900 Geschichte und Geografie
Refine
Has Fulltext
- yes (2)
Is part of the Bibliography
- yes (2)
Year of publication
- 2020 (2) (remove)
Document Type
- Doctoral Thesis (1)
- Working Paper (1)
Language
- English (2) (remove)
Keywords
- Altertum (1)
- Begrenzte Staatlichkeit (1)
- Europa (1)
- Europe (1)
- Fernerkundung (1)
- Geschichte (1)
- Global South (1)
- Moderne (1)
- Remote Sensing (1)
- Schnee (1)
- Snow (1)
- Vergleichende politische Wissenschaft (1)
- interdisciplinarity (1)
- local self-governance (1)
- weak statehood (1)
Institute
Sonstige beteiligte Institutionen
Worldwide, cold regions are undergoing significant alterations due to climate change. Snow, the most widely distributed cold region component, is highly sensitive to climate change. At the same time, snow itself profoundly impacts the Earth’s energy budget, biodiversity, and natural hazards, as well as hydropower management, freshwater management, and winter tourism/sports. Large parts of the cold regions in Europe are mountain areas, which are densely populated because of the various ecosystem services and socioeconomic well-being in mountains. At present, severe consequences caused by climate change have been observed in European mountains and their surrounding areas. Yet, large knowledge gaps hinder the development of effective regional and local adaptation strategies. Long-term and evidence-based regional studies are urgently needed to enhance the comprehension of regional responses to climate change.
Earth Observation (EO) provides long-term consistent records of the Earth’s surface. It is a great alternative and/or supplement to conventional in-situ measurements which are usually time-consuming, cost-intensive and logistically demanding, particularly for the poor accessibility of cold regions. With the assistance of EO, land surface dynamics in cold regions can be observed in an objective, repeated, synoptic and consistent way. Thanks to free and open data policies, long-term archives such as Landsat Archive and Sentinel Archive can be accessed free-of-charge. The high- to medium-resolution remote sensing imagery from these freely accessible archives gives EO-based time series datasets the capability to depict snow dynamics in European mountains from the 1980s to the present. In order to compile such a dataset, it is necessary to investigate the spatiotemporal availability of EO data, and develop a spatiotemporally transferable framework from which one can investigate snow dynamics.
Among the available EO image archives, the Landsat Archive has the longest uninterrupted records of the Earth’s land surface. Furthermore, its 30 m spatial resolution fulfils the requirements for snow monitoring in complex terrains. Landsat data can yield a time series of snow dynamics in mountainous areas from 1984 to the present. However, severe Landsat data gaps have occurred across certain regions of Europe. Moreover, the Landsat Level 1 Precision and Terrain (L1TP) data is scarcer (up to 50% less) in high-latitude mountainous areas than in low-latitude mountainous areas. Given the abovementioned facts, the Regional Snowline Elevation (RSE) is selected to characterize the snow dynamics in mountainous areas, as it can handle cloud obstructions in the optical images. In this thesis, I present a five-step framework to derive and densify RSE time series in European mountains, i.e. (1) pre-processing, (2) snow detection, (3) RSE retrieval, (4) time series densification, and (5) Regional Snowline Retreat Curve (RSRC) production.
The results of the intra-annual RSE variations show a uniquely high variation in the beginning of the ablation seasons in the Alpine catchment Tagliamento, mainly toward higher elevation. As for inter-annual variations of RSE, median RSE increases in all selected catchments, with an average speed of around 4.66 m ∙ a−1 (median) and 5.87 m ∙ a−1 (at the beginning of the ablation season). The fastest significant retreat is observed in the catchment Drac (10.66 m ∙ a−1, at the beginning of the ablation season), and the slowest significant retreat is observed in the catchment Uzh (1.74 m ∙ a−1, at the beginning of the ablation season). The increase of RSEs at the beginning of the ablation season is faster than the median RSEs, whose average difference is nearly 1.21 m ∙ a−1, particularly in the catchment Drac (3.72 m ∙ a−1). The results of the RSRCs show a significant rise in RSEs at the beginning of the ablation season, except for the Alpine catchment Alpenrhein and Var, and the Pyrenean catchment Ariege. It indicates that 11.8 and 3.97 degrees Celsius less per year are needed for the regional snowlines to reach the middle point of the RSRC in the Tagliamento and Tysa, respectively. The variation of air temperature is regarded as an example of a potential climate driver in this thesis. The retrieved monthly mean RSEs are highly correlated (mean correlation coefficient "R" ̅ = 0.7) with the monthly temperature anomalies, which are more significant in months with extremely low/high temperature. Another case study that investigates the correlation between river discharges and RSEs is carried out to demonstrate the potential consequences of the derived snowline dynamics. The correlation analysis shows a good correlation between river discharges and RSEs (correlation coefficient, R=0.52).
In this thesis, the developed framework signifies a better understanding of the snow dynamics in mountain areas, as well as their potential triggers and consequences. Nonetheless, an urgent need persists for: (1) validation data to assess long-term snow-related observations based on high-resolution EO data; (2) further studies to reveal interactions between snow and its ambient environment; and (3) regional and local adaptation-strategies coping with climate change. Further studies exploring the above-mentioned research gaps are urgently needed in the future.
The nucleus of statehood is situated at the local level: in the village, the neighborhood, the city district. This is where a community, beyond the level of the family, first develops collective rules that are intended to ensure its continued existence. But usually this is not the only level of governance at play. Above it, there are supralocal formations of power, varying in scope from regional networks to empires, which supplement the local orders or compete with them. The premise of this Research Unit is that local forms of self-governance are especially heterogeneous and prominent, wherever supralocal statehood exists in the mode of weak permeation. The central question of our approach is how local forms of self-governance work in this context. We will examine the relations to the state level as well as to other local groups as they develop over time; the scope and spatial contingency of forms of self-governance; their legitimization and the interdependency with the organization and collective identity of those groups which carry them out; finally, we will turn our attention to the significance of self-governance for the configuration of weak statehood. The empirical focus will be at the local level, which has so far been largely neglected in the research on governance beyond the state. In order to achieve this, we will work with case studies that are structured by categories and situated in geographical areas and time periods that lie outside of modern Europe with its particular development of statehood since the Late Middle Ages: in Antiquity, and in the Global South of the present. By incorporating these different time frames, we hope to contribute to overcoming the dichotomy between the modern and pre-modern era, which is often given canonical status. Our goal is to create a comparative analysis of different configurations of order as well as the development of a typology of patterns of local governance. The structure of the empirical comparison itself promises methodological insights, since it will entail recognizing, dealing with, and overcoming disciplinary limitations. Starting with the identification of typical patterns and processes, we hope to gain a better grasp of the mechanisms by which local configurations of order succeed, while at the same time advancing the theoretical debate. This will allow us to make an interdisciplinary contribution to the understanding of fundamental elements of statehood and local governance that are of central importance, especially in the context of weak statehood. The insights we hope to gain by adopting this historical perspective will contribute to understanding a present that is not based exclusively on its own, seemingly completely new preconditions, and will thus significantly sharpen the political analysis of various forms of governance.