A revista Nature revisita os principais mitos climáticos ventilados pelos denegacionistas da responsabilidade humana no aquecimento global, ou mesmo da existência desse fenómeno:
"Climate scientists grapple with real uncertainties, but those who doubt
the reality of human-driven global warming usually ignore those issues
and, instead, perpetuate a series of claims that do not hold up to
scrutiny. What follows is a selection of myths about climate:
Climate models can't provide useful information about the real world.
Models can reproduce much of the climate variation over the past
millennium, but projections for the future are subject to
well-described uncertainties, both in the understanding of climate and
in estimates of future economic development. They cannot therefore
provide decision-makers with exact information of the rate of future
changes, but they can offer useful general information and they
unconditionally predict a warmer world.
Global warming stopped ten years ago.
Climate is not weather. The climate is the multi-decade average of the
constantly changing state of the atmosphere. Natural variations can
cause temperatures to rise and fall from year to year or decade to
decade. Although global temperatures did not rise as quickly in the
past decade as in previous ones, the most recent decade was the warmest
on record.
Temperatures were higher in pre-industrial times.
The consensus of proxy-based reconstructions of pre-industrial climate
is that the second half of the twentieth century was probably warmer
than any other half-century in more than a millennium. Warmer periods
did occur in the more distant past, albeit under different orbital and
geological conditions. In any case, warm spells in the past do not
disprove human influence on climate today. The cause of any particular
climate change needs to be investigated separately.
Temperature records taken in the lower atmosphere indicate that the
globe is not warming.
A decade ago, there seemed to be a discrepancy between surface and
tropospheric temperatures. But this issue was resolved when
long-standing calibration problems with satellite sensors were
discovered. Satellite measurements show that the lower atmosphere is
warming at a rate consistent with the predictions of climate models.
A few degrees of warming are not a big deal.
In the most recent ice age, the world was only a few degrees cooler on
average than it is today. The current rate of warming is in all
likelihood unique in the history of humankind. There may be no such
thing as an 'optimum' temperature for the planet, but modern human
societies are adapted to the weather patterns and sea levels of the
past millennia. The rapidity of global warming substantially adds to
the problem.
Measured increases in temperature reflect the growth of cities around
weather stations rather than global warming.
Climate researchers have taken great care to correct for the impact of
urbanization in temperature records by matching data from more-urban
stations with data from rural ones. Moreover, some of the largest
temperature anomalies on Earth occur in the least populated areas,
including around the Arctic and the Antarctic Peninsula. Measurements
also show warming of the surface ocean and deeper marine layers."
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