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Predicting the occurrence and spatial patterns of rainfall induced flash floods is still a challenge. Instant genesis and typically smaller areal coverage of the flash floods are the major impediments to their forecasting. Analysis of the morphometric parameters provides useful insight on hydrological response of the drainage basins to high intensity rainfall events. This information is valuable for understanding the flash flood potential of the drainage basins and for evading the destructions caused by the hazard. Here, we use eighteen morphometric parameters that influence the runoff volume, flow velocity, and inundation depth scenario of a flash flood. The analysis has been carried out for simulating the relative flash flood susceptibility of thirteen watersheds (B1 to B13) of variable sizes in southeastern Bangladesh. The morphometric parameters were derived from Digital Elevation Model (DEM) using Geographic Information System (GIS). The evaluated basin parameters include: area (A), perimeter (P), length (Lb), stream order (Su), stream number (Nu), stream length (Lu), stream frequency (Fs), drainage density (Dd), texture ratio (Rt), bifurcation ratio (Rb), basin relief (Hr), relief ratio (Rr), ruggedness number (Rn), time of concentration (Tc), infiltration number (If), and form factor (F). Two relative flash flood susceptibility scenarios were generated: (i) general watershed level, and (ii) more precise pixel level status. The watershed level comparison reveals that B4 and B6 watersheds constituting 72.61% of the total area are 'very high' susceptible, whereas the susceptibility of the other watersheds has been found as 'high' [B5 (6.95%)], 'moderate' [B8 and B13 (8.63%)], 'low' [B2, B10, B11 (4.64%)], and 'very low' [B1, B3, B7, B9, and B12 (7.18%)]. The derived watershed susceptibility map was subsequently integrated with two spatial analysis algorithms i.e., topographic wetness index (TWI) and topographic position index (TPI) through overlay analysis. The integration helped to understand the combined role of the general watershed morphometry and the in situ topography for determining the flash flood susceptibility of each spot (30 m × 30 m) within all the selected watersheds. The quantitative analysis and characterization of the watersheds from the perspective of flash flood hazard in this investigation is expected to be useful for implementing the site-specific mitigation measures and alleviating the effects of the hydrological hazard in the study area. [ABSTRACT FROM AUTHOR]

This study aims to carry out the flood frequency analysis (FFA) of river Jhelum in Kashmir basin. Gumbel and Log-Pearson Type III (LP3) probability distributions were employed for simulating the future flood discharge scenarios using annual peak flow data (1956–2014) from three gauging stations of the River Jhelum. The predicted design floods of various return periods (Tr) i.e., 5, 10, 25, 50, 100, and 200 were obtained and compared. The findings reveal that the estimated discharge of all the return periods exceeds the current average carrying capacity (∼35000 cusecs in Srinagar) of the river. It is thus likely that any flood event with the return period of five years or above would overflow the banks of the River Jhelum. Furthermore, the present study demonstrates that the river discharge can be satisfactorily projected by any one of the used probability distribution methods; however, as revealed by the goodness-of-fit test, Log-Pearson Type III was found to be the better fitted probability distribution among the two. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Facile synthesis of nanoporous azo polymers (NAPs) using metal-catalyst free polycondensations in basic medium. • NAPs have been designed to include triptycene, phorphyrin and azo units in the polymer backbone. • NAPs exhibits high surface area up to 1095 m2 g−1. • High CO 2 uptake up to 3.93 mmol g−1 at 273 K and 1 bar uptake by these NAPs. • Good CO 2 /N 2 selectivity (up to 64 at 273 K) shown by these NAPs. Abstract Two nanoporous azo polymers (NAPs) have been designed incorporating triptycene and porphyrin motifs in the polymer framework that are linked covalently by azo functional groups. NAPs are synthesized using metal-catalyst free polycondensations in basic medium. These are thermally stable, microporous (Type-I isotherms in N 2 adsorption–desorption measurements at 77 K) and have moderately high surface areas (SA BET = 1095 and 923 m2 g−1). NAPs show enhanced surface areas relative to either triptycene networks with azo-linkages or porphyrinic polymers having azo bridges. NAPs register high CO 2 uptake (upto 3.93 mmol g−1 at 1 bar and 273 K) with good CO 2 /N 2 selectivity (upto 64:1 at 273 K) for CO 2 capture from flue gas. Incorporation of CO 2 -philic porphyrin rings and N 2 -phobic azo groups results in improved CO 2 /N 2 selectivity in these triptycene based microporous polymers. Performance of NAPs as nanoporous polymer (in terms of gas sorption properties such as surface areas, low pressure gas uptake and gas selectivity) is also better than several non-triptycene/porphyrin but azo based porous organic polymers (POPs). NAPs have potential use in post-combustion CO 2 capture and sequestration technology. [ABSTRACT FROM AUTHOR]

