TERMIUM Plus^®

Fiche 1,  Justifications,  Anglais

Record number: 1, Textual support number: 1 CONT

Radiant frosts occur when large amounts of clear, dry air moves into an area and there is almost no cloud cover at night. During these times, the plants, soil, and other objects which are warmer than the very cold night sky will "radiate" their own heat back to space and become progressively colder. In fact, the plants cool (by radiating their heat) themselves to the point that they can cause their own damage. The plant tissues which are directly exposed to the sky become the coldest. These radiation losses can cause the buds, blossoms, twigs, leaves, etc. to become 1 - 2°C colder than the surrounding air which radiates very little of its heat. ... The amount of heat lost to wind drift is often at least equal to radiative heat losses that are in the range of 10 to 30 watts per square meter (W/m² ) or more. Consequently, the replacement heat must be greater than the sum of both radiative and advective heat losses during "successful" frost protection activities ...  1, fiche 1, Anglais, - radiative%20heat%20loss

Fiche 1,  Justifications,  Français

Record number: 1, Textual support number: 1 CONT

Les techniques de lutte curative ou de lutte active consistent à modifier le bilan énergétique au moment du gel, soit en limitant les pertes de chaleurs par rayonnement, soit en les compensant par des apports de chaleur. Ces techniques de lutte peuvent se réaliser de différentes manières : - Par écrans solides placés au-dessus des cultures fragiles pour leur envoyer un rayonnement sensiblement égal à celui qu'elles émettent.  1, fiche 1, Français, - perte%20de%20chaleur%20par%20rayonnement

Fiche 1,  Justifications,  Espagnol