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11.
Minakshi P.K. Sharma Amandeep Kaur Vanita Shalley 《Journal of the Indian Society of Remote Sensing》2005,33(1):63-68
This study reveals the temporal changes in the land use/land cover of district Ludhiana from the years 1970 to 2001 and reports
on the change that has occurred in land use/land cover as a result of change in cropping pattern. The changes were analysed
through the data obtained from statistical abstract 1969–70, False Colour Composite (FCC) of IRS-IC LISS-III satellite data
of March 2001 and ground truth. There has been a decrease in agricultural land by 2100 ha. but still it occupies 83.76% of
the total geographical area (TGA). The wasteland shows a declining trend whereas forest cover has increased from 1.07 to 2.71%
of TGA. Area under non-agricultural uses has increased from 10.13 to 12.50% of TGA. There has also been a great change in
the cropping pattern of the district. Crops such as groundnut, gram and cotton have nearly disappeared and wheat and rice
dominate the region. This change has substantially resulted in the decrease of area under wastelands. 相似文献
12.
Parth S. Mahapatra Sipra Panda Namrata Das Satyajit Rath Trupti Das 《Theoretical and Applied Climatology》2014,117(1-2):133-147
Black carbon (BC) mass concentration variation has been studied, over a period of 2 years (June 2010–May 2012) at Bhubaneswar. Daily, monthly and seasonal measurements revealed a clear winter maxima (5.6 μg/m3) of BC followed by post-monsoon (4.05 μg/m3), monsoon (3.02 μg/m3) and pre-monsoon (2.46 μg/m3). Nighttime BC mass concentrations have been found to be distinctly higher during winter followed by post-monsoon and monsoon. Investigations reveal that the winter maxima are due to a stable atmospheric condition and long-range transport over the Indo-Gangetic Plain and Western Asia. Local boundary layer dynamics and anthropogenic activities have been assumed to have a pronounced effect on the diurnal cycle seasonally. Statistical analysis suggests significant variation of BC during the months and non-significant during the days. The study also gives an insight into importance of BC study from health angle and suggests an assessment and management framework. Source apportionment study suggests that BC mass concentration observed at Bhubaneswar is generally dominated by fossil fuel combustion. 相似文献
13.
A.D. Rao S.V. Babu K.V.S.R. Prasad T.V. Ramana Murty Y. Sadhuram D.K. Mahapatra 《Estuarine, Coastal and Shelf Science》2010
SAR (Synthetic Aperture Radar) images in the northwest Bay of Bengal indicate the existence of internal waves and their occurrence and intensity is topography dependent as indicated by in-situ data and satellite information. To complement and comprehend the observations, a three-dimensional Princeton Ocean Model is applied to study the generation and propagation of internal waves. The model domain is configured with a variable curvilinear grid and the input fields comprise bathymetry, initial temperature and salinity, wind stress, air-sea heat flux and tidal information. The numerical investigation indicated a predominant activity of internal waves in the north, and the rationale is three-fold. The first one could be the stable stratification due to fresh water discharge from head-bay major river system, secondly, the significant magnitude/range of the tides and finally, the bathymetry in the coastal waters off Paradip is about 12% shallower compared to that of Visakhapatnam and further south. The cumulative effect of these causes the predominance of internal waves in the north. The core of the energy is essentially in the low-frequency range and the model is able to simulate semi-diurnal and diurnal components reasonably well up to 6 h frequency (0.162 cph). 相似文献
14.
Subhobroto Mazumder Kalyan Adhikari Durga Shanker Mitra Samiran Mahapatra Krishan Kumar Singh Pangtey 《Journal of the Geological Society of India》2016,88(1):87-97
TheAssamArakan fold thrust belt has highly deformed folded units of Tertiary sediments bounded by eastward dipping thrust slices with a convexity towards west. In the Tripura-Cachar region, this folded belt is characterized by the occurrence of wide synclines and narrow anticlines that hosts a number of hydrocarbon producing fields. In the Cachar area of Assam, most of these fields occur in the culmination of anticlinal structures. Other wells drilled in analogous structural settings are found to be dry. In this paper a neotectonic based geomorphic analysis is carried out to delineate a fault network and geomorphic highs in Cachar area as expressions of sub-surface structures which had subsequently been validated by available geophysical data. Of these geomorphic highs, those that are in the synclinal areas are believed to represent subtle sub-surface structural highs. Synclinal structures associated with NNE-SSW faults might be considered interesting for hydrocarbon exploration and are subsequently categorized following their degree of confidence for exploration of hydrocarbon. Additionally, a genetic model of the structures in the region is also proposed. 相似文献
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16.
