20,855 research outputs found
Sustainability, collapse and oscillations in a simple World-Earth model
No full textThe Anthropocene is characterized by close interdependencies between the natural Earth system and the global human society, posing novel challenges to model development. Here we present a conceptual model describing the long-term co-evolution of natural and socio-economic subsystems of Earth. While the climate is represented via a global carbon cycle, we use economic concepts to model socio-metabolic flows of biomass and fossil fuels between nature and society. A well-being-dependent parametrization of fertility and mortality governs human population dynamics. Our analysis focuses on assessing possible asymptotic states of the Earth system for a qualitative understanding of its complex dynamics rather than quantitative predictions. Low dimension and simple equations enable a parameter-space analysis allowing us to identify preconditions of several asymptotic states and hence fates of humanity and planet. These include a sustainable co-evolution of nature and society, a global collapse and everlasting oscillations. We consider different scenarios corresponding to different socio-cultural stages of human history. The necessity of accounting for the ‘human factor’ in Earth system models is highlighted by the finding that carbon stocks during the past centuries evolved opposing to what would ‘naturally’ be expected on a planet without humans. The intensity of biomass use and the contribution of ecosystem services to human well-being are found to be crucial determinants of the asymptotic state in a (pre-industrial) biomass-only scenario without capital accumulation. The capitalistic, fossil-based scenario reveals that trajectories with fundamentally different asymptotic states might still be almost indistinguishable during even a centuries-long transient phase. Given current human population levels, our study also supports the claim that besides reducing the global demand for energy, only the extensive use of renewable energies may pave the way into a sustainable future.Open-Access-Publikationsfonds 201
How temperature seasonality drives interglacial permafrost dynamics: implications for paleo reconstructions and future thaw trajectories
No full textAbstract. Various proxy records have suggested widespread permafrost degradation in northern high latitudes during interglacial warm climates, including the mid Holocene (MH, 6000 years before present) and the last interglacial (LIG, 127 ka BP), and linked this to substantially warmer high-latitude climates compared to the pre-industrial period (PI). However, most Earth system models suggest only modest warming or even slight cooling in terms of annual mean surface temperatures during these interglacials, seemingly contradicting the reconstructions of widespread permafrost degradation. Here, we combine paleo climate simulations of the Alfred Wegener Institute's Earth system model version 2.5 (AWI-ESM-2.5) with the CryoGridLite permafrost model to investigate the ground thermal regime and freeze-thaw dynamics in northern high-latitude land areas during the MH and the LIG in comparison to the PI. Specifically, we decompose how the annual mean and seasonal amplitude (that is, the difference between the maximum and minimum monthly mean) of surface temperatures affect the occurrence of permafrost, seasonal frost, thaw depth and duration, and thermal contraction cracking activity. For the MH (LIG) AWI-ESM-2.5 simulated global-mean surface temperatures in the simulation domain to be about 0.1 K lower (0.4 K higher), and the global-mean seasonal amplitudes to be 2.9 K (7.4 K) higher than for the PI. With respect to interglacial permafrost characteristics, our simulations revealed that (i) local permafrost probabilities and global permafrost extent are predominantly determined by mean temperatures, (ii) maximum thaw depths are increasing with both annual mean and seasonal amplitudes, and (iii) thermal contraction cracking within the permafrost domain is almost solely driven by the seasonal amplitudes of surface temperatures. Thus, not only mean warming, but also the enhanced seasonal temperature amplitude due to a different orbital forcing have driven permafrost and ground ice dynamics during past interglacial climates. Our results provide an additional explanation of reconstructed periods of marked permafrost degradation in the past, which was driven by deep surficial thaw during summer, while colder winters allowed for permafrost persistence in greater depths. Our results further suggest that past interglacial climates have limited suitability as analogues for future permafrost thaw trajectories, as rising mean temperatures paralleled by decreasing seasonal amplitudes expose the northern permafrost region to magnitudes of thaw that are likely unprecedented since at least Marine Isotope Stage 11c (about 400 ka BP)
Jan Kapr's contribution to contemporary music : an essay about a composer and teacher
No full textThis creative project is a treatise on a leading personality of Czechoslovakian musical life, the composer, Jan Kapr. The author discusses the following:1. The complicated development of Kapr's career and work, 2. Kapr's method of organization of musical material in a composition, as described in his book Constants,3. His former and current style which is demonstrated in two of his compositions, Concert Variations, for flute and string orchestra and Testimonies for four solo instruments,4. Two of his recent works, Exercises for Gydli and the Symphony No. 7, Country of Childhood.Thesis (M.A.
