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The forcing from the anthropogenic heat flux (AHF), i.e. the dissipation of primary energy consumed by the human civilisation, produces a direct climate warming. Today, the globally averaged AHF is negligibly small compared to the indirect forcing from greenhouse gas emissions. Locally or regionally, though, it has a significant impact. Historical observations show a constant exponential growth of worldwide energy production. A continuation of this trend might be fueled or even amplified by the exploration of new carbon-free energy sources like fusion power. In such a scenario, the impacts of the AHF become a relevant factor for anthropogenic post-greenhouse gas climate change on the global scale, as well.
This master thesis aims at estimating the climate impacts of such a growing AHF forcing. In the first part of this work, the AHF is built into simple and conceptual, zero- and one-dimensional Energy Balance Models (EBMs), providing quick order of magnitude estimations of the temperature impact. In the one-dimensional EBM, the ice-albedo feedback from enhanced ice melting due to the AHF increases the temperature impact significantly compared to the zero-dimensional EBM.
Additionally, the forcing is built into a climate model of intermediate complexity, CLIMBER-3α. This allows for the investigation of the effect of localised AHF and gives further insights into the impact of the AHF on processes like the ocean heat uptake, sea ice and snow pattern changes
and the ocean circulation.
The global mean temperature response from the AHF today is of the order of 0.010 − 0.016 K in all reasonable model configurations tested. A transient tenfold increase of this forcing heats up the Earth System additionally by roughly 0.1 − 0.2 K in the presented models. Further growth
can also affect the tipping probability of certain climate elements.
Most renewable energy sources do not or only partially contribute to the AHF forcing as the energy from these sources dissipates anyway. Hence, the transition to a (carbon-free) renewable energy mix, which, in particular, does not rely on nuclear power, eliminates the local and global climate impacts from the increasing AHF forcing, independent of the growth of energy production.
Geomagnetic field modeling using spherical harmonics requires the inversion for hundreds to thousands of parameters. This large-scale problem can always be formulated as an optimization problem, where a global minimum of a certain cost function has to be calculated. A variety of approaches is known in order to solve this inverse problem, e.g. derivative-based methods or least-squares methods and their variants. Each of these methods has its own advantages and disadvantages, which affect for example the applicability to non-differentiable functions or the runtime of the corresponding algorithm.
In this work, we pursue the goal to find an algorithm which is faster than the established methods and which is applicable to non-linear problems. Such non-linear problems occur for example when estimating Euler angles or when the more robust L_1 norm is applied. Therefore, we will investigate the usability of stochastic optimization methods from the CMAES family for modeling the geomagnetic field of Earth's core. On one hand, basics of core field modeling and their parameterization are discussed using some examples from the literature. On the other hand, the theoretical background of the stochastic methods are provided. A specific CMAES algorithm was successfully applied in order to invert data of the Swarm satellite mission and to derive the core field model EvoMag. The EvoMag model agrees well with established models and observatory data from Niemegk. Finally, we present some observed difficulties and discuss the results of our model.
Conventional wisdom holds that large sums of money poured into election campaigns are the gateway to corruption. Allegations of the corrupting influence of money in politics and policy are widespread on the national level. Yet, little empirical evidence has advanced the understanding of such a link on the local level, coupled with blurred corruption measures. This master’s thesis tests the effect of campaign finance on public procurement corruption risks in Colombian municipalities, focusing on donations, small donations, and financial disclosure. To that end, I seized publicly disclosed contribution-level data from the 2015 municipal elections and a novel index of institutionalized public procurement corruption risks based upon contract-level data from the near population of local governments. The analysis shows that donations are negatively associated with overall corruption risk, yet they affect specific corruption risks differently. By contrast, small donations seem to correlate positively with direct awarding for a sub-sample of medium-sized municipalities, whereas in their large-sized counterparts the effect of the former on institutionalized corruption is adverse. Finally, financial misreporting is positively linked with market competition restrictions and direct awarding. In the conclusion, I discuss the implications of these findings for future research and outline a series of policy recommendations.
