One of the many factors of weather or in the long-term weather conditions of the climate, Strong air movements can affect both positively and negatively in the vineyards. Hot, dry winds, such as those in Australia, or the Scirocco wafting from the Sahara towards the Mediterranean and reaching southern European winegrowing areas, can be dangerous. Likewise feared are cold winds in valleys, such as the notorious Mistral on the southern side Rhone, At high stress can also occur in the vine wind stress, resulting in lower yields, impaired growth of shoots, Deciduous and grapevines. As a protection against the wind namely from the vines the stomata in the Scroll closed, which is a limited photosynthesis thereby causing later ripening of the grapes.
By lower wind strength also remains humidity better preserved between the vines, which can be particularly important in dry areas. Harmful effects are caused by plant covers (Protective pants) made of plastic or windbreaker (barriers from vegetation or artificial facilities) prevented. So-called wind machines (fans) whirl up the cold soil air and mix it with warmer layers above it. This fights the dreaded radiation frost (frosty nights with no wind), for example in California Napa Valley is in use. Damp sea winds can exert a positive moderating influence in arid and low rainfall wine regions such as Portugal, California and South Australia. See also below frost. drought. thunderstorm. hail and climate,