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The climatic conditions are changing and showing their impact on the glaciers. The melting of glaciers is amplified in the recent past and in the present time due to increased global warming. Consequently, the hazardous events of glacial lake outburst floods (GLOFs) are posing a serious threat to the population in the Himalayan region. Many events of GLOFs have caused a huge loss of life and property in the downstream mountain regions. Therefore, there is an essential requirement of developing an effective early warning system to alert masses before any disastrous incident. In this paper, we reviewed the studies related to the GLOF events in the Indian and surrounding Himalayan region. Our main aim for this study is to emphasize the need for an early warning system and in this connection, we are proposing the wireless sensor network (WSN) based system. In the present time, the WSN based early warning systems are gaining popularity in the domain of different natural hazards due to their low cost of installation, maintenance and capability of real-time monitoring. For that reason, these kinds of early warning systems can be installed at multi-locations in a planned manner. This will help authorities for forming mitigation and executions plans as well as downstream people will be attentive regarding any unfortunate GLOF related catastrophe. [ABSTRACT FROM AUTHOR]

This research paper compares the result of Object based and Pixel based classification techniques for glacier change detection on Landsat Thematic mapper (TM) and Enhanced Thematic Mapper (ETM+) imageries. The objective of this study is to see which classification method performs better for change detection in mountainous regions. Northern face of Himalayan region, The study area is undergoing climate change in the form of rapid melting of glacial ice mass, expansion of the existing lakes and creation of new lakes. This results in Glacial Lake Outburst Flood (GLOF) and breach or outburst from ice and ‘moraine dams’ causing devastating floods downstream. The global warming phenomenon worldwide has resulted in a significant decrease in glacial cover. Glacier's change monitoring and permafrost-related hazards have long been studied using remote sensing data and techniques to assess the damage. The world is facing a serious problem of handling the climate change issue and its effects on humans as well as on natural resources. Glaciers are considered as one of the best indicators of climate change [1]. Landsat TM/ETM+ images were used for glacier change monitoring of Turkey's mountains project, Mount Suphan. The results show that about ¾ of total area of suphan glacier has been lost in 23 years. Traditional image classification methods use only the spectral information at pixel level without considering the shape of underlying objects [2]. However, object-based image classification process uses spectral and spatial dimensions (shape of feature) in order to perform classification. In this study, multi temporal Landsat TM and ETM+ image from 1990 to 2010 have been used. Initially, the traditional pixel-based classification was performed on Landsat thematic layers and layers developed from indices like NDVI and NDSII. Then object-based classification of these images was carried out. The comparison of the classification results (both qualitative and quantitative) show that the object-based approach gives about 10–15% higher accuracy, much better results in terms of area estimation and change detection of snow covered areas as compared to traditional pixel-based classification. The results also indicate that object based classification is more useful in mountainous regions to avoid confusion among classes produced by shadows. [ABSTRACT FROM PUBLISHER]

The Third-Day Road Log consists of two ~2-hour stops at Gilman Tunnels and Soda Dam. We drive from San Ysidro into the Jemez Mountains along State Road 4. From San Ysidro, we follow the Jemez River past Jemez Pueblo, turn left on State Road 485, drive to Gilman Tunnels, then back to State Road 4, and make a left to Soda Dam. The goals of this field trip are to look at the oldest and youngest rocks in the Nacimiento nexus area. Stop 1 will discuss the Proterozoic basement of the Nacimiento Mountains uplift exposed in a fault block in the rugged Guadalupe Box of the Guadalupe River near Gilman Tunnels (Fig. 3.1). Stop 2 will discuss Quaternary travertine at Soda Dam, including rocks that are still forming today. An optional stop along the route that could be done on a longer trip is the Jemez Springs Bath House to view geothermal waters. [ABSTRACT FROM AUTHOR]

Available results for five studied valleys of the Khibiny Mountains, Kola Peninsula, suggest that slush flows and, possibly for some valleys, typical debris flows with lower frequency, are a leading mechanism for downstream sediment delivery and valley floor topographical formation. Typical fluvial topography in slush flow-affected basins is extremely suppressed or nonexistent, since under such conditions, stream channels are unable to rework slush flow deposits. The recovery phase of fluvial topography can serve as an indicator of the magnitude and time passed since the last extreme event. A combination of grain size analysis, radionuclide fingerprinting with the 232Th content in the finer-grained sediment matrix (size <10 mm) and 14C dating, were applied to reveal the age and common structure of debris and slush flow environments and to investigate the main factors in their lithodynamics. Those helped to estimate transportation distances and capacities of the flows and the amount of fluvial reworking of its deposits with time. Application of radiocarbon dating to determine absolute ages (about 30 dates) of stabilization periods for the colluvial cones, mountain fans and valley bottoms and integration with other available chronological data provided a basis for distinguishing several stages of decreased activity of debris and slush flows and extreme slope failures through the second half of the Holocene. Field mapping and remote sensing data interpretation revealed spatial distribution patterns of debris and slush flows. Geomorphic analysis of large relic landforms in valley bottoms confirms, in general, the case for a significant reduction of debris flow magnitude since the last deglaciation and distinct shift to slush flow processes with much lower clastic content. A reliable chronology of the early events is yet to be obtained representing a challenging problem for future research. [ABSTRACT FROM AUTHOR]

After the regression of mountain glaciers, the typical forms of morainic lake basins were created in morainic deposits at the bottoms of the Tatras valleys. During some period they were filled by alpine lakes. During Holocene, a lot of lake basins were deformed by geomorphological processes. Frequently the lakes in them disappeared. Nowadays, it is possible to identify them by precise DTM of relief despite long time interval. In this article, we reconstruct defunct alpine lake in Zelené pleso valley, its hypothetical lake basin morphology, volume, area and altitude of the water. The reconstruction will be made by basic identification of a dry lake basin and analysis of a precise DTM. We simulate typical palaeo form of the relief. On the basis of the actual and simulated DTM we also bring the information about the volume of sediments that were taken away by erosive processes from the morainic dam of former lake during Holocene. [ABSTRACT FROM AUTHOR]

We discuss 150 MHz GPR profiles of glacial till, reworked till, colluvium or decaying granite, which mainly contain random inclusions related to lithology, grain size, or water. The profiles contain numerous diffractions and limited stratification to possibly more than 40 m depth. The penetration, lack of dispersion, and lack of well developed asymptotes that originate from diffractions at depth suggest that volume scattering is present, but not a significant source of signal loss. The deep penetration may result from enhanced backscatter, by which rays propagating in opposite directions along the same and least lossy round trip path interfere constructively. [ABSTRACT FROM PUBLISHER]