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The Regional Research Network „Water in Central Asia“ (CAWa) funded by the German Federal Foreign Office consists of 18 remotely operated multi-parameter stations (ROMPS) in Central Asia. These stations were installed by the German Research Centre for Geosciences (GFZ) in Potsdam, Germany in close cooperation with the Central-Asian Institute for Applied Geosciences (CAIAG) in Bishkek, Kyrgyzstan, the national hydrometeorological services in Uzbekistan and Tajikistan, the Ulugh Beg Astronomical Institute in Tashkent, Uzbekistan, and the Kabul Polytechnic University, Afghanistan. The primary objective of these stations is to support the establishment of a reliable data basis of meteorological and hydrological data especially in remote areas with extreme climate conditions in Central Asia for applications in climate and water monitoring. Up to now ten years of data are provided for an area of scarce station distribution and with limited open access data which can be used for a wide range of scientific or engineering applications. he data described in this manuscript will be made publicly available with the DOI https://doi.org/10.5880/GFZ.1.2.2020.002 (Zech et al., 2020) after final acceptance. In the meantime, find data via this temporary link: https://dataservices.gfz-potsdam.de/panmetaworks/review/084165424ac07f9ccb5391ab452e4dc9fff92076e265ee8bc86acc90a6ea287b/ or via the Sensor Data Storage System (SDSS) at http://sdss.caiag.kg. [ABSTRACT FROM AUTHOR]

During the past two centuries, several large earthquakes have caused extensive damages in the city of Almaty in Kazakhstan. Increasing the preparedness for future events, the definition of the optimal engineering designs for civil structures and the corresponding mitigation of earthquake risks involves the accomplishment of site response studies. To this regard, a temporary seismological network of 15 stations was installed in the city aiming at the accurate identification of local variations of site response at different locations. As the city is settled on a deep sediment-filled plain with laterally strongly varying thicknesses, bound to the south by the Tien-Shan mountain range, the city might face important site effects: large amplification and significant increase of shaking duration. In addition, surface waves in the low-frequency range around and slightly higher than the fundamental resonance frequency, which could be generated at the boundaries of the basin, can carry a large amount of energy. In turn, this will influence both the spatial distribution of the level of amplification and the temporal lengthening of ground motion significantly. For quantifying these effects, we apply complex trace analysis, which uses the instantaneous polarization characteristics of the seismic signal for separating waves arriving at a single site from different directions. In this way, secondary surface waves originating at various sites along the edge of the Almaty basin can be identified as well as their generation regions. After having assessed 1-D amplification effects with wellestablished techniques like the standard spectral ratio and the horizontal-to-vertical spectral ratio techniques, the results further indicate that thick layers of soft clay deposits and the 3-D structure of the basin give rise to lengthening of ground motion and high amplification values at low frequencies around 0.2 Hz. The steep structure of the sediment--bedrock interface at the southern edge of the Almaty basin can generate surface waves with distinct azimuths, meaning that the spatial variability of ground motion is not only related to a simple 1-D response but it can be strongly modified by secondary waves generated at the margin of the basin. [ABSTRACT FROM AUTHOR]

In this study, the joint deconvolution is applied to recordings of three test cases located in the cities of Bishkek, Kyrgyzstan, Istanbul, Turkey, and Mexico City, Mexico. Each test case consists of a building equipped with sensors and a nearby borehole installation in order to investigate different cases of coupling (impedance contrasts) between the building and the soil by analyzing the wave propagation through the building-soil-layers, and hence resolving the soil-structure-interactions. The three installations considering different dynamic characteristics of buildings and soil, and thus, different building-soil couplings, are investigated. The seismic input (i.e., the part of the wave field containing only the up-going waves after removing all down-going waves) and the part of the wave field that is associated with the waves radiated back from the building are separated by using the constrained deconvolution. The energy being radiated back from the building to the soil has been estimated for the three test cases. The values obtained show that even at great depths (and therefore distances), the amount of wave field radiated back by the building to the soil is significant (e.g., for the Bishkek case, at 145 m depth, 10% of the estimated real input energy is expected to be emitted back from the building; for Istanbul at 50 m depth, the value is also 10-15% of the estimated real input energy while for Mexico City at 45 m depth, it is 25-65% of the estimated real input energy). Such results confirm the active role of buildings in shaping the wave field. [ABSTRACT FROM AUTHOR]

The 2009 expedition led to the Inylchek Glacier in eastern Kyrgyzstan, the largest glacier of the Tien Shan with a length of 60,5 kilometers. In this paper we present the results of our investigations in the surroundings of the Northern Inylchek Glacier, namely in the Peremitschka, the seasonally flooded plain situated between the Southern Inylchek Glacier and Upper Lake Merzbacher. During the summer, this plain is flooded by melt water discharged from the Northern Inylchek Valley, creating the up to 120 m deep Lower Lake Merzbacher, which regularly bursts out and releases its water through an englacial piping system of the Southern Inylchek Glacier in. It is due to this unique phenomenon that Lower Lake Merzbacher has been the subject of study by scientists on numerous expeditions during the last century. As a mapping basis for our field works, we used an enlarged scene acquired in September 2005 from the Quickbird satellite with 60 cm ground resolution. For identification of advancing and retreating parts of the Inylchek Glacier system, a pan-sharpened Landsat 7 ETM+ scene (bands 1, 4 and 7) with a ground resolution of 15 m acquired in 2006 was used. A time series analysis of aerial photos dating from 1943 and 1956 was compared to the Quickbird scene from 2005 and revealed first the retreat and later the rapid advance of the Northern Inylchek Glacier along a distance of at least two kilometres. Since neither indications of a glacier lake outburst around Upper Lake Merzbacher nor stretched ogives or erosional scars in the Northern Inylchek Glacier implying a rapid surge could be detected, the mechanism of this fluctuating glacier is subject to ongoing investigations. Our helicopter-supported campaign in the Peremitschka at altitudes between 3300 and 3500 meters lasted only four days. For the glaciogeologic and geomorphologic interpretation of remote sensing imageries we used geophysical methods such as electric resistivity tomography (ERT) and frequency domain electromagnetics (FDEM). The 800 m long ERT-profile crossing the Peremitschka plain revealed resistivities ranging from 6 Ohmmeter (ohm.m) in the near subsurface to 100.000 ohm.m down to a depth of 45 meters. A series of thin, undulated, low-resistivity layers are underlain by a thick high-resistivity layer, which has been interpreted as dead ice from the formerly advancing Northern Inylchek Glacier. A small river flows down the Northern Inylchek Valley, here termed "Merz Rivulet" or "Merzbach", with a flow of about 30 m³/second. Along its course it has locally eroded the Peremitschka plain to a depth of 20-25 meters. This steep slope within the Peremitschka reveals an intercalation of silty calcareous lake deposits with ice layers and ice lenses respectively. These outcrops have been interpreted as near subsurface permafrost layers, which can be correlated with the undulated low-resistivity layer of the ERT-profile. Additionally, high resolution mapping of this permafrost zone using frequency domain electromagnetics with 2525 Hertz (Hz) and 5025 Hz revealed cone-like depressions, which were interpreted as glacier karst. [ABSTRACT FROM AUTHOR]