Relative humidity can be changed by...Changing the water vapor content.Add water, increase relative humidity.subtract water, decrease relative humidity.Changing the temperature.Increase temperature, decrease relative humidity.Decrease temperature, increase relative humidity.Convergence lifting - when flowing air masses of equal density converge and are forced upward.Convective (Density) lifting - When warm, low-density air rises convectively and displaces cooler, denser air.Orographic lifting - When flowing air is forced upward over a mountain range.Frontal lifting - when two flowing air masses of different density meet.The Coriolis force is due to the rotation of the earth on its axis. The Coriolis force deflects all free moving objects to the right of their path in the Northern HemisphereOccur mostly in late spring - early summer when conditions are best for tornado formation; but can occur anytime. As the season progresses, tornado formation migrates northward.The severity of a tornado is categorized based on wind speed estimated from the damage that they cause on the Fujita Scale.They originate over warm tropical or subtropical water off west Africa where warm air rises in a low atmospheric pressure cell that builds as heat and moisture are added from the ocean. They track towards North America because they are pushed by the trade winds and curve northward as they approach the east coast of North America due to the Coriolis force.Just outside the eye (in the “eyewall”)Cold, dry air is descending from above.Winds in the northeastern quadrant of the storm are directed toward the shoreline and inflict the greatest damage. Southeastern-quadrant winds are directed offshore and inflict the least damage. Local circumstances that increase the height of storm surge include a bay which will funnel the water and raises the surge and a moving into shallow water which causes the water to pile up and raise sea level locally.The high winds cause the greatest amount of dollar damage. Storm surge is responsible for 90% of the deaths in a hurricane.Strong vertical wind shear tears the hurricane apart.Moving over cooler water can lead to weakening.Moving over land shuts off the moisture source and reduces surface circulation due to friction.Too many people delay so traffic jams are common.There is generally only one two-lane bridge from a barrier island to the mainland.Downed trees and power lines may block roads.The surge may submerge or wash out the road.Name: _______________________Learning Unit 6: Extreme Weather Review QuestionsThis assignment is designed to assess your understanding of Unit 6 and includes some of the Questions forReview at the end of Chapters 10, 15 and 14 from your text plus a few additional questions. Each question can be answered in one to two sentences. Please limit yourself to a maximum of three sentences. Access the assignment, complete it with ANSWERS IN A DIFFERENT COLOR FONT as a separate file, and send it back for evaluation and grading through the assignment tab by or before the due date. 1. What causes the Earth’s seasons, such as winter and summer?Seasons result from the tilt of the Earth’s axis with respect to its annual orbit around the sun. For example, summer in the northern hemisphere results from the tilt of the northern hemisphere towards the; winter in the northern hemisphere results from the tilt of the northern hemisphere away from the sun in winter.2. How do greenhouse gases warm the Earth’s atmosphere?They permit radiant energy from the sun to heat the Earth’s surface but prevent that heat from rising back into space.3. An area of low atmospheric pressure is characterized by what kind of weather? clouds, rain, storms4. What is the equation for calculating relative humidity and how do changes in water vapor content and temperature effect relative humidity?The ratio of the amount of water vapor in the air at a specific temperature to the maximum amount that the air could hold at saturation at that temperature, expressedas a percentage. Therefore the equation would be:Amount of water vapor in the air/the amount of water vapor the air can hold at saturation X100 = %RHRelative humidity can be changed by...• Changing the water vapor content.– Add water, increase relative humidity.– subtract water, decrease relative humidity.• Changing the temperature.– Increase temperature, decrease relative humidity.– Decrease temperature, increase relative humidity.5. What processes force air aloft?• Convergence lifting - when flowing air masses of equal density converge and are forced upward.• Convective (Density) lifting - When warm, low-density air rises convectively and displaces cooler, denser air.• Orographic lifting - When flowing air is forced upward over a mountain range.• Frontal lifting - when two flowing air masses of different density meet.6. What is the main distinction between a cold front and a warm front? Why are storms found at both warm fronts and cold fronts?In a warm front the warm air mass moves in and rises over the cold air. In a cold front the cold air mass moves in under, and lifts, a warm air mass.In both cases, the warm, more-humid air rises rapidly over cold air, cooling, condensing, and raining.7. What causes adiabatic lapse rate and what effect does the adiabatic lapse rate have on a rising parcel of air?The adiabatic lapse rate is the rate of temperature drop as a parcel of air rises to higher elevations, or the rate of temperature rise as a parcel of air drops to lower elevations. As the parcel of air rises the parcel expands under the lower pressure (pressure decreases with altitude). As a result the same number of air molecules is spread overa larger volume so the heat from those molecules is spread through a larger volume decreasing its overall temperature.8. Why do clouds have a fairly well defined base at a particular altitude?Air adiabatically cools as it rises. Eventually it reaches an altitude where the air cools enough that it becomes saturated with water (relative humidity inside the parcel reaches 100%). At even higher altitudes, any excess water vapor condenses to form water droplets creating clouds.9. What causes the Coriolis force and what effect does it have on free moving objects, including wind, in the northern hemisphere?The Coriolis force is due to the rotation of the earth on its axis. The Coriolis force deflects all free moving objects to the right of their path in the
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