Spatial and temporal variation in weather events critical for boreal agriculture: III Frost and winter time fluctuation

Abstract

In the boreal zone of Europe, differences between the four seasons are considerable. Also, the within-season variation in climatic conditions is substantial. This has many impacts on agriculture that are exceptional when compared to any other environmental zone in Europe. All the meteorological data were based on weather observations made by the Finnish Meteorological Institute. Likelihood (%) for soil frost (≤ 0 °C at 20 cm soil depth) at nine weather stations, and late snow cover (> 1 cm) (10 km × 10 km grid) were estimated for late spring. Probabilities (%) of night frost at the ground surface (March-September) were calculated at nine weather stations by frequencies of the lowest observed night-time temperature: a) between –2 and –5 °C (mild), b) ≤ –5 °C (moderate) and c) ≤ –9 °C (severe). Also, the probabilities (%) of night frost in mid-summer were estimated (≤ –1 °C for at least five hours). Furthermore, a significant shift from mild to below-freezing conditions was measured in winter as a period of at least ten days with daily maximum temperatures above 0°C followed by at least a 10-day period with daily mean temperatures below –5°C in order to characterize high fluctuating winter conditions. All these except late snow cover constitute high risks to crop production. Deep soil frost may postpone sowings, while in advanced springs, night frost may cause damage. For winter crops and perennials, shifts from mild to cold spells outside the growing season are particularly detrimental. Again the data may have many other applications beyond the assessments highlighted in this paper.

Snow cover trends in Finland over 1961–2014 based on gridded snow depth observations

“…Intense snowfall may cause severe problems for traffic and electricity supply (Andreescu and Frost, ; Andersson, ; Juga et al, ; Vajda et al, ; Lehtonen, ), and maintaining sufficient snow removal equipment requires financial resources (Keskinen, ; Lehtonen, ). Snow cover conditions and the changes in them also impact reindeer herding (Hansen et al, , ; Rasmus et al, , ; Turunen et al, ) and boreal agriculture and vegetation, especially in spring (Bjerke et al, ; Peltonen‐Sainio et al, ). On the other hand, the presence of snow in the winter season is essential for recreation and wintertime tourism (Tervo‐Kankare et al, ; Hall, ; Neuvonen et al, ).…”

Risk in agriculture: An overview of the theoretical insights and recent development trends during last decade - A review

“…Peltonen-Sainio with co-authors (Peltonen-Sainio et al 2016a;Peltonen-Sainio et al 2016b;Peltonen-Sainio et al 2016c) published a triptych on the impact of weather events on boreal agriculture. They analysed the impact of temperature changes on crop production (growth, yield, and quality) and animal farming.…”