bluuebunny/crossref_metadata_2025 huggingface dataset:
Simulation of the isotopic composition of stratospheric water vapour – Part 2: Investigation of HDO/H2O variations
Authors: Eichinger R. , Jöckel P. , Lossow S.
Published: November 2014

Abstract. Studying the isotopic composition of water vapour in the lower stratosphere can reveal the driving mechanisms of changes in the stratospheric water vapour budget and therefore help to explain the trends and variations of stratospheric water vapour during the recent decades. We equipped a global chemistry climate model with a description of the water isotopologue HDO, comprising its physical and chemical fractionation effects throughout the hydrological cycle. We use this model to improve our understanding of the processes, which determine the patterns in the stratospheric water isotope composition and in the water vapour budget, itself. The link between the water vapour budget and its isotopic composition in the tropical stratosphere is presented through their correlation in a simulated 21 year time series. The two quantities depend on the same processes, however, are influenced with different strengths. A sensitivity experiment shows that fractionation effects during the oxidation of methane has a damping effect on the stratospheric tape recorder signal in the water isotope ratio. Moreover, the chemically produced high water isotope ratios overshadow the tape recorder in the upper stratosphere. Investigating the origin of the boreal summer tape recorder signal in the lower stratosphere reveals isotopically enriched water vapour crossing the tropopause over the subtropical Western Pacific. A correlation analysis confirms this link, which identifies the Asian Summer Monsoon as the major contributor for the intrusion of isotopically enriched water vapour into the stratosphere during boreal summer. Furthermore, convective ice lofting is shown to have a substantial impact on the isotope ratios of water vapour in the upper troposphere and lower stratosphere.
Compilation of Henry's law constants, version 3.99
Authors: Sander R.
Published: November 2014

Abstract. Many atmospheric chemicals occur in the gas phase as well as in liquid cloud droplets and aerosol particles. Therefore, it is necessary to understand the distribution between the phases. According to Henry's law, the equilibrium ratio between the abundances in the gas phase and in the aqueous phase is constant for a dilute solution. Henry's law constants of trace gases of potential importance in environmental chemistry have been collected and converted into a uniform format. The compilation contains 14775 values of Henry's law constants for 3214 species, collected from 639 references. It is also available on the internet at http://www.henrys-law.org.
Wuhan Atmospheric Radio Exploration (WARE) radar: implementation and initial results
Authors: Zhou C. , Qing H. , Chen G. , Gu X. , Ni B. , Yang G. , Zhang Y. , Zhao Z.
Published: November 2014

Abstract. The recently constructed Wuhan Atmospheric Radio Exploration (WARE) radar is the first mesosphere-stratosphere-troposphere (MST) radar in the mainland of China, located at Chongyang, Hubei Province (114°8'8'' E, 29°31'58'' N, ∼ 23° geomagnetic latitude). WARE radar has a capability of probing the structure and dynamics of the atmosphere at the altitudes from 3 to 100 km (excluding 25–60 km). With fine temporal and spatial resolution, WARE radar provides an outstanding opportunity for the first time to extensively and intensively investigate various atmospheric phenomena at the regions of mid-latitude China. In this paper, we present the main configuration and technical specifications of WARE radar system. For the first time, we also report some initial results obtained by the WARE radar: (1) wind field observations from 69 to 85 km and from 3.2 to 16.9 km together with their comparisons with the rawinsonde results, (2) tropopause heights determined by radar echo power and comparisons between radar tropopause and rawinsonde tropopause, (3) atmospheric gravity waves in the troposphere with the wave length and propagation direction analyzed using the hodograph method, (4) aspect sensitivity of echo power at six specified heights in the troposphere and stratosphere, and (5) diurnal and semi-diurnal tides at the tropospheric and low stratospheric heights analyzed by the Lomb–Scargle periodogram method.
Forest conversion to poplar plantation in a Lombardy floodplain (Italy): effects on soil organic carbon stock
Authors: Ferré C. , Comolli R. , Leip A. , Seufert G.
Published: November 2014

