New insights into the environmental factors controlling the ground thermal regime across the Northern Hemisphere : a comparison between permafrost and non-permafrost areas

The thermal state of permafrost affects Earth surface systems and human activity in the Arctic and has implications for global climate. Improved understanding of the local-scale variability in the global ground thermal regime is required to account for its sensitivity to changing climatic and geoecological conditions. Here, we statistically related observations of mean annual ground temperature (MAGT) and active-layer thickness (ALT) to high-resolution (similar to 1 km(2)) geospatial data of climatic and local environmental conditions across the Northern Hemisphere. The aim was to characterize the relative importance of key environmental factors and the magnitude and shape of their effects on MAGT and ALT. The multivariate models fitted well to both response variables with average R-2 values being similar to 0.94 and 0.78. Corresponding predictive performances in terms of root-mean-square error were similar to 1.31 degrees C and 87 cm. Freezing (FDD) and thawing (TDD) degree days were key factors for MAGT inside and outside the permafrost domain with average effect sizes of 6.7 and 13.6 degrees C, respectively. Soil properties had marginal effects on MAGT (effect size = 0.4-0.7 degrees C). For ALT, rainfall (effect size = 181 cm) and solar radiation (161 cm) were most influential. Analysis of variable importance further underlined the dominance of climate for MAGT and highlighted the role of solar radiation for ALT. Most response shapes for MAGTPeer reviewe

New insights into the environmental factors controlling the ground thermal regime across the Northern Hemisphere: a comparison between permafrost and non-permafrost areas

The thermal state of permafrost affects Earth surface systems and human activity in the Arctic and has implications for global climate. Improved understanding of the local-scale variability in the global ground thermal regime is required to account for its sensitivity to changing climatic and geoecological conditions. Here, we statistically related observations of mean annual ground temperature (MAGT) and active-layer thickness (ALT) to high-resolution (∼1&thinsp;km2) geospatial data of climatic and local environmental conditions across the Northern Hemisphere. The aim was to characterize the relative importance of key environmental factors and the magnitude and shape of their effects on MAGT and ALT. The multivariate models fitted well to both response variables with average R2 values being ∼0.94 and 0.78. Corresponding predictive performances in terms of root-mean-square error were ∼1.31&thinsp;∘C and 87&thinsp;cm. Freezing (FDD) and thawing (TDD) degree days were key factors for MAGT inside and outside the permafrost domain with average effect sizes of 6.7 and 13.6&thinsp;∘C, respectively. Soil properties had marginal effects on MAGT (effect size =0.4–0.7&thinsp;∘C). For ALT, rainfall (effect size =181&thinsp;cm) and solar radiation (161&thinsp;cm) were most influential. Analysis of variable importance further underlined the dominance of climate for MAGT and highlighted the role of solar radiation for ALT. Most response shapes for MAGT ≤0&thinsp;∘C and ALT were non-linear and indicated thresholds for covariation. Most importantly, permafrost temperatures had a more complex relationship with air temperatures than non-frozen ground. Moreover, the observed warming effect of rainfall on MAGT≤0∘C reverted after reaching an optimum at ∼250&thinsp;mm, and that of snowfall started to level off at ∼300–400&thinsp;mm. It is suggested that the factors of large global variation (i.e. climate) suppressed the effects of local-scale factors (i.e. soil properties and vegetation) owing to the extensive study area and limited representation of soil organic matter. Our new insights into the factors affecting the ground thermal regime at a 1&thinsp;km scale should improve future hemispheric-scale studies.</p

Interferometric Observations of the Nuclear Region of Arp220 at Submillimeter Wavelengths

