Outrageous, Alarming, and Evocative of Science Fiction: Why We Need Geoengineering
By: Madison Hunter
Tags: Climate Change, Science, Geoengineering, Global Warming, Environment

The case for geoengineering.

A strong case in favor of geoengineering isn’t something that began in the late 2000s when we discovered that we had a global warming problem. Instead, it began long before that.

In 1841, an American meteorologist by the name of James Pollard Espy published a book in which he postulated that by generating large storms, “rain might be produced artificially in time of drought”. He was neither the first nor the last. From then on, ideas about geoengineering ranged from the concerning to the politically charged, to not half-bad ideas.

For instance, in 1908, Svante Arrhenius suggested that by adding carbonic acid to the atmosphere, global warming would occur, resulting in people being able to enjoy the benefits of a warmer climate. That sure didn’t age well.

In 1932 and 1946, the Soviet Union and the United States respectively undertook studies surrounding cloud seeding as a method of altering the weather. As politically charged as this era was, some great technology came out of it, including the capacity to change the weather on a small scale using cloud seeding technology.

More recently, Dr. Edward Teller, known as the “father of the hydrogen bomb”, became a supporter of two methods of geoengineering that increase the albedo of the planet. In short, albedo is the built-in cooling mechanism of the planet. The polar ice caps are a great source of albedo (or, whiteness), as the snow and ice reflect sunlight into space. However, because of their fast melting rate, Dr. Teller proposed two other methods of increasing planetary albedo. The first, and most simple, is to send small particles into the atmosphere that will act to scatter and reflect sunlight. The second, and more expensive and technologically difficult, would be launching mirrors into space to reflect sunlight.

The first of Dr. Teller’s proposed methods have been extensively discussed and modeled by scientists. The theory behind this method comes from global dimming (cooling) that is associated with major volcanic eruptions.

The famous eruption of Mount Pinatubo in 1991 is the perfect case study for global dimming. During the eruption, 15 million tons of sulfur dioxide were added into the stratosphere. Once in the stratosphere, the sulfur dioxide reacted with water to form aerosol particles that were made up of sulfuric acid droplets. Over several years, winds spread the particles around the world. The particles remained in the stratosphere for years due to the stratosphere not having any rain clouds to wash away the pollutants. Over time, the pollutants were slowly removed by chemical processes and atmospheric circulation. The important thing to gather here though is that these particles, once in the atmosphere, contributed to the deflection of sunlight, resulting in a global drop in temperature of approximately 0.6 degrees Celsius (1 degree Fahrenheit).

Because of this eruption-caused drop in global temperature, the theory remains that by adding sulfates into the stratosphere, the resulting buildup of particles would act to deflect solar radiation as it tries to reach Earth. This would mimic massive volcanic eruptions and the Earth would cool.

However, the addition of particles to the stratosphere to keep sunlight out could have a serious impact on weather systems. Once released into the stratosphere by specially equipped planes, little can be done in the way of evenly distributing the particles. An uneven distribution could affect regions differently, causing potential changes in rainfall patterns and ocean circulation patterns. As you might have guessed, this can affect regional temperatures and precipitation levels. Furthermore, there is little known about the impact of the aerosol particles on human health and the environment once they begin to leave the stratosphere.

Another method of geoengineering is to remove greenhouse gases from the atmosphere. This can be done through several methods, including using devices to extract carbon dioxide from the air and seeding oceans to produce more carbon-absorbing algae.

Using devices to extract carbon dioxide from the air works on the theory that the captured carbon would be turned into biomass that would power these carbon-harvesting systems. The result would be net-zero emissions. The problem with this method is that the amount of land required for these systems would be enormous. Furthermore, fuel would have to be provided to the machines initially, before they could become self-sustaining using the carbon they pull from the atmosphere.

However, instead of planting trees to feed into these machines as biomass in order to pull carbon dioxide and other greenhouse gases from the atmosphere, couldn’t we just plant trees instead? Trees are the ideal, and most efficient greenhouse-gas-extraction-device, aren’t they? Also, wouldn’t trees be cheaper, easier to maintain, and take up less space than an entire building full of machines dedicated to removing carbon dioxide from the atmosphere?

Basically, yes.

Therein lies the tried-and-true method of geoengineering that has been around for millions of years. Right under our noses.

Restoring forests has all of the benefits on the same scale as geoengineering without any of the potentially negative effects. According to an article in the Proceedings of the National Academy of Sciences of the United States of America, “natural climate solutions can provide 37% of cost-effective CO2 mitigation needed through 2030 for a >66% chance of holding warming to below 2 degrees Celsius.” The paper defines natural climate solutions as being various “conservation, restoration, and improved land management actions”. These actions would result in improving carbon capture by the soil and plants and the reduction of greenhouse gas emissions found in various natural locations. This more natural method of geoengineering has a list of positive side effects that go along with it, including “water filtration, flood buffering, soil health, biodiversity habitat, and enhanced climate resilience.”

Forest restoration wouldn’t need a significant replanting effort either. Forests restore themselves naturally, and by allowing multiple species of trees to grow in an area instead of planting “crops” of trees, forests would grow healthier and stronger and would be much more capable of pulling carbon dioxide out of the atmosphere.