By William D. Balgord

Sometimes it’s helpful to step back and look at the big picture instead of the little details. As a geologist, I’m used to doing that.

This year, even before November was half spent, new minimum temperature and snowfall records had been set at hundreds of locations across the eastern United States.

In the 1970s, fears of global cooling made the cover of Time magazine. Those fears died a few years later because of a natural climate change. The “Great Pacific Climate Shift” brought warm equatorial water northward toward the Gulf of Alaska. Coupled with stronger El Niños, it increased seasonal temperatures across North America. That created new fears. Many people, including plenty of scientists, feared that global warming attributable to man-made CO₂ would melt the polar icecaps, initiating a runaway greenhouse effect.

In 1988, Dr. James Hansen of NASA’s Goddard Institute for Space Studies dramatically warned a Senate committee of imminent global warming triggered by carbon dioxide from the burning of fossil fuels. Rising global average temperature in the 1980s and 1990s seemed to validate his warning.

But since 1997-1998, there has been little demonstrable rise in global average temperature in the troposphere as measured by two reliable, independent satellite systems. Surface measurements still showed some warming, though slower than in the previous two decades. But they are influenced by land-use changes. The urban heat island effect, deforestation, and expanding infrastructure absorb heat energy by day on land surfaces and then release it at night to the atmosphere.

During the previous two winters, unseasonable incursions of polar air originating in faraway Siberia brought extreme cold across southern Canada into the United States. Climate scientists blamed it on an aberrant polar vortex. Snow fell on Charleston, SC, and remained on the ground for several days in early 2018.

The phenomenon is better explained as the result of massive cold, dry air settling in over Siberia in October, held in place by a stalled weather front for weeks before releasing into North America. Eastern Siberia is the source for the extremely cold air that tracks across northwest Canada into the Midwest and eastward, creating cold waves that reach South Carolina.

The world’s coldest temperatures occur routinely in northeastern Asia, not over the North Pole. The record for low temperature at any permanent settlement in the Northern Hemisphere belongs to Oymyakon, Siberia, which sank to ˗96.2°F in 1922.

This year’s early arrival of winter weather, some six weeks premature, cannot be attributed offhandedly to “global cooling.” As someone once reflected, “One swallow does not a summer make.” Neither does one blizzard a winter make.

Yet the popular idea that a steady increase in CO₂, thought to drive an irreversible rise in global temperature, would eventually render winter obsolete makes such untimely outbreaks of severe cold air surprising.

Only time will tell whether the warming trend of the 1980s and 1990s will resume or yield to cooling. Another five to 10 years may provide climate scientists with enough additional data to determine if CO₂ is actually the thermostat that controls global temperature. My own judgment (for what it’s worth) is that CO₂ is not the thermostat, but only one of a number of contributing factors, including major features of global geography.

The current positioning of the great land masses came about by slow continental drift. It favors the accumulation and preservation of snow and ice at high latitude and elevation from one winter to the next. It will remain so for many millions of years.

During earlier geologic times, when the continents were differently positioned, ocean currents flowed freely from the equator to the polar regions. That warmed them enough that vegetation and wildlife now common only to temperate and even tropical zones thrived even toward the poles. Now the current positioning of Antarctica, Greenland, North America, and Eurasia relative to the tropical oceans partially block that flow. Consequently, sufficient glacial ice remains, and cold ocean bottom water persists, to dampen temporary upward fluctuations in global temperature.

Consequently, I expect a continuation of the modest cyclical warming and cooling that have been the recurrent pattern throughout the 10,000-year interglacial cycle known as the Holocene Period. In due time another period of major continental glaciation may return to plunge exposed regions of the northern and southern hemispheres back into the deep freeze.

If a runaway greenhouse effect were even possible, it should have happened eons ago when CO₂ concentrations were some 20 times higher than at present. Since it did not, we can sleep peacefully tonight.

William D. Balgord, Ph.D. (geochemistry) is a contributing writer with The Cornwall Alliance for the Stewardship of Creation.