Effectiveness of wind machines: Frost protection by ramjet or conventional wind machines in deciduous orchards depends on the strength of the inversion

Goodall, G; Angus, D; Leonard, A; Brooks, F

Effectiveness of wind machines: Frost protection by ramjet or conventional wind machines in deciduous orchards depends on the strength of the inversion

Authors

G. E. Goodall
D. E. Angus
A. S. Leonard
F. A. Brooks

Authors Affiliations

G. E. Goodall, Farm Advisor, Santa Barbara County, University of California, participated in earlier wind machine tests in this project in citrus and was on loan to the Department of Agricultural Engineering for these studies; D. E. Angus, Assistant Specialist in Agriultural Engineering, University of California, Davis, conducted the frost research program of the Division of Meteorological Physics, Commonwealth Scientific and Industrial Research Organization, Australia, and was granted leave to cooperate in these studies in California; A. S. Leonard is Specialist in Agricultural Engineering, University of California, Davis; F. A. Brooks is Agricultural Engineer, University of California, Davis.

Publication Information

Hilgardia 11(8):7-9. DOI:10.3733/ca.v011n08p7. August 1957.

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Abstract

When the atmosphere 40' to 50' above ground is 13°F or more warmer than it is a few feet above the soil surface, the temperature inversion condition—in frost protection research—is considered to be strong. When the temperature difference is less than about 5°F the inversion is considered weak. The weak inversions usually found in the deciduous orchards on the floor of the Sacramento Valley appear to limit the usefulness of wind machines for frost protection unless additional heat is supplied from orchard heaters.

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