Location: Soil and Water Management Research
Title: The importance of dewfall and frost in semi-arid water and energy balancesAuthor
Submitted to: Meeting Abstract
Publication Type: Abstract Only Publication Acceptance Date: 3/17/2023 Publication Date: 7/11/2023 Citation: Evett, S.R., Marek, G.W., Colaizzi, P.D., Brauer, D.K., Copeland, K.S., Ruthardt, B.B. 2023. The importance of dewfall and frost in semi-arid water and energy balances [abstract]. 2023 ASABE Annual International Meeting, July 9-12, 2023, Omaha, Nebraska. Paper No. 2300149. Interpretive Summary: Technical Abstract: Most crop models do not attempt to compute crop and soil surface energy and water balances to the degree of complexity that would include dewfall and frost accumulation. It appears that dew and frost are assumed to be minor parts of the energy and water balances and so can be safely ignored. This may be the case during the middle of the growing season when evapotranspiration (ET) rates are relatively large and plant and soil surfaces relatively warmer than during other seasons. Crop models are now, however, being used to model multi-year cropping cycles, including the water balance during the off season when precipitation capture and storage in the soil profile is affected by choice of tillage system, resulting residue cover or cover crop, and other factors that may result in different outcomes in terms of soil water storage at planting time. Detailed analysis of large, precision weighing lysimeter data from Bushland, Texas, has now involved algorithms, backed up by manual intervention, for detecting dew and frost accumulation on a five-minute basis for every day of the year for multiple crops (alfalfa, corn, sunflower, winter wheat) spanning nearly 20 years. Dew and frost accumulation was found to account for up to 40% of daily water balance during the off season, providing motivation for the inclusion of more sophisticated and compete energy and water balance algorithms in crop models. |