2009-2011
The modern concept of geo-engineering (or climate engineering) describes deliberately manipulating the Earth's climate to counteract the effects of global warming from greenhouse gas emissions.
The geoengineering of Earth's climate systems is achieved through two primary ideologies, Solar Radiation Management (SRM) and Carbon Dioxide Removal (CDR)
1-Carbon Dioxide Removal (CDR) and sequestration. This is artificial trees, ocean fertilization etc. These projects are declassified for the most part.
2- Solar Radiation Management (SRM), controlling sunlight before it reaches the planet.
A- Stratospheric Aerosol Geo-Engineering (SAG-SRM) is the artificial modification of Earth's climate systems using reflective nano-materials (aerosols) to reflect sunlight. The aerosols are dispersed via jet aircraft trails that expand into reflective artificial clouds.
The reflective material of choice is aluminum.
Of course, like any planetary-scale project dealing with the complex climate system, there is a non-trivial risk of unintended consequences.
more info:
http://www.countercurrents.org/murphy030310.htm
http://geoengineeringwatch.org/