In general the genesis of the Kashmir basin is being viewed as a result of compressional tectonics, perhaps because of the reason that the basin is located in India-Eurasia convergence zone. However, there is no work that convincingly demonstrates how existing geomorphic architecture of the Kashmir basin evolved due to thrust tectonics? With answer to many questions Alam et al., (2015) proposed an extensional model for the development of the Kashmir basin. Moreover, based on deformation styles at varied spatial scales Alam et al., (2017) also suggested the co-existence of dominant extensional and relatively feeble compressional deformations within the basin. Shah (2017) just on the basis of deliberate misinterpretations, recycling of copied text, unrealistic one dimensional cartoons, and as always not for scientific reasons expresses disagreement with Alam et al., (2017). Thus, while responding to the bafflement of Shah (2017), we throw further light on hybrid tectonic character of the Kashmir basin. [ABSTRACT FROM AUTHOR]

The present study aims to assess the tectonic activity in the Erin basin (NE Kashmir) on the basis of several relevant geomorphic indices and field observations. We use Digital Elevation Model (SRTM) and Survey of India (SoI) topographic maps in GIS environment to compute the geomorphic indices. The indices i.e., convex hypsometric curve, high hypsometric integral value (H i  > 0.5), low basin elongation ratio (Eb = 0.17), low mountain front sinuosity values (S mf  = 1.08 average), low valley floor width ratios (Vf < 1), topographic assymetric character (T < 1), uneven basin asymmetry factor (AF < 50), elongated shape (Bs > 4) suggest that the area is tectonically active. Moreover, prominent irregularities (knickpoints/knickzones) along longitudinal profile of the Erin River even in homogenous resistant lithology (Panjal trap) and anomalous stream gradient index (SL) values reflect that the Erin basin is dissected by two faults (EF-1 and EF-2) with NNW-SSE and SSW-NNE trends respectively. The results of this preliminary study further substantiate the recent GPS studies, which argue that the maximum strain is accumulating in the NE part of the Kashmir Himalaya. [ABSTRACT FROM AUTHOR]

This paper presents a new interpretation of overlapping differential deformations and likely causes of the structural heterogeneity within the Kashmir basin. Representing a prominent and distinctive strain feature in NW Himalaya, the broad geomorphic expression of the Kashmir as an elongated NW-SE trending sedimentary trough is inconsistent with general compression governing structural trend and deformation pattern of ∼2500 km long Himalayan Frontal Thrust zone. In addition to the general extensional geometry, there are prominent anomalous deformation features at varied spatial scales in the basins that imply dominance of extensional tectonics. We infer that contrary to the overall compression dominant mechanism of the Himalaya, the apparent extensional geometry of the basin connotes orogen-parallel extensional deformation (pull-apart), triggered by oblique convergence in the NW Himalaya. Moreover, we construe that the comparatively younger contractile (positive) features in form of the geomorphic convexity (push-up), accompanied by out-of-sequence reverse faulting (Balapur Fault, hereafter called as BF) within the basin which is generally believed to be associated with the uplift along NE dipping southern thrust complex (MBT/MCT), possibly resulted due to the tectonic reversal (positive inversion). The presence of the compressional features within the locally predominant extensional setting is suggestive of the basin's hybrid character—where variable tectonic regimes (earlier extension and subsequent compression) seem to be coexistent. [ABSTRACT FROM AUTHOR]

