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This paper describes the development of an Airborne Wind Vector Scatterometer for low-resolution wind speed measurements. The scatterometer is designed to meet a wind speed accuracy requirement of 1 m/s. In this ad hoc and low-budget project, the development of the instrument exploited some already existing subsystems. The development started from the definition of the scientific system requirements and ended with two experimental flights for wind vector retrieval from three test areas in the Gulf of Finland, the Baltic Sea. One of the flights was planned for a simultaneous overpass with the TDS-1 satellite that was conducting Global Navigations Satellite System – Reflectometry (GNSS-R) measurements. The results confirm the measurement capabilities of the GNSS-R technology and the desired 1 m/s wind speed accuracy of the scatterometer that was developed.

Reconstructed variations in stratigraphic thicknesses combined with mapped variations in fold-and-thrust belt structural styles and patterns of the entire Palaeoproterozoic Perapohja Belt in northern Finland show that both the deposition of the 2.4–1.9 Ga supracrustal rocks and the structural evolution during the subsequent Svecofennian Orogeny (1.9–1.8 Ga) have been tightly controlled by (i) the palaeo-topography of the Archaean (>2.5 Ga) basement, and (ii) the reactivation of Archaean basement faults during the multiple stages of rifting and deposition of the supracrustals, as well as during subsequent basin inversion and fold-and-thrust belt development. Folds and thrusts in the supracrustal sequence are found to be largely detached from the underlying basement along the Petajaskoski Detachment Zone (PDZ) that formed within a mechanically weak stratigraphic unit in the basal part of the Perapohja Belt stratigraphy. The pattern of contractional structures is complex, but developed during one phase of simple, progressive south-vergent thrusting. Two styles of basement-cover linkage are recognised: The hard-linked style is best illustrated by the reverse Sihtuuna Fault currently defining the northern margin of the E-W to ENE-WSW trending basement horsts and the overlying anticlines, and juxtaposing the stratigraphically lowermost Perapohja Belt rocks with higher-up stratigraphy, indicating the fault is inherited after a pre-existing basement structure. Based on the distribution and thickness variation of the Palaeoproterozoic supracrustal units, the faults bounding the basement horst were active as extensional faults during deposition. The soft-linked style relationship is evident as abrupt terminations of thrust-related elongate domes and localisation of the compressional overprint into the NW-SE trending central graben. Understanding the basement architecture and basement-cover linkages is highly significant because the majority of the known mineralizations of the belt are located along or close to the basement faults.

National Forest Inventories (NFI) are key data and tools to better understand the role of forests in the global carbon budget. Traditionally inventories have been carried out as field work, which makes them laborious and expensive. In recent years, the development of various remote sensing techniques to improve the cost-efficiency of the NFIs has accelerated. The goal of this study is to determine the usability of open and free multitemporal multispectral satellite images from the European Space Agency's Sentinel-2 satellite constellation and to compare their usability in forest inventories against airborne laserscanning (ALS) and three-dimensional data obtained with high-resolution optical satellite images from WorldView-2 and Synthetic Aperture Radar (SAR) stereo data from TerraSAR-X. Ground reference consisted of field data collected over 74 boreal forest plots in Southern Finland in 2014 and 2016. Features utilizing both single- and multiple-date information were designed and tested for Sentinel-2 data. Due to high cloud cover, only four Sentinel-2 images were available for the multitemporal feature analysis of all reference plots within the monitoring window. Random Forest technique was used to find the best descriptive feature sets to model five forest inventory parameters (mean height, mean diameter at breast height, basal area, volume, above-ground biomass) from all input remote sensing data. The results confirmed that the higher spatial resolution input data correlated with more accurate forest inventory parameter predictions, which is in line with other results presented in literature. The addition of temporal information to the Sentinel-2 results showed limited variation in prediction accuracy between the single and multidate cases ranging from 0.45 to 1.5 percentage points, whereof mean height, basal area and aboveground biomass are lower for single date with relative RMSEs of 14.07%, 20.66% and 24.71% respectively. Diameter at breast height and volume are lower for multi date feature combination withrelative RMSEs of 18.38% and 27.21%. The results emphasize the importance of obtaining more evenly distributed data acquisitions over the growing season to fully exploit the potential of temporal features.

