The maritime climate or maritime / oceanic climate is the term used to describe the temperature profile of various types of climate outside the tropics , which are characterized by low seasonal temperature fluctuations below 20 ° C of the monthly average temperatures, as the water of the oceans acts as a temperature buffer ("oceanic temperature profile").
Since the water temperature changes more slowly than the temperature on land due to the large heat capacity , the land near the coast is cooled by the sea in summer and warmed by it in winter. In addition, the comparatively high water vapor content of the air reduces solar radiation. Compared to the continental climate, there are significantly lower temperature differences both between day and night and between summer and winter.
In the climate classification according to Köppen and Geiger , the maritime climate corresponds primarily to type Cfb.
An oceanic climate can be used when the climate of a region is influenced by the presence of a large body of water. In this context, water acts as a moderator; Since water heats up relatively slowly due to its large specific heat capacity and also cools down more slowly, it has a retarding effect in both winter and summer. As a result, the summers in the maritime climate are moderately warm, but the winters are also only moderately cold and always rich in precipitation.
The pure geographical location (coastal location) alone is not an indication of the maritime climate, as the wind direction still has to be taken into account. New York, for example, is located directly on the sea, but like most of the east coast of the USA, it has a continental climate, as the prevailing wind direction is from west to east and the vast land area of North America determines the climate. Most of Europe , however, is influenced by the maritime climate. The deeper you go inland, the more pronounced these climatic differences become; hence the cold Russian winters. Compared to the USA, the climatic difference is also clearly visible: New York is roughly at the same latitude as Naples , and Munich is at the same level as Québec ( Canada ). On average, the winters in European cities are significantly warmer, and extreme weather conditions ( e.g. blizzards ) are rare.
The presence of larger lakes can also affect the climate locally. With the shrinking of the Aral Sea , a summer 2–2.5 ° C warmer and a 1–2 ° C colder winter were measured there. The effect can also be demonstrated on the Bodensee island Mainau .
A rare subtropical highland climate that coincides with a real oceanic climate at a small latitude, here using the example of São Joaquim in Brazil (parallel 28).
Average monthly temperatures and rainfall for São Joaquim
- Petra Demmler: The sea - water, ice and climate , Verlag Eugen Ulmer, 2011. - ISBN 3-80015-864-7 Chapter: Sea and atmosphere ; popular science presentation
- derived from "Climates of the Earth" after Alexander Siegmund and Peter Frankenberg (effective structure) from Westermann Kartographie (ed.): Diercke World Atlas. 1st edition 2008, Bildungshaus Schulbuchverlage, Braunschweig 2009, ISBN 978-3-14-100700-8 , pp. 226–227.
- E. Giese, G., Bahro, D. Betke: Environmental destruction in arid regions of Central Asia (West and East Turkestan). Causes, effects, measures. ( Geographic knowledge , volume 125). Stuttgart 1998.