GLOSSARY TERMS

Dew Point

The dew point is the temperature at which the air should be cooled to saturation (for up to 100% RH). The dew point is an important measurement used for Forecasts of various climatic factors. First is used to predict the formation of fog. If during the hottest hours of the day, the dew point is very close to the temperatures measured it is likely that during the night are to form fog, clouds low fog or extended. The dew point is also useful to estimate approximate temperature of the night in calm conditions weather (clear skies and no wind) the dew point recorded during the hottest hours of the day from an idea on the temperature minimum we can expect for the night. In the summer also a very high dew point indicates (in specific configurations weather) a greater possibility of intense thunderstorms .

 

Windchill

Windchill is a temperature calculated taking into account the measured temperature and wind speed. The wind has on our body cooling forced. The faster the wind blows stronger than the wind chill is lower (equal outside temperature).
The wind chill is not so much the temperature actually received from our body in the presence of wind and low temperatures.

 

Heat Index

The Heat Index uses as operators for calculating the outdoor temperature and relative humidity for determine the effective temperature felt by the human body in the presence of high temperatures. With a low relative humidity the heat index will be more Low outdoor temperature as sweat evaporates more quickly to cool the body. While a higher moisture index of heat could exceed the outdoor temperature as sweat evaporates more slowly and the effective temperature felt by the body (just the Heat Index) is high up to create discomfort and fatigue (eg a temperature of 27 ° C and a humidity of 45%, the temperature felt or Heat Index is less than 43 ° C)

 

Heat Index	Effetti
80–90 °F	Caution - possible fatigue from prolonged sun exposure and physical activity. Continuing the activities could feel cramps
90–106 °F	Extreme caution - cramps and heat exhaustion are possible. The continuation of the After these physical symptoms of a heart attack threatens the subject.
106–129 °F	Danger of cramping and heat stroke even in cases of reduced physical activity to a minimum; remain in the shade as much 'as possible to minimize fatigue and physical effort

 

 Evapotraspiration (ET in inch)

 

The evapotranspiration is a variable or used in agricultural meteorology as a physical quantity index water consumption of crops and is one of the most important variables streamlined management of water used in irrigation; The evapotranspiration is the amount of water (per unit time) that goes from ground to air due to vapor joint transpiration through plants and evaporation, directly from the soil. It is often referred to by the initials ET. The unit measurement is inch, defined as height of the water mass evaporated and transpired, or m ^{3 / h (cubic meter per hectare). As a climatic phenomenon opposite to that of precipitation and Convention is used to make the inch size directly comparable with precipitation.}

The measured value hence a daily quota of water evaporated from soil and from plant, in conditions of drought or heat in a parameter ET growth indicates the need for increased irrigation and plant soil. Low ET instead recommended to adopt a scheme irrigation in the norm for that particular type of plant and / or ground.

 

 

UV Index

The UV index is a international standard measurement of how strong the radiation Ultraviolet (UV) in a particular place and a particular day. One is a scale primarily used in daily forecasts aimed to the public.

The purpose of the survey UV index is to help people protect themselves effectively UV rays, from which excessive exposure causes burns, damage to eyes, cataracts, skin aging and skin cancer. The World Health Organization recommends that people protect themselves (Eg, applying sunscreen to the skin and wear a hat) when the UV index is 3 or higher, see table for complete recommendations.