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More than a billion people rely on water from rivers sourced in High Mountain Asia (HMA), a significant portion of which is derived from snow and glacier melt. Rural communities are heavily dependent on the consistency of runoff, and are highly vulnerable to shifts in their local environment brought on by climate change. Despite this dependence, the impacts of climate change in HMA remain poorly constrained due to poor process understanding, complex terrain, and insufficiently dense in-situ measurements.
HMA's glaciers contain more frozen water than any region outside of the poles. Their extensive retreat is a highly visible and much studied marker of regional and global climate change. However, in many catchments, snow and snowmelt represent a much larger fraction of the yearly water budget than glacial meltwaters. Despite their importance, climate-related changes in HMA's snow resources have not been well studied.
Changes in the volume and distribution of snowpack have complex and extensive impacts on both local and global climates. Eurasian snow cover has been shown to impact the strength and direction of the Indian Summer Monsoon -- which is responsible for much of the precipitation over the Indian Subcontinent -- by modulating earth-surface heating. Shifts in the timing of snowmelt have been shown to limit the productivity of major rangelands, reduce streamflow, modify sediment transport, and impact the spread of vector-borne diseases. However, a large-scale regional study of climate impacts on snow resources had yet to be undertaken.
Passive Microwave (PM) remote sensing is a well-established empirical method of studying snow resources over large areas. Since 1987, there have been consistent daily global PM measurements which can be used to derive an estimate of snow depth, and hence snow-water equivalent (SWE) -- the amount of water stored in snowpack. The SWE estimation algorithms were originally developed for flat and even terrain -- such as the Russian and Canadian Arctic -- and have rarely been used in complex terrain such as HMA.
This dissertation first examines factors present in HMA that could impact the reliability of SWE estimates. Forest cover, absolute snow depth, long-term average wind speeds, and hillslope angle were found to be the strongest controls on SWE measurement reliability. While forest density and snow depth are factors accounted for in modern SWE retrieval algorithms, wind speed and hillslope angle are not. Despite uncertainty in absolute SWE measurements and differences in the magnitude of SWE retrievals between sensors, single-instrument SWE time series were found to be internally consistent and suitable for trend analysis.
Building on this finding, this dissertation tracks changes in SWE across HMA using a statistical decomposition technique. An aggregate decrease in SWE was found (10.6 mm/yr), despite large spatial and seasonal heterogeneities. Winter SWE increased in almost half of HMA, despite general negative trends throughout the rest of the year. The elevation distribution of these negative trends indicates that while changes in SWE have likely impacted glaciers in the region, climate change impacts on these two pieces of the cryosphere are somewhat distinct.
Following the discussion of relative changes in SWE, this dissertation explores changes in the timing of the snowmelt season in HMA using a newly developed algorithm. The algorithm is shown to accurately track the onset and end of the snowmelt season (70% within 5 days of a control dataset, 89% within 10). Using a 29-year time series, changes in the onset, end, and duration of snowmelt are examined. While nearly the entirety of HMA has experienced an earlier end to the snowmelt season, large regions of HMA have seen a later start to the snowmelt season. Snowmelt periods have also decreased in almost all of HMA, indicating that the snowmelt season is generally shortening and ending earlier across HMA.
By examining shifts in both the spatio-temporal distribution of SWE and the timing of the snowmelt season across HMA, we provide a detailed accounting of changes in HMA's snow resources. The overall trend in HMA is towards less SWE storage and a shorter snowmelt season. However, long-term and regional trends conceal distinct seasonal, temporal, and spatial heterogeneity, indicating that changes in snow resources are strongly controlled by local climate and topography, and that inter-annual variability plays a significant role in HMA's snow regime.
Background
In health research, indicators of socioeconomic status (SES) are often used interchangeably and often lack theoretical foundation. This makes it difficult to compare results from different studies and to explore the relationship between SES and health outcomes. To aid researchers in choosing appropriate indicators of SES, this article proposes and tests a theory-based selection of SES indicators using chronic back pain as a health outcome.
Methods
Strength of relationship predictions were made using Brunner & Marmot’s model of ‘social determinants of health’. Subsequently, a longitudinal study was conducted with 66 patients receiving in-patient treatment for chronic back pain. Sociodemographic variables, four SES indicators (education, job position, income, multidimensional index) and back pain intensity and disability were obtained at baseline. Both pain dimensions were assessed again 6 months later. Using linear regression, the predictive strength of each SES indicator on pain intensity and disability was estimated and compared to the theory based prediction.