The involvement of the two German states in Korea during the 1950s in the context of the Cold War
(2020)
This master thesis will analyze the background of the involvement of the Federal Republic of Germany (FRG) and the German Democratic Republic (GDR) in Korea during the 1950s in the context of the Cold War. In both Korean states, the Democratic People’s Republic of Korea (DPRK) as well as the Republic of Korea (ROK), the so-called humanitarian aid that was provided to them in the form of medical and economic assistance to help surmount the hardship of the postwar period is remembered with great appreciation to this day. However, critical views on the German engagement in Korea are still relatively hard to find. In this paper, two exemplary cases will be studied: the GDR’s city reconstruction project in the North Korean cities of Hamheung and Heungnam and the FRG’s medical assistance to the ROK by means of the West German Red Cross Hospital in Busan. By looking at primary sources like governmental documents, this thesis will examine the geopolitical conditions and particular national interests that stood behind the German development and humanitarian aid for the Korean states at that time, thus shedding light on the political goals the two German states pursued, and the benefit they expected to derive from their engagement in Korea. Sources consulted include primary archival materials, secondary sources like monographs, journal articles, contemporary newspaper articles, and interviews with contemporary witnesses.
This thesis aims at presenting in an organized fashion the required basics to understand the Glauber dynamics as a way of simulating configurations according to the Gibbs distribution of the Curie-Weiss Potts model. Therefore, essential aspects of discrete-time Markov chains on a finite state space are examined, especially their convergence behavior and related mixing times. Furthermore, special emphasis is placed on a consistent and comprehensive presentation of the Curie-Weiss Potts model and its analysis. Finally, the Glauber dynamics is studied in general and applied afterwards in an exemplary way to the Curie-Weiss model as well as the Curie-Weiss Potts model. The associated considerations are supplemented with two computer simulations aiming to show the cutoff phenomenon and the temperature dependence of the convergence behavior.
Gender-inclusive language has evolved into a much-debated topic during the past years, discussed interdisciplinarily from theoretical to psycholinguistics, sociology, and economy – and by anyone who uses language.
Studies on German that primarily relied on questionnaires (reviewed in Braun et al. 2005), cloze tests (Klein 1988), and categorisation tasks with picture matching (Irmen & Köhncke 1996) disqualify the generically used masculine forms as pseudo-generic – failing their grammatically prescribed function to include referents of any Gender. Gender-balanced expressions (pair and split forms like Lehrer und Lehrerinnen) make explicit reference to female presence and participation, and thus elevate a more equitable interpretation.
Online methods to investigate the processing of Gender-sensitive language are surprisingly rare among research on the phenomenon, except for reaction time measures (Irmen & Köhncke 1996, Irmen & Kaczmarek 2000) and eye-tracking in reading (Irmen & Schumann 2011).
In addition, Gender-neutral language (GNL) has not been focused on in the majority of experiments, and when it was among the stimuli, results were inconclusive (De Backer & De Cuypere 2012) or found such alternatives to be ineffective (resembling masculine generics, Braun et al. 2005), despite the fact that guidelines on non-discriminatory language use commonly recommend these.
Gender-neutral (GN) expressions for personal reference in German include
• nominalised participles; nominalisations in general: Interessierte, Lehrende
• collective singulars: Publikum, Kollegium
• compounds (e.g., with a notion of “-person”): Ansprechpersonen, Lehrkräfte
• paraphrases that background a (gendered) subject: e.g., passives, relatives
In a visual world eye-tracking study, the comprehension of plural generics using masculine nouns and GN forms was tested for roles and occupations.
In complex stimulus scenarios, reference had to be established to referent images presented on a screen. At the end of each item, a question was asked in order to (re)identify the image that matched the referents of the respective setting best. Images depicted 1) a single person (protagonist), 2) an all-female group, 3) an all-male group, 4) a mixed Gender group of female and male members. The group referents were introduced with either a) masculine nouns (die Lehrer), b) female-specific feminine nouns (die Lehrerinnen), or c) one of the upper three nominal GN variants (die Lehrkräfte).
Results confirm the frequent male bias in masculine forms that are used as generics, that is, their male-specific interpretation. Furthermore, stereotypicality of nouns had an impact on responses. The GN alternatives, which are generally known to aim for indefinite reference (“marked” for Gender-fair language) were found to be most qualified to elicit mixed Gender group interpretations. When reference was established with GN terms, an inclusive response was consistently elicited. This was both indicated by eye movements and response proportions, but to a different extent depending on the particular GN noun type. Concepts that abstract from Gender in their linguistic forms (“neutralising” it) appear to be more inclusive, and thus better candidates for generic reference than masculines.
