The Moravian missionaries at the Labrador coast and their centuries-long contribution to instrumental meteorological observations

The history of instrumental meteorological observations in Labrador/Nunatsiavut, Canada, began in August 1771 when the Unitas Fratrum, also known as the “Moravian Brethren”, established a mission among the Inuit on the Labrador coast. The Brethren named this place “Nain” after a city mentioned in the New Testament of the Bible. The missionaries included learned men, trained in the natural sciences, and in October of that same year they began to undertake instrumental meteorological observations. These observations have been continued, in one form or another, to the present day. As will be shown in this paper, the year 1771 thus marks the beginning of a long time series of meteorological observations from Labrador. The authors of this paper are currently researching the climatic history of the Labrador/Nunatsiavut region by tracing the meteorological observations of the Moravian missionaries to be found in scientific publications of the eighteenth, nineteenth and twentieth centuries. As will be demonstrated, the records of these observations in Labrador go through several stages; from being almost completely forgotten, to being published and republished in the main international meteorological journals. In this latter context, it may be said that the channels for the distribution of this knowledge are still being charted; this process involves tracking contacts between the Moravian Church and their sympathisers, as well as between the Church and contemporary scientists. This paper seeks to elucidate knowledge of these old records by placing them in the context of the research field of historical climatology and, at the same time, to honour the Moravian missionary observers for their valuable contribution to knowledge of past variations in climate.     

Nitrogen cycling in the German Bight (SE North Sea) — Clues from modelling stable nitrogen isotopes

Nitrogen isotope values (δ¹⁵N) of surface sediments in the German Bight of the North Sea exhibit a significant gradient from values of 5–6‰ of the open shelf sea to values above 11‰ in the German Bight. This signal has been attributed to high reactive N (N_r) loading enriched in ¹⁵N from rivers and the atmosphere. To better understand the processes that determine the intensity and spatial distribution of δ¹⁵N anomalies in surface sediments, and to explore their usefulness for reconstructions of pristine N-input from rivers, we modeled the cycling of the stable isotopes ¹⁴N and ¹⁵N in reactive nitrogen through the ecosystem of the central and southern North Sea (50.9–57.3°N, 3.4°W−9.2°E) for the year 1995. The 3D-ecosystem model ECOHAM amended with an isotope-tracking module was validated by δ¹⁵N data of surface sediments within the model domain. A typical marine value (δ¹⁵N_nitrate=5‰) was prescribed for nitrate advected into the model domain at the seaside boundaries, whereas δ¹⁵N_nitrate of river inputs were those measured bi-monthly over 1 year; δ¹⁵N values of atmospheric deposition were set to 6‰ and 7‰ for NO_x and NH_y, respectively. The simulated δ¹⁵N values of different nitrogen compounds in the German Bight strongly depend on the mass transfers in the ecosystem. These fluxes, summarized in a nitrogen budget for 1995, give an estimate of the impacts of hydrodynamical and hydrological boundary conditions, and internal biogeochemical transformations on the nitrogen budget of the bight.     

Movement of logperch—the obligate host fish for endangered snuffbox mussels: implications for mussel dispersal

Unionid mussels are highly imperiled and the survival of their local populations is linked to the availability and dispersal potential of their host fish. We examined the displacement distance of logperch (Percina caprodes), which are obligate host fish for endangered snuffbox mussels (Epioblasma triquetra), to determine the dispersal potential by fish. Logperch in the Sydenham River, Ontario, Canada, were electrofished and marked with visible implant elastomer on five sampling dates during the gravid period of E. triquetra. The majority of all recaptures (82%) of P. caprodes occurred within 30 m of their original capture location, with a mean displacement distance of 13 ± 3 m (mean ± standard error, n = 28). These results were consistent with a review of movement studies of small benthic host fish (i.e., darters and sculpins), which revealed average fish displacement distances of 37 ± 19 m (n = 14 species; range: 4–275 m). However, significantly greater movement distances were also found and the maximum displacement distance increased significantly with the spatial extent of the study and with the duration of the study. These results indicate that many P. caprodes remain in a small area, which could restrict the dispersal and (re)colonization potential of E. triquetra. Further studies are needed to determine the dispersal potential of mussels via host fish, which may be important for maintaining the connectivity among unionid populations.     

Acceleration Phase of Coronal Mass Ejections: II. Synchronization of the Energy Release in the Associated Flare

We analyze the relationship between the acceleration of coronal mass ejections (CMEs) and the energy release in associated flares, employing a sample of 22 events in which the CME kinematics were measured from the pre-eruption stage up to the post-acceleration phase. The data show a distinct correlation between the duration of the acceleration phase and the duration of the associated soft X-ray (SXR) burst rise, whereas the CME peak acceleration and velocity are related to the SXR peak flux. In the majority of events the acceleration started earlier than the SXR burst, and it is usually prolonged after the SXR burst maximum. In about one half of the events the acceleration phase is very closely synchronized with the fastest growth of the SXR burst. An additional one quarter of the events may be still considered as relatively well-synchronized, whereas in the remaining quarter of the events there is a considerable mismatch. The results are interpreted in terms of the feedback relationship between the CME dynamics and the reconnection process in the wake of the CME.     

