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Large interannual variations in the measured growth rate of atmospheric carbon dioxide (CO 2) originate primarily from fluctuations in carbon uptake by land ecosystems. It remains uncertain, however, to what extent temperature and water availability control the carbon balance of land ecosystems across spatial and temporal scales. Here we use empirical models based on eddy covariance data and proce
Global vegetation models and terrestrial carbon cycle models are widely used for projecting the carbon balance of terrestrial ecosystems. Ensembles of such models show a large spread in carbon balance predictions, ranging from a large uptake to a release of carbon by the terrestrial biosphere, constituting a large uncertainty in the associated feedback to atmospheric CO 2 concentrations under glob
Crop models are increasingly used to simulate crop yields at the global scale, but so far there is no general framework on how to assess model performance. Here we evaluate the simulation results of 14 global gridded crop modeling groups that have contributed historic crop yield simulations for maize, wheat, rice and soybean to the Global Gridded Crop Model Intercomparison (GGCMI) of the Agricultu
Atmosfäriska partiklar (aerosoler) finns överallt i jordens atmosfär. Masskoncentrationen av dessa varierar kraftigt beroende på i vilken miljö man mäter. I stadsluft kan man uppmäta tiotals mikrogram per kubikmeter medan man i arktiska områden uppmäter nanogram per kubikmeter. Den kolhaltiga aerosolen utgör en betydande del av atmosfärsaerosolens massa och är känd för att påverka människors och dCarbonaceous aerosols are known to affect human health negatively and to affect the climate of Earth. As specific types of aerosols originate from specific sources, it is important to know the amount of aerosols emitted from each source. Aerosol source apportionment is an important tool in mitigating air pollution and improving air quality. The subject of this thesis was the evaluation and develop
Boreal forests exchange large amounts of carbon dioxide (CO2) with the atmosphere. A managed boreal landscape usually comprises various potential CO2 sinks and sources across forest stands of varying age classes, clear-cut areas, mires, and lakes. Due to this heterogeneity and complexity, large uncertainties exist regarding the net CO2 balance at the landscape scale. In this study, we present the
Idag har många organisationer, både inom privat och offentlig sektor, etablerat en närvaro på olika sociala medieplattformar. Det är av högsta relevans att granska aktörer i samhället som innehar en stor maktposition. Denna studie undersöker hur den svenska polisen använder Facebook som ett strategiskt verktyg för att kommunicera med medborgare, men också vilka möjligheter och faror som finns koppToday, many organizations, both within the private and the public sector, have developed a presence in different social media channels. It is of most importance to perpetually scrutinize entities because of their position of power in the society. This study examines how the Swedish Police use Facebook as a strategic tool to communicate with citizens, but also what the potential advantages and disa
Scholarly literature on science-policy interaction is typically dividedbetween advocating that science and policy need to be broughtcloser together or separated. In a recent article in this journal,Sundqvist and colleagues [Sundqvist et al. (2018) Oneworld ortwo? Science–policy interactions in the climate field, Critical PolicyStudies, 12:4, 448–468] proposed a typology that structures thisdebate.
To overcome soil nutrient limitation, many plants have developed complex nutrient acquisition strategies including altering root morphology, root hair formation or colonization by arbuscular mycorrhizal fungi (AMF). The interactions of these strategies and their plasticity are, however, affected by soil nutrient status throughout plant growth. Such plasticity is decisive for plant phosphorus (P) a
Understanding responses by changes in land use and land cover (LULC) and climate over the past decades on streamflow in the upper Blue Nile River basin is important for water management and water resource planning in the Nile basin at large. This study assesses the long-term trends of rainfall and streamflow and analyses the responses of steamflow to changes in LULC and climate in the upper Blue N
Northern peatlands store nearly one-third of terrestrial carbon (C) stocks while covering only 3% of the global landmass; nevertheless, the drivers of C cycling in these often-waterlogged ecosystems are different from those that control C dynamics in upland forested soils. To explore how multiple abiotic and biotic characteristics of bogs interact to shape microbial activity in a northern, foreste
The Arctic has warmed more than twice as fast as the global average since the late twentieth century, a phenomenon known as Arctic amplification (AA). Recently, there have been considerable advances in understanding the physical contributions to AA, and progress has been made in understanding the mechanisms that link it to midlatitude weather variability. Observational studies overwhelmingly suppo
Dense time series of Landsat 8 and Sentinel-2 imagery are creating exciting new opportunities to monitor, map, and characterize temporal dynamics in land surface properties with unprecedented spatial detail and quality. By combining imagery from the Landsat 8 Operational Land Imager and the MultiSpectral Instrument on-board Sentinel-2A and -2B, the remote sensing community now has access to modera
In a previous study, Dutch children with phenylketonuria (PKU) were found to be slightly shorter than their healthy counterparts. In the literature, it has been hypothesized that a higher protein intake is necessary to optimize growth in PKU patients. The study aimed to investigate whether protein intake (total, natural and protein substitute) in this group might be an explanatory factor for the o
Popular Abstract in Swedish Anhöriga – aspekter på börda, livstillfredsställelse och effekter av stöd. Med en ökande befolkning av äldre och en samtidig minskning av möjligheter till hjälpinsatser inom såväl kommunalt som landstingsstyrd vård och omsorg, kommer många av oss ta hand om äldre familjemedlemmar, släktingar och vänner. Hur kommer detta att påverka oss? Ungefär 20 % av den vuxna befolWith an aging population and a reduction in social services provided by the municipality, a huge majority of us will take care of elderly family members, relatives and friends in need of assistance. How will this affect our lives? Approximately 20% of the adult population in Sweden, mainly middle-aged persons, identify themselves as family caregivers. Many of these caregivers are working and, at
Treeline encroachments and retractions can provide global-scale feedbacks to the climate system, and treeline dynamics are therefore of great relevance for understanding global climate variability. To assess the accuracy of long-term treeline simulations based on the generalized dynamic vegetation model LPJ-GUESS, we simulate European Arctic treeline dynamics over the past 9000 years and compare t
Holocene summer temperature reconstructions from northern Europe based on sedimentary pollen records suggest an onset of peak summer warmth around 9,000 years ago. However, pollen-based temperature reconstructions are largely driven by changes in the proportions of tree taxa, and thus the early-Holocene warming signal may be delayed due to the geographical disequilibrium between climate and tree p
Carbon assimilation defined as the overall rate of fixation of carbon through the process of photosynthesis is central to the climate change research. The present study compares the two well-known algorithms in satellite based carbon assimilation estimation, the Vegetation Photosynthesis Model (VPM) and the MOD 17A2 GPP Model, over the tropical forest types in India for a period of two years (Sept
We evaluated the seasonality of CO2 fluxes simulated by nine terrestrial ecosystem models of the TRENDY project against (1) the seasonal cycle of gross primary production (GPP) and net ecosystem exchange (NEE) measured at flux tower sites over different biomes, (2) gridded monthly Model Tree Ensembles-estimated GPP (MTE-GPP) and MTE-NEE obtained by interpolating many flux tower measurements with a
Spruce bark beetle outbreaks are common in Norway spruce forests following windstorm damage, due to ample availability of brood material. The realization of an outbreak depends on factors regulating the Ips typographus population dynamics, such as weather conditions and salvage cutting. In this study, we take an ecosystem modelling approach to analyse the influence of multiple environmental factor
