Direct Air Capture
Painting Roofs White
- -Algae-Coated Buildings Touted as Climate Fix (CNet.com)
"Engineers envision that long plastic tubes, called photobioreactors, be integrated into building designs or retrofitted onto existing skyscrapers. Algae would grow from pumped-in carbon dioxide and sunlight and be harvested for use either as a liquid fuel to run in a combined heat-and-power unit or turned into biochar, or charcoal used as a soil conditioner that also sequesters carbon from the air."
"Finally, the institution says that buildings should be retrofitted with reflective roofs to deflect the sun's rays. In the past months, U.S. Energy Secretary Steven Chu has publicly touted this relatively low-tech approach, which was studied in-depth at the Lawrence Livermore Laboratory last year." 09-09
- -Asteroid Dust as Climate Fix (MSNBC News)
"The idea would be to place an asteroid at Lagrange point L1, a site where the gravitational pull of the sun and the Earth balance each other to keep an object in a relatively stable orbit. This point is about four times the distance from Earth to the moon."
"The researchers suggest outfitting a near-Earth asteroid with a 'mass driver,' a device consisting of electromagnets that would hurl asteroid-derived matter away from the giant rock. The mass driver could serve both as a rocket to push the asteroid to the L1 point and as an engine to spew out sun-shielding dust." 09-12
- -Geoengineering Requires Care (Wired News)
"The leader of the research, Hauke Schmidt of the Max Planck Institute, Germany, believes their experiment still contributes important details on how the Earth’s systems might respond to geoengineering. 'The first thing we realized was that we had to ‘dim’ the sun 25 percent more than expected, in order for the Earth’s systems to show a response, which translates to needing more geoengineering than previously thought,' says Schmidt." 09-12
- -Geoengineering: Not Safe AND Affordable (ThinkProgress.org)
"Not putting CO2 in the air is much less risky and vastly cheaper than trying to pull it out later." 02-15
- A Solution for Melting Methane in Oceans (ClimateCoLab.org)
Provides a geoengineering plan for "Testing nontoxic chemicals that stabilize methane ice, making it stable and resistant to elevated temperatures as the climate warms." 07-15
- Cloud Whitening (Wikipedia.org)
"Engineer Stephen Salter wants to build massive 'cloud-whitening' towers in the Faroe Islands or on islands in the Bering Strait in order to keep Arctic temperatures from climbing."
"If temperatures continue to climb as they are, the Arctic could be totally ice-free every September within the next few years. Regional ice melt would not only cause sea levels to rise, it could trigger a release of the crap-ton of methane currently trapped beneath the Arctic sea bed. And since methane is a greenhouse gas even more potent and scary than carbon dioxide, failing to prevent said sea ice melt might exacerbate global warming." 03-12
- Cool Roof (Wikipedia.org)
"In the world of industrial and commercial buildings, a roofing system that can deliver high solar reflectance (the ability to reflect the visible, infrared and ultraviolet wavelengths of the sun, reducing heat transfer to the building) and high thermal emittance (the ability to release a large percentage of absorbed, or non-reflected solar energy) is a cool roof. Most cool roofs are white or other light colors." 09-09
- Cool Roof Materials and Colors (Solar-Estimate.org)
"If you're replacing the whole roof deck, you can easily install radiant barriers at the same time. In fact, there's a radiant barrier currently on the market that's attached to plywood. You can use it in place of standard decking, with the aluminum foil facing down into the attic. The material doesn't cost much more than standard decking, and the installation process is the same, so there is no extra labor involved. In very hot climates this is a sensible, cost-effective, and easy retrofit."
A bright white coating (ceramic, elastomeric) on a smooth surface can increase solar reflectance to 90%, limiting the rise in temperature of the roof by 15 degrees over outdoor temperature. Black shingles, in contrast, provide 5% solar reflectance and can allow the roof temperature to rise 90 degrees over outside temperature. 07-11
- Four Geoengineering Plans (PopularMechanics.com)
"This past year, three European institutions released reports on the benefits and risks of “climate engineering.” Recommendations vary, but the reports each conclude that the most promising technologies should be tested on small scales. Scientists worry that some nation’s future unilateral geo-engineering project could cause frightening side effects that cross national boundaries." 08-11
- Geoengineering (Wikipedia.org)
"The modern concept of geoengineering is usually taken to mean proposals to deliberately manipulate the Earth's climate to counteract the effects of global warming from greenhouse gas emissions. The National Academy of Sciences defined geoengineering as 'options that would involve large-scale engineering of our environment in order to combat or counteract the effects of changes in atmospheric chemistry.' " 
"Some geoengineering techniques are based on carbon sequestration."
