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Before then, I suspect. Dr.Hansen needs to talk to a conservation biologist.
Dr. James Hansen: “We Have a Global Emergency” Dangerous Heat to Render Parts of the World Practically Uninhabitable by 2100
4
March, 2016
There’s
a tragic new danger lurking in the world. Something that’s arisen
from a mass burning of fossil fuels on an epic scale that now pumps
out more than 100 times the greenhouse gas emission from all the
volcanoes in all the world combined. Something that’s been building
heat in our atmosphere at unprecedented rates. Something that’s
been increasingly setting off the strange and deadly Hothouse Mass
Casualty Events (HMCE). Events
that appear ready to hit the innocent, the poor, and the vulnerable
among us the hardest.
Over
the past few decades, HMCEs, have occurred with increasing frequency
during periods of extreme heat and drought that exceeded the scope
and intensity of past heatwaves. These events resulted both in mass
human mortality and in medical infrastructure crippling waves of heat
injuries. These new, deadly heatwaves occurred in a world that was
about 0.6 to 0.8 C hotter than 1880s averages. But as of the past two
years, the global heat factor has cranked still higher — hitting
0.9 to 1.1 C above 1880s levels during 2014 and 2015 — and further
increasing the likelihood of these dangerous events.
And
according to a new scientific report from Dr. James Hansen —
these events are about to become an ever-more permanent part of the
global landscape. In essence, if fossil fuel burning continues, the
poorest parts of the world who have contributed the least to the
climate change problem will experience HMCEs with such a high
frequency that many of these regions are going to become practically
uninhabitable by the end of this Century. It’s a level of unfair
and unequal treatment that’s difficult to stomach. For those who
continue to burn fossil fuels, who continue to push fossil fuel
burning through lobbying, market dominance, and short-sighted
government policies, and who plan to burn these harmful fuels on into
the future now appear to be involved in a kind of combined act of
inflicted human habitat destruction and possible genocide.
*****
On
Wednesday, Dr. James Hansen, former head of GISS NASA, and one of the
world’s foremost authorities on human-caused climate
change, dropped
another bombshell on
an in-the-know scientific community that appears to be struggling to
keep up with the velocity of what has now become aGlobal
Warming Emergency. Hansen’s
new report first takes a look at warming in retrospect — using
historical temperature and extreme warming event data to show that
the world has been radically altered by a rampant fossil fuel
emission. Then, Hansen takes a look forward into what appears to be
an increasingly hot and dangerous greenhouse gas warmed future.
(Through
late 2015, Hansen’s data showed that human fossil fuel emissions
continued along a path just above IPCC worst case ranges, and
flirting with the lower edge of absolute worst case ranges. Hansen
here identifies these carbon emissions as a global warming ‘Time
Bomb.’ Image source: Dr.
James Hansen.)
No
More Cool Summers For Some Parts of the World
The
paper found that the frequency of extreme heating events increased
over the globe, even as the likelihood of cool or cold weather fell
off. Though every region showed an increase in warm or hot events and
a drop off in cool or cold events, some regions experienced more
warming than others.
For
example, in the US, summers cooler than the 1951 to 1980 average now
occur only 19 percent of the time. Meanwhile, the frequency of
extreme heating events 3 standard deviations outside the mid 20th
Century average increased by an order of magnitude to 7 percent.
These are strong shifts toward hotter summers for the US. But they
are somewhat minor in comparison to shifts occurring in other parts
of the world.
Hansen
notes that in the Middle East and Mediterranean, rates of summer
warming have increased to the point that
there are now no summers that are cooler than average even
as the period of summer seasonality has grown “considerably
longer.” This statement is worth thinking about for a bit —
essentially what’s happened is cool summers below the mid 20th
Century average have been basically wiped out in the Med and Middle
East. Cool summers there are a thing of a much less dangerous and far
more pleasant past.
And
looking at Hansen’s graph below we find that the impact of warming
in many highly populated regions of the world is already far greater
than within the United States:
(Shift
to hotter Summers and Winters is now producing a greatly increased
frequency of extremely hot summers even as it is steadily eliminating
the likelihood of cool summers. Image source: Regional
Climate Change and National Responsibilities.)
As
the world continues to heat up, there is rising risk to human beings
over broad regions. This is due to the fact that a warming world
increases the latent heat of the atmosphere. When Ocean surfaces warm
to above 35 degrees Celsius, this results in an increase in the
amount of warm moisture in suspension in the atmosphere. For human
beings, it makes it more difficult for heat to transfer way from the
skin through evaporative cooling. At a 35 degree C Wet
Bulb reading,
the human body’s ability to cool itself breaks down — resulting
in high risk of heat stroke and death if exposure continues for 1-2
hours.
The tropics and the Middle East in summer are in danger of becoming practically uninhabitable by the end of the century if business-as-usual fossil fuel emissions continue, because wet bulb temperature could approach the level at which the human body is unable to cool itself under even well-ventilated outdoor conditions. Lesser warming still makes life more difficult and reduces productivity in these regions, because temperatures are approaching the limit of human tolerance and both agricultural and construction work are mainly outdoor activities.
Health-Risks, Violence, Climate Inequality and Responsibility
In
addition to increasing the likelihood of hothouse mass casualty
events, severe heatwaves, and increasing drought prevalence, Hansen
notes added impacts to human beings and human societies. As we’ve
seen with the Zika virus, disease vectors spread into higher
Latitudes as the world warms — increasing the range of harmful and
deadly tropical illnesses. Furthermore, studies indicate that
violence increases dramatically in hotter regions. With each standard
deviation increase in temperature patterns, group
on group conflict has been observed to increase by 14 percent.
This would already have increased conflict in the Med and Middle East
by nearly 30 percent. For many regions of the world, if fossil fuel
burning continues, warming is expected to shift a further 3-7
standard deviations off baseline. If the violence study findings are
correct, this could double instances of group on group conflict for
some parts of the world.
(Unequal
climate change contributions, unequal impacts. Image source: Regional
Climate Change and National Responsibilities.)
One
final assertion of Hansen’s paper is that warming impacts and
contributions are unequal. People living in Asia and Africa are
seeing disproportionate warming even as they have contributed very
little to the problem. And many of the regions now experiencing above
average rates of warming could be rendered practically uninhabitable
by Century’s end. People in the United States, Canada, Australia,
Russia, Japan, and Northern Europe, though also suffering warming
impacts, have been among those contributing the most to the problem
and seeing the lowest rates of change in the form of extreme heat
related events (though those experiencing ever more frequent droughts
in the US Southwest may beg to differ). The Middle East’s own
moderate national emissions contribution to global warming (though a
rather high export contribution in the form of oil and gas sales) is
matched by an extreme commitment to dangerous heatwaves for the
region. This distribution represents a highly unequal and unfair
spread of climate impacts and climate change responsibility. Yet one
more reason why the industrial nations of the world should be getting
their act together for a concerted and rapid transition away from
fossil fuel use.
It’s
worth noting that the Hansen paper does not assess the impact of
other climate change related events such as extreme rainfall or sea
level rise on regions that have contributed the most to the problem.
It’s likely that vulnerable cities would see a widely distributed
impact from the kind of multi-meter sea level rise Hansen warns is
possible rippling across the globe. Portions of the US East and Gulf
Coasts, in particular, have an extraordinary vulnerability to this
climate change related threat.
Links:
Hat
tip to TodaysGuestIs
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