Haze

Haze is a product of photochemical smog and is brown/yellow colored.
Its distribution ranges from urban areas to the grand canyon.

Its composition is moslty organic carbon and sulfate, there is also ammonium and nitrate, and nitric acids nuetralized to salts. the particles are sized 0.4-0.8 in diameter (about half that of the wavelegneth of light)

It affects the atmosphere by reducing visual clarity and and scattering the light able to hit the ground.

This link shows a picture of a landscape corrupt with Haze:

http://altered-dimension.deviantart.com/art/Atmospheric-Haze-129737820

Acid Rain

Acid rain is a serious environmental problem that many regions face. This genetic term covers many areas including acid, fog, snow. Each corresponds to atmospheric percipatation of heavy acidity.

Acid rain was discovered by Angus Smith in Great Britian in the mid-1800's.

The term specifically refers to percipitation that is more acidic than normal rain (or unpolluted rain)
-the mild acitidy comes from atmospheric carbon forming carbonic acid.

ex. CO2 + H20 <---> H2CO3 (partially ionizes H+, lowering pH)

This video depicts acid rains effects on east coast cities (esp wash DC) to view the upclose effects on structures such as the capitol building.

http://www.bing.com/videos/watch/video/acid-rain-eating-washington-d-c/E72669A71943D0C51D8EE72669A71943D0C51D8E

Your Personal Greenhouse Gas Emissions

Follow this link to the EPA's personal greenhouse gas emissions calculator.

Green Dry Cleaning

The "Green Chemistry" section of this chapter that focused on -friendly dry cleaning peaked my interest as another way to cut back on the use of traditional organic solvents. The conventional solvent used in dry cleaning is perchloroetheylene (PERC) which contaminates ground water and is suspected to be carcinogenic in humans.

Joseph DeSimone developed a polymeric surfactants for carbon dioxide and founded a chain of dry cleaners that uses liquid carbon dioxide instead of PERC to clean clothes. This method not only cuts down the use of harmful organic solvents but also captures CO2 for practical purposes when it would otherwise be released into the atmosphere and cause global warming. The following website has a directory of green dry cleaners in the area :

http://www.ecovian.com/s/sandiego/green-dry-cleaners-wet-cleaning

So next time you need to get something dry cleaned, try it out!

Do you need your catalytic converter?

While reading about ground-level air pollution, I was struck by the the section on VOC and NOx reduction. The concept of reaction dependence on particular compounds based on a given set of conditions is fairly standard, but the implications of the affects of NOx reduction in certain areas were quite interesting. In NOx-limiting regions, high concentrations of VOCs produce an abundance of HOO and ROO free radicals, which react with nitric oxide to produce the hydroxyl radical and nitrogen dioxide. Nitrogen dioxide then proceeds to undergo photolysis to produce atomic oxygen, which combines with molecular oxygen to form ozone. So, in this case, we see an increase in ground-level ozone due to the presence of nitric oxide molecules. Conversely, in VOC-limiting regions, the existence of NOx, specifically nitrogen dioxide, reacts with the hydroxyl radical to form nitric acid and effectively inhibits the production of ozone by decreasing the amount of OH radical available to react with VOCs. In this case, NOx actually help in the prevention of ozone formation.

VOC-limiting areas tend to be urban parts of the globe, which brings about somewhat of an environmental paradox: If reducing NOx levels in VOC-limiting regions, which tend to be urban areas, will increase the amount of ground-level ozone produced, how beneficial are catalytic converters? Do they not decrease the level of NOx produced from fuel emissions, which would imply that more of the hydroxyl radical in urban areas would be free to produce ozone by reacting with VOCs? It seems as though there is a trade off between decreasing the amount of NOx air pollution and preventing ground-level ozone production. Would it not be more beneficial to reduce VOCs in urban areas since those compounds are the ones the hydroxyl radical will react with if NOx levels are low? I found very similar postulates in a paper published in 2004 on the "weekend effect," which involves the effects of the lower levels of NOx due to decreased truck travel during weekends on ground-level ozone production.

http://www.aei.org/outlook/19746

It's an interesting topic of debate. Is our current environmental policy of NOx reduction in urban areas the best policy based on the chemistry we know occurs in VOC-limiting regions?

In performing the ozone lab I became interested in the processes by which ozone is created by electrical equipment such as a high powered blender or copy machine. Dr. Dehaan explained that the electric arc within such machines supplies the energy needed for ozone to be produced from ambient O2 molecules. 3-O2 --Electric Energy--> 2-O3. Electronic motors that are driven by an electric arc are common in many household devices such as brush vacuums and kitchen appliances. Other less common items that produce significant electric arcs are tasers and photocopiers. Though these devices are known to produce ozone, preliminary tests of a high-powered blender were lower than those recorded outside (note: the time of the blender test was shorter by 25 minutes). Some lamps which utilize a gas in a pressurized tube contain open electrical arcs that can, over time, produce dangerous amounts of ozone. In researching this subject, I came upon a patent for a device that attaches to such lamps that converts toxic ozone into oxygen. The fact that such a device exists is a testament to the ability of such electrical arcs to produce ozone in large amounts.

http://www.patentstorm.us/patents/3949258/description.html

In nature, electrical arcs millions of times more powerful than those found in electric appliances can be found in the form of lightning. Lake Maracaibo in Venezuela is a location which has higher incidences of lightning than almost any other location on earth. These frequent lightning storms occurring many times per day produce huge amounts of ozone from oxygen in the air and according to some, this phenomenon represents the largest single contribution to ozone in the troposphere.

http://en.wikipedia.org/wiki/Catatumbo_lightning

Green Chemistry: Harpin Technology

Harpin is a naturally occuring bacterial protein that is being used to replace the pesticide (and more specifically, soil fumigant) , methyl bromide. This protein can be isolated from proteins. When applied to plants it initiates plant defenses against bacterial, viral, and other types of diseases. The harpin initiates the plants "hypersensitive response" and physically barricades infection from spreading. Another benefit to harpin use may be that pests can not form an immunity to it because it indirectly affects them. Additionally, harpin has no effect on the plant's DNA, it is only able to activate the plant's innate defenses. The benefits of harpin technology are plentiful: it's production only produces biodegradable waste, harpin itself has low toxicity, and it can also act as a plant growth stimulant!