Effects of Atmospheric Instability on the Anthrosphere :: Geology

EFFECTS OF ATMOSPHERIC INSTABILITY ON THE ANTHROSPHERE INTRODUCTION The atmosphere rises to 500 km above Earth's surface. The atmosphere is divided into four parts based on temperature change in relation to change in altitude. The four parts are the: Troposphere, Stratosphere, Mesosphere, and Thermosphere. This paper will be discussing instability in the Troposphere, the lowest level, since it is where the Earth's weather takes place. Tropospheric instability often times yields severe weather, such as tornadoes. A Tornado is a violently rotating column of air in contact with the ground and pendent from a cumulonimbus cloud. A tornado's fierce winds have the ability to severely impact the lives of humans by: turning innocent stationary objects into flying missiles, collapsing buildings, and even throwing people hundreds of yards. One researcher summarized tornadoes well when he said "Tornadoes are one of the World's strongest forces, and they will not stop at anything that will get in their way!"(Elias Demakes). FORMATION OF SEVERE WEATHER HOW: Atmospheric instability is the result of air rising in a cloud that is warmer than its surroundings. The heat released by the condensation within the cloud allows the rising air to maintain its relative warmth in comparison to its surroundings. This is characteristic of a supercell, the strongest type of thunderstorm (Supercell). Supercells occur when the warm updraft moves through an overlying stable layer and continues upward into a zone of cool dry air. This process produces fierce vortex motions, a pre-requisite for tornadoes. WHERE: Tornadoes can occur anywhere as long as the conditions are favorable. However, the United States is host to more tornadoes than any other country. And within the United States, geographically, the western plains has the highest frequency of tornado occurences. The western plains has so many that it has become known as "Tornado Valley". One reason that this area receives so much tornadic activity is because here, the warm, moist air from the Gulf of Mexico converges with the cool dry air from the north. This creates the unstable atmosphere necessary for the formation of a tornado. WHEN: Tornadoes can occur on any day of the year at any hour. However, tornadoes occur most frequently in the spring.