Geo-Engineering a Climate Change Solution

Geo-EngineeringThe deliberate large-scale manipulation of the planetary environment to counteract anthropogenic climate change

The Royal Society, “Geo-engineering the Climate” 2009

Geo-Engineering: Basic Principle

• Introduce particles into the atmosphere which reflect more of the incoming solar radiation (energy from the sun)

• As energy is reflected (instead of being absorbed) the earth’s atmosphere cools

Idea From Nature: Volcanoes

Large eruptions release great amounts of ash and gas into the atmosphere

Krakatoa, Indonesia (1883)Pinatubo, Phillipines (1991)– 20 million tons of sulfur dioxide (SO2) gas released

•These eruptions caused measurable decreases in the global climate for 1-3 years.– 1.3 degrees Celsius cooler

Volcanoes and GHG Emissions• CO2 emissions from ALL active volcanoes in one

year0.25 Gigatons CO2

• Human-caused CO2 emissions for 201035 Gigatons CO2

Humans produce 140 times as much CO2 than all active volcanoes in one year

Volcanoes are not a significant source of CO2

Proposed Process• Planes, Balloons, Rockets and/or Artillery deliver

sulfur dioxide (SO2) gas into the upper atmosphere

• SO2 reacts with water vapour and forms sulfuric acid

SO2 + H20 H2SO4

• Super-small droplets (aerosols) of sulfuric acid reflect incoming solar radiation back into space

• Sulfur aerosols remain in atmosphere for 3-4 years

Benefits• Low cost– SO2 easy and cheap to produce

• Delivery technology exists– Planes, balloons, rockets etc.

• Likely to be very effective at cooling climate

• Could be implemented quickly

Concerns• Health concerns when sulfuric acid falls from

atmosphere

• Impact of acid precipitation on water cycle

• Less solar radiation reaching surface– Negative impact on photosynthesis– Solar energy panels less effective

Geo-Engineering Debate