Abstract. Effects of forest conversion to poplar plantation on soil organic carbon (SOC) stocks were investigated by sampling paired plots in an alluvial area of the Ticino River in Northern Italy. According to land registers and historical aerial photographs, the two sites were part of a larger area of a 200 yr old natural forest that was partly converted to poplar plantation in 1973. The soil sampling of three layers down to a depth of 100 cm was performed at 90 and 70 points in the natural forest (NF) and in the nearby poplar plantation (PP) respectively. The substitution of the natural forest with the poplar plantation strongly modified soil C stock down to a depth of 55 cm, although the management practices at PP were not intensive. After calculation of equivalent soil masses and of SOC stocks in individual texture classes, the comparison of C stocks showed an overall decrease in SOC of 5.7 kg m−2 or 40% in consequence of 37 years of poplar cultivation. Our case study provides further evidence that (i) spatial heterogeneity of SOC is an important feature in paired plot studies requiring a careful sampling strategy and high enough number of samples; (ii) land use changes through tillage are creating a more homogeneous spatial structure of soil properties and may require the application of dedicated spatial statistics to tackle eventual problems of pseudo-replicates and auto-correlation; (iii) short rotation forests are not properly represented in current reporting schemes for changes of SOC after land use change and may better be considered as cropland.
Results from a full coupling of the HIRHAM regional climate model and the MIKE SHE hydrological model for a Danish catchment
Authors: Larsen M. A. D. , Refsgaard J. C. , Drews M. , Butts M. B. , Jensen K. H. , Christensen J. H. , Christensen O. B.
Published: November 2014

Abstract. A major challenge in the emerging research field of coupling of existing regional climate models (RCMs) and hydrology/land-surface models is the computational interaction between the models. Here we present results from a full two-way coupling of the HIRHAM RCM over a 4000 km × 2800 km domain at 11 km resolution and the combined MIKE SHE-SWET hydrology and land-surface models over the 2500 km2 Skjern River catchment. A total of 26 one-year runs were performed to assess the influence of the data transfer interval (DTI) between the two models and the internal HIRHAM model variability of 10 variables. DTI frequencies between 12 and 120 min were assessed, where the computational overhead was found to increase substantially with increasing exchange frequency. In terms of hourly and daily performance statistics the coupled model simulations performed less accurately than the uncoupled simulations, whereas for longer-term cumulative precipitation the opposite was found, especially for more frequent DTI rates. Four of six output variables from HIRHAM, precipitation, relative humidity, wind speed and air temperature, showed statistically significant improvements in root-mean-square error (RMSE) by reducing the DTI. For these four variables, the HIRHAM RMSE variability corresponded to approximately half of the influence from the DTI frequency and the variability resulted in a large spread in simulated precipitation. Conversely, DTI was found to have only a limited impact on the energy fluxes and discharge simulated by MIKE SHE.
SPCA Assisted Correlation Clustering of Hyperspectral Imagery
Authors: Mehta A. , Dikshit O.
Published: November 2014

Abstract. In this study, correlation clustering is introduced to hyperspectral imagery for unsupervised classification. The main advantage of correlation clustering lies in its ability to simultaneously perform feature reduction and clustering. This algorithm also allows selection of different sets of features for different clusters. This framework provides an effective way to address the issues associated with the high dimensionality of the data. ORCLUS, a correlation clustering algorithm, is implemented and enhanced by making use of segmented principal component analysis (SPCA) instead of principal component analysis (PCA). Further, original implementation of ORCLUS makes use of eigenvectors corresponding to smallest eigenvalues whereas in this study eigenvectors corresponding to maximum eigenvalues are used, as traditionally done when PCA is used as feature reduction tool. Experiments are conducted on three real hyperspectral images. Preliminary analysis of algorithms on real hyperspectral imagery shows ORCLUS is able to produce acceptable results.
Support Vector Machine (SVM) based Rain Area Detection from Kalpana-1 Satellite Data
Authors: Upadhyaya S. , Ramsankaran R. A. A. J.
Published: November 2014

Abstract. Rain is one of the major components of water cycle; extreme rain events can cause destruction and misery due to flash flood and droughts. Therefore, assessing rainfall at high temporal and spatial resolution is of fundamental importance which can be achieved only by satellite remote sensing. Though there are many algorithms developed for estimation of rainfall using satellite data, they suffer from various drawbacks. One such challenge in satellite rainfall estimation is to detect rain and no-rain areas properly. To address this problem, in the present study we have used the Support Vector Machines (SVM). It is significant to note that this is the first study to report the utility of SVM in detecting rain and no-rain areas. The developed SVM based index performance has been evaluated by comparing with two most popular rain detection methods used for Indian regions i.e. Simple TIR threshold used in Global Precipitation Index (GPI) technique and Roca method used in Insat Multi Spectral Rainfall Algorithm (IMSRA). Performance of the above considered indices has been analyzed by considering various categorical statistics like Probabil ity of Detection (POD), Probability of no-rain detection (POND), Accuracy, Bias, False Alarm Ratio (FAR) and Heidke Skill Score (HSS). The obtained results clearly show that the new SVM based index performs much better than the earlier indices.
Spatial Coherence of winds and waves over the Arabian Sea and Bay of Bengal and their evolution during SW Monsoon: a novel application of along-track Radar Altimeter measurements from Space
Authors: Bhandari S. M. , Hareef Baba Shaeb K.
Published: November 2014

