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Snowmelt runoff serves both human needs and ecosystem services and is an important parameter in operational forecasting systems. Sentinel-1 synthetic-aperture-radar (SAR) observations can estimate the timing of melt within a snowpack; however, these estimates have not been applied on large spatial scales. Here we present a workflow to combine Sentinel-1 SAR and optical data from Landsat-8 and Sentinel-2 to estimate the onset and duration of snowmelt in the La Joie Basin, a 985 km2 watershed in the southern Coast Mountains of British Columbia. A backscatter threshold is used to infer the point at which snowpack saturation occurs and the snowpack begins to produce runoff. Multispectral imagery is used to estimate snow-free dates across the basin to define the end of the snowmelt period. SAR estimates of snowmelt onset form consistent trends in terms of elevation and aspect on the watershed scale and reflect snowmelt records from continuous snow water equivalence observations. SAR estimates of snowpack saturation are most effective on moderate to low slopes (< 30∘) in open areas. The accuracy of snowmelt duration is reduced due to persistent cloud cover in optical imagery. Despite these challenges, snowmelt duration agrees with trends in snow depths observed in the La Joie Basin. This approach has high potential for adaptability to other alpine regions and can provide estimates of snowmelt timing in ungauged basins.

Introduction: Communicating risk to the public continues to be a challenge for public health practitioners working in the area of climate change. We conducted a scoping literature review on the evaluation of risk communication for extreme weather and climate change to inform local public health messaging, consistent with requirements under the Ontario Public Health Standards (OPHS), which were updated in 2018 to include effective communication regarding climate change and extreme weather. Methods: Search strategies were developed by library information specialists and used to retrieve peer-reviewed academic and grey literature from bibliographic databases (Medline, Embase, Scopus and CINAHL) and Google country specific searches, respectively. The search strategy was validated through a workshop with experts and community stakeholders, with expertise in environment, health, emergency management and risk communication. Results: A total of 43 articles were included. These articles addressed issues such as: climate change (n = 22), flooding (n = 12), hurricane events (n = 5), extreme heat (n = 2), and wild fires (n = 2). Studies were predominantly from the US (n = 14), Europe (n = 6) and Canada (n = 5). Conclusion: To meet the OPHS 2018, public health practitioners need to engage in effective risk communication to motivate local actions that mitigate the effects of extreme weather and climate change. Based on the scoping review, risk communication efforts during short-term extreme weather events appear to be more effective than efforts to communicate risk around climate change. This distinction could highlight a unique opportunity for public health to adapt strategies commonly used for extreme weather to climate change.

Introduction. La communication des risques au public demeure un défi pour les professionnels de la santé publique oeuvrant dans le secteur des changements climatiques. Nous avons effectué un examen de la portée de la littérature sur l’évaluation de la communication des risques en présence de phénomènes météorologiques extrêmes et de changements climatiques dans le but de créer des messages en matière de santé publique à l’échelle locale conformes aux exigences des Normes de santé publique de l’Ontario (NSPO). Ces normes ont été mises à jour en 2018 pour inclure la communication efficace de messages sur les changements climatiques et les phénomènes météorologiques extrêmes. Méthodologie. Des spécialistes en bibliothéconomie ont établi des stratégies de recherche pour recenser les publications universitaires revues par des pairs et la littérature grise dans plusieurs bases de données bibliographiques (Medline, Embase, Scopus et CINAHL) et dans les moteurs de recherche Google nationaux. Cette stratégie de recherche a été validée lors d’un atelier avec des experts et des intervenants communautaires spécialisés en environnement, en santé, en gestion des urgences et en communication des risques. Résultats. Au total, 43 articles ont été retenus. Ces articles traitaient principalement des changements climatiques (n = 22), des inondations (n = 12), des ouragans (n = 5), de la chaleur extrême (n = 2) et des incendies de forêt (n = 2). Les études provenaient principalement des États-Unis (n = 14), de l’Europe (n = 6) et du Canada (n = 5). Conclusion. Pour satisfaire aux NSPO de 2018, les professionnels de la santé publique doivent communiquer efficacement les risques afin d’encourager la prise de mesures efficaces à l’échelle locale aptes à atténuer les effets des phénomènes météorologiques extrêmes et des changements climatiques. D’après notre examen de la portée, les efforts de communication des risques durant les phénomènes météorologiques extrêmes de courte durée semblent plus efficaces que les efforts de communication des risques liés aux changements climatiques. Cela pourrait constituer une occasion unique pour les intervenants en santé publique d’appliquer les stratégies couramment utilisées pour les phénomènes météorologiques extrêmes aux changements climatiques.

Snowmelt runoff serves both human needs and ecosystem services and is an important parameter in operational forecasting systems. Sentinel-1 synthetic-aperture-radar (SAR) observations can estimate the timing of melt within a snowpack; however, these estimates have not been applied on large spatial scales. Here we present a workflow to combine Sentinel-1 SAR and optical data from Landsat-8 and Sentinel-2 to estimate the onset and duration of snowmelt in the La Joie Basin, a 985 km2 watershed in the southern Coast Mountains of British Columbia. A backscatter threshold is used to infer the point at which snowpack saturation occurs and the snowpack begins to produce runoff. Multispectral imagery is used to estimate snow-free dates across the basin to define the end of the snowmelt period. SAR estimates of snowmelt onset form consistent trends in terms of elevation and aspect on the watershed scale and reflect snowmelt records from continuous snow water equivalence observations. SAR estimates of snowpack saturation are most effective on moderate to low slopes (< 30 ∘) in open areas. The accuracy of snowmelt duration is reduced due to persistent cloud cover in optical imagery. Despite these challenges, snowmelt duration agrees with trends in snow depths observed in the La Joie Basin. This approach has high potential for adaptability to other alpine regions and can provide estimates of snowmelt timing in ungauged basins. [ABSTRACT FROM AUTHOR]

