NAME: ___________________________________________________________ Atmospheric Sciences 101, Summer 2003 Homework #5 Accepted through end of lecture Thursday, 7 August 2003 ***No assignments may be turned in after that time*** 1. Jet streams a. During which season is the polar jet stream weakest? Explain your answer. b. Why do the jet streams (not to mention the Hadley cells and the <a href="/keyword/intertropical-convergence-zone/" ><a href="/keyword/intertropical-convergence/" >intertropical convergence</a> zone</a> ) move north and south during the course of each year? 2. Ocean circulations a. Explain why the surface waters just off the coast of California are so cold. (Hint: Begin the description with the large-scale surface pressure pattern and the resulting surface winds.) b. What is the cause of most of the surface currents of the ocean? 3. <a href="/keyword/intertropical-convergence-zone/" ><a href="/keyword/intertropical-convergence/" >intertropical convergence</a> zone</a> (ITCZ) a. What at the surface near the Equator causes the ITCZ? b. Why is heavy precipitation typical at the ITCZ? 4. Hot Seattle summer weather Seattle almost never experiences extended heat waves (i.e., several consecutive days with temperatures above 90 F). What specifically often happens to break a heat wave when it does occur here during the summer? (Hint: In your answer describe the pressure patterns and local circulation that develop in association with very hot temperatures around Puget Sound.) 5. El Ni o Southern Oscillation (ENSO) Use the links at http://www.atmos.washington.edu/2003Q3/101/homework/hw5enso.html (linked on the class assignments webpage) and also listed below to help answer these questions. a. Fill in the table below describing how El Ni o and La Ni a events typically affect winter weather in the Pacific Northwest. (Hint: see http://www.wrcc.dri.edu/enso/ensofaq.html) El Ni o Temperature Precipitation Snowpack La Ni a b. Which years during 1980-2003 had the 3 strongest El Ni o events of that period? Similarly, which 3 years out of the period 1980-2003 had the strongest La Ni a events? (Hint: see http://www.srh.noaa.gov/tbw/information/nino.htm) c. View the tables of average winter temperature and precipitation for the state of Washington over the winters of 1980-2003 at: ht...