Abstract. We have examined, for the first time, the spatial coherence of oceanic parameters, namely, the ocean surface wind and significant wave height (SWH), using near-instantaneous along-track sampling over vast oceanic tracks provided by Poseidon-2 Radar Altimeter onboard Jason-1. The spatial coherence length scales over the Arabian Sea and the Bay of Bengal regions, derived using Auto correlation analysis, display interesting characteristics in relation to onset and evolution of SW Monsoon over India. The estimated spatial coherence scales are found to be of the order of 100–500 km. Generally, SWH coherence lengths over Arabian Sea are observed to increase from June to July during good monsoon year (2012). This trend is not followed for the poor monsoon year (2002). Similar trend is observed for spatial coherence scales for wind speed. The temporal evolution of analyzed spatial coherence scales of winds and waves over Arabian Sea clearly brings out the distinction between a "good" (2012) and a "poor" (2002) monsoon year. The spatial coherence lengths of these parameters over the Bay of Bengal are found to be shorter and do not show any systematic relation to onset and evolution of SW monsoon. Anisotropy in coherence lengths is also analyzed by treating ascending and descending tracks separately. Generally, the descending tracks measurements show higher spatial coherence lengths than the ascending ones. Like the spatial coherence scales, the anisotropy of the coherence scales over the Arabian Sea also mimics the behaviour of the strength of SW Monsoon.
Fusion of Hyperspectral and Multispectral Image Data for Enhancement of Spectral and Spatial Resolution
Authors: Chakravortty S. , Subramaniam P.
Published: November 2014

Abstract. Hyperspectral image enhancement has been a concern for the remote sensing society for detailed end member detection. Hyperspectral remote sensor collects images in hundreds of narrow, continuous spectral channels, whereas multispectral remote sensor collects images in relatively broader wavelength bands. However, the spatial resolution of the hyperspectral sensor image is comparatively lower than that of the multispectral. As a result, spectral signatures from different end members originate within a pixel, known as mixed pixels. This paper presents an approach for obtaining an image which has the spatial resolution of the multispectral image and spectral resolution of the hyperspectral image, by fusion of hyperspectral and multispectral image. The proposed methodology also addresses the band remapping problem, which arises due to different regions of spectral coverage by multispectral and hyperspectral images. Therefore we apply algorithms to restore the spatial information of the hyperspectral image by fusing hyperspectral bands with only those bands which come under each multispectral band range. The proposed methodology is applied over Henry Island, of the Sunderban eco-geographic province. The data is collected by the Hyperion hyperspectral sensor and LISS IV multispectral sensor.
Shadow Analysis Technique for Extraction of Building Height using High Resolution Satellite Single Image and Accuracy Assessment
Authors: Raju P. L. N. , Chaudhary H. , Jha A. K.
Published: November 2014

Abstract. These High resolution satellite data with metadata information is used to extract the height of the building using shadow. Proposed approach divides into two phases 1) rooftop and shadow extraction and 2) height estimation. Firstly the rooftop and shadow region were extracted by manual/ automatic methods using Example – Based and Rule – Based approaches. After feature extraction next step is estimating height of the building by taking rooftop in association with shadow using Ratio Method and by using the relation between sun-satellite geometry. The performance analysis shows the total mean error of height is 0.67 m from ratio method, 1.51 m from Example – Based Approach and 0.96 m from Rule – Based Approach. Analysis concluded that Ratio Method i.e. manual method is best for height estimation but it is time consuming so the automatic Rule Based approach is best for height estimation in comparison to Example Based Approach because it require more knowledge and selection of more training samples as well as slows the processing rate of the method.
Capacity Building through Geospatial Education in Planning and School Curricula
Authors: Kumar P. , Siddiqui A. , Gupta K. , Jain S. , Krishna Murthy Y. V. N.
Published: November 2014

