dept.

Amy Goodman, host of the New York City-based leftist news programme Democracy Now! was charged with criminal trespass by the North Dakota state's attorney (prosecutor). The charge was changed to riot, then was dismissed due to lack of evidence when Goodman appeared in court on Monday. The charges stemmed from her presence at a protest in September against construction of the Dakota Access (Bakken) oil pipeline, after the protest was reported on her show.


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  • (Score: 2) by butthurt on Saturday October 22 2016, @07:22AM

    by butthurt (6141) on Saturday October 22 2016, @07:22AM (#417541) Journal

    > So can the hypothesis that ozone holes happen on a regular basis for the past two million years.

    I'll accept that that statement amounts to a hypothesis. We have observations of an 11-year solar cycle and a 1-year seasonal cycle. Those changes in solar flux would be expected to result in changes to the ozone. Your hypothesis "explains" the Dobson unit measurements by supposing there are longer-term oscillations; it doesn't explain what would cause oscillations on a longer time scale.

    > But you're falling for one of the classic scientific blunders: assuming that a phenomenon that you've seen for the first time has happened for the first time.

    The sources I quoted say there's not only an ozone hole but a global decrease in ozone. If that's been happening repeatedly on a time scale that's much longer than the Dobson unit observations (which at one station in Switzerland go back to 1932), we should expect that the current ozone levels are neither the highest nor the lowest that have occurred. Extreme ozone depletion in the past could be observed indirectly through its effects on organisms. People have looked into that (emphasis added):

    We analyzed bulk UV absorbance of methanolic extracts and levels of five UV-absorbing compounds (hydroxycinnamic acid derivatives) in 135 herbarium samples of the liverwort Jungermannia exsertifolia subsp. cordifolia from northern Europe. Samples had been collected in 1850–2006 (96% in June–August). Both UV absorbance and compound levels were correlated positively with collection year. p-Coumaroylmalic acid (C1) was the only compound showing a significant (and negative) correlation with stratospheric ozone and UV irradiance in the period that real data of these variables existed. Stratospheric ozone reconstruction (1850–2006) based on C1 showed higher values in June than in July and August, which coincides with the normal monthly variation of ozone. Combining all the data, there was no long-term temporal trend from 1850 to 2006. Reconstructed UV showed higher values in June–July than in August, but again no temporal trend was detected in 1918–2006 using the joint data. This agrees with previous UV reconstructions.

    -- []

    Just going by the abstract, those researchers saw what they call "monthly" variation, which I would call a yearly cycle. They didn't see long-term variations. Of course, their idea of what's "long-term" is nothing like two million years. It is, however, multi-decadal.

    Another author wrote (emphasis added):

    The stratospheric ozone layer, which protects the biosphere from biologically active (mostly harmful) ultraviolet-B (UV-B) solar radiation, thinned during the latter half of the 20th century. In this paper some of the effects of UV-B radiation on cryptogams (cyanobacteria, algae, lichens, mosses, liverworts, pteridophytes and fungi) are reviewed. Effects vary among species, and therefore changes in UV-B radiation may affect species frequencies. Effects also depend on other factors, such as water conditions.

    -- []

    > You need data that distinguishes between hypotheses rather than merely assume that your favorite hypothesis is true.

    It's all right to have just one hypothesis; the alternative of acknowledging our ignorance is always available.

    > The hypothesis that CFCs destroy stratospheric ozone is not a bad hypothesis and it is far from ruled out by what we know.

    Destruction of ozone by chlorine species was observed in the laboratory, and there was the global "experiment" with CFCs. Data from those--apart, perhaps, from the liverwort paper I quoted above--seem adequately consistent with the hypothesis, although ozone depletion happened more quickly than was predicted. It doesn't look to me as though acknowledging our ignorance is preferable. Supposing that the ozone oscillates naturally for unknown reasons isn't much different than that.

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  • (Score: 1) by khallow on Saturday October 22 2016, @02:40PM

    by khallow (3766) Subscriber Badge on Saturday October 22 2016, @02:40PM (#417578) Journal

    Your hypothesis "explains" the Dobson unit measurements by supposing there are longer-term oscillations; it doesn't explain what would cause oscillations on a longer time scale.

    We do know there are such variations in both climate and solar output and both are relevant (though climate related effects matter significantly more) to ozone production over the Antarctic. In particular, we know that the ozone hole is due in large part [] to isolation of the upper atmosphere due to polar vortex and high altitude cloud formation prior to the beginning of the Southern hemisphere spring (and return of sunlight to the Antarctic).

    It's all right to have just one hypothesis; the alternative of acknowledging our ignorance is always available.

    Sure, it is when the consequences of the hypothesis being more or less correct can be ignored. A key problem here is that global policy on refrigerants has been decided on the basis of a certain chemistry model of the stratosphere. But if natural variation is being ignored, then it indicates that the model's estimates of, for example ozone generation and depletion as well as the life span and effects of chlorine in the stratosphere can be very wrong, resulting in policy affected billions of people being based on bad models and data.