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21.
Ranganath R. Navalgund Raghavendra P. Singh 《Journal of the Indian Society of Remote Sensing》2011,39(3):281-295
Climate change is associated with earth radiation budget that depends upon incoming solar radiation, surface albedo and radiative forcing by greenhouse gases. Human activities are contributing to climate change by causing changes in Earth’s atmosphere (greenhouse gases, aerosols) and biosphere (deforestation, urbanization, irrigation). Long term and precise measurements from calibrated global observation constellation is a vital component in climate system modelling. Space based records of biosphere, cryosphere, hydrosphere and atmosphere over more than three decades are providing important information on climate change. Space observations are an important source of climate variables due to multi scale simultaneous observation (local, regional, and global scales) capability with temporal revisit in tune with requirements of land, ocean and atmospheric processes. Essential climatic variables that can be measured from space include atmosphere (upper air temperature, water vapour, precipitation, clouds, aerosols, GHGs etc.), ocean (sea ice, sea level, SST, salinity, ocean colour etc.) and land (snow, glacier, albedo, biomass, LAI/fAPAR, soil moisture etc.). India’s Earth Observation Programme addresses various aspects of land, ocean and atmospheric applications. The present and planned missions such as Resourcesat-1, Oceansat-2, RISAT, Megha-Tropiques, INSAT-3D, SARAL, Resourcesat-2, Geo-HR Imager and series of Environmental satellites (I-STAG) would help in understanding the issues related to climate changes. The paper reviews observational needs, space observation systems and studies that have been carried out at ISRO (Indian Space Research Organization) towards mapping/detecting the indicators of climate change, monitoring the agents of climate change and understanding the impact of climate change, in national perspectives. Studies to assess glacier retreat, changes in polar ice cover, timberline change and coral bleaching are being carried out towards monitoring of climate change indicators. Spatial methane inventories from paddy rice, livestock and wetlands have been prepared and seasonal pattern of CO2, and CO have been analysed. Future challenges in space observations include design and placement of adequate and accurate multi-platform observational systems to monitor all parameters related to various interaction processes and generation of long term calibrated climate data records pertaining to land ocean and atmosphere. 相似文献
22.
Sridevi Jade H. J. Raghavendra Rao M. S. M. Vijayan V. K. Gaur B. C. Bhatt Kireet Kumar Saigeetha Jaganathan M. B. Ananda P. Dileep Kumar 《International Journal of Earth Sciences》2011,100(6):1293-1301
Deformation rates derived from GPS measurements made at two continuously operating stations at Leh (34.1°N, 77.6°E) and Hanle
(32.7°N, 78.9°E), and eight campaign sites in the trans-Himalayan Ladakh spanning 11 years (1997–2008), provide a clear picture
of the kinematics of this region as well as the convergence rate across northwestern Himalaya. All the Ladakh sites move 32–34 mm/year
NE in the ITRF2005 reference frame, and their relative velocities are 13–16 mm/year SW in the Indian reference frame and ~19 mm/year W
with reference to the Lhasa IGS station in southeastern Tibet. The results indicate that there is no statistically significant
deformation in the 200-km stretch between the continuous sites Leh and Hanle as well as between Leh and Nubra valley sites
along the Karakoram fault, whereas the sites in and around the splayed Karakoram fault region indicate surface deformation
of 2.5 mm/year. Campaign sites along the Karakoram fault zone indicate a fault parallel surface motion of 1.4–2.5 mm/year
in the Tangste and western Panamik segment of the Karakoram fault, which quantifies the best possible GPS-derived dextral
slip rate of 3 mm/year along this fault during this 11-year period. Baselines of Ladakh sites show convergence rates of 15–18 mm/year
with respect to south India and 12–15 mm/year with respect to Delhi in north India and Almora in the Himalaya ~400 km north-northeast
of Delhi. These constitute an arc normal convergence of 12–15 mm/year across the western Himalaya, which is consistent with
arc normal convergence all along the Himalayan arc from west to east. Baseline extension rates of 14–16 mm/year between Lhasa
and Ladakh sites are consistent with the east–west extension rate of Tibetan Plateau. 相似文献
23.
Rajiv Pandey Nandini Maithani Roberta Aretano Giovanni Zurlini Kelli M. Archie Ajay K. Gupta Vishnu Prasad Pandey 《山地科学学报》2016,13(8):1503-1514
The present study proposes an index to assess the potential for adaptation to climate change for households in the mountainous regions. The index provides a realistic approach to recognize social and natural factors which contribute to successful adaptation and addresses several household functions, such as social networking, livelihood strategy, adjustment strategies, resource availability and accessibility. The proposed Adaptation Capability Index (ACI) is analytically defined, mathematically formulated and field tested on mountainous households in urban and semi-urban regions of the Uttarakhand Himalaya in India. To gather data on the topic relevant to the ACI, a household scale questionnaire was developed and administered to 120 heads of households through face-to-face interviews. The results highlight higher adaptive capability of urban households and low adaptation capacity of rural households due to poor farm productivity, low accessibility and availability of resources and technological input. Future programs and policies must include and implement regulations to remedy attributive factors responsible for higher adaptation. This paper may be applicable to other mountainous regions and may provide insights for effective adaptation strategies to climate change. 相似文献
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25.
