Study Guide Exam1

Exam1 Study Guide 1) Be familiar with the Moore, Oklahoma Tornadoes case study as it pertains to the 5FC. 1. Computer modeling system, NWS had been forecasting the risks of thunderstorms and potential tornados days before the 2013 tornado. 2. There is a 1% daily chance of a tornado hitting your home, but this percentage had a great risk to life and property. 3. The linkages between this hazard were flooding, thunderstorms, high winds, and hail. 4. The population in Moore grew by 30% which increases the risk of tornado hazards to life, Moore also didn’t have shelters, underground shelters, etc. 5. The consequences of hazards can be minimized by installing overhead doors in buildings and schools, providing a community shelter, etc. 2) Understand the difference between heat and temperature. Understand the role of latent heat in atmospheric processes and be able to explain the different mechanisms of heat transfer (convection, advection, radiation) as it is applied to atmospheric circulation. Heat is the total energy of molecules of a substance (how fast particles are moving). Temperature is a measure of the average molecular motion. Latent heat is energy that is absorbed or released when matter changes physical states. Convection is a heat energy transfer mechanism where energy is transferred because of vertical mass movement driven by density differences. Radiation is an energy transfer mechanism where energy emitted from a heat energy source is transferred elsewhere. The energy is transferred in the form of electromagnetic waves. 3) Be able to explain what is meant by “Earth’s Energy Balance,” and how this energy is related to Earth’s climate and weather processes. The earth’s energy balance is achieved as the energy received from the Sun balances the energy lost by the Earth back into space. In this way, the Earth maintains a stable average temperature and therefore a stable climate. 4) Know what differentiates the troposphere from the stratosphere and be able to explain what effect this difference has on atmospheric circulation and weather. The troposphere extends about 8 to 16 km above the surface of the earth except for some jet travel, we spend most of our lives within the troposphere. The troposphere has a rapid upwards decrease in temperature that results from decreasing air pressure with increasing altitude. The troposphere is abundant in condensed water vapor in the form of clouds, most of the clouds that affect us are found here. The stratosphere has a temperature rise because of the ozone molecules that absorb solar radiation, it acts as a lid, keeping air from rising and condensing past the tropopause. 5) Understand the Coriolis effect and be able to explain and draw the effect that Coriolis has on horizontally moving air masses north and south of the equator. Coriolis is the result of Earth's rotation on weather patterns and ocean currents. In the northern hemisphere air masses are deflected to the right, whereas in the southern hemisphere, they are deflected to the left. The Coriolis effect makes storms swirl clockwise in the Southern hemisphere and counterclockwise in the Northern Hemisphere. 6) Be able to draw the generalized vertical and horizontal circulation patterns of Earth’s Atmosphere concerning latitude, and regions of high and low pressure. Hot air rises at the equator and descends at 30 N and 30S latitude, repeating moving towards poles every 30 degrees of latitude, arrows must agree at each latitude, air moves from high to low pressure. Latitudes of rising air have low pressure and latitudes of descending are high pressure. The horizontal movement of air is deflected to the right in the NH and to the left in the SH. 7) Understand the relations among atmospheric characteristics; heat, temperature, pressure, density, pressure, and effective humidity (the ability of air to hold water in a gaseous state). This means being able to explain how all other characteristics may change as a result of changing just one of the other characteristics. Density is indirectly proportional to temperature but directly proportional to pressure. As pressure increases, with temperature constant, density increases. When temperature increases, with pressure constant, density decreases. The more humidity in the air also lowers the density. Adding heat increases temperature, which expands air, and decreases the density, air rises, heat is lost, which produces clouds and precipitation, temperature decreases, air contacts, density increases, air sinks, and air compresses and warms. 8) Understand how relationships in the question above affect local climate regimes around the globe.

