Cloud+Whitening

=Cloud Whitening (Cloud Reflectivity Modification)=

se gas emission reduction, the project aims to control global warming.
 * Cloud Reflectivity Modification**, also known as "Cloud Whitening," is an ** Geoengineering ** technique used to enhance the reflectivity of low clouds in order to manage solar radiations out of the earth. Low clouds are usually warmer and are highly reflective to sunlight, especially when it is white (due to the presence of small droplets) and therefore, brightening these clouds will increase the reflectivity, hence cooling the climate. Along with greenhou

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Basic Principles:
Clouds at lower levels cover about one-third of the ocean surface. Such clouds have ** Albedo ** levels of 0.3-0.7. and with that, the ** stratocumulus ** clouds yield a significant cooling effect in the planet. The longevity and cooling effects of the clouds can be increased by the enhancement of the albedo levels, which is done by spraying sea water (** NaCl **__)__ droplets that have approximately1μm in size. The production of ** cloud condensation nuclei **__,__ which i s done in order to brighten the clouds, can also be done with different chemicals such as soot and black carbon, however, spraying seawater from ships is the m ost effective method.

The Project:
In order to promote such effects on clouds, Stephen Salter from University of Edinburgh (UK), proposes the implementation of futuristic designed ships on the world's oceans. The professor affirms that 1,500 ships are necessary in order to accomplish marine cloud brightening, which would have to be utilized at the rate of 50 years if the world completely fails to lower CO2 emissions.

The so called "albedo yachts" would be controlled remotely and completely harmless to the environment: the project is wind-powered, and therefore able to generate sufficient electricity for its maintenance and thrust. They hold tall turbines that resemble traditional sailing vessels, and are designed such that its aerodynamics optimizes energy consumption, dealing with wind pretty much the ** same way a wing of an airplane does **. With that, the vessel is able to create a seawater haze of 1,000 meters into the atmosphere in a rate of 30 liters per second. Also, all of this will maintained by extremely complex softwares that controls the propellers, and are even able to handle sea storms. The project would cost between $3.2 to $4.8 billion if all 1,500 ships are installed, but the prices for repairs, maintenance and even the lifespan of the machine are still unknown.

Current Application:


As this is a developing technology, cloud whitening has still a long way to go financially. The world already invests in a variety of other environmental projects, and as a consequence, this type of Geoengineering still lacks supporters. However, the founder of Microsoft, Bill Gates, has donated $300,000 to Silver Lining, an American research body on the matter, but has already received criticisms. Specialists point out that his action is too risky, considering the uncertainty regarding the outcome of the trials, given that the project has only been tested through computer simulations. Furthermore, the ETC group mentioned the action was taken unexpectedly and suggested that it should not be done until the government sets regulations regarding the implementation of this new technology. Even so, Bill Gates' decision will represent the largest attempt to geoengineer the climate so far.

Opinions and questions to consider:
Just like any new project, cloud reflectivity modification is also very questioned. One of the debates is rather or not these new vessels should be constructed: the large fleet of conventional diesel-powered ships that sails across the ocean daily, could also be used to support the pumps. Some specialists also say the albedo boats are too expansive and that, as Nathan Myhrvold said, "All of these [geoengineering] ideas need a lot more work. Stephen [Salter] would be the first to say that." A large number of environmentalists also point out the fact that Geoengineering as a whole does not cut any human-caused pollution and carbon emission, meaning, it is only a way to cover up the human effects on nature. There is also a large room for future research on the seawater spraying project, considering that they might also be useful to produce frozen particles in areas affected by high ice melting and that charging sea water particles to utilize the Earth's electric field may be beneficial.

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Key Terms/Concepts:

 * Geoengineering:** Large-scale engineering or manipulation of the planetary environment, in this case, in reference to atmospheric chemistry.
 * Albedo:** The proportion of the incident radiation that is reflected by a surface.
 * Stratocumulus:** Lumpy layer of clouds that is characterized by weak intensity precipitation.
 * NaCl**:Sodium Chloride.
 * Cloud Condensation Nuclei:** Small particles (usually 0.2μm / 1/100th the size of a cloud droplet) that cloud droplets merge.
 * Airplane Wing Design:** Creates a vertical "lift" for dislocation.

**Bibliography:**
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Leonardo de Lucca Silva