Abstract. Geospatial technology has widespread usage in development planning and resource management. It offers pragmatic tools to help urban and regional planners to realize their goals. On the request of Ministry of Urban Development, Govt. of India, the Indian Institute of Remote Sensing (IIRS), Dehradun has taken an initiative to study the model syllabi of All India Council for Technical Education for planning curricula of Bachelor and Master (five disciplines) programmes. It is inferred that geospatial content across the semesters in various planning fields needs revision. It is also realized that students pursuing planning curricula are invariably exposed to spatial mapping tools but the popular digital drafting software have limitations on geospatial analysis of planning phenomena. Therefore, students need exposure on geospatial technologies to understand various real world phenomena. Inputs were given to seamlessly merge and incorporate geospatial components throughout the semesters wherever seems relevant. Another initiative by IIRS was taken to enhance the understanding and essence of space and geospatial technologies amongst the young minds at 10+2 level. The content was proposed in a manner such that youngsters start realizing the innumerable contributions made by space and geospatial technologies in their day-to-day life. This effort both at school and college level would help in not only enhancing job opportunities for young generation but also utilizing the untapped human resource potential. In the era of smart cities, higher economic growth and aspirations for a better tomorrow, integration of Geospatial technologies with conventional wisdom can no longer be ignored.
Diurnal Difference Vegetation Water Content (ddVWC) of Advance Microwave Scanning Radiometer-Earth Observing System (AMSR-E) for assessment of crop water stress at regional level
Authors: Chakraborty A. , Sesha Sai M. V. R.
Published: November 2014

Abstract. Advance Microwave Scanning Radiometer – Earth Observing System (AMSR-E) derived Vegetation Water Content (VWC) at predawn (01:30 LST, descending pass) and afternoon (13:30 LST; ascending pass) were used to assess crop water stress condition over the selected meteorological subdivisions of India. The temporal profile of Normalized Difference Vegetation Index (NDVI) was used to study the progression of crop growth. The Diurnal Difference Vegetation Water Content (ddVWC) was found to be sensitive to rainfall patterns (wet/dry spell) particularly in moderate to full crop cover condition (NDVI > 0.4). The ddVWC was found to be significantly (p = 0.05) correlated with the rainfall over the rainfed regions. The ddVWC was further characterized to represent different categories of crop water stress considering irrigated flooded rice crop as a benchmark. Inter year comparative analysis of temporal variations of the ddVWC revealed its capability to differentiate normal (2005) and sub-normal years (2008 and 2009) in term of intensity and persistence of crop water stress. Spatio-temporal patterns of ddVWC could capture regional progression of crop water stress at high temporal resolution in near real time.
Study Relating to the Spatial Distribution of Ground Water Quality for Different Elements using Legacy Data of RWS&S, Andhra Pradesh, India
Authors: Prakash P. , Kumar Das A. , Sandilya C. V. S.
Published: November 2014

Abstract. The state of Andhra Pradesh, India falls in water stress4 area. The primary objective of this study is to examine the spatial distribution of different chemical elements with respect to its contamination level. About 70 % of drinking water needs in rural areas and 40 % drinking water needs in urban areas are met from groundwater resources. In the last decades, rapid population growth coupled with agricultural expansion due to subsidized power to agriculture has significantly increased demand on groundwater resources. Combined to this, the effect of Global warming has put stress on ground water which is resulting in declines in water levels and deterioration of ground water quality. This may be evidenced by the fact that the phreatic aquifer which was in use two decades ago, is existing no more now in some of the parts of the study area and the water is being drawn from deeper aquifers beyond phreatic aquifers. The study has been carried out for which one or more elements are contaminated and to study its spatial distribution.
Study on Karst Rock Desertification by Human-Nature Interaction: A Case Study of Fengshan County of Guangxi, China
Authors: Zhou G. , Su C. , Zhang R. , Shi Y. , Liu Y. , Ma Y.
Published: November 2014

