According to a recent New Yorker article on the subject:
Geoengineering” actually refers to two distinct ideas about how to cool the planet. The first, solar-radiation management, focusses on reducing the impact of the sun. Whether by seeding clouds, spreading giant mirrors in the desert, or injecting sulfates into the stratosphere, most such plans seek to replicate the effects of eruptions like Mt. Pinatubo’s. The other approach is less risky, and involves removing carbon directly from the atmosphere and burying it in vast ocean storage beds or deep inside the earth.
Read more
http://www.newyorker.com/...
However, I believe there are a number of ecological design solutions that can be used to slow or reverse climate change. Unfortunately, they are not "heroic" engineering projects that will also change the color of the sky. Slow and steady biome restoration, household by household installation of efficient cookstoves, changes in diet and agriculture just don't have the panache of space umbrellas or pipelines to the clouds.
One organization which has consistently promoted ecological and systems design in response to climate change and other problems is the Buckminster Fuller Challenge and tomorrow in NYC they will announce their 2012 award winner
http://cooper.edu/...
Previous winners include John Todd's work on ecological remediation for the coal ravaged lands of Appalachia:
http://www.dailykos.com/...
and Allan Savory's work with grassland remediation using nomadic grazing methods:
http://www.youtube.com/...
This year's Fuller Challenge entries include
Living Building Challenge
https://ilbi.org/...
Living Building Challenge is a philosophy, advocacy tool, and certification program that addresses development at all scales. It is comprised of seven performance areas: Site, Water, Energy, Health, Materials, Equity, and Beauty.
Living Building Challenge defines the highest possible level of environmental performance, envisioning a built environment that is fully integrated with its ecosystem. It pushes the building industry to re-imagine business as usual, and it transforms building occupants from passive consumers into active stewards of increasingly scarce resources.
Eco-Fuel Africa Limited
http://www.ecofuelafrica.com/
Imagine a world where the poor no longer have to cut down forests for fuel, where poor farmers have access to free organic fertilizers, where poor people no longer have to die because of indoor air pollution and where young girls no longer have to drop out of school because they have to spend many hours in the field gathering wood for their families!
We work with rural farmers in Africa to make clean cooking fuel called gree charcoal and organic fertilizers called biochar from agricultural waste like coffee husks, sugarcane waste etc. Our green charcoal cooks as good as charcoal from wood, lasts longer, burns cleaner and is 20% cheaper than charcoal from wood. This is helping to stop deforestation, reduce indoor air pollution and reduce the amount of money poor people spend on fuel.
Water Retention Landscape of Tamera: A model for reversing desertification worldwide
http://www.tamera.org/...
The Water Retention Landscape is a model for natural decentralized water management, restoration of damaged ecosystems and disaster prevention. It is a basis for reforestation, agriculture and aquaculture, especially in regions threatened by desertification, and is an integral part of a comprehensive model for sustainability in water, food, energy and social structures.
Tamera is planned to become a Healing Biotope of plants, animals and human beings. Since the foundation of Tamera, the ecology team has planted more than 20.000 trees and started to create a water retention landscape. Food biotopes, garden terraces, raised bed cultures for future self-supply have been built, evergreen oases installed. "Edible landscapes", forest gardens, wet biotopes and water retention spaces were created. In the core of the ecological work is the natural water management.
The index of all the Buckminster Fuller Challenge entries:
http://challenge.bfi.org/...
Previous Related Diary:
Short Term Climate Forces: Black Carbon, Methane, and Tropospheric Ozone
http://www.dailykos.com/...