ATS 350 LATEST UPLOAD EXAM 2025

ATS 350 LATEST UPLOAD EXAM 2025 What are the major forces that generate atmospheric circulations? - Correct Ans- 1. pressure gradient force 2. coriolis force 3. friction Why does the pressure gradient force exist? - Correct Ans-To restore equilibrium, always directed from high to low pressure Why does the coriolis force exist? - Correct Ans-Because of earth's rotation. It is always perpindicular to the wind, it increases as the wind speed increases, it changes the wind direction and not speed, it is largest at the poles, it is zero at the equator, and it is to the right in the northern hemisphere Why does friction exist? - Correct Ans-It exists close to the surface because the surface isn't smooth. It is the opposite direction of the wind and slows the wind down. How would you draw the wind forces for a low pressure system in the northern hemisphere? - Correct Ans-The wind direction is counter clockwise. The pressure gradient force is toward the middle. The coriolis force is to the outside. The friction is opposite direction of the wind if close to the surface. How would you draw the wind forces for a high pressure system in the northern hemisphere? - Correct Ans-The wind direction is clockwise. The pressure gradient force is toward the outside. The coriolis force is to the middle. The friction is opposite direction of the wind if close to the surface. How would you draw the wind forces for a plot of straight isobars in the northern hemisphere? - Correct Ans-The wind direction is curved. The pressure gradient force is toward the lowest pressure. The coriolis force is the opposite direction. The friction is opposite direction of the wind if close to the surface. How does the spacing of isobars or lines of constant height determine the wind speed? - Correct Ans-The closer the isobars, the faster the wind. If the isobars are closer there is a sharper gradient in pressure. So the PGF is stronger, increasing wind speed How does temperature determine the height of constant pressure surfaces aloft? - Correct Ans-Warm air aloft expands the atmosphere, making the 500 mb pressure surface higher. I.e. hotter air is less dense, so you have to go higher to achieve the same pressure. How does temperature determine the pressure on constant height surfaces? - Correct Ans-At higher temperatures, the pressure is lower because it is less dense. ATS 350 ATS 350 As the height of constant pressure surfaces rise and fall horizontally, how does this correspond to horizontal variations in pressure? - Correct Ans-Low height are troughs that correspond to low pressure. High height are called ridges and correspond to high pressure What devices measure wind speed and direction? - Correct Ans-anemometer and wind vanes What causes a sea breeze? - Correct Ans-A sea breeze is caused by the land warming up more than the ocean, leading to low pressure over the land and high pressure over the sea. When does a sea breeze typically occur? - Correct Ans-A sea breeze typically occurs during the afternoon. What causes a land breeze? - Correct Ans-A land breeze is caused by the land cooling more than the ocean, leading to high pressure over the land and low pressure over the sea. When does a land breeze typically occur? - Correct Ans-A land breeze typically occurs during the night. What weather conditions favor the formation of a land breeze? - Correct Ans-A land breeze particularly happens under clear skies with radiative cooling. How do pressure differences drive circulation? - Correct Ans-1. Initially no horizontal temperature gradients, so everything is constant pressure. 2. Heat the left side and cool the right 3. The left side expands and the right side contracts. 4. This generates higher pressure aloft than on the right. 5. A PGF aloft drives air from high to low (left to right) 6. Movement of the left column lowers the surface pressure on the left 7. Surface pressure is raised on the right side due to movement into this column 8. A PGF near the surface drives air from high to low (right to left) 9. This results in a large scale circulation cell with rising air in the warm column and sinking in the cold. What is a monsoon? - Correct Ans-A monsoon is a regional circulation system characterized by seasonal changes in wind speed or direction. How do ocean and land temperatures vary in a monsoon? - Correct Ans-Ocean temperatures don't vary much, but land temperatures do. What happens to pressure over land during the summer in a monsoon? - Correct Ans Warmer temperatures over the land during the summer create low pressure over land. ATS 350 ATS 350 What is the effect of onshore flow during summer in a monsoon? - Correct Ans-Onshore flow during summer leads to more precipitation over land. How does precipitation vary between summer and winter in a monsoon? - Correct Ans Precipitation is suppressed over land during winter. Understand local circulations associated with downslope/mountain wind storms, including the importance of mountain waves and rotors. - Correct Ans-Over the mountains, stable atmospheres have oscillating flow. This can lead to downslope flow