The ocean’s surface, though sparkling in the sun, serves as a crucial thermometer for our planet’s climate. Sea surface temperature (SST) is meticulously monitored by satellites and buoys in order to provide the most precise readings of the water temperature at the ocean’s surface. When we refer to “sea surface” temperature, we are speaking about the temperature at the very top layer – from just a few millimeters to a few centimeters below the surface. As you delve deeper into the ocean, the water temperature gradually decreases.
Sea surface temperatures can exhibit significant variations worldwide. Near the equator, SSTs can soar as high as 85 degrees Fahrenheit, whereas temperatures near the poles can plummet to the upper 20s. Some regions maintain relatively stable temperatures, while others experience dramatic fluctuations depending on the season and cloud cover.
Fluctuations in SST have profound implications for weather patterns, ocean currents, and marine ecosystems. For example, elevated sea surface temperatures can lead to heightened evaporation, resulting in more intense and frequent storms. This phenomenon is particularly evident in tropical regions, where warm water serves as fuel for tropical systems like hurricanes. Research has shown that increased evaporation can generate stronger and rainier tropical storms capable of unleashing unprecedented amounts of rainfall from a single event.
The monitoring of sea surface temperatures is crucial for comprehending global climate phenomena such as El Niño and La Niña. El Niño, characterized by warmer SSTs in the central and eastern equatorial Pacific Ocean, can trigger widespread weather disruptions, including heavy rainfall and droughts across various regions. Conversely, La Niña, distinguished by cooler SSTs, tends to provoke opposite effects, such as heightened hurricane activity in the Atlantic and drier conditions in the southeastern United States.
SST also plays a pivotal role in marine ecosystems. Warmer ocean temperatures can induce coral bleaching, disrupting marine habitats and impacting the fishing industry. Furthermore, alterations in SST can influence the distribution of fish species, thereby impacting local economies dependent on fishing.
By monitoring changes in SST, scientists can enhance their ability to forecast extreme weather events and anticipate their potential impacts on communities and ecosystems.
Jennifer Gray, a weather and climate writer for weather.com, has been covering major weather and climate stories globally for the past two decades.