"Typically, the scientists and engineers proposing geoengineering strategies do not suggest that they are an alternative to emissions control, but rather an accompanying strategy." 09-09
- Geoengineering Against Climate Change: Five Methods (BBC News)
"Some scientists and engineers are proposing radical, large-scale ideas that could save us from disaster."
Editor's Note: One of the most popular methods of geoengineering, sequestration of carbon through use of biochar, was not mentioned. It became popular after the article was released in early 2007. 04-10
- Geoengineering Alternatives (IPSNews.net)
"The geoengineering proposals include installing giant vertical pipes in the ocean to bring cold water to the surface, pumping vast amounts of sulphates into the stratosphere to block sunlight, or blowing ocean salt spray into clouds to increase their reflectivity."
"Broadly speaking, there are two main geoengineering approaches: solar radiation management and carbon sequestration, in other words, absorbing carbon dioxide from the atmosphere to reduce the concentration of this greenhouse-effect gas."
- Geoengineering Conclusions (HomelandSecurityNewsWire.com)
"Geoengineering approaches would succeed in restoring the average global temperature to "normal" levels, but some regions would remain too warm, whereas others would 'overshoot' and cool too much; in addition, average rainfall would be reduced."
"The work, however, does offer some way forward. Co-author Dan Lunt added: 'Our simulations indicate that it might be possible to identify a strength of geoengineering capable of meeting multiple targets, such as maintaining a stable mass balance of the Greenland ice sheet and cooling global climate, but without reducing global precipitation below normal amounts or exposing significant fractions of the Earth to unusual climate conditions.' " 09-10
- Geoengineering Conclusions (ScienceDaily.com)
"Key findings include:
-Enhancing carbon sinks could bring CO2 back to its pre-industrial level, but not before 2100 – and only when combined with strong mitigation of CO2 emissions
-Stratospheric aerosol injections and sunshades in space have by far the greatest potential to cool the climate by 2050 - but also carry the greatest risk
-Surprisingly, existing activities that add phosphorous to the ocean may have greater long-term carbon sequestration potential than deliberately adding iron or nitrogen
-On land, sequestering carbon in new forests and as ‘bio-char’ (charcoal added back to the soil) have greater short-term cooling potential than ocean fertilisation." 09-09
- Geoengineering Methods and Need (The Royal Society)
Focuses on distributing particulates from jets.
- Geoengineering by Seeding Clouds (Time.com)
"This week, another of the perennials got a good, close look when a study by the Carnegie Institution and the Indian Institute of Science explored the idea of seeding clouds to make them whiter and more reflective—essentially the mirror idea but without the actual mirrors. The good news: It works! The bad news: You'd better like monsoons." 06-10
- Geoengineering: A Short-Term Delay for Climate Change? (Time.com)
"Under a plan currently being developed by Nathan Myhrvold's Intellectual Ventures, sulfur dioxide would be pumped up a 25-km-long pipe suspended by high-altitude balloons, then sprayed out into the stratosphere. Myhrvold, formerly Microsoft's chief technology officer, says just one such pipe less than a foot in diameter could do the job for the entire northern hemisphere — at a cost of less than $1 billion. More research is needed, however, to establish the technology's ramifications, including its effects on ozone levels."
"An even more promising solution is something called marine cloud-whitening. The idea is that if you fill the air with tiny particles around which water vapor can condense, you'll get denser, whiter clouds that will reflect more solar energy back into space, thus cooling the planet."
"SAI and marine cloud-whitening are just two of many possible geoengineering projects. Others range from putting giant mirrors in space to planting billions of trees. What they all have in common is the potential to have a large and immediate impact on global temperatures at relatively low cost. None represent any kind of permanent solution to climate change." 11-10
- The Egg Shell Geoengineering Solution (Time.com)
"According to a study in the International Journal of Global Warming led by Basab Chaudhuri of the University of Calcutta, the membrane of an eggshell can absorb almost seven times its weight in carbon dioxide—and once the gas is trapped, it can be stored.