Debasish Mitra

Study of Drainage Pattern of Raniganj Coalfield (Burdwan District) as observed on Landsat-TM/IRS LISS II Imagery

Drainage pattern of Raniganj Coalfield basin has been mapped as observed on false colour composites of Landsat TM and IRS-LISS II imagery and their characteristics have been interpreted in terms of basin morphology, surface materials and underlying rock types. The drainage system of the region is composed of 3 perennial rivers with 15 ephemeral nalas and jhors which as a whole flows on recent peneplain basin. Although, on an average, nalas and jhors of the area have smaller stream length and with smaller basinal area but they hold sufficient amount of water during monsoon and therefore by effective planning and management, surface water resources could be enhanced in the region.

Automatic shoreline detection and future prediction: A case study on Puri Coast, Bay of Bengal, India

Abstract Shoreline prediction models have the capability of integrating geoinformatics within them. The present study is conducted on the 142 km-long coastline of Puri district, India. It aims to analyze the change in coastline due to erosion/accretion and provide best estimate of future shoreline positions based on past shorelines. A simple mathematical model, End Point Rate (EPR), has been used to calculate the rate of change of shoreline and its future positions, based on empirical observations. The erosional/accretional scenario has also been analysed by delineating the shoreline from Landsat imageries of 1972, 2001 and 2010. It is found that the northern part of Puri, in the vicinity of Kushabhadra estuary and Chandrabhaga beach undergo high rates of erosion. Based on the delineated shoreline, the short term (2015) and long term (2025) shoreline positions have been predicted.

Geomorphological study of sundarban deltaic estuary

SummaryStudy of landforms in Sundarbans deltaic estuary is necessary in regular basis due to its importance and impact on ecology, climate and economy. Remote sensing has proved as an important tool to study this. Multi-temporal satellite data helps to delineate the various geomorphic classes in different time domain and also provide inputs to study the coastal erosion and accretion. Finer spatial and better temporal resolution will be an added adventure for this kind of study.

Forest cover change prediction using hybrid methodology of geoinformatics and Markov chain model: A case study on sub-Himalayan town Gangtok, India

In the Himalayan states of India, with increasing population and activities, large areas of forested land are being converted into other land-use features. There is a definite cause and effect relationship between changing practice for development and changes in land use. So, an estimation of land use dynamics and a futuristic trend pattern is essential. A combination of geospatial and statistical techniques were applied to assess the present and future land use/land cover scenario of Gangtok, the subHimalayan capital of Sikkim. Multi-temporal satellite imageries of the Landsat series were used to map the changes in land use of Gangtok from 1990 to 2010. Only three major land use classes (built-up area and bare land, step cultivated area, and forest) were considered as the most dynamic land use practices of Gangtok. The conventional supervised classification, and spectral indices-based thresholding using NDVI (Normalized Difference Vegetation Index) and SAVI (Soil Adjusted Vegetation Index) were applied along with the accuracy assessments. Markov modelling was applied for prediction of land use/land cover change and was validated. SAVI provides the most accurate estimate, i.e., the difference between predicted and actual data is minimal. Finally, a combination of Markov modelling and SAVI was used to predict the probable land-use scenario in Gangtok in 2020 AD, which indicted that more forest areas will be converted for step cultivation by the year 2020.

Characterizing the multi-risk with respect to plausible natural hazards in the Balasore coast, Odisha, India: a multi-criteria analysis (MCA) appraisal