Recent years have witnessed the practical value of open-access Earth observation data catalogues and software in land and forest mapping. Combined with cloud-based computing resources, and data collection through the crowd, these solutions have substantially improved possibilities for monitoring changes in land resources, especially in areas with difficult accessibility and data scarcity. In this study, we developed and tested a participatory mapping methodology utilizing the open data catalogues and cloud computing capacity to map the previously unknown extent and species composition of forest plantations in the Southern Highlands area of Tanzania, a region experiencing a rapid growth of smallholder-owned woodlots. A large set of reference data, focusing on forest plantation coverage, species and age information distribution, was collected in a two-week participatory GIS campaign where 22 Tanzanian experts interpreted very high-resolution satellite images in Google Earth with the Open Foris Collect Earth tool developed by the Food and Agriculture Organization of the United Nations. The collected samples were used as training data to classify a multi-sensor image stack of Landsat 8 (2013–2015), Sentinel-2 (2015–2016), Sentinel-1 (2015), and SRTM derived elevation and slope data layers into a 30 m resolution forest plantation map in Google Earth Engine. The results show that the forest plantation area was estimated with high overall accuracy (85%). The interpretation accuracy of local experts was high considering general definition of forest plantation declining with increased details in interpretation attributes. The results showcase the unique value of local expert participation, enabling the collection of thousands of reference samples over a large geographical area in a short period of time simultaneously building the capacity of the experts. However, sufficient training prior to the data collection is crucial for the interpretation success especially when detailed interpretation is conducted in complex landscapes. Since the methodology is built on open-access data and software, it presents a highly feasible solution for repetitive land resource mapping applicable at different spatial scales globally.

To rapidly produce oil, downhole heating technology requires an electric heater, which is limited by the diameter of the heat injection well, with long-term working stability and high-efficiency heat transfer. Simulations indicated that heater with continuous helical baffles is more suitable for downhole heating technology than heater with segmental baffles in terms of long-term working stability. Then, experiments were conducted on four continuous helical schemes with pitches of 50, 110, 160, and 210 mm. The test results showed that, in the test scope, the heater with the helical pitch of 110 mm (H110) had the best comprehensive performance, which was 2.95–3.75 times better than that of the heater with the helical pitch of 210 mm (H210). Under the same working conditions, heaters with smaller helical pitch values produce less irreversibility in the heat transfer process. In addition, the heaters with helical pitch values of 110, 160, and 210 mm were more effective at a lower Reynolds number, whereas the heater with the helical pitch of 50 mm could be used under a wide effective range of Reynolds numbers. The conclusions are benefit to setting the heating parameters of electric heater during the process of oil shale in-situ pyrolysis.

A key question in aquatic elemental cycling is related to the influence of bottom water oxygen conditions in regulating the burial and release of carbon under climate warming. In this study, we used head capsules of Chironomidae larvae to assess community and diversity change between the past (estimated as Pre-Industrial Period) and present and to reconstruct changes in hypolimnetic oxygen conditions from 30 subarctic ecotonal lakes (northeastern Lapland) using the top-bottom paleolimnological approach applying surface sediment (topmost 0-2 cm) and reference (4-5 cm) samples. Subsequently, we tested the findings against dissolved organic carbon (DOC) concentration of the sites. We found that the benthic communities were statistically dissimilar between the past and the present with largest changes occurring in the more transparent oligo-mesohumic lakes. However, murky polyhumic lakes displayed uniformly a decrease in diversity. The chironomid-inferred oxygen values showed a general decrease toward the present with largest shifts in low-DOC lakes, whereas no significant changes were found in the hypolimnetic oxygen conditions of high-DOC lakes, which were often located in wet-land areas. These finding suggest that lakes associated with constant organic carbon inputs are more resilient toward climate-induced reductions in hypolimnetic oxygen. (c) 2018 Elsevier B.V. All rights reserved.

The article shows Generalized Interpolation Material Point Method numerical simulation of the Sainte Monique landslide. The simulation uses a strain-rate dependent Tresca constitutive model, extended with strain softening behaviour for structured clays. First, the paper replicates fall cone tests to validate the constitutive model and to select the material parameters. Afterwards, the paper shows the Sainte Monique landslide simulation which additionally considers shear band thickness to reduce the mesh-dependence. The results suggest that the strain-rate affects the prediction of the run-out distances and leads to the landslide acceleration-deceleration cycles (reported in, e.g. Corominas et al., 2005; Wang et al., 2010).

Forest soils represent a large carbon pool and already small changes in this pool may have an important effect on the global carbon cycle. To predict the future development of the soil organic carbon (SOC) pool, well-validated models are needed. We applied the litter and soil carbon model Yasso15 to 1838 plots of the German national forest soil inventory (NFSI) for the period between 1985 and 2014 to enables a direct comparison to the NFSI measurements. In addition, to provide data for the German Greenhouse Gas Inventory, we simulated the development of SOC with Yasso15 applying a climate projection based on the RCP8.5 scenario. The initial model-calculated SOC stocks were adjusted to the measured ones in the NFSI. On average, there were no significant differences between the simulated SOC changes (0.25 ± 0.10 Mg C ha−1 a−1) and the NFSI data (0.39 ± 0.11 Mg C ha−1 a−1). Comparing regional soil-unit-specific aggregates of the SOC changes, the correlation between both methods was significant (r2 = 0.49) although the NFSI values had a wider range and more negative values. In the majority of forest types, representing 75% of plots, both methods produced similar estimates of the SOC balance. Opposite trends were found in mountainous coniferous forests on acidic soils. These soils had lost carbon according to the NFSI (−0.89 ± 0.30 Mg C ha−1 a−1) whereas they had gained it according to Yasso15 (0.21 ± 0.10 Mg C ha−1 a−1). In oligotrophic pine forests, the NFSI indicated high SOC gains (1.36 ± 0.17 Mg C ha−1 a−1) and Yasso15 much smaller (0.29 ± 0.10 Mg C ha−1 a−1). According to our results, German forest soils are a large carbon sink. The application of the Yasso15 model supports the results of the NFSI. The sink strength differs between forest types possibly because of differences in organic matter stabilisation.

