ATM OCN (Meteorology) 100
WEB ACTIVITY for
Homework 2
Summer 1999
Date Due: Thursday, ??? June 1999
BACKGROUND
Have you ever needed to know when the sun would set in your town? Knowledge
of the time of sunset or sunrise may be
needed for planning purposes, for legal matters or for scientific investigations.
The local times of sunrise and sunset for each day
of the year are provided by many almanacs and appear in the media,
such as in the newspapers or on television. These times
are defined as the instant when the top of the solar disk is just at
the local level horizon. They can be calculated for any place
using well known angular relationships that take into account the latitude
of the observer (how far one is from the equator in
angular measure) and the day of the year (which essentially describes
the seasonal course of the tilt of the earth's spin axis with
respect to the sun). The U.S. Naval Observatory has prepared sunrise-sunset
tables for over 200 locations throughout the
country. Inspecting these tabulations reveals several interesting features
described below. An on-line, interactive service is
available that allows you to determine the times of sunrise or sunset
for individual
days or the entire
year at most cities in the
United States.
ASSIGNMENT
For Madison, Wisconsin -- The sun will set today ______________ (please
date) at ___________________ (time).
(Note that the table is in standard time, so add one hour for daylight
time)
The earliest sunset of the year in Madison is about what date
_____________________?
The latest sunrise of the year in Madison is about what date
_____________________ ?
The latest sunset of the year in Madison is about what date
_____________________ ?
The earliest sunrise of the year in Madison is about what date
_____________________ ?
The times of sunrise and sunset on the spring equinox (21 March) is
_______________ and ________________.
Last revision: 16 June 1999
Produced by Edward J. Hopkins, Ph.D.
Department of Atmospheric and Oceanic Sciences
University of Wisconsin-Madison, Madison, WI 53706
hopkins@meteor.wisc.edu
URL Address: aos100/homework/99hmk02k.htm