Since its inception, Kashmir Valley has been characterized by intense seismicity that has left a strong imprint on the country's landscape, heritage and traditions. In fact, its architectural heritage is largely shaped by the interrelationship of the natural with the human and of the physical with the social. Beginning with classical stone architecture during the first millennium, followed by a period of building with wood, Kashmir finally witnessed vernacular (mixed mode) architecture in the form of Taqq and Deji-i-Dewari from the last two centuries. Taqq and Dhajji-Dewari architecture reflects seismic risk reduction to earthquake threat through the use of timber-braced frame with masonry infill. Sporadic occurrence of earthquakes in Kashmir over the centuries led Kashmir society to learn that to fight earthquakes we ought to know them: how they cause damage, where they occur repeatedly and more importantly how to minimize the seismic risk. This seismic risk reduction was necessitated by available technology, resource use option and risk management strategies. Even the dialectics often reflect how the people were influenced by the seismicity of the region they lived in. [ABSTRACT FROM AUTHOR]

• A facile and green synthesis of a new triptycene based nanoporous polymer (TBHAP). • TBHAP has high SA BET (824 m2 g−1) and CO 2 uptake (145.8 mg g−1 at 273 K, 1 bar). • CO 2 /N 2 selectivity of TBHAP is reasonably high (84 measured at 273 K). • TBHAP rapidly captures cationic dye from a binary mixture of cationic/anionic dyes. • TBHAP efficiently and reversibly captures iodine (up to 1880 mg g−1). Gradual increase in CO 2 emission due to energy production from fossils fuels is a major contributor to global warming. Alternatively, "carbon free" nuclear energy generates radioactive and carcinogenic iodine vapors. Thus, the need to develop efficient sorbents for capture of CO 2 and I 2 is justified. Herein, we report a Triptycene-based-Hydroxyl-Azo-Polymer (TBHAP) derived from relatively inexpensive hydroquinone (one of the two monomers) and using water as a solvent. TBHAP is thermally stable and nanoporous with high surface area (SA BET up to 824 m2 g−1). The presence of permanent porosity (due to triptycene), π-rich cavities (from abundant arene rings) and active functional groups [phenolic−OH and azo (N N)] in the polymeric network of TBHAP makes it effective for reversible iodine (188 wt%), H 2 (8.9 mg g−1: 77 K, 1 bar) and CO 2 (145 mg/g: 273 K, 1 bar) uptake with moderately high CO 2 /N 2 selectivity (84 at 273 K). TBHAP is also an effective and selective adsorbent for toxic cationic dyes [Methylene blue (Q m = 250 mg g−1) and Rhodamine B (Q m = 588 mg g−1)] from an aqueous solution containing binary mixtures of cationic/anionic dyes. Thus, TBHAP is a versatile porous material with various applications in the domain of environmental remediation. [ABSTRACT FROM AUTHOR]

Bangladesh has a long history of devastating tropical cyclones. In view of the effects of the storms on the country, risk assessment is essential for devising the mitigation strategies at various levels. By way of bringing the conceptual structure of general risk model in practice, this work aims to examine the spatial patterns of cyclone risk in the Cox's Bazar district (I) and Rohingya refugee camps (II) located on the southeastern coast of Bangladesh. We use 14 parameters representing the hazard, exposure, and vulnerability as the components of risk. The selected parameters were analyzed and integrated though the complementary use of Analytic Hierarchy Process (AHP) and Geographic Information System (GIS) for depicting the cyclone risk situation comprehensively at both the spatial scales. The status of the cyclone risk was identified and quantified as very high (6.84%, 3.43%), high (45.78%, 27.82%), moderate (5.97%, 39.42%), low (40.62%, 28.70%), and very low (0.81%, 0.61%) for the spatial scale I and II respectively. In general, northwestern and southern peripheral areas exhibited higher risk than the central and northeastern parts of the Cox's Bazar district; and in the refugee settlements, camp number 1E, 1W, 7, and 13 revealed relatively higher levels of the risk. The results of the assessment (I) were correlated with experiential damage from the 1991 cyclone; a reasonable consistency was noticed between the simulated scenario and the observed impacts. We assume that the deliverables of this spatial analysis could be useful to stakeholders while formulating the cyclone risk mitigation policies for the region. Furthermore, this work demonstrates that the applied method would deliver reliable results if tested in other coastal environments. [ABSTRACT FROM AUTHOR]