Vegetation plays an important role in the climate system. The extent to which vegetation impacts climate through its structure and function varies across space and time, and it is also affected by land cover changes. In areas with both multiple growing periods and significant land cover changes, such as the Horn of Africa, identifying vegetation influence on land surface temperature (LST) through radiative changes needs further investigation. In this study, we used a 13-year time series (2001 - 2013) of remotely sensed environmental data to estimate the contribution of radiative mechanism to LST change due to growing season albedo dynamics and land cover conversion. Our results revealed that in taller woody vegetation (forest and savanna), albedo increases during the growing period by up to 0.04 compared with the non-growing period, while it decreases in shorter vegetation (grassland and shrubland) by up to 0.03. The warming impact due to a decrease in albedo during the growing period in shorter vegetation iscounteracted by a considerable increase in evapotranspiration, leading to net cooling. Analysis of land cover change impact on albedo showed a regional annual average instantaneous surface radiative forcing of -0.03 +/- 0.02 W m(-2). The land cover transitions from forest to cropland, and savanna to grassland, displayed the largest mean albedo increase across all seasons, causing an average instantaneous surface radiative forcing of -2.6 W m(-2) and -1.5 W m(-2) and a decrease in mean LST of 0.12 K and 0.09 K, all in dry period (December, January, February), respectively. Despite the albedo cooling effect in these conversions, an average net warming of 1.3 K and 0.23 K was observed under the dominant influence of non-radiative mechanisms. These results show that the impact of radiative mechanism was small, highlighting the importance of non-radiative processes in understanding the climatic impacts of land cover changes, as well as in delineating effective mitigation strategies.

Digital 3D geometric models have become a central tool for geo-information. For many participatory and collaborative applications, distributing these models easily is essential. Several technical solutions exist for creating online systems that facilitate the study of 3D models in the context of the built environment. To provide an overview on browser based interactive 3D visualizations, we present a set of existing systems applied in Finland, and discuss their common properties and differences. To obtain first-hand experience, we experiment with an online 3D application development platform. The systems studied show a high potential for browser based 3D applications: interactive visualizations with multi-user characteristics and dynamic elements can be built by leveraging the 3D web technologies. Finally, we suggest a framework for discussing browser based 3D systems, covering the spectrum of possibilities available in modern web-based 3D for built environment applications.

This article discusses how a temporary gathering of researchers in the remote and peripheral Ny-Alesund research station (78°55’N, 11°54’E) affected the rhythms of knowledge creation in an internat...

Historical sea ice core chlorophyll-a (Chla) data are used to describe the seasonal, regional, and vertical distribution of ice algal biomass in Antarctic landfast sea ice. The analyses are based on the Antarctic Fast Ice Algae Chlorophyll-a data set, a compilation of currently available sea ice Chla data from landfast sea ice cores collected at circum-Antarctic nearshore locations between 1970 and 2015. Ice cores were typically sampled from thermodynamically grown first-year ice and have thin snow depths (mean = 0.052 ± 0.097 m). The data set comprises 888 ice cores, including 404 full vertical profile cores. Integrated ice algal Chla biomass (range, SCOPUS: ar.j, info:eu-repo/semantics/published

Operation of a small CubeSat in the deep-space microgravity environment brings additional challenging factors including the increased radiation environment, the significant contribution of non-gravitational forces to the satellite orbit, or the limited communication opportunities. These factors need to be taken into account in the form of modifications to the classic CubeSat architecture. Increased radiation resistance, the semi-autonomous satellite operation, navigation, and the active orbit correction are required. Such a modified CubeSat platform can potentially deliver a high performance to mass and cost ratios. The Asteroid Spectral Imaging Mission (ASPECT) is a three unit (3U) CubeSat mission built on these principles. It is part of the AIDA (Asteroid Impact & Deflection Assessment) project to the binary asteroid Didymos. ASPECT is equipped with a visible to near-infrared hyperspectral imager and will deliver both technological knowledge as well as scientific data about the origin and evolution of Solar System small bodies.

