Britannica
Sources used in this answer
How can forecasts of frost protect fruit crops?
Created from Britannica articles
using AI.
AI can make mistakes, so verify using Britannica articles.
Weather forecasting
Doppler radars, such as this one operated by the U.S. National Weather Service at New Underwood, South Dakota, extract the Doppler frequency shift of the echo produced by a moving target by noting how much the frequency of the received signal differs from the frequency of the signal that was transmitted.
Accurate weather forecasting is essential for protecting fruit crops from frost damage, as it allows growers to implement timely and often costly protective measures before freezing temperatures occur. By predicting the timing and severity of frost, farmers can prepare their fields and activate specific technologies to mitigate injury to sensitive plant tissues.123
When a frost is forecast, growers may employ several strategies:
- Heating: Using oil-fueled heaters or other heat sources to raise the ambient temperature, which is most effective during nights with a strong temperature inversion.31
- Air Mixing: Utilizing wind machines to break up temperature inversions by mechanically mixing warmer air from above with the colder air near the ground.31
- Sprinkling and Flooding: Applying water via sprinkler irrigation or flooding. As water freezes, it releases latent heat, which helps maintain the plant's temperature at or near the freezing point, preventing the internal cell sap from reaching damaging levels.314
- Soil Management: Techniques such as adding sand to soil or pre-frost irrigation can increase the soil's heat capacity, allowing it to radiate more warmth during the night.34
These interventions are critical for high-value crops, such as citrus fruits, where even a single killing frost can cause significant economic loss.35