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Reading Sea Surface Temperature

One of the ways to detect an El NiƱo event is to look at sea surface temperature (SST). SST can be recorded using instruments on orbiting satellites which measure infrared radiation from the surface of the oceans. This data can be represented on maps in different ways. Researchers map temperature zones using colors to represent areas of temperature, producing what is called a false-color map.

Below is an example of a false-color map of sea surface temperature. Use this map to check your understanding. Then try making your own map of sea surface temperature using real data.

Sea surface temperature map, equitorial Pacific, December 16, 1989

Check your understanding

1. Lines of latitude indicate:

 degrees of temperature.
 degrees north and south of the Equator.
 areas of equal temperature.
 representations of colors to indicate temperature.

2. According to the map, the monthly average sea surface temperature at 5° North and 140° West is approximately:

 30 degrees Celsius (°C).
 28 degrees Celsius (°C).
 26 degrees Celsius (°C).
 24 degrees Celsius (°C).