Results
Chronic back pain intensity was best predicted by the multidimensional index (beta = 0.31, p < 0.05), followed by job position (beta = 0.29, p < 0.05) and education (beta = −0.29, p < 0.05); whereas, income exerted no significant influence. Back pain disability was predicted strongest by education (beta = −0.30, p < 0.05) and job position (beta = 0.29, p < 0.05). Here, multidimensional index and income had no significant influence.
Conclusions
The choice of SES indicators influences predictive power on both back pain dimensions, suggesting SES predictors cannot be used interchangeably. Therefore, researchers should carefully consider prior to each study which SES indicator to use. The introduced framework can be valuable in supporting this decision because it allows for a stable prediction of SES indicator influence and their hierarchy on a specific health outcomes.
Background Low back pain (LBP) is a common pain syndrome in athletes, responsible for 28% of missed training days/year. Psychosocial factors contribute to chronic pain development. This study aims to investigate the transferability of psychosocial screening tools developed in the general population to athletes and to define athlete-specific thresholds.
Methods Data from a prospective multicentre study on LBP were collected at baseline and 1-year follow-up (n=52 athletes, n=289 recreational athletes and n=246 non-athletes). Pain was assessed using the Chronic Pain Grade questionnaire. The psychosocial Risk Stratification Index (RSI) was used to obtain prognostic information regarding the risk of chronic LBP (CLBP). Individual psychosocial risk profile was gained with the Risk Prevention Index – Social (RPI-S). Differences between groups were calculated using general linear models and planned contrasts. Discrimination thresholds for athletes were defined with receiver operating characteristics (ROC) curves.
Results Athletes and recreational athletes showed significantly lower psychosocial risk profiles and prognostic risk for CLBP than non-athletes. ROC curves suggested discrimination thresholds for athletes were different compared with non-athletes. Both screenings demonstrated very good sensitivity (RSI=100%; RPI-S: 75%–100%) and specificity (RSI: 76%–93%; RPI-S: 71%–93%). RSI revealed two risk classes for pain intensity (area under the curve (AUC) 0.92(95% CI 0.85 to 1.0)) and pain disability (AUC 0.88(95% CI 0.71 to 1.0)).
Conclusions Both screening tools can be used for athletes. Athlete-specific thresholds will improve physicians’ decision making and allow stratified treatment and prevention.
Together with the gradual change of mean values, ongoing climate change is projected to increase frequency and amplitude of temperature and precipitation extremes in many regions of Europe. The impacts of such in most cases short term extraordinary climate situations on terrestrial ecosystems are a matter of central interest of recent climate change research, because it can not per se be assumed that known dependencies between climate variables and ecosystems are linearly scalable. So far, yet, there is a high demand for a method to quantify such impacts in terms of simultaneities of event time series.
In the course of this manuscript the new statistical approach of Event Coincidence Analysis (ECA) as well as it's R implementation is introduced, a methodology that allows assessing whether or not two types of event time series exhibit similar sequences of occurrences. Applications of the method are presented, analyzing climate impacts on different temporal and spacial scales: the impact of extraordinary expressions of various climatic variables on tree stem variations (subdaily and local scale), the impact of extreme temperature and precipitation events on the owering time of European shrub species (weekly and country scale), the impact of extreme temperature events on ecosystem health in terms of NDVI (weekly and continental scale) and the impact of El Niño and La Niña events on precipitation anomalies (seasonal and global scale).
The applications presented in this thesis refine already known relationships based on classical methods and also deliver substantial new findings to the scientific community: the widely known positive correlation between flowering time and temperature for example is confirmed to be valid for the tails of the distributions while the widely assumed positive dependency between stem diameter variation and temperature is shown to be not valid for very warm and very cold days. The larger scale investigations underline the sensitivity of anthrogenically shaped landscapes towards temperature extremes in Europe and provide a comprehensive global ENSO impact map for strong precipitation events.
Finally, by publishing the R implementation of the method, this thesis shall enable other researcher to further investigate on similar research questions by using Event Coincidence Analysis.
Historical narratives play an important role in constructing contemporary notions of citizenship. They are sites on which ideas of the nation are not only reaffirmed but also contested and reframed. In contemporary Germany, dominant narratives of the country’s modern history habitually focus on the legacy of the Third Reich and tend to marginalize the country’s rich and highly complex histories of immigration. The article addresses this commemorative void in relation to Berlin’s urban landscape. It explores how the city’s multilayered architecture provides locations for the articulation of marginal memories—and hence sites of urban citizenship—that are often denied to immigrant communities on a national scale. Through a detailed examination of a small celebration in 1965 that marked the anniversary of the founding of the modern Turkish republic, the article engages with the layers of history that coalesce around such sites in Berlin.
