1. Collection Location  (Where)

    The valid range for latitude is between -90 and 90 degrees, and the one
    for longitude is between -180 and 180 degrees. The program performs error 
    checking for these four entries.  

    If any entry is left blank, the program takes its limit value, -180 for 
    left longitude (west), 180 for right longitude (east), -90 for lower 
    latitude (south), and 90 for upper latitude (north). If all the four 
    entries are left blank, the program just ignores collection location 
    when querying the database.
  
2. Collection Date (When) 


    The program performs error checking for any invalid date. If 'from' date 
    is left blank, the program takes 01/01/1998 by default, and 09/30/2003 for 
    'to' date.

    If both the entries are left blank, the program just ignores collection 
    date when querying the database.

3. Parameter (What)

    You can select only one parameter at this time. Air pressure is selected
    by default.

4. Output Option

    You can send a query result to either the screen or a file. If you select
    "to screen", the first 50 rows of the query result will be displayed for 
    preview. If you select "to a file", the entire record will be saved 
    in a text file on your local computer. Also, you can choose a delimiter
    that separates column values in each row.  

    Each row contains row number, date, latitude, longitude, 
    selected parameter value, and its unit.