Natural Hazards - The Andaman–Nicobar–Sumatra (ANS) region is a very hazardous area on the globe, which has witnessed a megathrust earthquake of Mw 9.2 on 26 December 2004 and several... 相似文献
17.
Mageswaran T. Sachithanandam V. Sridhar R. Mahapatra Manik Purvaja R. Ramesh R. 《Natural Hazards》2021,109(2):1717-1741
Natural Hazards - We report here a four decades of shoreline changes and possible sea level rise (SLR) impact on land use/land cover (LULC) in Little Andaman Island by using remote sensing (RS) and... 相似文献
18.
Samir Pokhrel H. S. Chaudhari Subodh K. Saha Ashish Dhakate R. K. Yadav Kiran Salunke S. Mahapatra Suryachandra A. Rao 《Climate Dynamics》2012,39(9-10):2143-2165
El Ni?o-Southern Oscillation (ENSO), Indian Ocean Dipole (IOD) and Indian Summer Monsoon rainfall features are explored statistically and dynamically using National Centers for Environment Prediction (NCEP) Climate Forecast System (CFSv1) freerun in relation to observations. The 100?years of freerun provides a sufficiently long homogeneous data set to find out the mean state, periodicity, coherence among these climatic events and also the influence of ENSO and IOD on the Indian monsoon. Differences in the occurrence of seasonal precipitation between the observations and CFS freerun are examined as a coupled ocean–atmosphere system. CFS simulated ENSO and IOD patterns and their associated tropical Walker and regional Hadley circulation in pure ENSO (PEN), pure IOD (PIO) and coexisting ENSO-IOD (PEI) events have some similarity to the observations. PEN composites are much closer to the observation as compared to PIO and PEI composites, which suggest a better ENSO prediction and its associated teleconnections as compared to IOD and combined phenomenon. Similar to the observation, the model simulation also show that the decrease in the Indian summer monsoon rainfall during ENSO phases is associated with a descending motion of anomalous Walker circulation and the increase in the Indian summer monsoon rainfall during IOD phase is associated with the ascending branch of anomalous regional Hadley circulation. During co-existing ENSO and IOD years, however, the fate of Indian summer monsoon is dictated by the combined influence of both of them. The shift in the anomalous descending and ascending branches of the Walker and Hadley circulation may be somewhat attributed to the cold (warm) bias over eastern (western) equatorial Indian Ocean basin, respectively in the model. This study will be useful for identifying some of the limitations of the CFS model and consequently it will be helpful in improving the model to unravel the realistic coupled ocean–atmosphere interactions for the better prediction of Indian Summer Monsoon. 相似文献
19.
Parth Sarathi Mahapatra Sanak Ray Namrata Das Ayusman Mohanty T. S. Ramulu Trupti Das G. Roy Chaudhury S. N. Das 《Theoretical and Applied Climatology》2013,112(1-2):243-251
Acid- and water-soluble component of suspended particulate matter was studied from January 2009 to December 2009 at Bhubaneshwar, an urban coastal location of eastern India, by high-volume sampler, environmental dust monitor using GRIMM®, and scanning electron microscope and energy dispersive X-ray spectrometer. The water-soluble components accounted for 30–45 % of the total suspended particulate matter, and the major elements were observed to be ammonium and nitrate as the cationic and anionic species, respectively. The acid-soluble component like copper, nickel, cobalt, iron, and lead accounted for 5–15 % of the total particulate matter concentration. The composition of particulate matter shows a clear seasonal variation in relation to wind speed, wind direction, and trajectories of the air mass movement. The GRIMM spectrometer analysis shows higher concentration of fine particulate matter. Source apportionment and enrichment factor analysis indicated that except sodium and chloride, all other elements have emerged from different sources such as crustal as well as anthropogenic. 相似文献
20.
Coal mine fires due to spontaneous heating have been a great concern both for the industry and researchers worldwide. They start in a very small scale and gradually expand in size resulting in environmental, safety and economic concerns. Most of these fires could be averted if suitable preventive measures are taken. Since the spontaneous heating potential of all types of coals are not the same, its accurate forecasting is essential to plan efficient preventive measures, production schedule and storage capabilities of a mine. This study presents a neuro-fuzzy approach for forecasting the auto-oxidation of coals based on laboratory test results on fifty cone coal samples collected from different coalfields of India. Using the constituents of proximate analysis as input parameters, crossing point temperature (CPT) is predicted using adaptive neuro-fuzzy inference system (ANFIS) model. Gaussian membership function has been adopted for describing the input variables. The results indicate that ANFIS model can predict CPT values with reasonable accuracy. 相似文献