We report the first submillimeter interferometric observations of an ultraluminous infrared galaxy. We observed Arp220 in the CO J=3-2 line and 342GHz continuum with the single baseline CSO-JCMT interferometer consisting of the Caltech Submillimeter Observatory (CSO) and the James Clerk Maxwell Telescope (JCMT). Models were fit to the measured visibilities to constrain the structure of the source. The morphologies of the CO J=3-2 line and 342GHz continuum emission are similar to those seen in published maps at 230 and 110GHz. We clearly detect a binary source separated by about 1 arcsec in the east-west direction in the 342GHz continuum. The CO J=3-2 visibility amplitudes, however, indicate a more complicated structure, with evidence for a compact binary at some velocities and rather more extended structure at others. Less than 30% of the total CO J=3-2 emission is detected by the interferometer, which implies the presence of significant quantities of extended gas. We also obtained single-dish CO J=2-1, CO J=3-2 and HCN J=4-3 spectra. The HCN J=4-3 spectrum, unlike the CO spectra, is dominated by a single redshifted peak. The HCN J=4-3/CO J=3-2, HCN J=4-3/HCN J=1-0 and CO J=3-2/2-1 line ratios are larger in the redshifted (eastern) source, which suggests that the two sources may have different physical conditions. This result might be explained by the presence of an intense starburst that has begun to deplete or disperse the densest gas in the western source, while the eastern source harbors undispersed high density gas.Comment: 17 pages, 9 figures, 4 Tables. accepted by Ap

Environmental Controls of InSAR-Based Periglacial Ground Dynamics in a Sub-Arctic Landscape

Periglacial environments are characterized by highly dynamic landscapes. Freezing and thawing lead to ground movement, associated with cryoturbation and solifluction. These processes are sensitive to climate change and variably distributed depending on multiple environmental factors. In this study, we used multi-geometry Sentinel-1 Synthetic Aperture Radar Interferometry (InSAR) to investigate the spatial distribution of the mean annual ground velocity in a mountainous landscape in Northern Norway. Statistical modeling was employed to examine how periglacial ground velocity is related to environmental variables characterizing the diverse climatic, geomorphic, hydrological and biological conditions within a 148 km(2) study area. Two-dimensional (2D) InSAR results document mean annual ground velocity up to 15 mm/yr. Vertical and horizontal velocity components in the East-West plane show variable spatial distribution, which can be explained by the characteristics of cryoturbation and solifluction operating differently over flat and sloping terrain. Statistical modeling shows that slope angle and mean annual air temperature variables are the most important environmental factors explaining the distribution of the horizontal and vertical components, respectively. Vegetation and snow cover also have a local influence, interpreted as indicators of the ground material and moisture conditions. The results show contrasted model performance depending on the velocity component used as a response variable. In general, our study highlights the potential of integrating radar remote sensing and statistical modeling to investigate mountainous regions and better understand the relations between environmental factors, periglacial processes and ground dynamics.Peer reviewe

Kolmannes ensihoitajien konsultaatioista jää lääkäreiltä kirjaamatta

Ensihoitajien konsultaatioita jäi Varsinais-Suomessa kirjaamatta etenkin erikoisalapäivystäjiltä paljon. Kirjaus on tärkeä oikeusturvankin kannalta, sillä näissä konsultaatiossa vastuu siirtyy vastauksen antaneelle lääkärille

Airborne measurements of nucleation mode particles I: coastal nucleation and growth rates

International audienceA light aircraft was equipped with a bank of Condensation Particle Counters (CPCs) (50% cut from 3?5.4?9.6 nm) and a nano-Scanning Mobility Particle Sizer (nSMPS) and deployed along the west coast of Ireland, in the vicinity of Mace Head. The objective of the exercise was to provide high resolution micro-physical measurements of the coastal nucleation mode in order to map the spatial extent of new particle production regions and to evaluate the evolution, and associated growth rates of the coastal nucleation-mode aerosol plume. Results indicate that coastal new particle production is occurring over most areas along the land-sea interface with peak concentrations at the coastal plume-head in excess of 106 cm?3. Pseudo-Lagrangian studies of the coastal plume evolution illustrated significant growth of new particles to sizes in excess of 8 nm approximately 10 km downwind of the source region. Close to the plume head (?1, decreasing gradually to 53?72 nm h?1 at 3 km. Further along the plume, at distances up to 10 km, the growth rates are calculated to be 17?32 nm h?1. Growth rates of this magnitude suggest that after a couple of hours, coastal nucleation mode particles can reach significant sizes where they can contribution to the regional aerosol loading

Size distributions, sources and source areas of water-soluble organic carbon in urban background air

