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Glacier melt is an essential source of freshwater for the arid regions surrounding the Tian Shan. However, the knowledge about glacier volume and mass changes over the last decades is limited. In the present study, glacier area, glacier dynamics and mass changes are investigated for the period ~1975–2007 for Southern Inylchek Glacier (SIG) and Northern Inylchek Glacier (NIG), the largest glacier system in Central Tian Shan separated by the regularly draining Lake Merzbacher. The area of NIG increased by 2.0 ± 0.1 km2 (~1.3%) in the period ~1975–2007. In contrast, SIG has shrunk continuously in all investigated periods since ~1975. Velocities of SIG in the central part of the ablation region reached ~100–120 m a−1 in 2002/2003, which was slightly higher than the average velocity in 2010/2011. The central part of SIG flows mainly towards Lake Merzbacher rather than towards its terminus. The measured velocities at the distal part of the terminus downstream of Lake Merzbacher were below the uncertainty, indicating very low flow with even stagnant parts. Geodetic glacier mass balances have been calculated using multi-temporal digital elevation models from KH-9 Hexagon (representing the year 1975), SRTM3 (1999), ALOS PRISM (2006) and SPOT-5 high-resolution geometrical (HRG) data (2007). In general, a continuous mass loss for both SIG and NIG could be observed between ~1975 and 2007. SIG lost mass at a rate of 0.43 ± 0.10 m w.e. a−1 and NIG at a rate of 0.25 ± 0.10 m w.e. a−1 within the period ~1975–1999. For the period 1999–2007, the highest mass loss of 0.57 ± 0.46 m w.e. a−1 was found for NIG, whilst SIG showed a potential moderate mass loss of 0.28 ± 0.46 m w.e. a−1. Both glaciers showed a small retreat during this period. Between ~1975 and 1999, we identified a thickening at the front of NIG with a maximum surface elevation increase of about 150 m as a consequence of a surge event. In contrast significant thinning (>0.5 m a−1) and comparatively high velocities close to the dam of Lake Merzbacher were observed for SIG, indicating that Lake Merzbacher enhances glacier mass loss.

Long-term monitoring of water resources and climate parameters at the scale of river basins requires networks of continuously operated in-situ stations. Since 2009, GFZ and CAIAG, in cooperation with the National Hydrometeorological Services (NHMS) of Central Asia, are establishing such a regional monitoring network in Kazakhstan, Kyrgyzstan, Tajikistan, Uzbekistan, and lately Afghanistan to collect observations of meteorological and hydrological parameters and to deliver them to the end-users for operational tasks and scientific studies. The newly developed and installed remotely operated multi-parameter stations (ROMPS) do not only monitor standard meteorological and hydrological parameters, but also deliver Global Navigation Satellite System (GNSS) data for atmospheric sounding as well as tectonic studies. Additionally, three stations integrate seismic sensors for earthquake monitoring. The observational data from the ROMPS is transmitted nominally in near-real time, but at least once a day to a centralized geo-database infrastructure for long-term storage and data redistribution. Users can access the data manually using a web-interface or automatically using SOS requests; in addition, data is planed to be distributed to the NHMS through standard communication and data exchange channels.

Long-term monitoring of water resources and climate parameters at the scale of river basins requires networks of continuously operated in-situ stations. Since 2009, GFZ and CAIAG, in cooperation with the National Hydrometeorological Services (NHMS), are establishing such a regional monitoring network in Central Asia (Kazakhstan, Kyrgyzstan, Tajikistan, Uzbekistan, and Afghanistan) which is collecting observations of meteorological and hydrological parameters and delivering them to the end-users. The network design focuses mainly on the higher elevations where the recent decline of monitoring stations and networks established in Soviet times was strongest, and the resulting observational gap hinders research on climate and hydrological change as well as operational tasks in water management such as the seasonal runoff forecast. The newly developed and installed Remotely Operated Multi-Parameter Stations (ROMPS) do not only monitor standard meteorological and hydrological parameters, but also deliver GPS data for atmospheric sounding as well as tectonic studies. The observational data from the ROMPS is transmitted at least once a day to a centralized geo-database infrastructure for long-term storage and data redistribution. Users can access the data manually using a web-interface or automatically using SOS requests; in addition, data is distributed to the NHMS through standard communication and data exchange channels.

The northeast Ethiopian plateau is composed of a low-grade metamorphic complex which includes the Tsaliet Metavolcanics overlain by the NE-trending upright folded metasediments of the Tambien Group including a thick stromatolitic carbonate sequence. High-grade metasediments and orthogneisses structurally underlie this unit in the Red Sea Lowlands of east Eritrea. In east Eritrea, the low-grade Bizen Domain metasediments and metavolcanics structurally overlie the Ghedem Domain high-grade rocks with a subhorizontal moderately W-dipping transition zone of tectonic origin. Field studies augmented by remote sensing analysis of Modular Optoelectronic Multispectral Stereo Scanner on Priroda (MOMS-2P) images are used to outline the structure, stratigraphy and geomorphology and the continuation of the Negash Synclinorium with adjacent structures up to the Bizen Domain in east Eritrea. The protolith age of the low- and high-grade rocks is around 850 and 800 Ma, respectively. Peak metamorphic conditions in the high-grade metasediments reached 700 ◦ C and up to 12 kbar (depth of ∼40 km) at ∼650 Ma. This indicates that an elevated mountain belt with a very thick crust existed in Eritrea during the evolution of the East African Orogen (EAO). Rapid exhumation of the high-grade metamorphic rocks occurred between 640 and 545 Ma involving extension along a tectonic transition zone. The transition zone is a ductile detachment overprinted by brittle low-angle faulting. Although partly pertaining to a Tertiary deformation related to the opening of the Red Sea, we suggest that this low-angle zone was a detachment surface in the Neoproterozoic that accommodated extension during orogenic collapse to restore normal crustal thickness which was thickened due to collision between East and West Gondwana. The sedimentary rocks of the Tambien Group in north Ethiopia and the Bizen Domain in east Eritrea (stromatolitic limestone, stromatolitic dolostone, polymict conglomerate-diamictites), their stratigraphy and age of deposition suggest association with “Snowball Earth”. Light δ 13 C( −6.74 and −6.88‰) were measured for the stromatolitic dolostone and algal mat of the Bizen Domain which are characteristic for cap-carbonates associated with Snowball Earth. © 2003 Elsevier Science B.V. All rights reserved.