Review article: A European perspective on wind and storm damage – from the meteorological background to index-based approaches to assess impacts

Wind and windstorms cause severe damage to natural and human-made environments. Thus, wind-related risk assessment is vital for the preparation and mitigation of calamities. However, the cascade of events leading to damage depends on many factors that are environment-specific and the available methods to address wind-related damage often require sophisticated analysis and specialization. Fortunately, simple indices and thresholds are as effective as complex mechanistic models for many applications. Nonetheless, the multitude of indices and thresholds available requires a careful selection process according to the target sector. Here, we first provide a basic background on wind and storm formation and characteristics, followed by a comprehensive collection of both indices and thresholds that can be used to predict the occurrence and magnitude of wind and storm damage. We focused on five key sectors: forests, urban areas, transport, agriculture and wind-based energy production. For each sector we described indices and thresholds relating to physical properties such as topography and land cover but also to economic aspects (e.g. disruptions in transportation or energy production). In the face of increased climatic variability, the promotion of more effective analysis of wind and storm damage could reduce the impact on society and the environment

Dryland mechanisms could widely control ecosystem functioning in a drier and warmer world

Responses of terrestrial ecosystems to climate change have been explored in many regions worldwide. While continued drying and warming may alter process rates and deteriorate the state and performance of ecosystems, it could also lead to more fundamental changes in the mechanisms governing ecosystem functioning. Here we argue that climate change will induce unprecedented shifts in these mechanisms in historically wetter climatic zones, towards mechanisms currently prevalent in dry regions, which we refer to as ‘dryland mechanisms’. We discuss 12 dryland mechanisms affecting multiple processes of ecosystem functioning, including vegetation development, water flow, energy budget, carbon and nutrient cycling, plant production and organic matter decomposition. We then examine mostly rare examples of the operation of these mechanisms in non-dryland regions where they have been considered irrelevant at present. Current and future climate trends could force microclimatic conditions across thresholds and lead to the emergence of dryland mechanisms and their increasing control over ecosystem functioning in many biomes on Earth.The support of the Israel Science Foundation is acknowledged by J.M.G. (grant number 1796/19), O.A. (1185/17) and E.M. (1053/17). M.B. acknowledges funding through the ÖAW-ESS project ClimGrassHydro (Austrian Academy of Sciences).Peer reviewe

The extremely hot and dry 2018 summer in central and northern Europe from a multi-faceted weather and climate perspective

The summer of 2018 was an extraordinary season in climatological terms for northern and central Europe, bringing simultaneous, widespread, and concurrent heat and drought extremes in large parts of the continent with extensive impacts on agriculture, forests, water supply, and the socio-economic sector. Here, we present a comprehensive, multi-faceted analysis of the 2018 extreme summer in terms of heat and drought in central and northern Europe, with a particular focus on Germany. The heatwave first affected Scandinavia in mid-July and shifted towards central Europe in late July, while Iberia was primarily affected in early August. The atmospheric circulation was characterized by strongly positive blocking anomalies over Europe, in combination with a positive summer North Atlantic Oscillation and a double jet stream configuration before the initiation of the heatwave. In terms of possible precursors common to previous European heatwaves, the Eurasian double-jet structure and a tripolar sea surface temperature anomaly over the North Atlantic were already identified in spring. While in the early stages over Scandinavia the air masses at mid and upper levels were often of a remote, maritime origin, at later stages over Iberia the air masses primarily had a local-to-regional origin. The drought affected Germany the most, starting with warmer than average conditions in spring, associated with enhanced latent heat release that initiated a severe depletion of soil moisture. During summer, a continued precipitation deficit exacerbated the problem, leading to hydrological and agricultural drought. A probabilistic attribution assessment of the heatwave in Germany showed that such events of prolonged heat have become more likely due to anthropogenic global warming. Regarding future projections, an extreme summer such as that of 2018 is expected to occur every 2 out of 3 years in Europe in a +1.5 ∘C warmer world and virtually every single year in a +2 ∘C warmer world. With such large-scale and impactful extreme events becoming more frequent and intense under anthropogenic climate change, comprehensive and multi-faceted studies like the one presented here quantify the multitude of their effects and provide valuable information as a basis for adaptation and mitigation strategies

