CHRIS WOOD: NATURAL SECURITY
Published March 21, 2014
Rube Goldberg is long dead, but the figurative machine to which he gave his name lives on. It’s that whimsical confection where a rolling marble tips a lever that sends a toy plane whizzing down a wire to bump into a scissors that cuts a string that drops a water balloon on a sleeping victim — or some variation with even more steps. Assemblies of apparently unrelated parts accomplishing as little as possible.
Earth’s climate is a lot like a Rube Goldberg machine: a vast assembly of invisibly connected parts, pushing and pulling each other around the spherical planet to achieve, for the last 12,000 years at least, a lot of movement of heat and wind and water, but very little change in the overall state of affairs. Some of its parts are like ‘levers’ that nod back and forth between different conditions (the famous el niño is of this type). Others are more like toy planes on wires, zipping energy from place to place (monsoons and jet-streams are like that).
Which brings me to teleconnections.
These are not what you may think. They are neither what Scottie did to beam Spock and Captain Kirk back up to the Enterprise, nor a new form of television-based hookup plan. They are what happens when something on one side of the planet produces an effect — mediated by a lot of those intermediate climatic cogs and levers — on the other.
The famous niño/niña twins, more formally known as the ENSO (“El Nino Southern Oscillation”), are alternating pools of relatively warmer and cooler than average water extending west out into the eastern Pacific from the ‘bulge’ of South America. When the pool is warm (el niño), torrential rains extend from Peru all the way up to southern California. The northwest of the United States and Canada get relatively warm and dry winters. The effects are felt as far away as east Africa, which gets more winter rain, and Australia, which gets scorching summers. When the oscillation is in its other, chilly, la niña mode, many of those effects are reversed: drought in Southern California, a wet winter for the northern Rockies.
The less evocatively named North Atlantic Oscillation — a rocker-arm of alternating high and low air pressure centred on Iceland — may have played a role in the ferocity of North America’s latest winter. When NOA is in its negative mode (weak low pressure over Iceland), the jet-stream — normally another of those energy-zipping wires in the machine — is blocked from crossing the Atlantic. It slows and meanders, delivering blizzards to New York and comparatively mild days to Baffin Island. The effects continue on into Europe, where warm and wet, vs. cold and dry, effects alternate over northern and southern parts of the continent.
Those and other teleconnections have been teased out of the global data. More are just being discerned: a possible causal connection between less summer ice in the Arctic, and more winter snow in Alabama and Georgia (suggesting a different explanation for the slowdown of the jet stream), for example, remains a hypothesis awaiting confirmation. Another recent paper suggests that Olga, a north Atlantic hurricane in 2001, was to blame for unusually heavy rain later that year in the eastern Mediterranean.
And sometimes teleconnections are neither obvious nor intuitive. An eruption of Iceland’s Laki volcano in 1783 went unnoticed in Europe. But the eruption sent so much ash and gas into the high atmosphere that it darkened the skies downwind, sufficiently to alter the balance of forces that, Goldberg-like, coax moisture out of the southern Indian Ocean and deliver it to India and Africa in seasonal monsoons. When the monsoons failed in 1784, famine broke out in both regions. The Nile fell to a historic trickle.
The movement of heat from the tropics toward the poles is generating stronger winds in the high southern latitudes. These may now be having the paradoxical effect of stretching out the sheets of seasonal sea ice that form around Antarctica — giving the impression of more extensive (if not more massive) ice formation.
And here’s the thing about our Rube Goldberg climate system: we know we’re making the whole shebang run faster — that’s the fuel effect of all the extra planetary heat being captured by greenhouse gases. But we only know some of its working parts. We’re comparatively ignorant of all the intermediate stages in the machine: how many swinging boots have to wake up how many chickens to lay eggs to roll down a ramp to … produce that perfect spring day for gardening.
Something we also know is that from time to time in the past, the machine has spontaneously reorganized its flows of energy, expressed in the movement of air, water and heat around the globe. The machine is still working, but all of its circuits have changed. Now the chickens are sending the toy planes down the wires to light a rocket. Or to step back from the metaphor: different conditions upstream in the climate circulation may sharply rearrange its geography and calendar downstream. Dim skies over Scandinavia, cloudless ones over Gujarat and Cairo.
That may be what we have witnessed in the ‘polar vortex’ that settled its frigid skirts over east-central North America this year: the first intimation of how Goldbergian planetary teleconnections are slipping their familiar cogs and reengaging with other parts of the climate machine.
How different might the machine’s performance become? Very. “We are at risk of pushing our climate system toward abrupt, unpredictable, and potentially irreversible changes with highly damaging impacts,” the American Association for the Advancement of Science concluded in a report released this month.
Rube’s swinging hammer may come down on all our heads.
Copyright © 2014 Chris Wood
Meet some more teleconnections at NOAA’s site: http://www.cpc.ncep.noaa.gov/data/teledoc/teleintro.shtml
Or visit Rube Goldberg’s legacy (and some original designs) at http://www.rubegoldberg.com/
Read the American Association for the Advancement of Science warning on climate disruption here: http://whatweknow.aaas.org/get-the-facts/