Lines of longitude are (approximately) used as a basis for world time.
The world rotates in a counterclockwise direction (west to east) about its axis
once a day. Thus, the earth rotates 360 degrees of longitude every 24 hours.
1) a) How many degrees does the earth rotate every hour? ___________
b) A place 45 degrees west of Carrollton, GA will have sunset (sooner or later)? This time will be the time for those people living on the west coast (Pacific time zone).
c) If it is noon on the prime meridian, What time is it in Alexandria, Egypt? (32°N, 30°E)
Now, let's examine time zones here in the US -- basically, there are four:
EST Eastern Standard Time
CST Central Standard Time
MST Mountain Standard Time
PST Pacific Standard Time
As mentioned, there are approximately 15° of Longitude between each, however, due to political/demographic boundaries, 15° is only approximate.
2) Give the time zone code and the standard meridian (in degrees of longitude) for the following places:
Time zone Std. Meridian
Cleveland, OH ________ ________
Las Vegas, NV ________ ________
El Paso, TX ________ ________
Chicago, IL ________ ________
Denver, CO ________ ________
Montreal, Quebec ________ ________
Vancouver, BC ________ ________
Atlanta, GA ________ ________
Moscow, ID ________ ________
3) Of the four time zones shown on the map, which one spans the greatest extent
in longitude
within the lower 48 states? _______________ The estimated maximum width of this zone
in degrees of longitude is ____________.
4) Clock differences between cities: When it is 11 AM in Los Angeles, the time
in Atlanta is
_________. When it is midnight in Pittsburgh, the time in San Francisco is _________.
When it is 3 PM in New York City, it is _________ in Honolulu, Hawaii.
Standard Time throughout the world. Refer to the world map on the next page. Designate the zones in terms of hours fast (minus sign) and hours slow (plus sign). Greenwich time (zero hours) is based on the Greenwich (or Prime) Meridian (Zero Longitude).
5) Give the time zone for each of the following nations:
Japan _________
Iceland _________
Iran _________
Chile _________
India _________
New Zealand _________
Greenland _________
note: this image scanned from Strahler and Strahler's text: Introducing Physical Geography, 2000. Page 22. Your text will have a very similar image.
worth 2 points, due monday, 19 July, 2004.