The article explores how recent changes in the governance of employment services in three European countries (Denmark, Germany and Norway) have influenced accountability relationships. The overall assumption in the growing literature about accountability is that the number of actors involved in accountability arrangements is rising, that accountability relationships are becoming more numerous and complex, and that these changes may lead to contradictory accountability relationships, and finally to ‘multi accountability disorder’. The article tries to explore these assumptions by analysing the different actors involved and the information requested in the new governance arrangements in all three countries. It concludes that the considerable changes in organizational arrangements and more managerial information demanded and provided have led to more shared forms of accountability. Nevertheless, a clear development towards less political or administrative accountability could not be observed.
Traineeprogramme können im öffentlichen Dienst zur Rekrutierung und Ausbildung von Nachwuchskräften dienen. Solche Programme werden, im Gegensatz zur Privatwirtschaft, wo diese schon seit einigen Jahrzehnten Anwendung finden, im deutschen öffentlichen Dienst erst seit einigen Jahren durchgeführt. Eine erste empirische Erhebung zeigt nun, dass Traineeprogramme im öffentlichen Sektor gut geeignet sind, um Nachwuchskräfte auszubilden und in der Organisation zu sozialisieren. Als entscheidende Einflussfaktoren konnten eine klare Struktur des Programms, ein effektives off-the-job Training, bereichsübergreifende Projektarbeit, der Umfang der Betreuung der Trainees und der Einsatz der jeweiligen Behördenleitung für das Programm identifiziert werden. Deutlich wurde auch, dass während der Einführung eines Traineeprogramms die Trainee-Betreuer entsprechend vorbereitet werden müssen und in den Behörden Akzeptanz für diese neue Form der Nachwuchsgewinnung geschaffen werden muss (Change Management). Die Ergebnisse zeigen jedoch ebenso, dass sich solche Programme nicht zur Personalentwicklung bereits Beschäftigter eignen.
Dieses Promotionsvorhaben wird versuchen den Begriff der Due-Diligence im Rahmen des Menschenrechts- und Umweltschutzes weiterzuentwickeln. Dieser Terminus verweist auf einen vernünftigen Verhaltensstandard und wird öfters zum Schädigungsverbot in Verbindung gebracht. Ein bekanntes Synonym dafür ist die „Sorgfaltspflicht“. Nach dieser Norm müssen alle voraussehbaren Verletzungsrisiken (Personen-, Sach- und Umwelt) durch die Ergreifung von allen nötigen und angemessenen Maßnahmen vorgebeugt werden (s. z.B. Trail-Smelter und Korfu-Kanal Entscheidung). Dieser Begriff wird gegenwärtig weltweit verwendet um Globalisierungsprobleme zu adressieren, wie z.B. der mangelnde Klimaschutz oder die mangelnde Reglementierung von Transnationalen Unternehmen. Die Emergenz dieser offenen und allgemeinen Norm ist eindeutig und wird durch die Tatsache erleichtert, dass sie in viele Rechtssysteme vorhanden ist. Zum Beispiel, in dem bekannten Urgenda v. Holland Fall, fordert der Gerichtshof von Den Haag vom Staat eine angemessenere Aufsicht im Klimaschutz, da die ursprünglichen Reduktionsziele von Treibhausgasemissionen nicht die wissenschaftlichen Anforderungen entsprachen. Dieser Fall hat viele andere Klagen inspiriert. Der französische Gesetzgeber verpflichtet darüber hinaus seit kurzem mit dem Gesetz zur „devoir de vigilance“ herrschende Unternehmen zur Veröffentlichung eines ‚Sorgfaltsplans‘, so dass die Auswirkungen des gesamten Unternehmens auf die Menschenrechte und die Umwelt effektiv vorgebeugt werden. Dieses Gesetz hat auch die letzten UN-Vertragsverhandlungen bzgl. Multinationalen Unternehmen geprägt. In Anbetracht dessen, wird diese rechtsvergleichende Studie die Verrechtlichung der Norm und ihre Verbreitung in anderen Rechtssysteme untersuchen, so dass der Menschenrechts- und Umweltschutz effektiv gewährleistet werden kann, auch wenn die Politik und Unternehmen es verhindern wollen.