Coastal Services Center

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What Is Coastal Climatology?

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Defining "Climate" and "Climatology"

Before discussing coastal climatology, you must first define the terms climate and climatology. Climate has traditionally been defined as the average and variability of meteorological elements, such as precipitation amount or air temperature, at a specific location over a period of time. More modern definitions of climate include extreme weather event data and statistics. (NOAA uses a 30-year average climate normal as defined by the World Meteorological Organization.) Climatology is the scientific study of these averages, their physical causes, and how they vary over time and by region.

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Defining "Coastal" in Coastal Climatology

If you live 50 miles inland from the coast, are you still living in a coastal location? According to the climate of that location, you may be!

The NOAA Coastal Services Center uses the dynamic inland extent of the sea breeze circulation system as a way to define "coastal" in coastal climatology. The sea breeze, which moderates afternoon temperatures, increases relative humidity, and alters wind speed and direction, can be felt up to 50 miles or more from the coast on a given afternoon throughout much of the year. The inland extent of the sea breeze can vary according to weather conditions and long-term climatic patterns. Thus, while a specific town or community may be many miles inland from the coast, the community can still be affected by coastal climate.

What is Coastal Climatology?

Coastal climatology is the study of climate in the coastal zone. Interactions between the land, water, and atmosphere produce highly complex weather and ocean patterns unique to the coastal zone and contribute to the climate of a particular coastal region.

Contributions to a unique climatology of the coastal zone:

• Afternoon sea breezes and associated thunderstorms
• Enhanced winds and precipitation due to coastal fronts
• Increased precipitation during the winter due to moisture from relatively warm waters
• Banks of dense sea or lake fog that lower visibility to near zero
• Upwelling of cool subsurface water to the ocean surface
• Changes in coastal bathymetry that lead to the development of rip currents

Examples of coastal climatology information:

• Past data records and calculated averages such as the normal August temperature for a selected city
• Typical weather patterns such as nor'easters that develop and move up the East Coast of the U.S.
• Data on extreme weather events such as floods or drought
• Seasonal outlooks such as predictions of a cooler-than-average winter
• Long-range predictions such as the change in sea level over the next decade