What Is Sea Surface Temperature?

Sea surface temperatures are measurements taken at the surface of the ocean, ranging from the top millimeter to greater depths, depending on the measurement system used. Government agencies as well as private weather firms and academic weather observatories all collect sea surface temperature (SST) data. It can be used in meteorological predictions as well as studies on ocean health and the weather. The world's oceans have a profound impact on climate patterns, and studying them can provide important insight into various weather phenomena.

There are a number of ways to collect sea surface temperature data. One option is using a thermometer directly at the source. Observing stations can also collect data on wave height, turbidity, and other topics of interest. The information typically transmits remotely to a collection site to make it easier to collate data. When a weather station fails to transmit or appears to be generating errors, a technician can visit it to determine what kind of service it may need.

Weather satellites can also gather sea surface temperature information. Satellite data typically requires a number of sweeps, as cloud cover can interfere with accurate measurements. On maps that use satellite data, periodic dark spots may represent areas that the satellite could not measure because of persistent clouds or other issues. Like base weather stations, satellites typically collect a variety of data in addition to temperatures.

For weather forecasters, sea surface temperature information is very important. The temperature of the ocean has an impact on the air masses over it. Changes in temperature can create a variety of weather conditions, ranging from clear, sunny skies to severe storms. Cyclical seasonal shifts in temperature help explain some weather patterns. Periodic dramatic spikes like warming in the Pacific can cause phenomena like the El Niño weather patterns seen approximately every five years.

Archives of global sea surface temperature data are available through a number of resources. These provide information researchers can apply to extended climate studies. Some annual shifts in temperature are normal, as are larger cyclical patterns that may appear more infrequently. Researchers who want to know if they are seeing a trend or abnormality need to be able to refer to old data to learn more about how the ocean usually behaves over time. This data can also be helpful for weather modeling, where meteorologists may want to compare predictions with actual behavior in the past to determine their accuracy and reliability.