155 research outputs found
Future permafrost conditions along environmental gradients in Zackenberg, Greenland
The future development of ground temperatures in permafrost areas is
determined by a number of factors varying on different spatial and temporal
scales. For sound projections of impacts of permafrost thaw, scaling
procedures are of paramount importance. We present numerical simulations of
present and future ground temperatures at 10 m resolution for a 4 km long
transect across the lower Zackenberg valley in northeast Greenland. The results are
based on stepwise downscaling of future projections derived from general
circulation model using observational data, snow redistribution modeling, remote
sensing data and a ground thermal model. A comparison to in situ measurements
of thaw depths at two CALM sites and near-surface ground temperatures at 17
sites suggests agreement within 0.10 m for the maximum thaw depth and
1 °C for annual average ground temperature. Until 2100, modeled
ground temperatures at 10 m depth warm by about 5 °C and the active
layer thickness increases by about 30%, in conjunction with a warming of
average near-surface summer soil temperatures by 2 °C. While ground
temperatures at 10 m depth remain below 0 °C until 2100 in all model
grid cells, positive annual average temperatures are modeled at 1 m depth
for a few years and grid cells at the end of this century. The ensemble of
all 10 m model grid cells highlights the significant spatial
variability of the ground thermal regime which is not accessible in
traditional coarse-scale modeling approaches
Future permafrost conditions along environmental gradients in Zackenberg, Greenland
The future development of ground temperatures in permafrost areas is
determined by a number of factors varying on different spatial and temporal
scales. For sound projections of impacts of permafrost thaw, scaling
procedures are of paramount importance. We present numerical simulations of
present and future ground temperatures at 10 m resolution for a 4 km long
transect across the lower Zackenberg valley in northeast Greenland. The results are
based on stepwise downscaling of future projections derived from general
circulation model using observational data, snow redistribution modeling, remote
sensing data and a ground thermal model. A comparison to in situ measurements
of thaw depths at two CALM sites and near-surface ground temperatures at 17
sites suggests agreement within 0.10 m for the maximum thaw depth and
1 °C for annual average ground temperature. Until 2100, modeled
ground temperatures at 10 m depth warm by about 5 °C and the active
layer thickness increases by about 30%, in conjunction with a warming of
average near-surface summer soil temperatures by 2 °C. While ground
temperatures at 10 m depth remain below 0 °C until 2100 in all model
grid cells, positive annual average temperatures are modeled at 1 m depth
for a few years and grid cells at the end of this century. The ensemble of
all 10 m model grid cells highlights the significant spatial
variability of the ground thermal regime which is not accessible in
traditional coarse-scale modeling approaches
Life cycle modelling of environmental impacts of application of processed organic municipal solid waste on agricultural land (EASEWASTE)
A model capable of quantifying the potential environmental impacts of agricultural application of composted or anaerobically digested source-separated organic municipal solid waste (MSW) is presented. In addition to the direct impacts, the model accounts for savings by avoiding the production and use of commercial fertilizers. The model is part of a larger model, Environmental Assessment of Solid Waste Systems and Technology (EASEWASTE), developed as a decisionsupport model, focusing on assessment of alternative waste management options. The environmental impacts of the land application of processed organic waste are quantified by emission coefficients referring to the composition of the processed waste and related to specific crop rotation as well as soil type. The model contains several default parameters based on literature data, field experiments and modelling by the agro-ecosystem model, Daisy. All data can be modified by the user allowing application of the model to other situations. A case study including four scenarios was performed to illustrate the use of the model. One tonne of nitrogen in composted and anaerobically digested MSW was applied as fertilizer to loamy and sandy soil at a plant farm in western Denmark. Application of the processed organic waste mainly affected the environmental impact categories global warming (0.4–0.7 PE), acidification (–0.06 (saving)–1.6 PE), nutrient enrichment (–1.0 (saving)–3.1 PE), and toxicity. The main contributors to these categories were nitrous oxide formation (global warming), ammonia volatilization (acidification and nutrient enrichment), nitrate losses (nutrient enrichment and groundwater contamination), and heavy metal input to soil (toxicity potentials). The local agricultural conditions as well as the composition of the processed MSW showed large influence on the environmental impacts. A range of benefits, mainly related to improved soil quality from long-term application of the processed organic waste, could not be generally quantified with respect to the chosen life cycle assessment impact categories and were therefore not included in the model. These effects should be considered in conjunction with the results of the life cycle assessment
Attendance in a national screening program for diabetic retinopathy:a population-based study of 205,970 patients
AIMS: A nationwide diabetic retinopathy (DR) screening program has been established in Denmark since 2013. We aimed to perform an evaluation of adherence to DR screenings and to examine whether non-adherence was correlated to DR progression. METHODS: The population consisted of a register-based cohort, who participated in the screening program from 2013 to 2018. We analyzed age, gender, marital status, DR level (International Clinical DR severity scale, none, mild-, moderate-, severe non-proliferative DR (NPDR) and proliferative DR (PDR)), comorbidities and socioeconomic factors. The attendance pattern of patients was grouped as either timely (no delays > 33%), delayed (delays > 33%) or one-time attendance (unexplained). RESULTS: We included 205,970 patients with 591,136 screenings. Rates of timely, delayed and one-time attendance were 53.0%, 35.5% and 11.5%, respectively. DR level at baseline was associated with delays (mild-, moderate-, severe NPDR and PDR) and one-time attendance (moderate-, severe NPDR and PDR) with relative risk ratios (RRR) of 1.68, 2.27, 3.14, 2.44 and 1.18, 2.07, 1.26, respectively (P < 0.05). Delays at previous screenings were associated with progression to severe NPDR or PDR (hazard ratio (HR) 2.27, 6.25 and 12.84 for 1, 2 and 3+ delays, respectively). Any given delay doubled the risk of progression (HR 2.28). CONCLUSIONS: In a national cohort of 205,970 patients, almost half of the patients attended DR screening later than scheduled or dropped out after first screening episode. This was, in particular, true for patients with any levels of DR at baseline. DR progression in patients with delayed attendance, increased with the number of missed appointments
The politicisation of evaluation: constructing and contesting EU policy performance
Although systematic policy evaluation has been conducted for decades and has been growing strongly within the European Union (EU) institutions and in the member states, it remains largely underexplored in political science literatures. Extant work in political science and public policy typically focuses on elements such as agenda setting, policy shaping, decision making, or implementation rather than evaluation. Although individual pieces of research on evaluation in the EU have started to emerge, most often regarding policy “effectiveness” (one criterion among many in evaluation), a more structured approach is currently missing. This special issue aims to address this gap in political science by focusing on four key focal points: evaluation institutions (including rules and cultures), evaluation actors and interests (including competencies, power, roles and tasks), evaluation design (including research methods and theories, and their impact on policy design and legislation), and finally, evaluation purpose and use (including the relationships between discourse and scientific evidence, political attitudes and strategic use). The special issue considers how each of these elements contributes to an evolving governance system in the EU, where evaluation is playing an increasingly important role in decision making
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