and rotor eddy systems Understand mountain and valley breezes, why they form, and how they vary during the day. - Correct Ans-Air next to the surface of mountain slopes is heated/cooled more in the day/night. This difference in density leads to upslope flow during the day and down slope flow at night. Understand the importance of Earth's rotation for influencing atmospheric circulations at large and small scales. - Correct Ans-On small scales, the Earth's rotation isn't important and wind blows in the direction of the PGF. On very large scales, wind flow is heavily influenced by the coriolis force. This is why we have a 3 cell model Understand the one-cell model for the atmosphere's general circulation, the assumptions made in formulating it, and why it does not exist on the real Earth - Correct Ans-This assumes the earth is not rotating. Energy is transported from the equator to the poles as air rises in the equator and sinks in the poles. This doesn't exist because the earth rotates, and the coriolis force deflects air flow. What are the three cells of the atmospheric general circulation? - Correct Ans-The Hadley cell, the Ferrel cell, and the Polar cell. What is the primary reason for the existence of the three-cell structure in atmospheric circulation? - Correct Ans-Coriolis force. What type of motion occurs in the tropics within the atmospheric general circulation? - Correct Ans-Rising motion. What type of motion occurs in the subtropics within the atmospheric general circulation? - Correct Ans-Sinking motion. What atmospheric phenomenon is associated with midlatitude storms? - Correct Ans Ferrel cell. ITCZ and low tropical pressure - Correct Ans-The intertropical convergence zone is characterized by the rising motion of the hadley cell. Hence, there is low surface pressure. It is also where the trade winds are (blow east) ATS 350 ATS 350 Hadley Cell - Correct Ans-The hadley cell is driven by the N-S gradient in heating, so air rises near the equator and sinks near 30 degrees. It explains deserts, trade winds, and ITCZ. The coriolis force deflects flow in this cell, creating the subtropical Jet stream and the trade winds Ferrell Cell - Correct Ans-The middle atmospheric circulation cell in each hemisphere. Air in these cells rises at 60 degrees latitude and fall at 30 degrees latitude. It is driven by heat transports of eddies and explains surface westerlies. Trade winds - Correct Ans-prevailing winds that blow from east to west from 30 degrees latitude to the equator in both hemispheres; also called westward. Caused by the coriolis force of the hadley cell Midlatitude westerlies - Correct Ans-belt of west to east airflow in the midlatitudes (30° 60°). Caused by the coriolis force again due to coriolis force in ferrel cell Doldrums - Correct Ans-Weak winds found near the equator -- air blows straight up instead of blowing horizontally Polar front - Correct Ans-boundary at which cold polar air meets the warmer air of the middle latitudes Subtropical high pressure - Correct Ans-A broad, high pressure zone of hot, dry air found between 20 and 35 degrees latitude in both hemispheres due to sinking air of hadley and ferrel cells Why do jet streams exist, and more particularly, how do strong heating and temperature gradients lead to pressure gradients and jet streams? - Correct Ans-Coriolis force on hadley and ferrell cell circulation. How does conservation of angular momentum aid jet stream development? - Correct Ans-Coriolis force deflects winds Where do major jet streams occur - Correct Ans-There is a polar jet and a subtropical jet What is Ekman transport? - Correct Ans-Wind blows on the ocean creating a force (wind stress). There is a force balance between this stress and the coreolis force. The upper ocean (ekman layer) moves 90 degrees to the right of the wind direction in the northern hemisphere In what direction does Ekman transport occur for an applied wind stress to the ocean in the a) Northern Hemisphere?, b) Southern Hemisphere? - Correct Ans-a) right to the wind direction b) left to the wind direction ATS 350 What is upwelling? - Correct Ans-The rising of cold water from deeper layers to replace warmer surface water. Basically, when the water is deflected due to ekman flow, cold deep ocean water can rise to replace it Why do winds on the west coasts of continents force upwelling in the ocean during summertime? - Correct Ans-There is a HPS on the west coast. This means the wind direction is to the south (NH), so Ekman flow is to the east, away from the continent If the Earth were either all ocean or all land, would features such as the Aleutian Low, Bermuda High, and Siberian High exist? Why or why not? - Correct Ans-No. Without land, circulation would be relatively the same around each latitude. This leads to bigger seasonal variations as well. What are El Nino and La Nina? - Correct Ans-El Nino is associated with warm water across the equitorial pacific, shifting convection to the east pacific. La Nina is associated with cold water, shifting convection to the west Why do the subtropical ocean gyres exist? - Correct Ans-PGF and coriolis force