Vai al contenuto
Top Sail
7. Meteorologia

Fronti e depressioni

Fronts and depressions · 35 min

Studia Ripassa

Scheda 1 di 13

Air masses

Le masse d'aria

Air masses: polar maritime from the north-west, polar continental from the east, tropical continental from North AfricaBritishIslesPolar maritimefrom the NW, over the seamoist, heated from below:showers and clear spellsPolar continentalfrom the E or NE, over landdry,very cold in winterTropical continentalfrom North Africa, in summerhot and dryN
The textbook example: air masses arriving over the British Isles. North is at the top.
  • An air mass is a large body of air that takes on the character of the area where it formed.
  • Maritime = has crossed the sea, moist. Continental = has crossed land, dry.
  • Continental air masses change little on their journey; maritime ones are modified a lot.
  • To find out which air mass is arriving, follow the isobars back to where the wind originates.

Watch out. The textbook examples are written for the UK. In the Mediterranean the air masses and the directions they come from are different.

Air mass massa d'aria|Polar maritime polare marittima|Polar continental polare continentale|Tropical continental tropicale continentale

Capitolo successivoLa radio VHF e i segnali di soccorso →

Fonti: RYA Yachtmaster (pubblicazione RYA), pp.68-77 (principi, Coriolis, depressioni, fronti, passaggio); RYA Day Skipper (pubblicazione RYA), PDF pp.34-36; YM5 - Elements of Weather.pptx, slide 12 corretta, Buys Ballot, velocità dei sistemi; RYA Weather Handbook (Chris Tibbs), sezioni Buys Ballot e depressioni; Video Air Masses, depressions, fronts, Precipitation (cartella Meteo); MetLink, Royal Meteorological Society, Weather systems; Shipping forecast workshop (metlink.org); Met Office, How to read synoptic weather charts (weather.metoffice.gov.uk); Britannica e SKYbrary, Buys Ballot's law