Taking the Temperature of Water

Student Guide - Global Lab

A. Temperature Over the Water Surface

Materials

temperature probe or thermometer
Data sheet

Procedure

Using the temperature probe or a thermometer, measure the air temperature in several locations over the body of water.

Be sure to measure in both sunny and shady locations

B. Temperatures at Different Depths (water stratification)

Materials

protective gloves
goggles
waterproof digital temperature probe with long wire
or thermometer plus TERC water pump sample collector
GL data sheet

Procedure

1 Find a good location for depth measurements.  (Ideally this would happen from a dock or boat where you would have access to deeper water.)
2 Put on protective gloves if you are sampling near shore.
3 Measure the temperature of the water at the surface by submerging the temperature probe to a depth of 5 cm in several locations.
4 Either weight and lower your digital thermometer or, use the TERC water pump, take water samples at depths of 5 (if you did not do surface testing), 10cm, 50 cm, 100 cm, 150 cm, and (optional) 200 cm, and so on.
Measure the temperature of these water samples in the field using the temperature probe.

Results will include:

 
Temperature Location 1/ 5 cm ______ (degrees Celsius)
  Sunny ____ Shade ____
Temperature Location 1/ 50 cm ______ (degrees Celsius)
  Sunny ____ Shade ____
Temperature Location 1/100 cm ______ (degrees Celsius)
  Sunny ____ Shade ____
Temperature Location 1/200 cm ______ (degrees Celsius)
  Sunny ____ Shade ____
 
Description of location:
 
 
 
Other relevant information:

Research Possibilities include:

• measuring the temperature of other bodies of water at various depths and locations.
• testing for relationships between water temperature and the characteristics of the water. Set up experiments in which you control the size, depth, and turbidity of water in containers.
• comparing the temperature of the water at various locations with the rate of flow at those locations. You do not need to be able to measure the actual rates of flow as long as you know them relative to each other.
• testing for relationships between light intensity just above the water and the temperature of the water near the surface. You can even set up experiments in which you control the amount of light reaching the water.
• hatching brine shrimp eggs in containers of an increasing temperature or light intensity gradient and count the number of hatched young to see the range of tolerance of brine shrimp eggs to temperature or light intensity