Geo-engineering is the science and technology of altering the earth’s climate through human intervention. The possibility of geo-engineering the climate was first considered in the 1830s. During World War II, this technology began to be developed, although for military purposes. Since then, several different methods for intentionally altering the climate for ecological reasons have been proposed. These technologies remain controversial, posing both potential benefits and harm.
Reasons for Geo-Engineering the Climate
Industrialization has led to an increase of carbon dioxide in the atmosphere that most scientists believe is causing an increase in global temperatures and altering climate. Documented climate changes include droughts, increased air and sea temperatures, melting ice caps, and more unpredictable weather patterns.
Reducing carbon dioxide levels through lowering of emissions has been a major focus in the effort to counteract this trend. Geo-engineering is a separate approach that seeks to reduce the effects of carbon dioxide in the atmosphere through direct intervention with natural systems.
Methods of Geo-Engineering
The major methods of altering the climate proposed by scientists include injecting particles into the atmosphere, adding iron particles to the ocean, installing reflective devises into space, and using reflective terrestrial materials like light colored roofing and large acreage of light colored plants.
Investigation of major volcanic eruptions has found that sulfur from volcanic eruptions changes the climate and reduces temperatures. Based on this observation, some scientists have suggested intentionally injecting sulfur particles into the stratosphere that would reflect sunlight, leading to cooling of the planet. The long term effects on plant and animal life from an increase of sulfur in the air, water, and soil are unknown, and the cost could be enormous.
Pumping iron particles into the ocean could nourish algae that would in turn consume carbon dioxide and sink it to the bottom of the sea. These algae blooms could adversely affect ocean life in ways that are impossible to predict. The effects of massive amounts of carbon sequestered on the ocean floor is also unknown.
Reflective space mirrors are another high cost geo-engineering possibility. The downside is that space vehicles damage the ozone layer each time they pass through it, and t would take a large amount of space mirrors before any benefit could be seen on earth. The costs and potential harm of this approach could outweigh the benefits.
Reflective roofing materials are a solution that only involves changes in roofing methods. Light colored roofs reflect heat and light back into space, reducing warming of the building, leading to lower air conditioning energy consumption, and lowering of ground temperatures around the building. This is a passive form of geo-engineering that may be the easiest and least costly to implement.
Planting huge forests of artificial, light-colored trees or other plants is another way of reflecting heat back into space. However, these crops would take up growing space that might otherwise be used for farming food. The materials used in making artificial plants for this purpose may in themselves require industrial production methods that would offset any potential benefit.
Carbon Emission Control
Some argue that any form of geo-engineering will make people think that there is not as much need for controlling carbon emissions in the first place. They argue that if large-scale, expensive geo-engineering projects become common, governments and corporations will have less incentive for making low carbon emission vehicles and factories. At this point, geo-engineering to control the detrimental effects of human made carbon dioxide remains a controversial idea with unpredictable consequences.