The use of direct arylation polymerization (DArP) as a viable strategy to obtain porous organic polymers (POPs) has not been explored to its full potential. Instead, other strategies (such as conventional cross-coupling reactions) are usually employed to yield POPs that employ expensive organometallic monomers whose syntheses require multiple steps. Herein, using DArP, three fluorinated porous organic polymers (fPOPs: TFPP1 , TFPP2 and TFPP3) were obtained that represent unique examples of triptycene motif containing fluorine rich network polymers. These thermally stable polymers (T d > 400 °C with high char yields at 800 °C) are predominantly microporous with high surface areas (up to 1295 m2/g) and thus satisfy the requirement for facilitating superior adsorption of small gas molecules. The recorded CO 2 , CH 4 , and H 2 uptake capacities of fPOPs are superior than several previously reported fluorinated/non-fluorinated POPs. High CO 2 uptake capacities of fPOPs are due to the incorporation of ample triptycene motifs and polar C–F bonds in the polymeric backbone. Overall, the high thermal stability, surface area and sorption capacities demonstrated by these fluorinated polymers render them potential materials for the applications in capture of CO 2 and storage of CH 4 /H 2. Synthesis of a set of three unique triptycene based fluorinated porous organic polymers via direct C–H arylation and their efficient uptake of CO 2 , CH 4 and H 2. [Display omitted] • Unique report of three triptycene based "fluorinated" porous organic polymers. • Facile polymer syntheses from commercially available fluorinated monomers. • Polymers are microporous with high surface areas (up to 1295 m2/g). • Polymers have high thermal stabilities (T onset up to 582 °C) and (T d up to 626 °C). • Improved CO 2 uptake (upto 160 mg/g) relative to several reported fluorinated POPs. [ABSTRACT FROM AUTHOR]

Abstract: Kashmir has a long written history of 5000 years, which provides a sketchy picture of historical earthquakes. In all, we collated details of 16 earthquakes from the historical scribes. Most of the earthquakes had their epicenters outside the Kashmir Valley. The exceptions (earthquakes with epicenters within the valley), however, caused severe damage to life and properties and were associated with ground ruptures and long periods of aftershocks. Among them, only the 1885 event is adequately described. We have analyzed environmental effects of this destructive earthquake which occurred in the northwestern Kashmir Himalaya along Pir Panjal range in the early morning (5.00 a.m) of 30 May, 1885. Using archival sources followed by field work, the present attempt envisages applying the Environmental Seismic Intensity scale (ESI 2007) for a macroseismic intensity assessment of the 1885 Baramulla Earthquake. Inferences (primary and secondary) reveal that the 1885 Baramulla earthquake local intensity would have been VI–X on the ESI scale. Baramulla, the macroseismic epicenter of the earthquake, must have witnessed epicentral intensity of X on ESI scale. The intensity must have been variable, severe at Baramulla and less at Srinagar, because of the severity of damage decreased from NW to SE. [Copyright &y& Elsevier]

Coal-fired power plants are the highest contributors to global electricity generation. Flue gases from thermal power plants are rich in carbon dioxide. Thus, thermal plants also contribute substantially to the annual increase in the concentration of atmospheric CO 2 (greenhouse gas) which in turn leads to increased global warming and ocean acidification. Solutions to these problems are either capture of carbon dioxide from flue gas or exploring alternative sources of power generation such as nuclear energy. However, volatile radioactive byproducts produced in nuclear plants need to be arrested by a suitable adsorbent. Herein, for the first time, we report a triptycene-based hypercrosslinked porous polymer (TBHCP-OH) that contains CO 2 -philic groups (–OH and –N N–). It was obtained using a simple Friedel–Crafts alkylation reaction. Mesoporous TBHCP-OH has high CO 2 capture capacity (87.6 mg/g) and excellent iodine vapor uptake capacity (2600 mg/g). This iodine uptake capacity is the highest among all triptycene based polymers reported till date. This may be attributed to the ample supramolecular interactions between arene/heteroatoms (O and N in TBHCP-OH) and iodine. The facile and simple synthesis of TBHCP-OH as well as its ability to efficiently capture pollutants renders it a promising material for environmental remediation. [Display omitted] • Design of a new triptycene based monomer with active CO2-philic (–N N– and –OH) and N2-phobic (azo) groups. • Facile synthesis of a mesoporous triptycene polymer (TBHCP-OH) with azo and phenolic functionalities via knitting strategy. • TBHCP-OH shows high CO 2 uptake of 8.76 wt.% at 273 K and 1 bar pressure which is comparable with monoethanolamine. • TBHCP-OH selectively captures CO 2 over N 2 at 1 bar which improves at higher temperature [273K (23) and 298 K (28)]. • High I 2 vapor adsorption capacity of TBHCP-OH (up to 2600 mg/g) is best among triptycene based polymers. [ABSTRACT FROM AUTHOR]