“Jewish, Gay and Proud”
(2020)
This publication examines the foundation and institutional integration of the first gay-lesbian synagogue Beth Chayim Chadashim, which was founded in Los Angeles in 1972. As early as June 1974, the synagogue was admitted to the Union of American Hebrew Congregations, the umbrella organization of the Reform congregations in the United States. Previously, the potential acceptance of a congregation by and for homosexual Jews triggered an intense and broad debate within Reform Judaism. The work asks how it was possible to successfully establish a gay-lesbian synagogue at a time when homosexual acts were considered unnatural and contrary to tradition by almost the entire Jewish community. The starting point of the argumentation is, in addition to general changes in American synagogues after World War II, the assumption that Los Angeles was the most suitable place for this foundation. Los Angeles has an impressive queer history and the Jewish community was more open, tolerant and innovative here than its counterpart on the East Coast. The Metropolitan Community Church was also founded in the city, and as the largest religious institution for homosexual Christians, it also served as the birthplace of queer synagogues.
Reform Judaism was chosen as the place of institutional integration of the community because a relative openness for such an endeavor was only seen here. Responsa written in response to a potential admission of Beth Chayim Chadashim can be used to understand the arguments and positions of rabbis and psychologists regarding homosexuality and communities for homosexual Jews in the early 1970s.
Ultimately, the commitment and dedication of the congregation and its heterosexual supporters convinced the decision-makers in Reform Judaism. The decisive impulse to question the situation of homosexual Jews in Judaism came from Los Angeles. With its analysis, the publication contributes to the understanding of Queer Jewish History in general and queer synagogues in particular.
Dynamic earthquake rupture modeling provides information on the rupture physics as the rupture velocity, frictions or tractions acting during the rupture process. Nevertheless, as often based on spatial gridded preset geometries, dynamic modeling is depending on many free parameters leading to both a high non-uniqueness of the results and large computation times. That decreases the possibilities of full Bayesian error analysis.
To assess the named problems we developed the quasi-dynamic rupture model which is presented in this work. It combines the kinematic Eikonal rupture model with a boundary element method for quasi-static slip calculation.
The orientation of the modeled rupture plane is defined by a previously performed moment tensor inversion. The simultanously inverted scalar seismic moment allows an estimation of the extension of the rupture. The modeled rupture plane is discretized by a set of rectangular boundary elements. For each boundary element an applied traction vector is defined as the boundary value.
For insights in the dynamic rupture behaviour the rupture front propagation is calculated for incremental time steps based on the 2D Eikonal equation. The needed location-dependent rupture velocity field is assumed to scale linearly with a layered shear wave velocity field.
At each time all boundary elements enclosed within the rupture front are used to calculate the quasi-static slip distribution. Neither friction nor stress propagation are considered. Therefore the algorithm is assumed to be “quasi-static”. A series of the resulting quasi-static slip snapshots can be used as a quasi-dynamic model of the rupture process.
As many a priori information is used from the earth model (shear wave velocity and elastic parameters) and the moment tensor inversion (rupture extension and orientation) our model is depending on few free parameters as the traction field, the linear factor between rupture and shear wave velocity and the nucleation point and time. Hence stable and fast modeling results are obtained as proven from the comparison to different infinite and finite static crack solutions.
First dynamic applications show promissing results. The location-dependent rise time is automatically derived by the model. Different simple kinematic models as the slip-pulse or the penny-shaped crack model can be reproduced as well as their corresponding slip rate functions. A source time function (STF) approximation calculated from the cumulative sum of moment rates of each boundary element gives results similar to theoretical and empirical known STFs.
The model was also applied to the 2015 Illapel earthquake. Using a simple rectangular rupture geometry and a 2-layered traction regime yields good estimates of both the rupture front propagation and the slip patterns which are comparable to literature results. The STF approximation shows a good fit with previously published STFs.
The quasi-dynamic rupture model is hence able to fastly calculate reproducable slip results. That allows to test full Bayesian error analysis in the future. Further work on a full seismic source inversion or even a traction field inversion can also extend the scope of our model.
