One of the facts that might be overlooked in this report is that we are in fact currently on pace to achieve a rise in temperatures a full 2 degrees higher then the report itself warns we must not achieve. Which may be behind the decision by these scientists to be alarmist in their tone, since these reports have otherwise been characterized by their conservative approach up to this point.
http://nymag.com/intelligencer/amp/...-genocide-coming-but-its-worse-than-that.html
.....the new report’s worst-case scenario is, actually, a best case. In fact, it is a beyond-best-case scenario. What has been called a genocidal level of warming is already our inevitable future. The question is how much worse than that it will get.
Barring the arrival of dramatic new carbon-sucking technologies, which are so far from scalability at present that they are best described as fantasies of industrial absolution, it will not be possible to keep warming below two degrees Celsius — the level the new report describes as a climate catastrophe. As a planet, we are coursing along a trajectory that brings us north of four degrees by the end of the century. The IPCC is right that two degrees marks a world of climate catastrophe. Four degrees is twice as bad as that. And that is where we are headed, at present — a climate hell twice as hellish as the one the IPCC says, rightly, we must avoid at all costs. But the real meaning of the report is not “climate change is much worse than you think,” because anyone who knows the state of the research will find nothing surprising in it. The real meaning is, “you now have permission to freak out.”
At two degrees, the melting of the Arctic ice sheets will pass a tipping point of collapse, flooding dozens of the world’s major cities this century — and threatening, over many centuries, to elevate sea level as much as 200 feet.
At three degrees, southern Europe will be in permanent drought. The average drought in Central America would last 19 months and in the Caribbean 21 months. In northern Africa, the figure is 60 months — five years. The areas burned each year by wildfires would double in the Mediterranean and sextuple in the United States.
At four degrees, there would be eight million cases of dengue fever each year in Latin America alone. Global grain yields could fall by as much as 50 percent, producing annual or close-to-annual food crises.
None of the above is news — most of that data is drawn from
this single, conventional-wisdom fact sheet. In fact, nothing in the IPCC report is news, either; not to the scientific community or to climate activists or even to anyone who’s been a close reader of new research about warming over the last few years. That is what the IPCC does: It does not introduce new findings or even new perspectives, but rather corrals the messy mass of existing, pedigreed scientific research into consensus assessments designed to deliver to the policymakers of the world an absolutely unquestionable account of the state of knowledge.
Almost since the panel was convened, in 1988, it has been criticized for being too cautious in its assessment of the problem — a large body of temperamentally cautious scientists zeroing on those predictions they can all agree on (and which, they may have hoped, policymakers might find workable). The panel’s
Wikipedia page has separate subsections for “Outdatedness of reports” and “Conservative nature of IPCC reports.”
Which is why it is so remarkable that the tone of this report is so alarmist — it’s not that the news about climate has changed, but that the scientific community is finally discarding caution in describing the implications of its own finding.