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Founded in 1879 and named after Texas' greatest hero General Sam Houston, Sam Houston State University is public shcool within the Texas state university system and located in Huntsville, Texas.
It's a multicultural institution that offers 79 bachelorette degree programs, 54 masters and five ...
The Gulf Stream is a powerful current in the Atlantic Ocean. Its movement is related to density redistribution, differences in temperature, the Earth's rotation, and wind currents. Beginning in the Gulf of Mexico, it flows along the east coast of North America and across the Atlantic to Europe. The Gulf Stream carries warm water from the tropics and warms the climate of the land near where it passes. The relatively temperate weather in Great Britain is, to a large degree, controlled by the Gulf Stream redistributing energy from equatorial solar radiation to the North Atlantic.
Industry:Chemistry; Weather
The height in the atmosphere where pollution gets mixed and dispersed through the atmosphere. Factors controlling this phenomenon include solar radiation, wind speed, and local surface roughness. The mixing height is located at the top of a boundary layer and at the base of a temperature inversion.
Industry:Chemistry; Weather
The increase of the input into a system, which produces a negative or a positive output in a system of interlocking components; the return of a part or the effects of the output to the input. A proposed positive feedback cycle involves the outgassing of carbon dioxide from the planet's oceans: Since CO<sub>2</sub> solubility in water decreases with temperature and since CO<sub>2</sub> is a greenhouse gas, a positive (and possibly runaway) feedback cycle might involve the following: increased greenhouse warming of the atmosphere by IR absorbing CO<sub>2</sub> in the gas phase--and the subsequent heating of the oceans--could increase the amount of carbon dioxide released into the atmosphere from the oceans. This might thereby increase greenhouse warming, which would, in turn, again heat the atmosphere and the ocean, etc. This is an amplification of the input: positive feedback: leads to more warming. Though the process is no doubt more complicated than this, a runaway greenhouse effect is usually given as the reason for Venus' high surface temperatures so a planet-wide process of this type is not unknown.
Conversely, a negative feedback cycle might consist of the increase in release of dimethyl sulfide (DMS) by ocean surface microorganisms whose population is increased by ocean warming. DMS oxidation in the troposphere leads to sulfate aerosol formation which act as cloud condensation nuclei in the marine troposphere. Increased CCN would increase cloud albedo which increases reflect incoming solar radiation, thereby cooling the oceans. This is an dampening of the input: negative feedback: leads to termination of the original warming.
Industry:Chemistry; Weather
The is the ratio of a particular ozone depleting compound environmental effect compared to the depleting ability of a standard compound, CFC-11, which is arbitrarily defined as 1. 0. An example would be the ODP of of halon-1301 which is about 13. ,
Industry:Chemistry; Weather
The lack of oxygen such as the inadequate oxygenation of the blood (anoxia). In aquatic environmental chemistry it refers to water that has become oxygen poor due to the bacterial decay of organic matter.
Industry:Chemistry; Weather
The layer between the convective mixed layer and the free troposphere that is caused by a temperature inversion. This inversion inhibits the rising of heat and gases, trapping pollutants closer to the ground.
Industry:Chemistry; Weather
The layer of gas that forms above the surface layer as the gases of the convective mixed layer become more dense and lose their buoyancy. The formation of this nocturnal boundary layer is what caused the temperature inversion of the surface layer during the night hours.
Industry:Chemistry; Weather
The length of time a chemical species can survive without reacting, photolyzing, dissociating, or otherwise changing into another chemical species. Highly reactive chemicals have short lifetimes. For instance, if the reaction rate of a target species with an attacking species is very fast then the lifetime of the target species will be short. For example, the reaction of smalls radicals like hydroxyl radical in the troposphere is very fast with many common tropospheric species, and therefore the tropospheric lifetime of hydroxyl radical is measured in seconds.
Industry:Chemistry; Weather
The lifting of air resulting when cool air acts as a barrier over which warmer, lighter air will rise.
Industry:Chemistry; Weather
The light of the electromagnetic spectrum that we perceive with our naked eye. The wavelengths of light that we can see are between roughly 380 nanometers to 700 nanometers. Blue (shortest visible wavelength) light is preferably scattered by gases and particles in our atmosphere (see Rayleigh scattering) and this creates the blue sky that we perceive when looking away from the sun during daylight. When the sun is at its peak at noon, we see white light, since the light travels through the least amount of atmosphere, undergoing the least atmospheric scattering and therefore includes most of the visible wavelengths and therefore this mixture of light appears white. As the sun moves across the sky and the solar incident angle increases, the sunlight has to travel through more and more of the atmosphere--before it strikes our eyes at the surface of the earth--which causes increased scattering, again of blue light more than longer wavelengths. Mid-day, the sun will appear to be yellow and at sunset sunlight has to travel through the longest path of atmosphere scattering almost all blue, most green, and lots of yellow light, leaving mostly red sunlight to be seen by us. This means sunsets and sunrises often look reddish.
Industry:Chemistry; Weather