Trade-offs between growth and stress tolerance in plants may limit the possible phenotypes that can evolve or be selected. Such limits would have important implications for tree breeding. We examined evidence for trade-offs between growth and stress tolerance, particularly cold and drought tolerance, in 56 families of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) from wild stand and seed orchard seed with a range of predicted growth rates. Families were assessed in field and controlled-environment experiments for growth and key physiological traits related to abiotic stress response. In the field, family growth was negatively correlated with fall and spring cold hardiness, indicating a trade-off between growth and cold hardiness. Combined results from field and controlled-environment experiments showed lower stomatal conductance and higher water potential in fast-growing families, indicating greater water conservation; thus no evidence existed for a growth - drought hardiness trade-off. Multivariate regression trees of normalized family means of growth and physiological parameters in the field split the families primarily by an index of continentality. Continental families had greater growth, survival, and fall hardiness than coastal families. We conclude that selection pressures in Douglas-fir have resulted in a trade-off between cold hardiness and high vigour, but little evidence exists for a trade-off between growth and drought hardiness. Resume: Les compromis entre la croissance et la tolerance au stress chez les plantes peuvent limiter les phenotypes potentiels qui peuvent evoluer ou etre selectionnes. De telles limites auraient d'importantes consequences pour l'amelioration des arbres. Nous avons examine les indices de compromis entre la croissance et la tolerance au stress, particulierement la tolerance au froid et a la secheresse, dans 56 familles de douglas de Menzies (Pseudotsuga menziesii (Mirb.) Franco) provenant de graines de peuplements forestiers et de vergers a graines et representant une gamme de taux de croissance predits. Les familles ont ete evaluees dans des experiences au champ et en milieu controle pour la croissance et les caracteres physiologiques cles relies a la reaction aux stress abiotiques. Au champ, la croissance des familles etait negativement correlee avec la resistance au froid a l'automne et au printemps, ce qui est le signe d'un compromis entre la croissance et la resistance au froid. Les resultats combines des experiences au champ et en milieu controle revelent que la conductance stomatique est plus faible et le potentiel hydrique plus eleve dans les familles a croissance rapide, ce qui est l'indice d'une plus grande conservation de l'eau; il n'y avait par consequent pas de signe de compromis entre la croissance et la resistance a la secheresse. Des arbres de regression multivariee de la moyenne familiale normalisee des parametres physiologiques et de croissance au champ separaient les familles principalement par un indice de continentalite. Les familles continentales avaient une plus forte croissance, un taux de survie plus eleve et une plus grande resistance au gel automnal que les familles cotieres. Nous concluons que les pressions de selection chez le douglas de Menzies ont eu comme resultat un compromis entre la resistance au gel et une forte vigueur mais il y a peu d'indices qu'il existe un compromis entre la croissance et la resistance a la secheresse. [Traduit par la Redaction], Introduction J.P. Grime's C-S-R triangle theory (Grime 1977) proposed that plant life history strategies be classified as competitor (C), stress tolerator (S), and ruderal (R). Simply stated, competitors have rapid [...]

Snowmelt runoff serves both human needs and ecosystem services and is an important parameter in operational forecasting systems. Sentinel-1 Synthetic Aperture Radar (SAR) observations can estimate the timing of melt within a snowpack; however, these estimates have not been applied on large spatial scales. We present here a workflow to fuse Sentinel-1 SAR and optical data from Landsat-8 and Sentinel-2 to estimate the onset and duration of snowmelt in the Lajoie Basin, a large watershed in the Southern Coast Mountains of British Columbia. A backscatter threshold is used to infer the point at which snowpack saturation occurs, and the snowpack begins to produce runoff. Multispectral imagery is used to estimate snow free dates across the basin to define the end of the snowmelt period. SAR estimates of snowmelt onset form consistent trends by elevation and aspect on the watershed scale and reflect snowmelt records from continuous SWE observations. SAR estimates of snowpack saturation are most effective on moderate to low slopes (< 30°) in open areas. The accuracy of snowmelt durations is reduced due to persistent cloud cover in optical imagery. Despite these challenges, snowmelt durations agree with trends in snow depths observed in the Lajoie. This approach has high potential for adaptability to other alpine regions and can provide estimates of snowmelt timing in ungauged basins. [ABSTRACT FROM AUTHOR]

Introduction: Communicating risk to the public continues to be a challenge for public health practitioners working in the area of climate change. We conducted a scoping literature review on the evaluation of risk communication for extreme weather and climate change to inform local public health messaging, consistent with requirements under the Ontario Public Health Standards (OPHS), which were updated in 2018 to include effective communication regarding climate change and extreme weather. Methods: Search strategies were developed by library information specialists and used to retrieve peer-reviewed academic and grey literature from bibliographic databases (Medline, Embase, Scopus and CINAHL) and Google country specific searches, respectively. The search strategy was validated through a workshop with experts and community stakeholders, with expertise in environment, health, emergency management and risk communication. Results: A total of 43 articles were included. These articles addressed issues such as: climate change (n = 22), flooding (n = 12), hurricane events (n = 5), extreme heat (n = 2), and wild fires (n = 2). Studies were predominantly from the US (n = 14), Europe (n = 6) and Canada (n = 5). Conclusion: To meet the OPHS 2018, public health practitioners need to engage in effective risk communication to motivate local actions that mitigate the effects of extreme weather and climate change. Based on the scoping review, risk communication efforts during short-term extreme weather events appear to be more effective than efforts to communicate risk around climate change. This distinction could highlight a unique opportunity for public health to adapt strategies commonly used for extreme weather to climate change. [ABSTRACT FROM AUTHOR]