Data from: Biotic and abiotic modifications of leaf litter during dry periods affect litter mass loss and nitrogen loss during wet periods

1. Decomposition of organic matter in semiarid ecosystems is a key component of the terrestrial carbon (C) cycle. The well-known inaccuracies in predicting litter decay in water-limited regions were lessened by considering solar radiation as an abiotic decay driver of photodegradation. Moreover, exposure to high solar irradiance in dry periods often led to massive facilitation of litter decay in subsequent wet periods (“photoacceleration”), though in many studies this effect was absent. 2. Recently, water vapor and dew were identified as modulators enabling substantial microbial degradation during rainless periods. Here we asked, (i) if the activity of microorganisms modifies litter traits, such as litter quality and microbial community in dry periods, consequently altering the loss of litter mass and nitrogen (N) in wet periods, and (ii) whether it can co-occur with photoacceleration. 3. By successively introducing litter to the field at the beginning and the end of the dry season, we found that microbial activity during the dry season affected litter mass and N loss during the wet season. Low microbial activity in the dry season led to inhibition of mass loss in the wet season, while high microbial activity led to facilitation of mass loss. Microbial activity during the dry season also caused strong inhibition of N loss from litter during the wet season, likely by enhancing the dry-season N loss. A microclimate manipulation experiment using radiation filters showed that microbial activity and exposure to solar radiation jointly modified the litter during the dry season and affected subsequent decay in the wet season. 4. Knowledge of biotic and abiotic modifications of litter during dry periods and their implication for wet periods enhances our understanding of litter decay in semiarid regions. Furthermore, it can improve biogeochemical model predictions of C and N cycling i

Methadone treatment in Ontario after the 1996 regulation reforms. Results of a physician survey

Over two decades of rather restrictive regulations have kept the availability of methadone treatment (MT) at low levels in the province of Ontario, Canada. Regulatory changes in the Province of Ontario in the mid-1990s relaxed relevant authorization and treatment practice guidelines. Subsequently, the number of physicians authorized for methadone treatment and treatment spots increased substantially. A large number of the newly authorized physicians are general/local medical practitioners. This study reports on the results of a survey conducted with the majority of MT prescribing physicians in Ontario authorized at the time of study. Physicians were surveyed on their attitudes and practices with regards to the MT authorization system, treatment approaches, requirements and workload, patient 'stability', additional opiate substitution treatment needs, and with regards to general issues and concerns about the new MT governance system. The article also discusses patterns and differences that were found between physicians when comparing their geographic location, whether they see themselves practicing under a 'harm reduction' or an 'abstinence' approach, and whether they received MT authorization under the old or the new guidelines. It is concluded that the liberalized regulations and the increased incorporation of local physicians seems to provide for an overall more desirable system of governance of MT. However, some relevant concerns about the current system exist and are discussed

Evaluation of Long-Term Radar-Derived Precipitation for Water Balance Estimates: A Case Study for Multiple Catchments in Saxony, Germany

Quality of water balance estimations are strongly dependent on the precipitation input. The key limitation here is typically a lack of spatial representation in precipitation data. Quantitative precipitation estimation (QPE) using radar is recognized as capable to significantly enhance the spatial representation of precipitation compared to conventional rain gauge-based methods by calibrating radar pixels with surrounding rain gauges. However, the measured precipitation is often underestimated due to wind drift or funnel evaporation, particularly in mountainous areas. Thus, a post-correction is required before applying radar precipitation in water balance models. Here, we applied the Richter correction for the first time to a radar-based QPE, to model the water balance in ten catchments in Saxony, Germany. The hydrological responses for the period 2001–2017 from the model were validated with discharge observations. The results show that radar data application yielded reliable simulations of water balance (KGE = 0.53 and 0.70 at daily and monthly resolutions, respectively). However, a simple compensation such as the Richter method to conventional precipitation should be used with caution. This study shows that radar-based precipitation has immense potential to advance quality of the precipitation input to distributed hydrologic models not only for flood events but also for climatological analyses