Katharine B. Perry
To practice frost protection successfully, one must understand the meteorology that creates freeze events. The sun's radiant energy warms the soil and trees in an orchard. When the soil and fruit trees become warmer than the air, they pass heat to the air by conduction. Through convective mixing, i.e., the warm air near the surface rising and being replaced by cooler air from above, hundreds of meters of the lower atmosphere are warmed. The soil and trees may also radiate heat into the atmosphere. Clouds and carbon dioxide can absorb or reflect some of this heat, trapping it near the surface. This is known as the greenhouse effect.
At night, with no incoming heat to warm the orchard, fruit trees lose heat through radiation and conduction until they are cooler than the surrounding air. The air then passes heat to the soil and trees, and the lower atmosphere cools. This creates an inversion, in which the temperature increases with altitude. The warmer air in the upper part of an inversion is an important source of heat for some frost protection methods.
Was this article helpful?
You Might Just End Up Spending More Time In Planning Your Greenhouse Than Your Home Don’t Blame Us If Your Wife Gets Mad. Don't Be A Conventional Greenhouse Dreamer! Come Out Of The Mould, Build Your Own And Let Your Greenhouse Give A Better Yield Than Any Other In Town! Discover How You Can Start Your Own Greenhouse With Healthier Plants… Anytime Of The Year!