On climate change the White House appears open to hosting fresh air cool-headed debates that separate science from sanctimony. The new EPA director, Scott Pruitt, advocates peer-reviewed investigations of facts and fictions regarding key areas of agreement and dispute.
Don’t be surprised to learn that overall, there are more areas of general agreement than contention. First, no one I know disputes that the global climate has been warming over the past century and a half, that sea levels have indeed been rising, or that human activities, including carbon dioxide emissions, have and will continue to contribute “some influence.”
The big contentions have to do with determining just how much influence, and why should we should truly care? Repeatedly failed attempts to match actual observations with modeled theories demonstrate that the science is clearly not “settled” at all.
The planet is “supposed” to be getting warmer
Very fortunately, global temperatures have been rising since the end of the last in a series of 90,000-year-long Ice Ages about 12,000 years ago. Temperatures were at least as warm about 2,000 years ago when Christianity arose during the “Roman Warm Period.” They were also about the same as current temperatures during the “Medieval Warm Period” about a thousand years later when followers of Erik the Red raised sheep and goats on southwestern Greenland’s coastal grasslands.
Global temperatures began warming again following a much shorter “Little Ice Age” which lasted from about 1350 until shortly after General Washington’s troops spent a brutally cold winter at Valley Forge in 1777, and Napoleon’s beat a brutally frigid retreat from Moscow in 1812. That subsequent warming which began before the Industrial Revolution may very likely continue in fits and starts until the next Ice Age.
Still, U.S. temperatures between 1910 through the mid-1940s were warmer than now, and then cooled again for about three decades following World War II industrialization which added a lot of CO2 to the atmosphere. Then following a decade of warming, temperatures have since been statistically flat over the past nearly two decades.
Natural warming releases more CO2 into the atmosphere
Today’s atmospheric 400 ppm (parts per million) CO2 levels are actually very low compared with the 2,000 ppm that existed during periods when life flourished throughout much of Earth’s history. Naturally warming periods release dissolved ocean CO2 into the atmosphere, just as unrefrigerated carbonated drinks do.
Only about 3% of those four out of every 10,000 atmospheric CO2 greenhouse gas molecules have been added by humans. Mother Nature, including her decaying plants and volcanoes, puts about 20 times more CO2 into the atmosphere daily than all human industries contribute.
Warmer periods with higher atmospheric CO2 support agriculture
Warm climate periods equate to longer growing seasons, and higher atmospheric CO2 fertilization levels make them greener. A global satellite study published in the April 2016 edition of the journal Nature reported “a persistent and widespread increase” of CO2 fertilized greening over 25% to 50% of the “global vegetated area” over the past 35 years.
Of the 85% of Earth’s ice-free lands, the areas covered in green average about 32% of that amount. The additional vegetation laid out in a carpet would cover the continental U.S. twice over.
Sea levels have been rising at the same rate for centuries
Sea levels which rapidly rose 400 feet following the last Ice Age have only risen at a steady rate of four to eight inches per century over the past 150 years. There has been no significant sea rise acceleration over the past 50 years despite rising atmospheric CO2 levels.
Even according to the latest of all unfailingly alarmist UN Intergovernmental Panel on Climate Change (IPCC) reports, “It is likely that GMSL [Global Mean Sea Level] rose between 1920 and 1950 at a rate comparable to that observed between 1993 and 2010.”
As for future influences of melting glaciers, consider that the Arctic, which goes through regular 60- to 70-year-long warming and cooling cycles, has most recently been losing some ice mass, while most of the vastly larger Antarctic continent has been gaining.
A National Academy of Sciences report attributes a primary cause of those thunderous West Antarctic Ice Sheet iceberg collapses we often see featured in the media to geothermal heat from seabed volcanoes below. This coastal melting has been operating at time scales of hundreds to thousands of years.
No responsible person can claim to predict future temperatures
Theoretical computer climate models have been consistently wrong for more than 30 years . . . overwarming global temperatures compared with actual satellite measurements by a factor more than twice higher. Even IPCC’s 2001 summary assessment report conceded that “The climate system is a coupled non-linear chaotic system, and therefore the long-term prediction of future climate states is not possible.”
Don’t even think of buying a used car from anybody claiming that they can.