Coastal zones are often prone to several natural hazards, and where the coastal zone has high population density and infrastructural assets, these hazards can render severe loss to both life and properties. The present paper reports a comprehensive assessment of the multi-hazard and multi-risk (keeping in view the population and assets exposed to multi-hazards) in the Balasore coast, situated in the state of Odisha, India, facing the Bay of Bengal immediately to its east. In most of the multi-hazard and multi-risk assessments, the importance of any one hazard in relation to others is often determined arbitrarily. To overcome this limitation, this work presents a multi-criteria analysis implemented on six hazards, namely coastal erosion, storm surge, sea level rise, coastal flooding, tsunami, and earthquake. The respective hazards were ranked according to their relative weight computed by pair-wise comparison, and the overall multi-hazard map of the coast was prepared using weighted overlay technique in GIS environment. In order to assess the exposure, population density and urban assets of the study area were also mapped. Finally, the population and urban density data were overlain on the multi-hazard map in order to derive the final map portraying the multi-risk of the Balasore coast. Coastal erosion and storm surge inundation are the two most substantial natural hazards that regularly affect this coast. It is also observed that hazard from the perspective of coastal erosion is spatially concentrated along the central part of the coast, while in the southern part, the effect of storm surge is higher. The area in and around Chandipur, which is situated in the central portion of the Balasore coast, has been found to have the highest multi-risk, which also happens to be a popular tourist destination.

Total column ozone retrieval using INSAT-3D sounder in the tropics: A simulation study

The present study examines the potential of infrared sounder observations from Indian geostationary satellite INSAT-3D for the estimation of total column integrated ozone over the tropical Indian region. A dataset with diverse profiles was used to create training and testing datasets using forward simulations from a radiative transfer model for infrared sounder channels. A study was carried out for the standard tropical atmospheric profile to examine the sensitivity of ozone band radiance corresponding to the atmospheric temperature, water vapour, and ozone mixing ratios at different atmospheric pressure levels. Further, statistical retrieval technique has been used for the total column ozone estimation using two different approaches: (i) ozone channel observation along with the a-priori estimate of temperature and water vapour profile and (ii) only sounder channels observations. The accuracy of the retrieval algorithms was examined for different errors in the atmospheric profiles for the method (i) and different sensor noise specification for the method (ii). This study has shown that accurate temperature information is very important for ozone estimation and lower instrument noise results in better ozone estimates.

An index for discrimination of mangroves from non-mangroves using LANDSAT 8 OLI imagery

Graphical abstract

Environment and Earth Observation

This study attempts the land suitability mapping for the industrial sitting. To facilitate this, base level spatial information, i.e., land use/land cover database has been generated using on-screen interpretation technique from multi-season (Kharif, Rabi, and Zaid) IRS P6—LISS-III satellite images of 2009 and 2011. Information have also been taken for existing infrastructural (transportation) and administrative territorial information up to mouza level, existing industries with their polluting categories (Red, Orange, Green, Exempted, and Proposed), Soil, Land capability, Hydro-geomorphology, and Population density. The study has been conducted on Contai-I block of Purba Medinipur District, West Bengal, INDIA, with the main objective of multicriteria decision-making for industrial site suitability analysis using Advanced Hierarchical Process. The variables are being assigned individual weightage by AHP weightage matrix. Hierarchical weightage mapping has provided with a final suitability map for future industrial prospect. The study area belongs to a backward district in terms of industrial development. So, suggested suitable areas can promote a higher socioeconomic condition of the block retaining the possibilities for sustainable development.

Estimation of Air-Sea CO 2 Exchange and Decadal Change of Surface Water f CO 2 in a Shallow Continental Shelf Using in Situ and Remote Sensing Data During Winter

The air-sea CO2 exchange (fCO2) was estimated in the outer estuary to offshore transition zone of the northern Bay of Bengal using in situ measurements and remote sensing data obtained from moderate resolution imaging spectroradiometer (MODIS) and advanced very high resolution radiometer (AVHRR). The in situ measurements were done during winter months (December, January and February) of the year 2011–12. Sea surface CO2 fugacity (fCO2), sea surface temperature (SST) and chlorophyll-a were measured in situ to develop an empirical relationship with fCO2 but only the SST showed a significant correlation (r 2 = 0.55, n = 64, p < 0.05). This relationship was used to assess fCO2 (water) and its temporal change in decadal scale from the year 2002–2003 to 2011–2012 of the winter months using remotely sensed SST data. The study area acted as a mild sink for atmospheric CO2 at the mean rate of −28 µmol m−2 h−1 (MODIS derived) to −40 µmol m−2 h−1 (AVHRR derived). An overall winter-to-winter increasing trend of fCO2 was observed in the last decade which is accompanied by a similar decrease in the chlorophyll-a concentrations.