Monday, May 21, 2018

While We Are Distracted

                                                                                                written 5 May, 2018
                                                                                                published 12 May 18

            We are a third through the Trump presidency, a reality show of "All Trump All The Time".  The ongoing fascination and horror of the next tweet, the next fired official, the next scandal, or the next gross incompetence, is an exhausting distraction.  But Trump has consistently asserted that climate change is "fake news". 
            Climate change has been erased from official documents and websites; down the Orwellian memory hole.  No proposals for climate change research grants will be considered for funding.  Republican controlled states have prohibited the phrase "climate change".  But the real world is unaffected by foolish ravings of addicts in denial.
            For 800,000 years, through multiple ices ages, atmospheric CO2 concentrations ranged between 180-280 ppm (parts per million).  In the last ice age, New York state was covered with three miles of ice.  A 100 ppm increase in CO2 warmed the planet to our current climate, about twelve thousand years ago.  CO2 has risen another 120 ppm in 150 years, a level last seen 4 million years ago, when sea levels were 200' higher.  A few years ago, science discovered that 90% of this recent heating had entered the ocean, warming the top half mile of the oceans.  We are beginning to witness the consequences. 
            When oceans get too warm, the symbiotic plankton in corals fail to perform and get rejected.  If oceans cool quickly enough, coral can recover; if not, they die, leaving bleached white skeletons.  In 2016, persistent warming killed more than a quarter of Australia's Great Barrier Reef.  Much of the rest of the world's coral, which support a quarter of ocean life and feeds billions of humans, was also affected.  Along our coast, warmer water has killed urchin predators, and the resulting urchin population explosion has devastated the kelp, the foundation of the local ocean food chain.
            Warmer oceans affect Arctic sea ice.  In November 2017, the temperature at the North pole was just below freezing, 40-50° warmer than usual.  Arctic ice normally lasts many seasons, getting thicker as wind crunches the sheets into dense ridges, which can last through the summer.  Now most of the sea ice is one year ice, which melts more quickly during the summer.  Much of the Arctic is ice free in late summer, and transpolar shipping has increased.  As summer water temperatures increase, there is concern about a catastrophic release of seafloor methane, which could produce a sharp temperature spike over a decade.
            Arctic warming is contributing to the slowing of the Meridional Overturning Circulation (MOC), a global ocean circulation system which includes the Gulf Stream.  The MOC is driven by a down welling of cold, dense, salty water flowing from the Arctic basin south of Iceland.  With a warming planet, the entire surface of Greenland is melting in summer, adding massive amounts of fresh water, which is less dense than salty water.  This fresh water infusion, and the general warming of the Arctic, has diminished the MOC down welling rate by 15% over the last half century.  The geologic record shows the MOC has stalled in the past, which created a radical change in world climate.  Europe was much colder than now.
            At the south pole, the warming ocean is destabilizing Antarctic glaciers.  These glaciers flow down to the sea and ground on the ocean floor miles off shore, impeding further downward ice flow.  Warmer water is melting them from below, eroding the grounding line, and speeding the flow of ice off the land.  Unlike Arctic ice melt, Antarctic ice melt raises sea level, as does ice melting off of Greenland.  In addition, warmer water expands, further contributing to sea level rise.
            Miami is spending over $400 million dealing with "persistent sunny day flooding".  Norfolk, Virginia, home to the world's largest naval base, is facing similar expenditures.  Republicans ignore this information, concerned that acknowledging climate change would lead to increased government regulations.  However, they seem content with corporations regulating everything, which is why we are in this mess.  Oil companies knew in the 70s that consumption of their product would endanger the entire planet, and hid the evidence to maximize their profits.  If they had been good planetary citizens then, there would be no need for government action now.