Frost occurring in late summer/autumn; see there
Climatic condition at a temperature below 0 °Celsius or 32 °Fahrenheit. In general, the air temperature is measured at the height of 1.25 meters above the ground; at this height, temperatures are always slightly higher than at ground level. In meteorology, frost at the height of the ground is called ground frost. Basically, a distinction is made between radiation fro st and adjective frost. Radiant frost occurs on dry clear nights with no wind, when the absence of clouds, fog or haze allows heat radiated from the ground or plant tissue to escape unhindered into the atmosphere. The coldest (and heaviest) air sinks to the ground and collects on the surface and preferentially in low-lying depressions. The adjective (meaning "attached") frost results from the influx of already cooled air from elsewhere. This can be from very distant areas such as through a long valley.
Some protection can already be achieved when the vineyards are planted by taking appropriate measures. A slope from which the cold air drains off to lower areas (air drainage), as well as high forms of cultivation are of great advantage. Low-lying and flat areas are most at risk. Frost control in vineyards is achieved by wind machines (or even by helicopters), which artificially induce mixing with the warmer air in the upper layers. Warming smoke stoves, large heaters and similar means are also used. Artificial sprinkling can cause direct warming of the vines and the soil, because heat is released when the water freezes, or a thin layer of ice on parts of the plant also forms a protective coating.
In the northern hemisphere, frost in spring is generally referred to as late frost (also May frost in the relevant month) and in late summer/autumn as early frost. In the course of the annual vegetation cycle, the occurrence of frost poses...