Abstract. Rocky desertification is a process of soil erosion leading to the bareness of bedrock, and is a kind of typical natural disaster in karst areas, which seriously constrains the developments of local society and economy. This paper studies the impact of human activities on the changes of rocky desertification. With the interpretation of remote sensing images of Fengshan County, GuangXi, China covering 1990, 1995 and 2005, this paper analyzes the relationship of the changes of social and economic index (including population density, agricultural population, rural per capital net income, and farmland) and the changes of rocky desertification in recent 15 years. The results indicate that: in recent 15 years, the average annual growth rate of rocky desertification, rate of change of population density, agricultural population, rural per capita net income, and farmland area are 8.7375 km2 /year, 0.7 person/km2.year, 1153 person/year, 85 Yuan/year, and −269.1 ha/year, respectively. The first three of social and economic indicators at different degrees of growth, show a positive correlation with rocky desertification change. However, farmland area, which has been diminishing, shows a negative correlation with rocky desertification. The influence of human activities for karst rocky desertification can be regarded as population growth – steep slope reclamation – the destruction of vegetation – erosion – rocky desertification – poverty.
Measurement of glacier velocity at Pik Lenin, Tajikistan, by feature tracking
Authors: Kumari S. , Ghosh S. K. , Buchroithner M. F.
Published: November 2014

Abstract. Glaciers, especially in mountain area are sensitive indicators of climate fluctuations and also contribute to present rates of sea level rise. In Central Asia, these glaciers are the primary resource for fresh water. Understanding the seasonal behavior of these glaciers would help to make efficient use of the available water reservoir. Different methods have been employed to study glacier displacements in past. The conventional survey techniques are very cost-intensive and highly depend on accessibility to high mountain glaciers also directs us to look for new ways to study these areas. Here remote sensing comes in handy with freely available data and a good coverage with high spatial and temporal resolution. Optical satellite imagery, available free can be effectively used for research purpose. The glacier in this region fed lake Karakul (380 km2), the largest Lake in Tajikistan. The objective is to study the displacement tendency of the Glacier in Pik Lenin area using Landsat 7 dataset. Normalized cross correlation algorithm has been implemented via CIAS to estimate the motion of glacier surface. A number of combination of reference block and search area size were tested for 30 m resolution dataset. As a result the specifications: reference block size of 15 pixels and search area size of 10 pixels was found out as the best set of parameters and considered for further processing. The study derives a reliable set of data depicting the velocities in the glacier which after post processing shows peak velocity of 121 m/y of the glacier.
Enhancement of snow cover change detection with sparse representation and dictionary learning
Authors: Varade D. , Dikshit O.
Published: November 2014

Abstract. Sparse representation and decoding is often used for denoising images and compression of images with respect to inherent features. In this paper, we adopt a methodology incorporating sparse representation of a snow cover change map using the K-SVD trained dictionary and sparse decoding to enhance the change map. The pixels often falsely characterized as "changes" are eliminated using this approach. The preliminary change map was generated using differenced NDSI or S3 maps in case of Resourcesat-2 and Landsat 8 OLI imagery respectively. These maps are extracted into patches for compressed sensing using Discrete Cosine Transform (DCT) to generate an initial dictionary which is trained by the K-SVD approach. The trained dictionary is used for sparse coding of the change map using the Orthogonal Matching Pursuit (OMP) algorithm. The reconstructed change map incorporates a greater degree of smoothing and represents the features (snow cover changes) with better accuracy. The enhanced change map is segmented using kmeans to discriminate between the changed and non-changed pixels. The segmented enhanced change map is compared, firstly with the difference of Support Vector Machine (SVM) classified NDSI maps and secondly with a reference data generated as a mask by visual interpretation of the two input images. The methodology is evaluated using multi-spectral datasets from Resourcesat-2 and Landsat-8. The k-hat statistic is computed to determine the accuracy of the proposed approach.
Estimating the atmospheric phase delay for quantifying co-seismic deformation using repeat pass Differential SAR Interferometry: Observations from 20th April 2013 Lushan (China) Earthquake
Authors: Mathew J. , Majumdar R. , Vinod Kumar K.
Published: November 2014