Natural Hazards - In the analysis of seismic hazards of a particular region, the site response functions play a significant role. Site response functions for the central seismic gap become more... 相似文献
26.
The use of scrap-tire-shreds as leachate collection layer in landfills would reduce the magnitude of the current tire disposal
problem by converting a waste into a beneficial material. Laboratory studies were conducted to investigate scrap-tire-shreds
as an attractive potential alternative to conventional gravel in the drainage layer of leachate collection system by comparative
analysis of various physico-chemical parameters. Gravel and scrap-tire-shreds in combination were used as leachate collection
layer. Laboratory Test Cells consisting of different combinations of scrap-tire-shreds (size range length = 25.4 mm to 76.1 mm
and width = 5 mm) and gravel (size range 10 mm to 20 mm) beds as leachate collection layer with total bed thickness of 500 mm
were constructed. Performance study of Test Cells- 1 to 7, having different combinations of scrap-tire-shreds and gravel bed
thickness, were studied to work out the best combination. Combined beds of scrap-tire-shreds and gravel gave better results
as compared to conventional gravel or scrap- tire- shreds bed when used singly. Test Cell -3 having scrap-tire-shreds layer
(200 mm) and gravel layer (300 mm) gave the best results in terms of percentage reduction in various physico-chemical parameters
of leachate. The reduction was as high as 68.8 and 79.6% in case of Biological Oxygen Demand (BOD) and Chemical Oxygen Demand
(COD) values respectively. Further, three more laboratory Test Cells-8, 9 and 10 were constructed having scrap-tire-shreds
and gravel layer ratio same as that of Test Cell- 3 (best combination) but having scrap-tire-shreds of different widths 10 mm,
15 mm and 20 mm to find out the most suitable size. Bed of smaller size scrap-tire-shreds (5 mm) gave better results in comparison
to bigger sizes. Leachate sample after passing through combined beds of scrap-tire-shreds and gravel gave better results in
percentage reduction in various physico-chemical parameters of leachate as compared to conventional gravel or scrap-tire-shreds
bed when used singly. 相似文献
27.
There have been very few mesoscale modelling studies of the Indian monsoon, with focus on the verification and intercomparison
of the operational real time forecasts. With the exception of Das et al (2008), most of the studies in the literature are either the case studies of tropical cyclones and thunderstorms or the sensitivity
studies involving physical parameterization or climate simulation studies. Almost all the studies are based on either National
Center for Environmental Prediction (NCEP), USA, final analysis fields (NCEP FNL) or the reanalysis data used as initial and
lateral boundary conditions for driving the mesoscale model. 相似文献
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29.
Ajay Dashora B. Sreenivas Bharat Lohani Javed N. Malik Afroz Ahmad Shah 《Journal of the Indian Society of Remote Sensing》2006,34(2):153-160
Use of high-resolution and historic CORONA satellite photographs for mapping and other purposes requires Ground Control Points
(GCPs), as ephemeris data and image parameters are not available. However, the alterations in landscape in last 34 years (i.e., since the acquisition of these photographs) prevent identification and collection of large number of GCPs in the field.
This paper presents a methodology for collection of GCPs for CORONA photographs. The advantages and limitations of the methodology
are discussed. For a study site, situated in Siwaliks and Lower Himalayas, the GCPs were identified in CORONA photographs
and their WGS84 coordinates were estimated through a process of datum transformation and georeferencing. Estimated GCP coordinates
from the topo sheets and 2D and 3D views of photographs, helped in identifying the GCP locations in field, which were observed
using DGPS. Investigations were carried out to relate Differential Global Positioning System (DGPS) accuracy with base line
length and time of observation. Abase line of 350 km and half an hour observation were found appropriate to yield accuracy
in GCP collection by DGPS method, which conforms to CORONA resolution of 3 m. 相似文献
30.
Ajay Mathur P K Litoria P K Sharma M H Kalubarme 《Journal of the Indian Society of Remote Sensing》1998,26(4):209-214
The present study attempts to conceptualise an approach to integrate the remotely sensed and spatial?n-spatial data generated over the years under Crop Acreage and Production Estimation (CAPE) project through GIS for their easy retrieval and comparison; and to develop a program in dBASE to calculate crop acreage using non-spatial attributes imported from GIS. The “Crop Information System” thus developed would help the planners in analysis/comparison of the database related to crops over the years. 相似文献