Jürgen Herget's research while affiliated with University of Bonn and other places

... Despite the degree of consilience between field and flume, field exposures of stratification are largely restricted to isolated, narrow, vertical sections that are inadequate to develop a 3D appreciation of bar stratigraphy (Baker et al., 2022;Carling, 2013). Thus, there are no 3D stratigraphic models which represent the form of the stratification throughout a natural bar (Baker et al., 2022). ...

... In the past few decades, a great deal of research has been conducted to investigate how the habitat strengthening structure affects the flow field and the accumulation of the aquatic organisms. The following only discusses the research about boulder and boulder cluster, and the large roughness elements in streams and rivers are usually modeled as spheres, hemispheres, cylinders, hemispherical cylinder, and rectangular prisms (Shamloo et al. 2001;Shinneeb and Balachandar 2016;Euler et al. 2017;Schlömer et al. 2021). When water flows through obstacles, the flow cross section is narrowed, the flow on both sides accelerates, and the flow velocity upstream of the obstacle decreases significantly (Tritico and Hotchkiss 2005;Baki et al. 2014Baki et al. , 2015. ...

... In the absence of these types of data, the reconstruction of older flood levels relies on historical or geological data (Benito et al., 2004). Combining documentary and sedimentary records reduces the uncertainties associated with each approach (Sheffer et al., 2003;Thorndycraft et al., 2006;Schulte et al., 2019;Herget, 2020). ...

... As a result, the thesis as a whole as well as some of the individual chapters combine physical geography and geology with archaeology and historical geography to answer an ultimately hydrological question. Multidisciplinarity is increasingly being recognized as very important in palaeoflood hydrological research (Woodward et al., 2010;Fontana et al., 2020a), and this thesis underlines that idea. ...

... 2 of 14 embedded into the bed would not affect the surface flow whereas rocks protruding would, in turn changing interfacial processes (Ryel et al., 2002;Schlömer et al., 2020;Wright-Stow et al., 2006). We used a protrusion ratio, which is defined as the height of the protruding portion to the total height of the cobble, to quantify how much the cobble is protruded from the bed. ...

... A range of radiogenic dating methods (cosmogenic 10 Be, 14 С, Thermoluminescence, Optically Stimulated Luminescence (OSL)) have provided dates in the range 12-26 ka for megaflood-related sediments. These include: deposits in glacier-and moraine-dammed lakes in the Kurai Basin and surroundings; large blocks on the surfaces of postmegaflood terraces in the Katun Valley and in the bottom of the Kurai Basin; and loess overlying megaflood deposit (Lehmkuhl et al., 2007;Reuther et al., 2006;Panin et al., 2015c;Zolnikov et al., 2016;Deev et al., 2019;Agatova et al., 2020;Herget et al., 2020). However, 14 C and OSL dates for features in the Chuya and Katun valleys, their tributaries, and in the Uimon Basin, indicate ages in the range of 40-100 ka. ...

... In the most recent two decades research in the field of historical climatology has made a significant advance in our knowledge of how societies functioned in the past, and how they dealt with climate variability throughout the centuries (Brázdil et al., 2013a(Brázdil et al., , b, 2018Camenisch et al., 2016Camenisch et al., , 2020Kiss, 2014Kiss, , 2017Kiss, , 2019Kiss and Nikolić, 2015;Kiss and Pribyl, 2019;Huhtamaa and Helama, 2017;Ljungqvist et al., 2021). However, much still remains to be done. ...

... This type of evidence typically only persists for weeks, in humid climates, to several years, in semiarid and arid climates (Williams and Costa, 1988). In contrast, paleostage indicators provide longer lasting evidence of peak flow stages, and typically consist of fine-textured flood sediment (slack-water flood deposits; e.g., Fig. 2C), gravel and boulder bars, silt lines, and erosion features (Herget, 2020;Kochel and Baker, 1988;Koenig et al., 2016), as well as durable botanical evidence such as scars on riparian trees (McCord, 1996). Depending on the environment, such evidence can persist for several millennia . ...

... Dry periods, droughts, mega-droughts, and their societal impact are a relatively new topic of climate history (overview and state of the art: Brázdil et al., 2019). Research on premodern droughts in Europe has focused on extremes like the infamous 1540 drought (Wetter and Pfister, 2013;Wetter et al., 2014) and its connection to peaks in the numbers of city fires (Zwierlein, 2011) as a reliable indicator of dry conditions. But drought is also a topic traceable in the documentation of Southeast Asia (Adamson and Nash, 2018, p. 205), Central/South America in pre-and post-Columbian times (Del Rosario Prieto and Roja, 2018, p. 216), and North America (White, 2019). ...

... In the past few decades, a great deal of research has been conducted to investigate how the habitat strengthening structure affects the flow field and the accumulation of the aquatic organisms. The following only discusses the research about boulder and boulder cluster, and the large roughness elements in streams and rivers are usually modeled as spheres, hemispheres, cylinders, hemispherical cylinder, and rectangular prisms (Shamloo et al. 2001;Shinneeb and Balachandar 2016;Euler et al. 2017;Schlömer et al. 2021). When water flows through obstacles, the flow cross section is narrowed, the flow on both sides accelerates, and the flow velocity upstream of the obstacle decreases significantly (Tritico and Hotchkiss 2005;Baki et al. 2014Baki et al. , 2015. ...