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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 ...
Proposed by George Hadley in 1735, it is the tropical convection system that describes the atmospheric thermal circulation of air from the equator (0 degrees latitude) poleward to 30 degrees both north and south of the equator. When saturated air at the intertropical convergence zone (ITCZ), located approximately at the equator, is heated, convergence and convection causes it to rise into the upper atmosphere, creating an area of low pressure at the earth's surface. As the pocket of saturated air at the ITCZ rises, it cools, releasing large amounts of precipitation. Rather than remaining in the tropics, the air then flows horizontally towards the higher latitudes. At approximately 30 degrees both north and south of the equator, the pocket of air in the upper atmosphere has sufficiently mixed and cooled enough to return to the surface. To complete the circle, the area of low pressure at the equator pulls air in from the higher latitudes.
Industry:Chemistry; Weather
Rate at which unsaturated air cools as it travels vertically, provided that all temperature change is adiabatic (without heat exchange), and no condensation occurs. In dry air it can be approximated as 9. 8 degrees Celsius per km of rise. It can be used as a basis of comparison for actual temperature profiles of air and can help predict smoke stack gas dispersion characteristics. Contrast with saturated adiabatic lapse rate which is something less than 9. 8 degrees/km of rise because of the release of heat at the air packet cools and water vapor condenses.
Industry:Chemistry; Weather
Recent data suggest that due to the release into the atmosphere of CFCs by human activities, the ozone hole can as large as North America during a given astral spring. The CFCs are broken apart by UV light--to form free radicals of chlorine--after they have diffused into the upper stratosphere from the troposphere. This long term movement from the troposphere to the stratosphere is possible for these chlorine containing chemicals because of there long atmospheric lifetimes; however, this type of movement is not important for more reactive species such as tropospheric ozone because of their reactivity and therefore short atmospheric lifetime. In the Antarctic stratosphere, the reaction that converts reservoir species of chlorine into an active form--which destroys ozone--takes place on the surface of particles in polar stratospheric clouds as the temperature drops below about 200K. This is possible because of the unique isolation of the south polar vortex during the austral winter. The surfaces of these (nitric acid/water) clouds act as catalysts for reactions that release molecular chlorine which quickly photolyzes to chlorine's (radical) active state. It is this radical which destroys ozone.
Industry:Chemistry; Weather
Reduction of radiation reflecting from earth per units of increase of a chemical component that causes this change in the atmosphere. The result is often used to compare the relative effect of greenhouse gases which can alter climate on earth. This means that components that are present in the atmosphere at low concentrations (e.g. methane at 1. 7 ppmv) but with high radiative forcing have a greater effect on global warming than higher concentration components with a lower radiative forcing.
Industry:Chemistry; Weather
Refers to reflection power or the portion of solar radiation that reaches a body (earth) surface and is immediately reflected back into the atmosphere. The uncertainty in the reflective power of clouds unfortunately increases the complexity of determining clouds' effects on modeling global warming.
Industry:Chemistry; Weather
Refers to something originating from humans and the impact of human activities on nature.
Industry:Chemistry; Weather
Related to Antarctic ozone depletion, this denotes the season of spring in the southern hemisphere when the greatest amount of ozone is lost, generally beginning in September. Astral relates to the hemisphere that the observer is currently in and the season that relates to the observer, while austral refers to the south.
Industry:Chemistry; Weather
Relatively unusual wavy, thin, bluish-white clouds that form at altitudes of about 80 to 90 km.
Industry:Chemistry; Weather
Sandstorms that occur in the deserts. As a thunderstorm is ending there is a decrease in water droplet fall. The desert's air is extremely dry and able to evaporate the water as winds rush towards the desert's surface. As winds continue to hit the surface they form a circular wind pattern containing sand which increases in force and speed to form the sandstorm. In the summer of 2011 a haboob hit Phoenix Arizona USA that was 100 miles wide and a mile high. Sandstorms blowing west off Africa take phosphate out towards the Atlantic Ocean and sometimes even as far as South America. This phosphate may be an important source of phosphorus in phosphorus-limited biomes.
Industry:Chemistry; Weather
Satellites are electronic devices placed into orbit to monitor and examine regions which we may not be able observe from earth. These are used routinely to monitor atmospheric ozone, ultraviolet radiation, and many other constituents. Satellite altimetry and radar interferometry are used to measure magnetic field intensity and track Antarctic ice flow. Geosynchronous satellites--whose orbit is 24 hours--are used for communication. Arthur C. Clarke proposed the concept of geosynchronous satellites in 1945.
Industry:Chemistry; Weather