International audienceThis paper represents the results of one year long measurement period of the size distributions of water-soluble organic carbon (WSOC), inorganic ions and gravimetric mass of particulate matter. Measurements were done at an urban background station (SMEAR III) by using a micro-orifice uniform deposit impactor (MOUDI). The site is located in northern European boreal region in Helsinki, Finland. The WSOC size distribution measurements were completed with the chemical analysis of inorganic ions, organic carbon (OC) and monosaccharide anhydrides from the filter samples. During the measurements gravimetric mass in the MOUDI collections varied between 3.4 and 55.0 ?g m?3 and the WSOC concentration was between 0.3 and 7.4 ?g m?3. On average, water-soluble particulate organic matter (WSPOM, WSOC multiplied by 1.6) comprised 25±7.7% and 7.5±3.4% of aerosol PM1 mass and the PM1?10 mass, respectively. Inorganic ions contributed 33±12% and 28±19% of the analyzed PM1 and PM1?10 aerosol mass. Five different aerosol categories corresponding to different sources or source areas were identified (long-range transport aerosols, biomass burning aerosols from wild land fires and from small-scale wood combustion, aerosols originating from marine areas and from the clean arctic areas). Clear differences in WSOC concentrations and size distributions originating from different sources or source areas were observed, although there are also many other factors which might affect the results. E.g. the local conditions and sources of volatile organic compounds (VOCs) and aerosols as well as various transformation processes are likely to have an impact on the measured aerosol composition. Using the source categories, it was identified that especially the oxidation products of biogenic VOCs in summer had a clear effect on WSOC concentrations

Antidepressant treatment among social workers, human service professionals, and non-human service professionals : A multi-cohort study in Finland, Sweden and Denmark

Background: Social workers have an elevated risk for mental disorders, but little is known about their antidepressant treatment. Aims: To examine any and long-term antidepressant treatment among social workers in Finland, Sweden and Denmark. Methods: We linked records from drug prescription registers to three prospective cohorts: the Finnish Public Sector study, years 2006-2011, and nation-wide cohorts in Sweden and Denmark, years 2006-2014, including a total of 1.5 million employees in (1) social work, (2) other social and health care professions, (3) education and (4) office work. We used Cox proportional hazards models to estimate hazard ratios for any and long-term (>6 months) antidepressant treatment among social workers compared to the three reference occupational groups and carried out meta-analyses. Results: During follow-up, 25% of social workers had any prescriptions for antidepressants (19-24% reference occupations) and 20% for long-term treatment (14-19% reference occupations). The pooled effects for any and long-term treatment showed that probabilities were 10% higher in social workers compared to other health and social care professionals and 30% higher compared to education and non-human service professionals. Probabilities for any treatment in the three countries were relatively similar, but for long-term treatment social workers in Finland had a greater risk compared with other human service professions. Limitations: There were differences between the cohorts in the availability of data. Specific diagnoses for the antidepressant treatment were not known neither adherence to treatment. Conclusion: Social workers have a higher risk for any and long-term antidepressant treatment than other human and non-human service professionals.Peer reviewe

Climate mediates continental scale patterns of stream microbial functional diversity

Background Understanding the large-scale patterns of microbial functional diversity is essential for anticipating climate change impacts on ecosystems worldwide. However, studies of functional biogeography remain scarce for microorganisms, especially in freshwater ecosystems. Here we study 15,289 functional genes of stream biofilm microbes along three elevational gradients in Norway, Spain and China. Results We find that alpha diversity declines towards high elevations and assemblage composition shows increasing turnover with greater elevational distances. These elevational patterns are highly consistent across mountains, kingdoms and functional categories and exhibit the strongest trends in China due to its largest environmental gradients. Across mountains, functional gene assemblages differ in alpha diversity and composition between the mountains in Europe and Asia. Climate, such as mean temperature of the warmest quarter or mean precipitation of the coldest quarter, is the best predictor of alpha diversity and assemblage composition at both mountain and continental scales, with local non-climatic predictors gaining more importance at mountain scale. Under future climate, we project substantial variations in alpha diversity and assemblage composition across the Eurasian river network, primarily occurring in northern and central regions, respectively. Conclusions We conclude that climate controls microbial functional gene diversity in streams at large spatial scales; therefore, the underlying ecosystem processes are highly sensitive to climate variations, especially at high latitudes. This biogeographical framework for microbial functional diversity serves as a baseline to anticipate ecosystem responses and biogeochemical feedback to ongoing climate change.Peer reviewe