Measurements in soil and air at Samoylov Station (2002-2018), version 201908
No full textThis data set includes meteorological, soil, permafrost data obtained from the long term observational site Samoylov, located in the Lena River Delta, Siberia, between 1998 to 2018. The instrumentation, calibration, proccessing and data quality control is explained in Boike et al. (2018).
The mean annual air temperature 1998–2017 was calculated as -12.3 °C, but includes years with missing data (1998, 2000–2003, 2005, 2006, 2009, 2010). Including only years with full data records (1999, 2004, 2007-2017), the mean annual air temperature is -11.7 °C. Similarly, the mean monthly temperatures of the warmest month (July) is computed as 9.4 °C (average of years 1999, 2004, 2005, 2007, 2008, 2011-2017) and for the coldest month (February) -31.7 °C (average of months of 1999, 2000, 2004, 2005, 2007, 2008, 2011-2017). The average summer rainfall (June-October) was 145.2 mm (average of years 1999, 2003–2008, 2011-2017).
This is a new version of dataset:
Boike, Julia; Nitzbon, Jan; Anders, Katharina; Grigoriev, Mikhail N; Bolshiyanov, Dimitry Yu; Langer, Moritz; Lange, Stephan; Bornemann, Niko; Morgenstern, Anne; Schreiber, Peter; Wille, Christian; Chadburn, Sarah; Gouttevin, Isabelle; Kutzbach, Lars (2018): Measurements in soil and air at Samoylov Station (2002-2018). PANGAEA, https://doi.org/10.1594/PANGAEA.891142
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
ELEVEN FACES OF JAN GOGOL, JR.
No full textAuthor Jan Rendl in his thesis attempts to look at the world of ideas and educator Jan
Gogola ml. through the eleven chapters in which each chapter somehow characterizes itself by Jan Gogola ml. and each of them somehow determines its creative ideas of it through the metaphor of a football match when Jan Gogola, with its characters, movies himself a teammate, as well as defensively. It gives goals with their situations as well as occasionally digging his opponents ankles.
Jan Gogola ml. thus embodies one stage of the Department of Documentary Film at FAMU, which often stands at the intersection between teaching activities and Karel Vachek among students who applied by them during their seminars psychological methods that work must be peculiarly associated with the author of the film
Dr. Jan French – Faculty Author Interview
No full textDr. Jan French, Assistant Professor of Anthropology, discusses her new book, Legalizing Identities: Becoming Black or Indian in Brazil’s Northeast, which shows how law can successfully serve as the impetus for the transformation of cultural practices and collective identity
Jan Bernátek - organ works
No full textThis graduation thesis provides a more detailed view on compositoins of Jan Bernátek.The aim is to present this less well-known temporary czech author,who makes use of the organ in the majority of his work
The Theological Work of Jan Valerián Jirsík
Full text linkAnglická anotace The theological work of Jan Valerian Jirsík Jan Hamberger This thesis deals with the theological work of the Czech 19th century author Jan Valerián Jirsík (1798-1883). Its first part consists of an introduction into the Czech historical context of the 19th century and the life of the author. Its second part presents a survey of the literary-theological work of Jirsík in three life phases: the first phase is demarked by his activity as chaplain and vicar, the second phase by his editorial activity for Casopis pro katolické duchovenstvo (trans. Magazine for catholic clergy) and the last phase by his pontifical years in the diocese of Southern Bohemia. His literary work is divided by theme into various periods, shortly described and characterized. The last and major section of this thesis deals with the most comprehensive and renown work of Jan Valerián Jirsík - Populární dogmatika (trans. Popular doctrine). This pivotal work of theologian Jirsík is discussed at large and analyzed by tractate, both apologetic and dogmatic. The conclusion expresses the prevailing character of the entire work of Jirsík and its significance. Key words: Theology Apologetic theology Dogmatic theology Theological literature Catholic Churc
Actor Profile of Jan Vondracek
No full textDivided into seven chapters, the work treats seven roles of the Czech actor Jan Vondracek (born in 1966) in Divadlo v Dlouhe Theatre from 1997-2008. The author starts from the analysis of Vondracek's performances and describes the specifics of his
showmanship and generalizes the personality traits of his characters. She also ponders the meaning of Czech dramatic art based on
typical characters in the context of contemporary Czech theatre
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