what we see now is the visible formation of a large cool pool in the
North Atlantic. One that appears to be developing due to an
increasingly rapid rate of Greenland melt. One that may be setting up
atmospheric conditions for
the age of storms that Hansen has feared could arise.
An event resulting from a rampant human fossil fuel emission and a
related very rapid injection of heat into the Earth System.
global temperature anomaly data from NOAA for 2013 through 2015
provides evidence of the early start to the formation of a possible
superstorm-producing North Atlantic cool pool. Image source: Climate
might this cool pool become such a powerful storm generator? It could
well be thought of as an ironic matter of atmospheric and ocean
physics. Ironic in the sense that overall global heating produces a
severe weather hazard in the form of a large area of cool ocean
warming of the Earth results in more rapid warming at the poles,
especially in the Northern Hemisphere. In turn, this polar
amplification sets off a number of feedback loops in which ice in
Greenland and West Antarctica begin to melt faster and faster. The
ironic atmospheric relationship to large slabs of ice sliding off the
great ice sheets and into the ocean begins to come into play. For a
thin veil of fresh water from these increasingly massive volumes of
melting ice begin to lock more and more heat into the local ocean
hundreds of thousands of square kilometers, the fresh water begins to
cut off the ocean’s ability to ventilate heat into the airs above.
As a result, the surface of the ocean and the local atmosphere cools.
More heat is shoved into the deeper waters — where it can melt the
sea facing glaciers ever more rapidly even as it gets to doing the
dangerous work destabilizing carbon stores on the sea bed. Dangerous
— not only for its potential to add more greenhouse gasses to the
world atmosphere, but also for its ability to develop anoxic dead
zones in the ocean depths and to expand those life-killing layers
toward the sea surface.
Change’s War Between Hot and Cold — Understanding the Warning
scientific terms, we call this a stratified ocean state. But in
plainer words, we could think of it as a big mechanism for heat
exchange and ocean and atmospheric chemistry change.
who knows anything about ocean and atmospheric physics should be
concerned about this picture. Here we see the April 8, 2016 ocean
surface temperature anomaly reanalysis provided by Earth
developed from data collected by NCEP and
Here we see a large swath of Gulf Stream waters ranging from 5-8 C
above average temperatures coming into collision with waters in a
North Atlantic cool pool ranging from 1-10 C below average. It is the
increasing difference in temperature, or thermal gradient, between
these two ocean zones that Hansen and others identify as having a
high potential for very severe storm generation.)
the ocean’s heat relationship with the atmosphere is bound to alter
the weather. And Hansen’s
toward a serious risk that this fundamentally altered relationship
will result in much more powerful storms. A cooler North Atlantic
will collide with all kinds of expanding heat from various regions. A
backed up Gulf Stream will warm up — it already has. The tropics
will begin to heat up, increasing the temperature gradient between
the lower Latitudes and the cool pool in the North Atlantic. Such
conditions amp up the atmospheric storm potential by producing an
abundance of what storms feed on — very extreme differences in
temperatures, related strong winds and atmospheric vortexes, strong
south to north and north to south air flows that link the tropics to
the pole, and an ever-growing abundance of moisture bleeding off the
record warm waters that come into increasing collision with the
expanding pool of cold to the north.
Such conditions risk the
development of extraordinarily powerful storms in this region. Storms
the likes of which our civilizations have never seen before. Storms
that may leap the boundaries of their formation zones to have far
his paper found
evidence that such conditions may well have existed during the last
warm period between ice ages around 115,000 years ago. Back then, a
huge flush of ice bergs running out from a melting Greenland during
the peak period of warmth appears to have produced terrible storms in
the North Atlantic. Storms powerful enough to pluck 2,000 ton
boulders up out of the sea bed and hurl them 100 feet above sea level
before depositing them onto the hills of places like Bermuda and the
that period, the rate of warming was slower. So the pace of melt was
likely also slower than what we would see due to human warming. The
atmospheric changes were thus milder than those we are likely to
experience if human warming continues along its current path and sets
the dramatic melt and related atmospheric wrenching into motion.
Already, we see storms the likes of which history has never seen
running into the UK and Ireland, aiming their increasingly powerful
winds and rains at Western Europe. Already
we see climate change enhanced superstorms.
New forms of severe weather. Hellacious mergings of devastating
hurricanes with extraordinary nor’easters.
what we see now is nothing compared to what we will see if Hansen’s
research is anywhere near the mark and if human fossil fuel burning
continues unabated. What we risk, and what Hansen has warned us about
in what he considers to be his most important work of science, is
setting off a severe chain of events that includes rapid sea level
rise and powerful, powerful storms. In addition, the ocean
stratification that is the cause of all this atmospheric and oceanic
trouble would set off further consequences not touched on in Hansen’s
work — hitting ocean health hard and, likely, liberating more
carbon stores from the Earth System to add to the troubles that
humans (and particularly the fossil fuel special interests) are
already rapidly bringing to the fore.
final point — the Hansen paper has and will continue to generate a
huge controversy in the science. But from the point of view of this
threat analyst, there is a high potential for dangerous outcomes
similar to those the Hansen paper warns of together with a number of
additional troubles so long as the human-forced warming continues.
And we already see visible evidence of those kinds of dangerous
atmospheric and ocean changes starting to happen now.