Sabtu, 01 Februari 2014

Abrupt Climate Change - by Paul Beckwith

by Paul Beckwith

Humans have benefited greatly from a stable climate for the last 11,000 years - roughly 400 generations. Not anymore. We now face an angry climate. One that we have poked in the eye with our fossil fuel stick and awakened. Now we must deal with the consequences. We must set aside our differences and prepare for what we can no longer avoid. And that is massive disruption to our civilizations.

In a nutshell, the logical chain of events occurring is as follows:
  1. Greenhouse gases that humans are putting into the atmosphere from burning fossil fuels are trapping extra heat in the earth system (distributed between the oceans (93%), the cryosphere (glaciers, ice sheets, sea ice for 3%), the earth surface (rocks, vegetation, etc. for 3%) and the atmosphere (only an amazingly low 1%). The oceans clearly get the lions share of the energy, and if that 1% heating the atmosphere varies there can be decades of higher or lower warming, as we have seen recently. This water vapor rises and cools condensing into clouds and releasing its stored latent heat which is increasing storm intensity.
  2. (i)Rapidly declining Arctic sea ice (losing about 12% of volume per decade) and (ii)snow cover (losing about 22% of coverage in June per decade) and (iii)darkening of Greenland all cause more solar absorption on the surface and thus amplified Arctic warming (global temperatures have increased (on average) about 0.17oC per decade, the Arctic has increased > 1oC per decade, or about 6x faster)
  3. Equator-to-Arctic temperature difference is thus decreasing rapidly
  4. Less heat transfer occurs from equator to pole (via atmosphere, and thus jet streams become streakier and wavier and slower in west-to-east direction, and via ocean currents (like Gulf Stream, which slows and overruns continental shelf on Eastern seaboard of U.S.)
  5. Storms (guided by jet streams) are slower and sticking and with more water content are dumping huge torrential rain quantities on cities and widespread regions at higher latitudes than is “normal”.
  6. A relatively rare meteorological event called an “atmospheric river” is now much more common, and injects huge quantities of water over several days to specific regions, such as Banff (with water running downhill to Calgary) and Toronto and Colorado events.
The above is extracted from one of Paul's earlier posts.

Paul discusses more details in the videos below. Our abruptly changing climate system: where we are and where we are going.

Abrupt Climate Change - part 1


And the next part, Abrupt Climate Change - part 2


Extreme weather is like a sledgehammer repeatedly pounding away at the inaction, lethargy, and climate change denial that is prevalent in rich Western countries around the world.

Inevitably, the hammer pounding will increase in frequency, severity, duration, and spatial extent over the next few years until the denial crumbles, in spite of the annual one billion dollars in fossil fuel money that is paid to support fraud by hiding the truth on the threat that we all face. 

A tipping point in collective societal behaviour will occur, and humanity will finally initiate action, albeit frantically, to begin to deal with the largest problem ever faced in our history.




Paul Beckwith is a part-time professor with the laboratory for paleoclimatology and climatology, department of geography, University of Ottawa. He teaches second year climatology/meteorology. His PhD research topic is “Abrupt climate change in the past and present.” He holds an M.Sc. in laser physics and a B.Eng. in engineering physics and reached the rank of chess master in a previous life.

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