Water Quality: Temperature

Introduction

The temperature of a body of water influences its overall quality. Water temperatures outside the “normal” range can cause harm to the aquatic organisms that live there. If the water temperature changes by even a few degrees, it could indicate a source of unnatural warming of the water or thermal pollution.

Shade is very important to the health of water because of the warming influences of direct sunlight. Another factor that may affect water temperature is the temperature of the air above the water. The extent of its influence has a great deal to do with the depth of the water. A shallow body of water is more susceptible to changes in temperature than deep water would be. While many factors can contribute to the warming of surface water, few cause it to be cooled. One way water can be cooled is by cold air temperatures. A second, natural method of cooling comes from the introduction of colder water, such as refilling a container directly from a faucet.

In this experiment, you will measure the temperature of a small body of water, such as an aquarium. Then you will monitor the temperature of that body of water for a 24-hour period by taking a temperature reading once each minute.

Objectives

In this experiment, you will

• Use a computer and an NXT to measure temperature.
• Conduct a long-term data collection study.
• Learn why some bodies of water are more vulnerable to temperature changes than others.