Fluoride occurrence in publicly supplied drinking water in Estonia

A study was undertaken to examine the content and spatial distribution of fluoride in drinking water. Water samples (735) from public water systems covering all Estonian territory were analysed using SPADNS method. In order to specify the natural source of fluoride, the chemistry data from five aquifer systems utilised for water supply were included into the study. Fluoride concentrations in tap water, to a great extent, ranged from 0.01 to 6.95 mg/l. Drinking water in southern Estonia, where terrigenous Middle-Devonian aquifer system is exploited, has a fluoride concentration lower than recommended level (0.5 mg/l), thus promoting susceptibility to dental caries. The western part of the country is supplied by water with excess fluoride content (1.5–6.9 mg/l). Groundwater abstracted for drinking purposes originates from Ordovician and Silurian carbonate rocks. The content of fluoride in Silurian–Ordovician aquifer system is associated with the groundwater abstraction depth and the main controlling factors of dissolved fluoride are the pH value and the chemical type of water.     

An overview on source rocks and the petroleum system of the central Upper Rhine Graben

International Journal of Earth Sciences - The petroleum system of the Upper Rhine Graben (URG) comprises multiple reservoir rocks and four major oil families, which are represented by four distinct...     

Depth matters: Microbial eukaryote diversity and community structure in the eastern North Pacific revealed through environmental gene libraries

Protistan community structure was examined from 6 depths (1.5, 20, 42, 150, 500, 880 m) at a coastal ocean site in the San Pedro Channel, California. A total of 856 partial length 18S rDNA protistan sequences from the six clone libraries were analyzed to characterize diversity present at each depth. The sequences were grouped into a total of 259 Operational Taxonomic Units (OTUs) that were inferred using an automated OTU calling program that formed OTUs with approximately species-level distinction (95% sequence similarity). Most OTUs (194 out of 259) were observed at only one specific depth, and only two were present in clone libraries from all depths. OTUs were obtained from 21 major protistan taxonomic groups determined by their closest BLAST matches to identified protists in the NCBI database. Approximately 74% of the detected OTUs belonged to the Chromalveolates, with Group II alveolates making up the largest single group. Protistan assemblages at euphotic depths (1.5, 20 and 42 m) were characterized by the presence of clades that contained phototrophic species (stramenopiles, chlorophytes and haptophytes) as well as consumers (especially ciliates). Assemblages in the lower water column (150, 500 and 800 m) were distinct from communities at shallow depths because of strong contributions from taxa belonging to euglenozoans, acantharians, polycystines and Taxopodida (Sticholonche spp. and close relatives). Species richness (Chao I estimate) and diversity (Shannon index) were highest within the euphotic zone and at 150 m, and lowest for protistan assemblages located in the oxygen minimum zone (500 and 880 m). Multivariate analyses (Bray-Curtis coefficient) confirmed that protistan assemblage composition differed significantly when samples were grouped into shallow (≤150 m) and deep water assemblages (≥150 m).     

Periodic Appearance of Coronal Holes and the Related Variation of Solar Wind Parameters

We compared the variability of coronal hole (CH) areas (determined from daily GOES/SXI images) with solar wind (daily ACE data) and geomagnetic parameters for the time span 25 January 2005 until 11 September 2005 (late declining phase of solar cycle 23). Applying wavelet spectral analysis, a clear 9-day period is found in the CH time series. The GOES/SXI image sequence suggests that this periodic variation is caused by a mutual triangular distribution of CHs ∼120° apart in longitude. From solar wind parameters a 9-day periodicity was obtained as well, simultaneously with the 9-day period in the CH area time series. These findings provide strong evidence that the 9-day period in solar wind parameters, showing up as higher harmonic of the solar rotation frequency, is caused by the “periodic” longitudinal distribution of CHs on the Sun recurring for several solar rotations. The shape of the wavelet spectrum from the Dst index matches only weakly with that from the CH areas and is more similar to the wavelet spectrum of the solar wind magnetic field magnitude. The distinct 9-day period does not show up in sunspot group areas which gives further evidence that the solar wind modulation is strongly related to CH areas but not to active region complexes. The wavelet power spectra for the whole ACE data range (∼1998 – 2006) suggest that the 9-day period is not a singular phenomenon occurring only during a specific time range close to solar minimum but is occasionally also present during the maximum and decay phase of solar cycle 23. The main periods correspond to the solar rotation (27^d) as well as to the second (13.5^d) and third (9^d) harmonic. Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users.     

Im Blick zurück ein Schritt nach vorn: ein Beitrag zum Verhältnis von Limnologie und Geschichte

Most scientists tend to ignore the history of their own discipline, at best it occurs as a sort of ‘big names history’. History is thought to be useless or at least irrelevant for the own scientific work. In the following it is questioned, whether this is an indispensable assumption of productive and progressive science. Some propositions will be discussed, what a positive historical perspective could mean for the current limnological research. It is claimed that it could be not only interesting but even exciting for limnologists to deal with their own history. One important argument is that limnology not only has a history but also is history: the ‘discovery’ of new methods, theories, concepts and instruments depends on the forgoing. Consequently, scientific progress is related to the history and progress of a particular discipline. This means in same time that the historical reflection could be an important issue to a more complete ‘explanation’ and understanding of this progress.Another reason to overcome the traditional separation into actual and historical knowledge and acting could be the hybrid character of ecology. In ecology, and consequently also in limnology, several elements of opposite scientific methodologies are merged together. Therefore the discussions on the saprobial system, an ecosystem ‘lake’ and the ‘microbial loop’ differ fundamentally. Turned positively it means that limnology should be skilled in handling with different systems of knowledge. This skills should be accessible by approaching the own history in a selfconcious way. Of course the internal view alone is not sufficient to write a history of the discipline, which aims to demonstrate the movement of progress, the relation between science and society as well as science and technics. Its history must be studied from the perspective and with the methods of the history and philosophy of science. In doing so there should be a common objective for historians and scientists that is the amelioration of the science ‘limnology’.