Effects of social and climatic factors on building activity in the Czech lands between 1450 and 1950: a dendrochronological analysis

The development of settlement and building activity is the result of socioeconomic, political and demographic changes in the past. However, accurate information on temporal variation in building activity is rather limited. Dendrochronological databases containing dated historical wooden constructions provide an important resource. We used 6514 tree-felling dates to reconstruct building activity in the Czech lands for the period 1450–1950. Comparing felling dates with historical events demonstrated that building activity was negatively associated with intense wars, particularly during the Thirty Years' War (1618–1648). After the Peace of Westphalia (1648), socioeconomic renewal and demographic growth were reflected in an upsurge of building activity, especially ecclesiastical buildings. While the construction of ecclesiastical and noble buildings culminated around the 1720s, rural buildings peaked in the 1780s and the 1820s. Although no direct effect of climate was demonstrated, adverse climatic conditions leading to harvest failures and subsequent famines (e.g. the ‘Hunger Years’ 1770–1772) significantly contributed to declines in building activity. In contrast, a higher number of felling dates were detected when strong and/or frequent windstorms occurred. This study provides a comprehensive understanding of building activity in Central Europe and advocates the use of dendrochronological databases for the investigation of human activities in history.     

An epidemiological approach to determining the risk of road damage due to landslides

Disruption of segments of roads can have a significant impact on the vulnerability of the entire network. Natural disasters are frequent causes of disruptions of this kind. This article focuses on determining the risk of road disruptions due to landslides. Our approach is based on methodology widely used in the field of epidemiology. We had available data on the location of the landslides, the road network and a list of the disrupted road segments. With the use of a 2 × 2 table, we determined the relationship between landslide data and road segment disruptions and derived the risk coefficient based on the number of landslides in the vicinity of the road and its length. The result is a disruption risk map with risk coefficients ranging from 0 to 47.94. In order to distinguish the most risky segments, we calculated a threshold of 12.40 with the use of a risk breakdown in a group of segments without damage. Nineteen percentage (402 km) of the road network in the Zlín region (Czech Republic), where the methodology was applied, is located beyond this threshold. The benefits of this approach stem from its speed and potential to define the most risky areas on which a detailed geomorphologic analysis can be focused.     

Quantitative imaging of the Permo‐Mesozoic complex and its basement by frequency domain waveform tomography of wide‐aperture seismic data from the Polish Basin

In this study we present the workflow and results of 2D frequency domain waveform tomography applied to the global‐offset seismic data acquired in central Poland along a 50‐km long profile during the GRUNDY 2003 experiment. The waveform tomography method allows full exploitation of the wide‐aperture content of these data and produces in a semi‐automatic way both the detailed P‐wave velocity model and the structural image (i.e., perturbations in respect to the starting model). Thirteen frequencies ranging from 4 to 16 Hz were inverted sequentially, gradually introducing higher wavenumbers and more details into the velocity models. Although the data were characterised by relatively large shot spacings (1.5 km), we obtained clear images both of the Mesozoic and Permian sedimentary cover. Velocity patterns indicated facies changes within the Jurassic and Zechstein strata. A high velocity layer (ca. 5500 m/s) was found near the base of Triassic (Scythian), which made the imaging of a deeper layer difficult. Nevertheless, we were able to delineate the base of the Permian (i.e., base of the Rotliegend), which was not possible to derive from conventional common‐depth‐point processing, as well as some deeper events, attributed to the Carboniferous. The sub‐Permian events formed a syn‐form which favoured our previous interpretation of a depression filled with Upper Carboniferous molasse. The validity of the waveform tomography‐derived model was confirmed by well‐log data. Forward ray‐tracing modelling and synthetic seismograms calculations provided another justification for the key structures present in the waveform tomography model.     

How a Sphagnum fuscum‐dominated bog changed into a calcareous fen: the unique Holocene history of a Slovak spring‐fed mire

In general, mires develop by autogenic succession from more groundwater‐fed to more rainwater‐fed. This study from a calcareous mire in the West Carpathians (Slovakia) describes a similar development in the Early Holocene, followed by a reverse development in the Middle and Late Holocene. Pollen, macrofossil and testate amoeba analyses show that the site started as a minerotrophic open fen woodland. After 10 700 cal a BP autogenic succession led to the accumulation of at least 1 m of Sphagnum fuscum peat. Around 9000 cal a BP, as climate could no longer sustain a stable water regime, the bog desiccated and a fire broke out. The fire removed part of the peat layer and as a consequence relative water levels rose, leading to the establishment of a wet minerotrophic swamp carr with Thelypteris palustris, Equisetum sp. and Alnus sp. with extremely slow peat accumulation. After 600 cal a BP, rapid peat accumulation with calcareous tufa formation resumed as a result of anthropogenic deforestation and hydrological changes in the catchment and resulting increased groundwater discharge. At present the mire still hosts a wealth of relict and endangered plant and animal species typical of calcareous fens and fen meadows. Copyright © 2011 John Wiley & Sons, Ltd.     

