Jim Steele/Planet in the Balance
The earth’s energy equilibrium is determined by the balance between incoming solar radiation versus radiative cooling that emits infrared radiation back to space. Water vapor primarily and CO2 can slow radiative cooling via the greenhouse effect. I’m most grateful for the greenhouse effect. Without it the earth’s average temperature would hover near 0°F instead of our currently more livable 59°F. But in addition, the earth’s global average temperature is determined by a variety of climate dynamics, such as the balance between ocean heat storage and heat ventilation. Scientists attributed the slowdown in 21st century global warming to increased ocean heat storage. Warming in the northeast Pacific Ocean, famously known as the blob, was not caused by added heat, but by reduced winds that ventilated less heat than normal. Although increased cloud cover can slow the loss of outward bound infrared radiation, clouds also block sunlight to cause more cooling.
Changes in land surface conditions are another critical dynamic. For example, given the exact same amount of incoming heat, dry soils increase surface temperatures twice as fast as moist soils. As expanding human populations drained wetlands, and increasingly shunted rainwater into storm sewers, drier soils have caused abnormally higher temperatures during normally occurring droughts and heat waves. Unfortunately a myopic focus on CO2 has led to downplaying the vital importance of climate dynamics’ effect on global average temperature. But climate dynamics not only offer the best explanation for regional weather extremes, climate dynamics alone can account for 150 years of the earth’s average warming.
Consider that the polar regions are much warmer today than what the physics of radiative heating and cooling predict. Polar regions should be much, much colder because they radiate more heat back to space than is absorbed by the sun and the greenhouse effect combined. However dynamic transport of heat from the tropics via ocean and air currents adds to the Arctic “warmth” observed today. While winter temperatures (January) at north pole vary from 45°F to 15°F, the south pole winter temperatures vary between 80°F and 67°F. The south pole is so much colder because it is relatively shielded from the warming dynamics of ocean heat transport as well as its higher elevation.
Scientists have noted the warming effects of warm ocean currents travelling poleward for over 100 years. Winds extract heat from the warm poleward bound Gulf Stream and North Atlantic Current and carry that heat across the Atlantic to increase northwest Europe’s temperatures by 9-18°F. Thus it is the strength of those winds and the volume of heat carried by the ocean currents that determine changes in the average European temperature.
With comprehensive modern measurements, researchers now estimate inflows of warm Atlantic water “carry enough heat, if released, to melt the Arctic sea ice many times over.’
However, when that warm Atlantic water reaches the Arctic Ocean, most sinks below 300-foot depths due to its greater density caused by its higher saltiness. The dynamics of an overlying layer of fresh water and the thickness of insulating sea ice determine how much of that intruding Atlantic heat radiates back to space. Between 1950 and 1990, air temperatures exhibited a cooling trend over the western Arctic Ocean where insulating sea ice remained intact, inhibiting the ventilation of stored heat. Researchers concluded the cooling trend suggested no greenhouse effect.
Recent winddriven increases in the volume of intruding Atlantic water (as well as intruding Pacific water) have melted more Arctic sea ice. Additionally, the loss of sea ice has been driven simply by changes in the direction of the prevailing belowfreezing winds that push more ice cover out of the Arctic where it melts in the warmer Atlantic. Less ice ventilates more heat. The good news is less ice benefits the Arctic food chains. The loss of sea ice has increased photosynthesis and boosted the productivity of the Arctic Ocean food web three fold.
The complex interplay of those climate dynamics resulted in abnormally high Arctic temperatures regardless of any contribution from the greenhouse effect. Unaccounted for dynamic warming biases the global average temperature upwards but incorrectly gets attributed to rising CO2. Unfortunately as Mark Twain warned long ago, “All colleges have two great functions: to confer, and to conceal, valuable knowledge”. Accordingly despite copious published science by “climate dynamicists”, many scientists protect their pet theories and promote a manufactured CO2 driven “climate crisis” while downplaying the competing importance of natural climate dynamics. I have university colleagues who teach “global warming policy” without having examined the underlying science. Most journalists and politicians lack the needed scientific background and simply perpetuate the narrative because both profit from promoting crises. As a result, climate science is suffering, and the dynamic control knob of climate change gets veiled from the public.
(Jim Steele is Director emeritus of San Francisco State University’s Sierra Nevada Field Campus, authored Landscapes and Cycles: An Environmentalist’s Journey to Climate Skepticism, and a member of the CO2 Coalition. You can contact Jim Steele at email@example.com.)