Divergent trends in the risk of spring frost damage to trees in Europe with recent warming

Abstract

Frost events during the active growth period of plants can cause extensive frost damage with tremendous economic losses and dramatic ecological consequences. A common assumption is that climate warming may bring along a reduction in the frequency and severity of frost damage to vegetation. On the other hand, it has been argued that rising temperature in late winter and early spring might trigger the so called “false spring”, that is, early onset of growth that is followed by cold spells, resulting in increased frost damage. By combining daily gridded climate data and 1,489 k in situ phenological observations of 27 tree species from 5,565 phenological observation sites in Europe, we show here that temporal changes in the risk of spring frost damage with recent warming vary largely depending on the species and geographical locations. Species whose phenology was especially sensitive to climate warming tended to have increased risk of frost damage. Geographically, compared with continental areas, maritime and coastal areas in Europe were more exposed to increasing occurrence of frost and these late spring frosts were getting more severe in the maritime and coastal areas. Our results suggest that even though temperatures will be elevated in the future, some phenologically responsive species and many populations of a given species will paradoxically experience more frost damage in the future warming climate. More attention should be paid to the increased frost damage in responsive species and populations in maritime areas when developing strategies to mitigate the potential negative impacts of climate change on ecosystems in the near future.

Climate change fingerprints in recent European plant phenology

“…Out of the complete phenological data from these countries, For data correction (following e.g. Chen et al, 2018Chen et al, , 2019Ma, Huang, Hänninen, & Berninger, 2019;Vitasse, Signarbieux, & Fu, 2018), we filtered out in each series those observations outside the range median ± 3.5 × MAD (median absolute deviation), which is definitely a more than conservative approach (see Leys, Ley, Klein, Bernard, & Licata, 2013;Miller, 1991), since only the extreme values considered absolutely wrong were excluded (in our case less than 0.7% of the data).…”

Observed Northward Migration of Agro‐Climate Zones in Europe Will Further Accelerate Under Climate Change

“…Nevertheless, the area affected by subzero temperatures after the beginning of thermal growing season is an important factor to consider here; while this area is expected to decrease in the maritime and the Mediterranean zones, no change or even moderate increase is expected in the eastern and northern European climate zones ( Figure 5). Phenologically responsive species might therefore experience more frost damage in the future warming climate due to earlier onset of growing season (Ma et al, 2018). This conundrum could delay the expansion of agricultural production toward the North for several decades (Peltonen-Saino, 2009), until climate gets warm enough that the probability of late frost is very low.…”

Assessing the response of forest productivity to climate extremes in Switzerland using model-data fusion

“…Still, significant reduction in NPP on a large area (up to 21% for P. abies and 15% for F. sylvatica) in drought years provides incentive to reconsider the current forest management strategies and favor more drought tolerant genotypes of present tree species (Fréjaville, Fady, Kremer, Ducousso, & Garzón, 2019), or alternative species at the lower elevations. Furthermore, reducing low-temperature constraints without necessarily reducing the probability of damaging late frosts (due to advanced phenology; Ma, Huang, Hänninen, & Berninger, 2019), our results suggest that F. sylvatica may experience a stronger reduction in NPP and potentially increased mortality in the future.…”