Alluvial fans are important geomorphic markers and sedimentary archives of tectonic and climatic changes. Hence, basins providing perfect studying conditions can often be found in arid regions due to the low weathering impact and thus well preservation of sedimentary features. Twelve samples for optically/infrared stimulated luminescence (OSL/IRSL) dating and one depth profile for cosmogenic radionuclide dating (10Be) were collected in the Santa Maria Valley in NW Argentina, where the exceptional preservation of several generations of alluvial fans allow exploring the external forcing conditions that led to repeated cycles of incision and aggradation. The results of the OSL/IRSL dating yielded ages ranging between 0.4 ± 0.1 ka and 271.8 ± 24.5 ka. Previous studies next to the study area indicate a depositional age of 1.5-2 Mio years for the oldest generation of alluvial fans, which might still be supported by our ongoing 10Be dating. Due to field observations, sediment provenance, stratigraphic characteristics and the geomorphic pattern of erosion, seven (/eight) generations of alluvial fan deposits were recognized. Comparing my ages with global glaciation cycles as well as linking them to temperature proxies retrieved from a lake on the Altiplano Plateau, a good fit between alluvial fan accumulation phases and global glacial periods (corresponding to cold/wet phases within the central Andes) is observed. This suggests that aggradation occurs during the early stages of glacial periods, while incision is expected at the end of glacial phases. This pattern might be linked to variations in the vegetational cover (controlled by water availability), which will decrease/increase during hot and dry/cold and wet interglacial/glacial phases favoring/limiting sediment production and will increase/decrease during cold and wet/hot and dry glacial/interglacial phases. Even though the eastern Andean margin is showing neotectonic activities and is assumed to be active up to recent times, deformation and seismicity might most probably have played only a minor role in relation to the rather short timescale reflected by the data.
In this cartography, I examine M.K. Gandhi’s practice of fasting for political purposes from a specifically aesthetic perspective. In other words, to foreground their dramatic qualities, how they in their expressive repetition, patterning and stylization produced a/effected heightened forms of emotions. To carry out this task, I follow the theater scholar Erika Fischer-Lichte’s features that give name to her book Äesthetik des Performativen (2004). The cartography is framed in a philosophical presentation of Gandhi’s discourse as well as of his historical sources. Moreover, as a second frame, I historicize the fasts, by means of a typology and teleology in context.
The historically and discoursively framed cartography maps four main dimensions that define the aesthetics of the performative: mediality, materiality, semioticity and aestheticity. The first part analyses the medial platforms in which the fasts as events have been historically recorded and in which they have left their traces and inscriptions. These historical sources are namely, newspapers, images, newsreels and a documentary film. Secondly, the material dimension depicts Gandhi’s corporeal condition, as well as the spatiality and temporality of the fasts. In the third place, I revise and reformulate critically Fischer-Lichte’s concepts of “presence” and “representation” with resonating concepts of G. C. Spivak and J. Rancière. This revision illustrates Gandhi’s fasts and shows the process of how an individual may become the embodiment or representation of a national body-politic. The last chapter of the cartography explores the autopoetic-feedback loop between Gandhi and the people and finishes with a comparison of the mise en scène of the hunger artists with the fasts of the Indian the politician, social reformer, and theologian. The text concludes interpreting Gandhi’s practice of fasting under the light of the concepts of “intellectual emancipation” and “de-subjectivation” of the philosopher J. Rancière.
The four main concerns of this cartography are: Firstly, in the field of Gandhi’s reception, to explore the aesthetic dimension as both alternative and complementary to the two hegemonic interpretative lenses, i.e. a hagiographic or a secular political understanding of the fasts. From a theoretical perspective, the cartography pursues to be a transdisciplinary experiment that aims at deploying concepts that have been traditionally developed, derived from and used in the field of the arts (theater, film, literature, aesthetic performance, etc.) in the field of the political. In brief, inverting an expression of Rancière, to understand politics as aesthetics. Thirdly, from a thematic point of view, the cartography inquires the historical forms of staging and perception of hunger. Last yet importantly, it is an inquiry of the practice of fasting as nonviolence, what Gandhi, its most sophisticated modern theoretician and practitioner considered its most radical expression.