1. Dept. of Agriculture Engineering, Univ. of Catania, Via S. Sofia 100, 95123 Catania, Italy (corresponding author).
2. Subtropical Horticulture Farm Advisor, Tulare County Cooperative Extension, University of California, Agriculture Building, 4437 S. Laspina St., Ste. B, Tulare, CA 93274.
3. Biometeorologist, Dept. Land Air and Water Resources (LAWR), Univ. of California, Davis, One Shields Ave., Davis, CA 95616-8627.