53:078 Principles of Hydrology (Spring 2004)
Problem #6
Missing Precipitation for Iowa City (NCDC web site)

Station ID	Station Name
131314	Cedar Rapids Airport
138266	Tipton 4 NE
138688	Washington
134101	Iowa City

1. Obtain basic data for the four stations from the National Climatic Data Center (NCDC) web site (you must access this site from a computer with a *.edu domain address to get these data at no charge).  Record the station location (latitude/longitude), total precipitation (in inches) for May 2003, and the departure from normal (in inches).  To do this:
   • Go to the National Climatic Data Center (NCDC) web site. 
   • Select the Weather/Climate Events, Information, & Assessment icon.  
   • Select Get/View Online Data from the list.
   • Select Monthly from the Surface Data list.
   • Select Annual Climate Summaries--Select by Station (Cooperative Network). 
   • Choose a Iowa from the state list.  Select the stations from the list.
   • For each station, select 2003 from the list and press Annual Climate Summary.  Record the station location, and total precipitation and departure from normal for May 2003.
2. Determine the 30-year "normal" precipitation (in inches) for May the four stations.  Note that the departure from normal (for May 2003) is equal to the total precipitation (for May 2003) minus the normal precipitation (unknown).
3. Assume that the measurement at the Iowa City station is "missing".  Estimate May 2003 precipitation (in inches) for the missing station using the uniform weighting method.
4. Assume that the measurement at the Iowa City station is "missing".  Estimate May 2003 precipitation (in inches) for the missing station using inverse distance squared weighting.  You can compute the distance between the stations using the Latitude/Longitude Distance Calculator .
5. Assume that the measurement at the Iowa City station is "missing".  Estimate May 2003 precipitation (in inches) for the missing station using the Normal Ratio method.