Analysis of thunderstorm and lightning activity associated with sprites observed during the EuroSprite campaigns: Two case studies

During the summers of 2003 to 2006 sprites were observed over thunderstorms in France by cameras on mountain tops in Southern France. The observations were part of a larger coordinated effort, the EuroSprite campaigns, with data collected simultaneously from other sources including the French radar network for precipitation structure, Meteosat with images of cloud top temperature and the Météorage network for detection of cloud-to-ground (CG) flash activity. In this paper two storms are analyzed, each producing 27 sprite events. Both storms were identified as Mesoscale Convective Systems (MCS) with a trailing stratiform configuration (ST) and reaching a maximum cloud area of ~ 120,000 km². Most of the sprites were produced while the stratiform area was clearly developed and during periods of substantial increase of rainfall in regions with radar reflectivity between 30 and 40 dBZ. The sprite-producing periods followed a maximum in the CG lightning activity and were characterized by a low CG flash rate with a high proportion of + CG flashes, typically around 50%. All sprites were associated with + CGs except one which was observed after a − CG as detected by the Météorage network. This − CG was estimated to have − 800 C km charge moment change. The peak current of sprite-producing + CG (SP + CG) flashes was twice the average value of + CGs and close to 60 kA with little variation between the periods of sprite activity. The SP + CG flashes were further characterized by short time intervals before a subsequent CG flash (median value < 0.5 s) and with clusters of several CG flashes which suggest that SP + CG flashes often are part of multi-CG flash processes. One case of a lightning process associated with a sprite consisted of 7 CG flashes.     

Could Cohesion Policy push EU climate efforts?

The main purpose of this article is to evaluate the extent to which the Cohesion Policy of the EU contributes to its climate change mitigation effort. While climate change mitigation and the EU Cohesion Policy have been both thoroughly studied theoretically, the novelty of the present article lies in an analysis of their mutual relationship. Also, a unique feature of this research is an analysis of the contribution of the Cohesion Policy to climate change mitigation over a period of 20 years, including a comparison of the three last programming periods (2000–2006, 2007–2013 and 2014–2020). The results of this research suggest that, while the beginning of the new millennium saw the Cohesion Policy neglecting the issue of climate change mitigation, the current programming period (2014–2020) placed it among its key priorities. This conclusion is supported by a comprehensive set of data on five selected indicators. This article also displays the results against the perspective of the overall climate change mitigation objectives of the EU.

POLICY RELEVANCE

The present article shows how a policy, which used to be considered rather distant from climate change, progressively adopted climate change mitigation as one of its principal objectives. As such, it provides a practical guidance on the integration of climate change mitigation in other policy areas, which may be applied not only in a supranational organisation but also on a national, regional or local level.     

Confirmation of Cometary Features of Newly Discovered Bodies

The majority of new ground-based discoveries of comets comes from large surveys devoted, predominantly, to Near Earth Asteroids. The first step in distinguishing these newly discovered members of the population of cometary bodies consists inconfirmatory astrometric observations along with detection of their cometaryfeatures. Although both amateur and professional stations take part in suchconfirmatory observations, only some of them do a preliminary analysis of thecometary activity of a particular newly discovered body. A timely recognitionof cometary features of a particular body having an unusual orbit can help inplanning further observing campaigns.A main goals of the Klet Observatory NEO astrometric follow-upprogramme consists of an analysis of possible cometary activity of newlydiscovered unusual bodies. Here, we describe several examples (comets C/1999 S4 (LINEAR) and so on). We also mention an extension of our programme to fainterobjects after the completion ofa new 1-m telescope at the Klet Observatory.     

A search for shocked quartz grains in the Allerød‐Younger Dryas boundary layer

The Younger Dryas impact hypothesis suggests that multiple airbursts or extraterrestrial impacts occurring at the end of the Allerød interstadial resulted in the Younger Dryas cold period. So far, no reproducible, diagnostic evidence has, however, been reported. Quartz grains containing planar deformation features (known as shocked quartz grains), are considered a reliable indicator for the occurrence of an extraterrestrial impact when found in a geological setting. Although alleged shocked quartz grains have been reported at a possible Allerød‐Younger Dryas boundary layer in Venezuela, the identification of shocked quartz in this layer is ambiguous. To test whether shocked quartz is indeed present in the proposed impact layer, we investigated the quartz fraction of multiple Allerød‐Younger Dryas boundary layers from Europe and North America, where proposed impact markers have been reported. Grains were analyzed using a combination of light and electron microscopy techniques. All samples contained a variable amount of quartz grains with (sub)planar microstructures, often tectonic deformation lamellae. A total of one quartz grain containing planar deformation features was found in our samples. This shocked quartz grain comes from the Usselo palaeosol at Geldrop Aalsterhut, the Netherlands. Scanning electron microscopy cathodoluminescence imaging and transmission electron microscopy imaging, however, show that the planar deformation features in this grain are healed and thus likely to be older than the Allerød‐Younger Dryas boundary. We suggest that this grain was possibly eroded from an older crater or distal ejecta layer and later redeposited in the European sandbelt. The single shocked quartz grain at this moment thus cannot be used to support the Younger Dryas impact hypothesis.