Bed siltation can drastically alter the physical conditions of headwater streams and is therefore a stressor for stream ecosystems. We studied 32 headwater streams that represented near‐natural (reference; N = 11), sediment‐impacted (N = 12), or wood‐ (N = 4) or stone‐restored (N = 5) streams to quantify how extensive siltation and restoration with either large woody debris (LWD) or boulder structures influence transient storage conditions. We carried out repeated stream tracer experiments, field measurements of habitat characteristics, and numerical simulations to determine the effects of siltation and restoration on total transient storage. Compared with reference streams, impacted streams had a smaller storage zone cross‐sectional area (Aₛ/A) ratio and fraction of median travel time due to transient storage (F₂₀₀), whereas restored streams had transient storage conditions similar to near‐natural conditions. Both of the two restoration methods had positive but differing impacts on bed sediment and transient storage properties. The LWD restoration created diverse total transient storage conditions, whereas boulder restoration decreased fine sediment cover. Addition of both LWD and boulders could thus aid the recovery of headwater streams from excessive sediment input and increase transient storage and in‐stream habitat complexity.

Rapid magnetic fluctuations are known to be closely linked to the high-latitude geomagnetic activity, in particular, to geomagnetic pulsations and subtorms. Increasing amount of commercial activity in the arctic regions requires better monitoring capability and improved understanding on the effects of geomagnetic hazards to infrastructure. In this study, we analyze rapid, 1-s fluctuations in Greenland. To measure high-frequency geomagnetic fluctuations in the auroral oval and polar cap, we use high time resolution data of 1 s from 12 stations covering a large latitudinal range of 64 to 84 quasi-dipole geomagnetic latitude (QDGMlat). We found out that the large magnetic field fluctuations exceeding 0.2 nT/s are observed 10–30% of the time in auroral oval latitudes, depending on the solar cycle phase and station location. The latitudinal differences are much larger in fluctuation coverage (fractional derivative rate, FDR) than in fluctuations amplitude (dH/dt). The highest |dH/dt| and FDRs at noon are observed at the northern stations from 72 to 84 QDGMlat, while in south Greenland from 72 to 65 QDGMlat, the highest |dH/dt| and FDRs are recorded at midnight. The largest differences in seasonal variation between noon and midnight are observed in the polar cap, where a summer increase is seen at noon and almost flat seasonal profile at midnight.

This study contributes to the scholarly call to increase studies on migration from the perspective of postcolonial thought by exploring a novel ethnographic case; the migration of Tibetans who have...

Frazil and anchor ice cause blockage of water intakes and icing of other type of submerged objects. In this paper, the physical mechanisms that control these phenomena are discussed and analyzed. Our conclusions are somewhat different from the views presented earlier. 1) Ice crystals in water may originate from microbubbles and turbulence, so that nucleation may occur regardless of an external source 2) The number concentration of ice crystals may not necessarily increase much during an active frazil ice event, 3) The heat transfer from a frazil ice crystal is controlled by its relative rise velocity, not by water turbulence, 4) The collision efficiency of frazil ice crystals on grid components is so small that frazil typically causes no blockage of submerged water intakes, and 5) Blockage is largely caused by ice platelets that grow in-situ on the structural components. We model frazil and anchor ice formation theoretically and find that the uncertainty about the concentration of ice crystals is the main obstacle to accurate modelling. Within these limits, our model results agree well with the available experimental data.

Marine dissolved organic carbon (DOC) is formed of a large number of highly diverse molecules. Depending on the environmental conditions, a fraction of these molecules may become progressively resistant to bacterial degradation and accumulate in the ocean for extended time scales. This long-lived DOC (the so-called recalcitrant DOC, RDOC) is thought to play an important role in the global carbon cycle by sequestering carbon into the ocean interior and potentially affecting the climate. Despite this, RDOC formation is underrepresented in climate models. Here we propose a model formulation descripting DOC recalcitrance through two state variables: one representing the bulk DOC concentration and the other representing its degradability (k) which varies depending on the balance between the production of “new” DOC (assumed to be easily degradable) and bacterial DOC utilization assumed to leave behind more recalcitrant DOC. We propose this formulation as a means to include RDOC dynamics into climate model simulations.

We developed a methodology to evaluate quantitative uncertainty characteristics of satellite data retrievals including the contribution of systematic error and statistical error. This is introduced by assessing the total product error of optical, satellite data-based, Fractional Snow Cover (FSC) estimates. Here the FSC estimation is based on an algorithm allowing the consideration of the effect of different error sources; a semi-empirical reflectance model describing the relationship of the observed reflectance and FSC through several variables and parameters. We assume that after the statistical error analysis, the remaining portion of total product error arises due to systematic factors. Hence, first we define a statistical error component through the theory of error propagation, and then estimate the total product error (PE) by using in situ observations on FSC, and finally derive the systematic error from these two error components. The experimental approach for estimating PE is conducted through an analysis of the observed estimation errors (i.e. residuals) in the GlobSnow Snow Extent (SE) v2.1 products on FSC. In practice, independent in situ snow course observations from Finland on FSC are compared to corresponding satellite FSC estimates to quantify the residuals. The approach is then illustrated for an extended region of corresponding European boreal forest. Our results show that the total PE in the GlobSnow FSC product is significantly higher than the originally provided statistical error. This is due to deficiencies in the parameterization of the applied forward modelling approach, in particular in the consideration of the forest canopy effects.

