One of the obvious problems with predicting the future effects of climate change is that they haven’t happened. This makes clima

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问题     One of the obvious problems with predicting the future effects of climate change is that they haven’t happened. This makes climate studies highly dependent on models, which invariably and unavoidably make simplifying assumptions. This means that using their results to say anything of practical import needs care and caveats, both of which can often be in short supply, or stripped out to make a point.
    However, it is now ever more possible for studies of climate change to look at the past, not the future. The 20th century saw a fair amount of warming, and it is sometimes possible to compare what this warming did and didn’t do with what future warming might or might not do. This is what a paper published in Nature this week does in an attempt to re-examine, and perhaps close down, long-running debates about malaria and climate change.
    Both the malaria parasite and the mosquitoes which spread it respond to temperature and moisture. Understanding those responses makes it possible to model what changes in climate might mean to the incidence of the disease. Such models have suggested that in a warmer world the area subject to endemic malaria would increase, perhaps quite a lot, though some places would see a reduction due to increased aridity. The caveats here include noting that the climate models can make no great claims to accuracy at the regional level and that such an approach does almost nothing to deal with changes in land use, wealth and public health programs.
    One of the main thrusts of the new Nature paper is to see how much of what happened to the spread of malaria in the 20th century can be explained by what happened to the climate. The answer, according to Peter Gething of Oxford University and his colleagues, is not much. They conclude that claims that a warming climate has led to more widespread disease and death due to malaria are largely at odds with the evidence, which shows the areas effected shrinking, and the size of the effect shrinking too. Increases in the spread and severity of the disease burden foreseen over the next 40 years by the biological models are far smaller than the decreases in comparable measures seen over the past century.
    The second tack of their argument is to compare the sort of effect seen in biology-based models of where malaria might spread with both models of and data on the effects direct intervention against the disease can have. Again the effects due to climate are small, even negligible, compared with the effects that interventions have achieved already and might achieve in decades to come. The marginal areas where climate might enlarge the area at risk are also, the article argues, the areas where the greatest declines in transmission have recently been seen thanks to increased intervention.
    The conclusion is clear. People who are thinking about what to do about malaria should bear in mind that the biological basis of its distribution may change in a warmer world. Those thinking about the overall danger that climate change represents should not spend their time worrying about its impact on malaria.
    Is there a wider conclusion to draw about computer models such as those that underlay frightening statements about malaria in a climate-changed world? Perhaps; but like the models themselves, it comes with caveats.
    Scientists tend to model what can be modeled, and natural scientists, in particular, tend to prefer models that incorporate at least some aspects of the underlying processes which they are interested in, rather than working purely on empirical correlations. This means that if you search the scientific literature for approaches to the future, you will tend to find answers based on natural processes. If other knowledge suggests that natural processes aren’t the most important aspect of the problem at hand, then it’s a good idea to look at the models with that provision in the forefront of your mind.
    The other vital lesson is that the caveats matter. Pretty much every paper presenting a biology-based model of malaria’s dependence on climate contains a warning that changes in economy, technology and society matter too, and aren’t in the model. To transmit the model’s results without important caveats is reckless.
    If one is going to be optimistic about the future of malaria, one might also, with caution, be optimistic about the future of assessments of climate change. Things can, over time, get better, especially when the record of what has happened to date gets taken seriously. They will do so quicker if people accept both the usefulness and limits of models of the future, as well as the appeal of models of the past.  
Which of the following statements is CORRECT as for the new Nature paper?

选项 A、The paper found that the warming climate had led to more malaria.
B、The paper aroused disputes about malaria and climate change after publication.
C、The paper concluded that the spread of malaria could be explained by climate changes.
D、The paper tried to study the effect of climate changes on malaria during the past 20th century.

答案D

解析 细节题。第二段指出,现在研究气候变化不一定非要立足于未来,从历史角度出发也成为一种可能。20世纪人类经历了大规模的全球变暖,我们可以通过研究过去全球变暖带来的后果,来预计其对未来世界的影响,故[D]符合文意,为正确答案。第四段第三句提到,气候变暖引起疟疾扩散的说法与事实不符,故排除[A];第二段最后一句指出,该篇论文可能会结束长期以来关于疟疾流行和气候变化之间关系的争议,故排除[B];第四段第二句指出,气候变暖无法解释疟疾的扩散,故排除[C]。
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