Abstract. Atmospheric phase contribution significantly influences co-seismic surface deformation estimates from repeat pass Differential Synthetic Aperture Radar Interferometry (DInSAR). Present study investigates the contribution of the atmosphere in co-seismic deformation estimation associated with the 20 April 2013 Lushan (China) earthquake. The Lushan Earthquake occurred in the south-western segment of the Longmenshan fault zone, on the eastern margin of the Qinghai-Tibetan Plateau. Using pre- and postearthquake Radarsat-2 interferometric pair, the co-seismic deformation of the Lushan earthquake has been estimated. The tropospheric phase delay component has been estimated using tropospheric models in conjunction with surface temperature and pressure data from MODIS atmospheric products. The ionospheric phase component has been computed using the Total Electron Content (TEC) data. The net atmospheric path addition in the study area varies from 3.022 m to 4.621 m for the pre-earthquake SAR acquisition and from 2.687 m to 4.199 m for the post-event data acquisition. Comparison of the Line of Sight (LOS) displacement values computed using un-corrected and corrected interferometric data shows that the atmospheric phase component has introduced considerable contribution in the LOS displacement values. The uncorrected LOS displacement values vary from 0.902 m to −0.157 m where as those from the phase-corrected interferometric data are in the range of 0.052 m and −0.062 m. The corrected LOS displacement values show close agreement to a few GPS based co-seismic surface deformation components from published literature. Thus removal of atmospheric phase contribution is a necessary step in using repeat pass DInSAR for co-seismic surface deformation estimation.
Ecological Niche Modelling using satellite data for assessing distribution of threatened species Ceropegia bulbosa Roxb.
Authors: Kumar S. , Kulloli R. N. , Tewari J. C. , Singh J. P. , Singh A.
Published: November 2014

Abstract. Ceropegia bulbosa Roxb. is a narrow endemic, tuberous twiner of Asclepiadaceae family. It is medicinally important: tubers are nutritive and edible, leaves are digestive and a cure for dysentery and diarrhea. Exploitation for its tubers and poor regeneration of this species has shrunk its distribution. In order to know its present status, we report here the results of its appraisal in Rajasthan, using remote sensing and ground truthing in the past five years (2009–14). A base map of C. bulbosa was prepared using Geographical Information System (GIS), open source software Quantum GIS, SAGA. The Landsat Enhanced Thematic Mapper (ETM) +Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), Global Digital Elevation Model (GDEM) Satellite Data were used in this study. ASTER and GDEM Data was clipped with district boundary and provided color range to get elevation information. A digital elevation model of Rajasthan physiography was developed from ASTER GDEM of 30-m resolution. GIS layers of Area of occurrences for C. bulbosa plant and elevation were created. This map along with topographic sheets of 1:50000 were used for field traversing and ground truthing as per GPS location inferred from map. Its geographic distribution was assessed using MaxEnt distribution modelling algorithm that employed 12 presence locality data, 19 bioclimatic variables, and elevation data. Results of this modelling predicted occurrence of C. bulbosa in the districts of Sirohi, Jalore, Barmer, Pali, Ajmer, Jhalawar, Dungarpur, Banswara, Baran, Kota, Bundi and Chittorgarh. Ground validation in these districts revealed its presence only at four places in three districts confirming its rarity. Analysis of dominance at their sites of occurrence revealed their poor populations and sub dominant status (RIV = 20–32) and very low density (2–12 plants per tenth ha).
POLINSAR Coherence-Based Regression Analysis of Forest Biomass Using RADARSAT-2 Datasets
Authors: Singh J. , Kumar S. , Kushwaha S. P. S
Published: November 2014

Abstract. Forests play a pivotal role in synchronizing earth’s carbon cycle by absorbing carbon from the atmosphere and storing it in the form of biomass. Researchers today are trying to understand the climatic variations, especially those occurring due to destruction of forest and its corresponding biomass loss. Hence, quantification of various forest parameters such as biomass is imperative for evaluating the carbon. The objective of this research was to exploit the potential of C-band Radarsat-2 Polarimetric Interferometric Synthetic Aperture Radar (PolInSAR) technique for analysing the relationship between complex coherence and field-estimated aboveground biomass. Association between the backscatter and the aboveground biomass was also established in the process. To serve our objective, Radarsat-2 interferometric pair dated 4th March, 2013 (master image) and 28th March, 2013 (slave image) were procured for the Barkot Reserve Forest region of Dehradun, India. Field sampling was done for 30 plots (31.62 m x 31.62 m) and stem diameter and tree height were measured in each plot. The study emphasized on the application of POLINSAR coherence instead of using conventional method of relying on backscatter values for retrieving forest biomass. Coherence matrices were utilized for generating complex coherence values for different polarization channels and were regressed against field estimated aboveground biomass. Results indicated a negative linear relationship between complex coherence and aboveground biomass with the cross – polarized coherence showing the highest R2 value of 0.71. Further, the backscatter mechanism when studied with respect to aboveground biomass indicated a positive linear relationship between backscatter values and field estimated aboveground biomass with R2 value of 0.45 and 0.61 for slave and master image respectively. The results suggest that PolInSAR technique, in combination with different modelling approaches, can be adopted for estimating forest biomass.
Landform monitoring in active volcano by UAV and SfM-MVS technique
Authors: Nakano T. , Kamiya I. , Tobita M. , Iwahashi J. , Nakajima H.
Published: November 2014