Earth Observation (EO) offers spatially and temporally unique data for generating information required under various environmental regulations for assessing the status of surface waters. These requirements, which are laid down in, for example, European Union directives and the Clean Water Act in the United States, share two core elements with respect to status assessments: 1) the status assessment is done using discrete classes, typically for water bodies, sub-areas or critical sites representative for certain area of interest, and 2) phytoplankton chlorophyll a (chl-a) is one of the main variables considered. We analysed the benefits of using chl-a concentrations derived from EO data for the status assessments specified in the EU Water Framework Directive (WFD). Our study focused especially on EO observations' ability to capture extreme and transient events (such as instances of cyanobacteria blooms) more frequently than the monitoring-station data conventionally employs. The accuracy of EO-based chl-a assessment was studied for, in all, 129 Finnish water bodies in the area of the Baltic Sea, in Northern Europe. Natural conditions in this coastal area – particularly its multitude of small bays, numerous estuaries, and mosaic of islands – impose exceptionally strict requirements for an EO instrument's spatial resolution. The analysis revealed that an instrument with a 300 m resolution, such as the MEdium Resolution Imaging Spectrometer (MERIS) or Ocean and Land Colour Instrument (OLCI), can be used to estimate the water quality in 62% of these water bodies. Processing of MERIS data into chl-a concentrations by means of a FUB inversion model demonstrated good accuracy relative to monitoring stations' measurements for the open-water season in 2003–2011. This extensive dataset showed a 23% difference in modal values between EO- and station-sampling-based chl-a concentrations. The bias in EO chl-a estimates was found to increase with low Secchi disk depth, elevated turbidity, and the presence of intensive phytoplankton blooms. The monitoring-station and EO data showed similar distributions of chl-a observations for a given day and location, a finding that supports the comprehensive use of EO-derived chl-a concentrations in assessment. For determination of a water body's status, the EO data required but also allowed for statistical analysis that differs from what has typically been utilised with sparse measurements from monitoring-station data. The geometric mean or the mode of the EO observations was found to represent the main bulk of the chl-a concentrations well statistically. In contrast, the arithmetic mean of EO observations yields chl-a concentrations that are roughly 1.1–1.6 μg/l higher and hence can lead to over-estimation in the associated status assessment. This paper also presents a new approach applicable for evaluating the validity of EO-based algorithms for any coastal water area requiring assessment. With this quality-grade (QG) method, the EO chl-a estimation accuracy is rated in terms of three grades, with water bodies taken as the evaluation units. For this, the method utilises statistical differences between EO and station-sampling chl-a concentrations and applies background information on optical properties obtained from measurements at routine-monitoring stations. The QG method showed the EO-based chl-a accuracy to suffice for assessing the status of 65% of the coastal water bodies examined. At concentrations representing the threshold for the target of “good status” under the WFD, the EO approach produced 0.6 μg/l higher chl-a values than the stations' sampling did. The MERIS results point to clear benefits of using OLCI-based status assessment throughout the Sentinel-3 era.

The stable isotopic composition of chitinous remains of Cladocera (water fleas) and freshwater Bryozoa (moss animals) preserved in lake sediment records can provide supporting insights into past environmental and ecosystem changes in lakes. Here we explore whether analyses of these remains isolated from lake flotsam can provide information on the driving variables affecting the isotopic composition of these remains. We collected flotsam in 53 lakes and found enough material in 33 lakes to measure the stable carbon and nitrogen isotope ratios (expressed as δ13C and δ15N values, respectively) of resting stages. These values were compared with lake characteristics, water chemistry measurements, and the isotopic composition of sedimentary organic matter (SOM) in the lakes. Mean δ13C values of cladoceran ephippia and SOM were correlated and both were also negatively correlated with deep water methane concentrations and indicators of lake stratification. This supports the findings of previous studies that methane-derived carbon can provide a significant proportion of carbon entering planktonic food webs. Mean δ15N values of bryozoan statoblasts and SOM were correlated, suggesting that both reflect the δ15N values of phytoplankton. Our results provide information on how environmental variables in lakes can influence the δ13C and δ15N values in resting stages, but flotsam samples can also potentially be used to assess seasonal stable isotope variability of resting stages. Both types of information are important to improve palaeoenvironmental interpretations of stable isotope records based on these remains in lake sediments.

