Climatology of the synchronism of late spring frost with sensible phenological stages of five major horticultural crops in Quebec

Citation

Denault, J.-T., Benjamin, L.-D., Lord, É., Boivin, C., Ricard, S. & Bourgeois, G. 2023. Climatology of the synchronism of late spring frost with sensible phenological stages of five major horticultural crops in Quebec. Poster presented at the 57th Canadian meteorological and oceanographic society congress. St.John's, NL.

Plain language summary

Late spring frosts can cause significant damage to major horticultural crops, especially when these are at particularly frost-sensitive stages of development. In order to prevent damage associated with freezing, irrigation is a commonly used practice. However, this practice requires large volumes of water, early in the growing season.
This project assesses the frequency of frost events that may have occurred in recent decades when the plant was vulnerable to these temperatures. This number corresponds the number of times that protective equipment should be used and, thus, can be used to estimate the water needs associated with crop protection late spring frost. Estimates are available for strawberries, raspberries, blueberries, grapes and cranberries for which crop development models were calibrated for Quebec.

Abstract

Synchronism of late spring frost with sensible phenological stages may lead to significant damages to the major horticultural crops in Quebec. In order to prevent frost associated damages, irrigation is a commonly used practice requiring important volumes of water early in the growing season. This project evaluates the climatology associated with “flower-frost” synchronism in order to provide an estimation of current and future water needs related to frost protection for strawberries, raspberries, blueberries, grape vines and cranberries.
Different phenological models developed at AAFC, using calibrated models of thermal accumulation (degree-days), and gridded daily temperature values were used in order to determine the occurrence of “flower-frost” synchronism. Two historical climate datasets (NRCan, ANUSPLIN and the Canadian Regional Deterministic Reanalysis System v2.1) were evaluated to estimate the influence of the climate information on frost damage risks.
Even though the reanalysis shows interesting patterns in regions where the density of weather stations is small, the small cold bias observed when compared to weather station estimates reinforce the need to recalibrate the phenological model thresholds with the observations dates so that it can be used to estimate the “flower-frost” synchronism.
ANUSPLIN data was used to get the climatology statistics for the five major horticultural crops observed in the recent climatic periods. Evaluation of the frost length using hourly values from a subset of weather stations was used as a proxy to determine the average water needs during an event.