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111.
112.
Glacial mass balance changes in the Karakoram and Himalaya based on CMIP5 multi-model climate projections 总被引:1,自引:0,他引:1
Rajiv K. Chaturvedi Anil Kulkarni Yogesh Karyakarte Jaideep Joshi G. Bala 《Climatic change》2014,123(2):315-328
The impact of future climate change on the glaciers in the Karakoram and Himalaya (KH) is investigated using CMIP5 multi-model temperature and precipitation projections, and a relationship between glacial accumulation-area ratio and mass balance developed for the region based on the last 30 to 40 years of observational data. We estimate that the current glacial mass balance (year 2000) for the entire KH region is -6.6?±?1 Gta?1, which decreases about sixfold to -35?±?2 Gta?1 by the 2080s under the high emission scenario of RCP8.5. However, under the low emission scenario of RCP2.6 the glacial mass loss only doubles to -12?±?2 Gta?1 by the 2080s. We also find that 10.6 and 27 % of the glaciers could face ‘eventual disappearance’ by the end of the century under RCP2.6 and RCP8.5 respectively, underscoring the threat to water resources under high emission scenarios. 相似文献
113.
Extreme rainfall events and associated natural hazards in Alaknanda valley, Indian Himalayan region 总被引:2,自引:0,他引:2
JOSHI Varun KUMAR Kireet 《山地科学学报》2006,3(3):228-236
Introduction The Himalaya is considered to be the youngest mountains on the earth, and is tectonically very active, and hence inherently (geologically) vulnerable to hazards. Extreme rainfall events, landslides, debris flows, torrents and flash floods due… 相似文献
114.
115.
BU Tauri (Pleione) an interesting star in the Pleiades cluster, has been observed spectrophotometrically. The energy distribution
curves of the star have been discussed vis a vis model atmospheres for normal stars in the appropriate range of temperature
and effective gravity. The changes in the energy distribution curve noticed during our observations and previous observations
taken from the literature have been pointed out. On the basis of the measured Há emission equivalent width, a rough estimate
of the dimensions of the extended envelope of the star has been made. 相似文献
116.
S. A. Kadam S. D. Gorantiwar S. N. Das A. K. Joshi 《Journal of the Indian Society of Remote Sensing》2017,45(2):297-305
Penman–Monteith method adapted to satellite data was used for the estimation of wheat crop evapotranspiration during the entire growth period using satellite data together with ground meteorological measurements. The IRS-1D/IRS-P6 LISS-III sensor data at 23.5 m spatial resolution for path 096 and row 059 covering the study area were used to derive, albedo, normalized difference vegetation index, leaf area index and crop height and then to estimate wheat crop evapotranspiration referred to as actual evapotranspiration (ETact). The ETact varied from 0.86 to 3.41 mm/day during the crop growth period. These values are on an average 16.40 % lower than wheat crop potential evapotranspiration (ETc) estimated as product of reference crop evapotranspiration estimated by Penman–Monteith method and lysimetric crop coefficient (Kc). The deviation of ETact from ETc is significant, when both the values were compared with t test for paired two sample means. Though the observations on ETact were taken from well maintained unstressed experimental plot of 120 × 120 m size, there was significant deviation. This deviation could be attributed to, the satellite images representing the actual crop evapotranspiration as function crop canopy biophysical parameters, condition of the crop stand, climatic and soil conditions and the microclimate variation over area of one hectare. However, Penman–Monteith method represents a flat rate of specific growth stage of the crop. 相似文献
117.
118.
Guided seismic waves are generated at lateral discontinuities in coal seams as an integral part of the mechanics of scattering downgoing body waves from a surface energy source.Numerical and laboratory model studies undertaken for both thin and thick coal seam waveguides show that small faults generate recognizable diffraction patterns by convertingP andS waves into channel wave arrivals at in-seam geophones on a walkawayVSP profile.These results suggest that in-seam geophones can be used during subsequent surface reflection surveys so as to improve mine profitability by optimising longwall layout in faulted ground. 相似文献
119.
Wetershed management requires spatial knowledge of vegetation attribute, alongwith landuse, socio-economic and physical parameters. Aglar watershed, which drains in the river Yamuna, is situated in a socio-economically backward region. Any development plan in this region will require an approach which considers natural unit of watershed and its parameterisation. The study highlights the utility of space remote sensing data in obtaining spatial information of vegetation and existing landuse through visual interpretation of 1:50,000 scale Landsat TM false colour composite. Aglar watershed has been identified as forested having distinct vegetation distribution and landuse practice in southern and northern aspects of the watershed. Southern aspects are more inhabited and subjected to terrace cultivation and acute shortage of vegetation resources for fuelwood and fodder. The northern aspect is thickly vegetated with low-population density. 相似文献
120.
Anita Joshi 《Solar physics》1995,157(1-2):315-324
This paper presents the results of studies of the asymmetries (N-S and E-W) for different manifestations of solar activity events (sunspot groups, H flares and active prominences/filaments) during the maximum-phase (1989–1991) of solar cycle 22. During the period considered, the results obtained show the existence of a real N-S asymmetry, whereas the E-W asymmetry may exist only for H flares. There is no definite relationship between the asymmetries and the occurrence of events; however, around low activity sometimes we find enhanced asymmetry, and low asymmetry around high activity. Our study suggests a good agreement with similar studies made by others. 相似文献