Throughout Europe and beyond, a particular focus of regeneration and infill policies is set on mature inner city and suburban neighborhoods, where properties are often owned by commonholds. The component of collective decision-making makes infill development on commonhold areas especially complex. This paper conceptualizes the role and effects of collective decision making in the context of infill development on sites owned by commonholds and explores how the advantages and disadvantages of infill development are distributed among owners. The paper has a policy contribution as it assesses the distributive justice of infill development decision from the perspective of commonhold ownership structure and its implications. The findings of this paper contribute to the governance of commonholds, especially with respect to equality of decision-making and rights of majority and minority owners. These issues are essential regarding to the growing importance of the apartment owners in the governance of built environment and related challenges, such as regeneration of already developed urban areas.

In this reflection, we seek to develop some of Professor Gill’s inspiring ideas on the notion of (un)welcome further. We do this, in particular, by problematizing his largely dualistic conception of the emotionally-invested, inter-personal forms of welcome contra a bureaucratic tendency to abstract welcome, to hollow it out emotionally. We argue that if applied too rigidly, this dichotomy can be unwieldy for making sense of the actual socio-spatial and emotional dynamics of (un)welcome. To elaborate this criticism, we expand on the notion of welcome from three interrelated perspectives. First, we argue that besides the opposite poles of people who welcome refugees, and forces that attempt to exclude them, great many actors convey more ambiguous and contextually varying attitudes to (un)welcoming immigrants. In the light of Lefebvre’s conceptual triad of social space, we next point out that Gill’s conceptualization pays inadequate heed to the practiced and societally recompensing aspects of everyday spatiality and welcoming. Finally, we take a cue from Gill’s suggestion to analyze welcome from the emotional geographies perspective, and reflect on exclusionary and inclusionary socio-spatial processes related to refugees’ emotions (lived space) and coping tactics (practiced space).

The degree of which the observable canopy bidirectional reflectance factors (BRF) express plant trait variation at leaf and canopy scales is the fundamental physical basis underlying the use of optical remote sensing data for discriminating tree species and estimating forest biophysical variables. In this study, we quantified the relative contribution of variations in leaf optical properties (LOP), canopy structural properties, and understory reflectance, to canopy BRF variability in a boreal forest, at the spatial and spectral resolutions of Sentinel-2 (S2) Multi-Spectral Instrument. Our approach was based on physically-based forest reflectance model and global sensitivity analysis (SA) parameterized entirely with field measurements. Results showed LOP had dominant contribution to canopy BRF in shortwave infrared (SWIR) in multispecies forest areas, while canopy gap fraction in sensor's view direction (i.e. nadir) was consistently found as the main driver of canopy BRF in red. This implies the satellite-measured BRF in red is the most robust predictor of effective canopy cover (ECC), while BRF in SWIR are optimal for tree species classification based on interspecific differences in mean leaf traits.

Finland is one of the northernmost countries utilizing ground source heat pumps (GSHPs). In this north European country, GSHPs’ operating conditions are characterized by the cold climate, and hard, crystalline bedrock. Environmental risks and technical problems with ground heat exchangers (GHEs) have been much discussed, but the frequency of complications has not been previously studied in Finland. This article examines the types and construction practices of GHEs, and the range of problems in GHEs experienced by the practitioners. The data was collected through a questionnaire study among Finnish GSHP practitioners, and thematic interviews of Finnish heat pump experts. Borehole heat exchangers (BHEs) proved to be the most popular GHE type in Finland with a share of 85%. The questionnaire responses indicate that the most common complications in BHEs are connected to collapsed boreholes, and artesian or otherwise abundant water yields. Also, issues relating to heat transfer fluids, drilling through multiple aquifers, and design errors are discussed.

As a result of the First World War several new nation-states emerged on the map of Europe. One of them was the Republic of Estonia, emerging from the ruins of the Russian Empire. As Estonians had never had their own state before, the establishment of the parliamentary republic, its institutions and a national identity was a big challenge for its small elite. First and foremost, the ambition was to do things differently from the previous rulers. The Estonian economic geographer Edgar Kant played an important role in the development of his country between 1920 and 1940. His geography was politically motivated, innovative and pragmatic as the rapid development of the state required new theories and methods. The methodological basis for Kant's ‘innovative geography’ became Walter Christaller's central place theory, and he was the first in the world to understand the importance of applying it in empirical research, doing so in the 1930s in the reform of Estonian rural municipalities. In September 1944, Edgar Kant fled from Estonia to Lund and Christaller's theory spread more widely through Kant's interactions with Torsten Hagerstrand in Sweden and later Edward Ullman and Brian Berry in the United States. This paper reviews the relatively unknown geography, and the complicated life, of Edgar Kant, who, it is argued, strongly influenced the trajectory of the triumph of the ‘new geography’ in the 1950s. Through this example it will be shown how peripheral actors and places can play key roles in innovation diffusion and intellectual history.

