Geoengineering: 3 Novel Ways To Artificially Alter The Climate

  • One geoengineering method involves spraying sulfate aerosols into the atmosphere to reflect away sunlight.
  • Another solar geoengineering method involves brightening clouds above the oceans, causing the clouds to reflect away more light before it can be absorbed by the dark oceans below.
  • Carbon capture requires extensive investments for it to be effective on a global scale.

Global temperatures are currently increasing at a faster clip than at any time in the last 2 million years. This has fueled record-breaking heat waves, wildfires and droughts, and has also intensified weather patterns.

Scientists have repeatedly declared that the best way to slow climate change is by cutting back greenhouse emissions by switching to low-carbon energy sources like solar and wind; however, a growing number of countries are exploring geoengineering, the large-scale modification of Earth’s climate, as a faster way to alter the climate or reverse the effects of climate change. Here are 3 novel ways to artificially change the climate

Giving Earth Some Shade

Heavy emissions of CO2 and other potent greenhouse gasses such as methane are responsible for the pronounced greenhouse effect afflicting our planet i.e. an increase in the amount of sunlight that the earth absorbs. To counter this, several methods have been proposed to reduce the amount of sunlight reaching the surface of the earth aka solar geoengineering.One method involves spraying sulfate aerosols into the atmosphere to reflect away sunlight. Sulfate aerosols are produced by burning fossil fuels and also released naturally from volcanoes and desert dust. Sulfate aerosols released by fossil fuel combustion typically remain close to the ground and cause dangerous levels of air pollution; however, scientists are now experimenting with releasing these tiny particles into the stratosphere using airplanes or hot air balloons, where they can effectively increase sunlight reflectance. The biggest advantages of this method are relative cost-effectiveness, speedy application and reversibility. Additionally, scientists are well accustomed to sulfate aerosols since they already exist in the atmosphere. However, their biggest drawback is that sulfate aerosols could initiate ozone-destroying reactions, allowing more harmful ultraviolet rays to reach the Earth. Further, carrying out the exercise on a global scale would need aircraft to ascend to 60,000 feet [around 18km]–twice the typical altitude of conventional jets. Thankfully, scientists are confident that building aircraft that can reach those heights is feasible. Currently, the technique might work with conventional aircraft in the Arctic because the stratosphere is lower there.

Another solar geoengineering method involves brightening clouds above the oceans, causing the clouds to reflect away more light before it can be absorbed by the dark oceans below. To achieve this, tiny seawater aerosols could be sprayed over the oceans, so that smaller cloud-forming droplets can stick to them (a cloud’s brightness depends on the size of water droplets that form it). However, cloud brightening comes with a greater risk of affecting weather patterns than spraying sulfate aerosols since clouds typically form in the lowest level of the atmosphere known as the troposphere.

Artificial Rain-Making

The Middle East is regarded as one of our planet’s greatest energy hotspots thanks to an abundance of fossil fuel resources and ample solar radiation. Unfortunately, rain is a scarce resource in this dry and arid region, with annual precipitation ranging between 350mm to 750 mm. Rainfall is especially sparse and inconsistent in Saudi Arabia and the UAE, where the long-term average is below 100 mm per year. To supplement their limited water resources, these countries have invested heavily in desalination plants, underground aquifers and a novel rain-making technology: cloud seeding. They are hardly alone: as many as 50 countries including China, India and Russia, have carried out cloud seeding operations.

Cloud seeding dates back to more than half a century, and typically involves sending up an aircraft that fires flares that release particles of sodium chloride (in warmer areas) or silver iodide (in colder parts of the world). These tiny particles act as condensation nuclei around which ice crystals coalesce before falling as precipitation in the form of rain or snow. It’s estimated that cloud seeding can increase rainfall by 30-35% in drier atmospheric conditions and up to 10-15% in more humid environments. China, India and Russia.

Direct Carbon Capture

Direct carbon capture is an umbrella term used to describe a variety of chemical processes used to filter CO2 from the air, which is then stored underground or funneled to be used to make consumer goods. Carbon capture not only addresses the root problem of excess atmospheric CO2  but also presents fewer risks than the other climate-altering technologies. 

Thankfully, carbon capture is quickly becoming an everyday reality and has already facilitated the growth of a market for carbon trading with companies such as ClimeworksCarbon Engineering Global Thermostat, and  CarbonCure working to commercialize their technologies. 

However, carbon capture requires extensive investments for it to be effective on a global scale. Scientists have estimated that we need to capture as much as 10 gigatonnes of CO2 per year by the middle of the century for this technology to be effective. To give you some perspective of the task ahead, Climeworks, one of the biggest operators in the sector, is only able to capture ~4,000 tonnes of CO2 each year. MckInsey estimates that we need to build as many as 700 carbon capture, utilization and storage (CCUS) hubs globally, located on, or close to, potential storage locations and Enhanced Oil and Gas Recovery (EOR/EGR) sites, nearly 50 times the current global fleet of just 15 hubs.Thankfully, Big Oil has begun investing heavily in CCUS. Last year, Exxon Mobil Corp. (NYSE:XOM) CEO Darren Woods predicted that the company’s new Low Carbon business has the potential to outperform its legacy oil and gas business and generate hundreds of billions in revenues.Meanwhile, oil field services giant Schlumberger Ltd (NYSE:SLB) has created the SLB New Energy unit encompassing carbon solutions including CCUS, hydrogen, geothermal and geoenergy, energy storage and critical minerals.  SLB New Energy President Gavin Rennick estimates the new segment will hit $3 billion by the end of the current decade and exceed $10 billion by the end of the next decade. Of these new energy businesses, Rennick says CCUS is the fastest growing opportunity thanks to the U.S. Inflation Reduction Act (IRA).