Abstract. Nishinoshima volcano in Ogasawara Islands has erupted since November, 2013. This volcanic eruption formed and enlarged a new island, and fused the new island with the old Nishinoshima Island. We performed automated aerial photographing using an Unmanned Aerial Vehicle (UAV) over the joined Nishinoshima Island on March 22 and July 4, 2014. We produced ortho-mosaic photos and digital elevation model (DEM) data by new photogrammetry software with computer vision technique, i.e. Structure from Motion (SfM) for estimating the photographic position of the camera and Multi-view Stereo (MVS) for generating the 3-D model. We also estimated the area and volume of the new island via analysis of ortho-mosaic photo and DEM data. Transition of volume estimated from the UAV photographing and other photographing shows the volcanic activity still keeps from initial level. The ortho-mosaic photos and DEM data were utilized to create an aerial photo interpretation map and a 3-D map. These operations revealed new knowledge and problems to be solved on the photographing and analysis using UAV and new techniques as this was first case in some respects.
Geo-Environmental Appraisal For Studying Urban Environment And Its Associated Biophysical Parameters Using Remote Sensing And GIS Technique
Authors: Ganguly K. , Ravi Shankar G.
Published: November 2014

Abstract. This study investigated the influences of urbanization on urban ecological and thermal environment as well as the relationships of all the biophysical parameters with each other utilizing multi-temporal datasets of CORONA (1967), Landsat TM (1992 and 2009), Landsat ETM+ (2002), IRS R2 LISS-3 (2012) and Landsat 8 (2014). The urban environmental issues related to land use and land cover, greenness, surface wetness and impervious surface were assessed using change detection, SAVI, MNDWI and IBI models respectively. The land surface temperature (LST) was also retrieved from thermal infrared band of each Landsat TM, ETM+ and Landsat 8. Based on these parameters, the urban expansion, urban heat island effect and the relationships of LSTs to other biophysical parameters were analyzed. Results indicate the area ratio of impervious surface in Pune sub-urban zone increased significantly, which grew from 1.41 % in 1967 to 8.47 % in 1992 and further to 22.45 % and 44.7 % in 2002 and 2014 respectively. Simultaneously, the intensity of urban heat island increased in observed years. A correlation analyses revealed that, the association of impervious surface to other two variables i.e. greenness and land surface wetness is negatively correlated (R2 = 0.616 and 0.607 respectively). Whereas, LST possessed a strong positive correlation with impervious surfaces (R2 = 0.658). The present study provided an integrated research approach and the outcome of the study is very useful in environmental modelling and sustainable development of urban areas and natural resources conservation.
Urban land cover classification using hyperspectral data
Authors: Hegde G. , Mohammed Ahamed J. , Hebbar R. , Raj U.
Published: November 2014

Abstract. Urban land cover classification using remote sensing data is quite challenging due to spectrally and spatially complex urban features. The present study describes the potential use of hyperspectral data for urban land cover classification and its comparison with multispectral data. EO-1 Hyperion data of October 05, 2012 covering parts of Bengaluru city was analyzed for land cover classification. The hyperspectral data was initially corrected for atmospheric effects using MODTRAN based FLAASH module and Minimum Noise Fraction (MNF) transformation was applied to reduce data dimensionality. The threshold Eigen value of 1.76 in VNIR region and 1.68 in the SWIR region was used for selection of 145 stable bands. Advanced per pixel classifiers viz., Spectral Angle Mapper (SAM) and Support Vector Machine (SVM) were used for general urban land cover classification. Accuracy assessment of the classified data revealed that SVM was quite superior (82.4 per cent) for urban land cover classification as compared to SAM (67.1 per cent). Selecting training samples using end members significantly improved the classification accuracy by 20.1 per cent in SVM. The land cover classification using multispectral LISS-III data using SVM showed lower accuracy mainly due to limitation of spectral resolution. The study indicated the requirement of additional narrow bands for achieving reasonable classification accuracy of urban land cover. Future research is focused on generating hyperspectral library for different urban features.
Characterizing multi-dimensionality of urban sprawl in Jamnagar, India using multi-date remote sensing data
Authors: Jain G. , Sharma S. , Vyas A. , Rajawat A. S.
Published: November 2014