We used a 3D hydrodynamic model, COHERENS, to simulate the temperature, salinity and currents in an extremely complicated area, the Archipelago Sea in the Baltic Sea. The high-resolution model domain with approximately 460 m resolution was nested inside a coarser resolution (~ 3.7 km) grid covering the entire Baltic Sea. The verification of the model results against temperature and salinity measurements showed that the model well captured the seasonal temperature cycle in the surface layer, both in the inner and outer archipelago. In the inner archipelago, the model tended to reproduce higher temperatures in the bottom layer than were measured. The modelled vertical temperature and salinity stratifications were not as pronounced as the measured ones but did describe the overall vertical structure. There was large year-to-year variability in the annual mean surface circulation, both in direction and magnitude. In the deeper channels crossing the Archipelago Sea, there were some year-to-year differences in the magnitudes of the bottom layer currents, but there was very little difference in the directions. These differences were studied by introducing passive tracers into the model through river discharge and as point sources. The results showed that the prevailing wind conditions resulted in southward net transport from the Bothnian Sea towards the Baltic Proper. However, due to the variability in the wind conditions in some years, a significant proportion of transport can also be towards north, from the Baltic Proper to the Bothnian Sea.

Sediment microfacies, geochemical μ‐XRF and X‐ray density analyses were conducted on varved sediments from Lake Kortejärvi (eastern Finland) covering the last 2700 years. The varves comprise couplets of detrital and organic sub‐layers throughout the complete time‐span. Based on their microfacies and stratigraphical position within a varve as well as comparisons with local discharge and meteorological data, thicker detrital layers are interpreted to reflect intensified snow‐melt floods following more humid winters. Detailed comparisons with monthly to annually resolved North Atlantic Oscillation (NAO) indices back to AD 1049 (901 a BP) suggest that multidecadal increases in snow‐melt layer thickness tend to be connected with a more positive phase of the NAO and, consequently, warmer winters. In contrast, distinct centennial intervals of thicker snow‐melt layers from −40 to 170, 280 to 460 and 1900 to 2300 a BP as well as around 2600 a BP do not consistently correspond to a particular NAO phase, but coincide with extended sea‐ice margins and a colder North Atlantic climate, causing intensified and southward shifted westerly cyclones. Our results point to a differential modification of North Atlantic winter hydroclimate working on varying time scales.

Permafrost dynamics play an important role in the surface hydrology and carbon balance of northern peatlands. Plant macrofossil analysis with radiocarbon dating has been widely used in detecting pa ...

Polymetallic quartz veins, with up to 1500 ppm indium, have been discovered recently in the Sarvlaxviken area within the 1.64 Ga anorogenic multiphase Wiborg rapakivi batholith and adjacent 1.90 Ga Svecofennian crust in SE Finland. Evidence from primary fluid inclusions in the Sarvlaxviken area provides new information on the hydrothermal transport and depositional processes of metals in anorogenic granites. Fluid inclusions with variable aqueous liquid and vapour proportions (5–90 vol.% vapour) occur in quartz, cassiterite and fluorite belonging to three generations of polymetallic quartz veins. Microthermometry indicates that the veins were deposited at temperatures that range from ~500°C down to 2-F-Cl-S and metals. Fluid inclusions with low salinities dominate, but higher salinities are recorded in metal-rich parts of the veins. The turbulent fluid flow, with complex geometry and temperature-salinity patterns, may explain why sulfide and/or oxide opaque minerals occur irregularly, and are locally the dominating vein minerals, but disappear completely into barren parts of the quartz veins. All fluids are considered to have been generated by the F-rich Marviken granite (and related granite dykes), which show all geochemical criteria for an ore-fertile granite. The quartz veins investigated in the adjacent Svecofennian country rocks are considered to represent the very last stage of a fluid with similar characteristics to the fluid responsible for the ore formation in the Sarvlaxviken area, but that had cooled to

Scanning electron microscopy (SEM) is a powerful tool for observing microbe-mineral interactions in situ. Despite its wide usage in geomicrobiology there is no consensus on how the samples should be handled before visualizing in SEM. We compared response of artificial laboratory-grown bacterial community and natural in situ microbes on terrestrial basalt to different sample pre-treatment methods with the aim to preserve microbe-mineral interaction interface. Air-drying was the only method that maintained the location of loosely attached bacteria on a mineral surface, whereas chemical fixation and drying dislocated the cells. On the contrary, chemical fixation preserved the cellular morphology while air-drying caused the collapse of most of the laboratory-grown cells. Natural microbial communities on dry terrestrial basalt were composed of desiccation resistant microbes which remained attached to the surface and partially maintained their morphology regardless of the sample pre-treatment method. None of the tested methods allowed visualization of microbe-mineral interface in a biofilm. We suggest air-drying as a main sample pre-treatment method for visualizing microbes on mineral surfaces when loss of morphology is secondary to potentially dislocated cells and to potential chemical changes in the sample caused by the chemical fixation reagents.