9) Know what cold and warm fronts are, how they are produced, and be able to explain how and why the weather is different at these font types. Cold fronts are when a cold air mass is moving into a mass of warm air and forces warm air upward, this rising warm air creates clouds and heavy precipitation. A warm front is when an advancing warm front forces warm air to rise over cooler air. Clouds and precipitation may develop, and light precipitation is dumped over a long distance. 10) Be able to explain what the needed characteristics of the atmosphere are to generate a supercell thunderstorm and be able to explain the role each of these characteristics plays in the development and sustainability of the storm. Warm humid air must be present in the lower atmosphere to feed clouds and precipitation and provide energy to the storm, a steep vertical temperature gradient through the atmosphere, a cold front must force warm humid air rapidly into colder levels of the atmosphere, wind shear is needed to tilt the storm separating up and down drafts. If the moisture supply and updraft continue, the relative humidity increases in the air surrounding the cloud and it grows in size instead of evaporating. A Supercell storm is defined by the presence of an upward spiraling column of air – vertical axis rotation created by vertical wind shear- known as a mesocyclone. Updrafts produced by rising warm air lift the horizontally rolling air toward the vertical. A vertical rotating mesocyclone develops. 11) Know what the significance of a wall cloud is and where they develop in the storm system and know how the formation of the wall cloud and tornado are related to processes in the supercell thunderstorm. A wall cloud forms from a major updraft often in the rear or southwestern part of the storm, that lowers a portion of the cumulonimbus cloud. This cloud may begin to rotate, and a short funnel cloud or tornado may descend. Wall clouds commonly form in a supercell thunderstorm. 12) Know the difference and processes behind the formation of snow, sleet, freezing rain, hail, and rain. Snow forms when precipitation falls as snowflakes and remains as snow since it doesn’t pass through the warm air. Sleet forms when falling snowflakes melt if they encounter warm air aloft, and the resulting rain refreezes to form ice pellets if there is sufficient time and cold air before they reach the ground (freezing rain that goes from air above freezing to air below freezing). Freezing rain forms if there is only a thin layer of cold air at the surface, raindrops become supercooled and then freeze immediately upon contact with a cold surface such as a tree limb, house, or power line. Rain forms when snowflakes melt, and rain will fall if a thick warm air layer is at the surface. Hail is formed when raindrops are carried upward by thunderstorm updrafts into extremely cold areas of the atmosphere and freeze. 13) Know what it means for a storm to be “stalled” why this might occur and what the implications are if you are unfortunate enough to be caught under a stalled storm. The storm slowed and remained to linger, this occurs because the environmental wind field becomes weak, it is away from its influences. You can be found under a lot of inches and feet of rain if it is a hurricane. 14) Be familiar with the Hurricane Sandy and Hurricane Katrina Case Studies concerning the 5 FC. 1. Computer models are used to predict the track of the hurricane such as the NHC global model and the ECMWF, the intense high-pressure ridge over Greenland, etc. 2. Effects of rising sea level can help people assess the risk, building codes of homes, knowing flood zones. 3. The linkages are storm surges, flooding, strong winds, coastal erosions, rain in Georgia, the Carolinas, and Virginia, tornado in Bermuda, and heavy snow. 4. Infrastructure in high-risk flood areas, the development of Staten Island since it is at a 120-degree angle that is prone to massive storm surge, subway system. 5. Building codes for building requirements, those that were up to date withheld the storm better, FEMAS flood zone had many people evacuated from high- risk flood areas. 15) Know the fundamental variables required for tropical cyclone development and explain their role in developing and sustaining the storm. Tropical cyclones develop between 5/8- and 20-degrees latitude, Coriolis, warm and humid air is needed. It usually starts as a tropical disturbance, which is a large area of unsettled weather that is typically 200-600 km in diameter and has mass thunderstorms of over 24 hours. Many of the cyclones form off the west coast of Africa because of the heat, which sets up the low pressure with sustained winds between 39-73 mph as easterly waves that start over the west coast of Africa and migrate westward with the trade winds toward the Caribbean and US eastern seaboard and gulf coasts. 16) Explain the differences between Hurricanes, Tropical Cyclones, Extratropical cyclones, and Typhoons, and be able to identify where they form and why. Be able to draw a hypothetical path that they might follow as

of the infrared radiation passes through the atmosphere but most are absorbed and re-emitted in all directions by greenhouse gas molecules and clouds. The effect of this is to warm the earth’s surface and the lower atmosphere. 25) Know what is meant by “abrupt climate change”. Know what the Ocean Conveyer Belt is and how it moderates climate, and what effect its collapse could have on global/local climate. Abrupt climate change is a large-scale change in the global climate that takes place over a few decades or less. The ocean conveyer belt is a large-scale circulation pattern in the Atlantic, Indian, and Southwestern Pacific Oceans that is driven by differences in water temperature and density; also referred to as a thermohaline current. Northward-flowing warm water in this current maintain the moderate climate of northern Europe; if this current were to slow or stop, ice-age conditions might return to portions of the Northern Hemisphere. 26) Be prepared to discuss several of the effects of increased carbon dioxide and global warming/climate change on the planet (Positive and negative feedback). Positive feedback is A produces more of B which in turn produces more of A. Negative feedback occurs when some function of a system, process, or mechanism is fed back in a manner that tends to reduce the effects, it reduces the effect of change. An example of positive feedback can be seen through ocean warming, as CO2 increases, it increases the warming potential of the planet, which results in the ocean’s warming and warmer oceans decrease the ocean's uptake of CO2, and as a result, it stays in the atmosphere. An example of negative feedback from increased carbon dioxide is that trees and plants soak up the CO2 for growth.