Torrential rains, landslides, and seismic activity are the common factors that are causing unprecedented damage to life, property and infrastructure in Mandakini and Bhilangana basins of Garhwal Himalaya. Owing to such conditions, we demonstrate the feedback this landscape in Garhwal Himalaya in response to episodic tectonic uplift and monsoon precipitation. We calculated conventional geomorphic parameters to access the tectonic deformation across the major thrusts and faults. We further analyzed the normalized steepness index (K sn), Chi (χ), and knickpoints along the longitudinal course of rivers. Additionally, the study attributed to active nature of Chail/Ramgarh thrust along the Balganga valley as envisaged by five levels of unpaired fluvial terraces, entrenched stream course, river ponding, active and stabilized landslide deposits, etc. Moreover, the flooding during the heavy rainfall events induced river toe cutting makes an effect on settlement over fluvial deposits. Therefore, we suggested that the highly dissected and tilted basins with deep V shaped valleys and ongoing seismicity also fabricates the region more vulnerable for hazards which threaten the human lives. [ABSTRACT FROM AUTHOR]

This study aims at assessing the tectonic and climatic responses to landscape changes transpired in the Durung Drung basin in the Zanskar Himalaya. We used relevant geomorphic indices interpreted from ASTER DEM satellite data and supplemented by the field observations to decipher active tectonics and resultant changes in the landscape. A N-S trending fault in the north of the basin was studied with the help of basin geometry which includes relative parameter, length area relation, form factor, shape factor ratio, elongation ratio, circulatory ratio, compactness coefficient and morphotectonic indices (e.g., drainage basin asymmetry, mountain front sinuosity, hypsometric integral, topographic symmetric factor) to comprehend the geomorphic signatures of the active tectonics. The geomorphic indices indicate upliftment and tilting of the basin. The data on mountain front index and hypsometric integral reveal the uplift and high relief. We propose that the western side of the basin is tectonically more active than eastern side, suggesting active upliftment. The convex nature of hypsometric curve and strongly elongated circulatory ratio reflect competing role of deformation by tectonics. The results of mountain front index and hypsometric integral reveal high relief and uplift. Overall deglaciation of 12.91% was observed in the basin. Analysis of the meteorological data for the last century (1901–2017) indicate that increase in minimum and maximum temperature coupled with increase in liquid precipitation are probably the main drivers of glacier depletion. We conclude that the drainage system of this basin is structurally controlled and overall landscape change is significantly influenced by the ongoing perturbations in the climate system. [ABSTRACT FROM AUTHOR]

In September 2014, the Kashmir valley (north-west India) experienced a massive flood causing significant economic losses and fatalities. This disaster underlined the high vulnerability of the local population and raised questions regarding the resilience of Kashmiris to future floods. Although the magnitude of the 2014 flood has been considered unprecedented within the context of existing measurements, we argue that the short flow series may lead to spurious misinterpretation of the probability of such extreme events. Here we use a millennium-long record of past floods in Kashmir based on historical and tree-ring records to assess the probability of 2014-like flood events in the region. Our flood chronology (635 CE–nowadays) provides key insights into the recurrence of flood disasters and propels understanding of flood variability in this region over the last millennium, showing enhanced activity during the Little Ice Age. We find that high-impact floods have frequently disrupted the Kashmir valley in the past. Thus, the inclusion of historical records reveals large flood hazard levels in the region. The newly gained information also underlines the critical need to take immediate action in the region, so as to reduce the exposure of local populations and to increase their resilience, despite existing constraints in watershed management related to the Indus Water Treaty. Unlabelled Image • Kashmir has recently suffered extreme flood disasters • Historical and tree-ring flood records show the occurrence of extreme floods events over last millennium • The gained records contribute to a better flood-hazard assessment. • This information is relevant for flood mitigation under the Indus Water Treaty. [ABSTRACT FROM AUTHOR]