The extremes of month-specific spatial temperature differences were studied for a first time in the high-latitude city of Lahti and its surroundings in southern Finland. During the 2-year observation period (6/14–5/16), the largest momentary temperature difference, 11.1 °C, was detected in February, and the smallest, 6.2 °C, in April. The impacts of various environmental factors during the extreme situations were estimated by site-specific analysis of the warmest and coldest observation sites and a stepwise multiple linear regression model including all the 8 observation sites. The extreme temperature differences were characterised by inversions especially in winter and spring, the warmest site being the hill-top location in Kivistönmäki. In summer the role of urban heating was more apparent, and the temperature was the highest in the relatively low-lying city centre. In autumn the heating impact of the relatively warm Lake Vesijärvi caused the largest temperature differences with harbour as the warmest site. The weather during all of the momentary extreme situations was calm and in the majority of the situations also clear. The impact of cloud cover was less critical than that of wind speed in reducing spatial temperature differences. The momentary extreme situations existed at night or at dawn, with one exception: only in January, during the cold weather period dominated by high pressure, the delayed break of inversion in the vicinity of Lake Vesijärvi caused the extreme temperature difference to exist in the afternoon, reflecting for its part the substantial stabilising impact of seasonal ice cover on Lake Vesijärvi. Keywords: Extreme temperature difference, Land use, Topography, Urban heat island, Water body, Seasonality

Collision efficiency is an important parameter for an icing prediction model. It mainly depends on wind velocity, conductor diameter and water droplet diameter. However, water droplets have a spectrum of sizes, which makes the task of calculating the overall collision efficiency time consuming. Therefore, some representative droplet sizes have been used, such as the median volume diameter. In this paper, a novel representative droplet diameter is presented for the calculation of the collision efficiency. The results are compared with those using the median volume diameter and the entire droplet size spectrum. The results show that this parameterization provides a more stable approximation than the median volume diameter when the collision efficiency changes, and is more appropriate when the collision efficiency is small. Mathematical explanation for this is given, and the limitation of this method is discussed.

Significance Identifying and explaining regional differences in tropical forest dynamics, structure, diversity, and composition are critical for anticipating region-specific responses to global environmental change. Floristic classifications are of fundamental importance for these efforts. Here we provide a global tropical forest classification that is explicitly based on community evolutionary similarity, resulting in identification of five major tropical forest regions and their relationships: (i) Indo-Pacific, (ii) Subtropical, (iii) African, (iv) American, and (v) Dry forests. African and American forests are grouped, reflecting their former western Gondwanan connection, while Indo-Pacific forests range from eastern Africa and Madagascar to Australia and the Pacific. The connection between northern-hemisphere Asian and American forests is confirmed, while Dry forests are identified as a single tropical biome., Knowledge about the biogeographic affinities of the world’s tropical forests helps to better understand regional differences in forest structure, diversity, composition, and dynamics. Such understanding will enable anticipation of region-specific responses to global environmental change. Modern phylogenies, in combination with broad coverage of species inventory data, now allow for global biogeographic analyses that take species evolutionary distance into account. Here we present a classification of the world’s tropical forests based on their phylogenetic similarity. We identify five principal floristic regions and their floristic relationships: (i) Indo-Pacific, (ii) Subtropical, (iii) African, (iv) American, and (v) Dry forests. Our results do not support the traditional neo- versus paleotropical forest division but instead separate the combined American and African forests from their Indo-Pacific counterparts. We also find indications for the existence of a global dry forest region, with representatives in America, Africa, Madagascar, and India. Additionally, a northern-hemisphere Subtropical forest region was identified with representatives in Asia and America, providing support for a link between Asian and American northern-hemisphere forests.

The estimation of chlorophyll-a (chl-a) concentration remains a great challenge in turbid waters due to their complex optical conditions. To improve chl-a estimation, this study aims to determine whether combined use of polarimetric synthetic-aperture radar (SAR) data has potential for improving the chl-a estimation from hyperspectral sensing reflectance for turbid waters such as those found in Lake Taihu, China. In situ measurements of hyperspectral reflectance data and water samples were collected over the lake corresponding to ENVISAT ASAR data. Semiempirical (two-band and three-band models) and empirical [multiple linear regression (MLR) and multilayer perceptron network (MLP)] models are compared to estimate the chl-a concentration from in situ hyperspectral reflectance and SAR data. The results show that there is a general underestimation of chl-a for concentrations higher than 26 ug/L, which is probably caused by the large spatial variation of chl-a in the study area. The results also demonstrate that the MLR model performs in a more stable manner than the MLP network does, while MLP underestimates low and high areas of chl-a concentrations in the lake. On the other hand, due to the availability of one scenic SAR data on the same day, our results show that the additional use of SAR data improved chl-a estimation very slightly in this case study, although the performance of vertical/vertical polarization SAR data was better than that of horizontal/horizontal polarization data in chl-a estimation. Potential future work in this subject could explore other measures of mutual information between SAR and hyperspectral optical data beyond the correlation and regression techniques described. Therefore, it is still necessary to apply more SAR data in varied turbid waters in the near future to determine how SAR data can be useful in the improvement of chl-a estimation.