Almost unbelievable by today’s standards, global cooling in the 70’s caused speculation that the Earth’s surface and the atmosphere were heading to a period of extensive glaciation. This hypothesis had support in the scientific community and gained temporary popular attention due to a combination of a slight downward trend of temperatures from the 1940s to the early 1970s. I had a friend who was a climatologist. and he had me convinced that the thickness of the ice that once covered the Valley would do so again someday. Some people were nearly as concerned about another ice age as we are about global warming today.
Scientists too, discovered that there has been a decline of sunlight reaching the Earth; known as global dimming. But according to a paper published in the journal ‘Science’, the dimming did not continue into the 1990s and indeed ever since the 1980s scientists have observed a widespread brightening
Aerosols, the fine particles in air pollution, reflect a small portion of sunlight back into space and, thus, actually help keep global warming in check. That’s true despite the carbon dioxide emissions coming from the same smokestacks that warm the planet.
Slashing sulfur dioxide pollution and aerosols in the United States and Europe over the past decades counts as one of the biggest environmental success stories. Then the Clean Air Act came into effect that would add more than a year of life to the average North American. But by decreasing this pollution came an unintended and unexpected consequence – a warming planet.
$$$$Global warming doubters now like to point to fears of global cooling in the 1970s as proof that climate scientists can’t get their story straight. The majority of climatologists agree that this assertion is entirely wrong. Concerns in the 1970s and predictions around global cooling were correctly based on the cooling power of aerosol pollution but that was then.
Some scientists have suggested using aerosols to stave off the effects of global warming as an emergency geoengineering measure to cool the planet by creating a haze. The simplest solution would be to emit more sulfates which would end up in the lowest part of the atmosphere. This idea sounds like a back-handed one to me.
Exactly two centuries ago this summer, it was winter. A major volcanic eruption had a cooling effect on the climate leading to the “Year without a Summer.” Below-freezing temperatures killed crops throughout the Northeast, forcing thousands of farmers to uproot and move west in search of warmer pastures. In Europe, the cold air was wetter and soaked the continent for more than 120 days of its summer.
To investigate a possible solution to putting the brakes on global warming, there was a scientific global pursuit of clues left from a massive volcanic eruption that had a devastating impact on the Earth 75,000 years ago. The destructive power unleashed by the super volcano went far beyond that of any eruption in recorded human history, an event thought to have unleashed fire, famine, and death upon a quarter of the globe. When a volcano erupts, it spews forth lava, gas, and smoke, filling the skies with sulfur. Those clouds of sulfur reflect more of the sun’s solar radiation back into space and away from Earth, which has a cooling effect on the planet. The scientific research proved that an intervention of mimicking a volcanic eruption might be the approach needed to stave off disaster.
Climate engineering, commonly referred to as geoengineering is the deliberate large-scale intervention in the Earth’s natural systems to counteract climate change with the aim of affecting adverse global warming. Ongoing experimentation of introducing sulfates into the atmosphere and/or creating a man-made volcano seem farfetched but one of these or some other mind-boggling version may be necessary to prolong the existence of mankind from the effects of global warming. Given the uncertainties and stakes involved, it is imperative that adequate research determine if any of the proposed geoengineering techniques could be employed without creating countervailing side-effects.
It is far from certain that any of them could be, so it would be extremely unwise to bank on geoengineering as a ‘silver bullet’ for climate change.