Abstract. This study attempts to measure and characterize urban sprawl using its multiple dimensions in the Jamnagar city, India. The study utilized the multi-date satellite images acquired by CORONA, IRS 1D PAN & LISS-3, IRS P6 LISS-4 and Resourcesat-2 LISS-4 sensors. The extent of urban growth in the study area was mapped at 1 : 25,000 scale for the years 1965, 2000, 2005 and 2011. The growth of urban areas was further categorized into infill growth, expansion and leapfrog development. The city witnessed an annual growth of 1.60 % per annum during the period 2000–2011 whereas the population growth during the same period was observed at less than 1.0 % per annum. The new development in the city during 2000–2005 time period comprised of 22 % as infill development, 60 % as extension of the peripheral urbanized areas, and 18 % as leapfrogged development. However, during 2005–2011 timeframe the proportion of leapfrog development increased to 28 % whereas due to decrease in availability of developable area within the city, the infill developments declined to 9 %. The urban sprawl in Jamnagar city was further characterized on the basis of five dimensions of sprawl viz. population density, continuity, clustering, concentration and centrality by integrating the population data with sprawl for year 2001 and 2011. The study characterised the growth of Jamnagar as low density and low concentration outwardly expansion.
Socio-economic vulnerability and sustainable development in context of Development vs. Conservation debate: A study of Bhagirathi Basin, Uttarakhand, INDIA
Authors:   Nisha, Punia M.
Published: November 2014

Abstract. mountain system bound to have a different path of development owing to its fragile ecological and geological setup. Any drastic and abrupt changes in this system can have repercussion beyond mitigation in form of natural disasters. Remote sensing can play a key role in risk assessment and management, particularly when a few simultaneous reasons coincide, for example, susceptibility to natural disaster and the urban sprawl, spreading over highly vulnerable regions. The present study furnish socioeconomic vulnerability mapping of the Bhagirathi basin through computation of the Socio vulnerability Index (SoVI). SoVI correlates vulnerability to natural or anthropogenic disasters to socio – economic development and illustrates how developmental parameters alter equation of potential effect and recovery in event of a natural catastrophe in the study region. An analytical framework has been imparted to understand possible triggering factors of disasters. Built up area expansion; land use land cover change (LULCC) – deforestation, conversion of forested land into agricultural land and residential settlements, and dam project area; road network development; urbanization; population growth & migration and pilgrimage activities are major drivers which put burden on limited carrying capacity of the natural resources. A guideline for policy making has been presented for an integrated and wholesome development incorporating regional developmental aspiration of the people and ingredients of sustainable development.
Understanding Crop Growing Pattern in Bardhaman district of West Bengal using Multi-Date RISAT 1 MRS data
Authors:   Neetu, Prashnani M. , Singh D. K. , Joshi R. , Ray S. S.
Published: November 2014

Abstract. Information on crop phenology is essential for evaluating crop productivity and crop management. Phenological phases of rice and jute show great inter-annual variability and also large spatial distribution in West Bengal. Hence, it is essential to map the pheonological patterns. In this study spatio-temporal monitoring of the growing pattern of rice and other crops was carried out using multi-date RISAT-1 MRS data in the major rice growing region of Bardhaman district of West Bengal. RISAT-1 provides C band (5.3 Ghz) SAR data. The MRS (Medium Resolution ScanSAR) mode data with HH polarization having spatial resolution of 25 m and swath 115 km was used for this study. Total fifteen sets of MRS SAR data (with repetivity of 25 days) covering a complete year (May, 2013 to April, 2014) was used. Pre-processing of multi-date MRS data included georeferencing, calibration, image-image registration and speckle removal using Lee filter. Groundtruth collected during various cropping seasons (pre-Kharif, Kharif and Rabi) were used to generate crop signature pattern based on which hierarchical decision based models could be formed for classification. The periodic backscatter pattern of different crops and crop sequences were analysed. Accuracy of rice crop classification was higher by using 4-date data, compared to 3-date data. Rice transplanting patterns (Early, Normal and Late), both for Kharif and Rabi, could be identified using multi-date data. Major transplanting period for Kharif Rice was Early August and that of Rabi Rice was Early February.
Evaluation of Partially Overlapping 3D Point Cloud's Registration by using ICP variant and CloudCompare.
Authors: Rajendra Y. D. , Mehrotra S. C. , Kale K. V. , Manza R. R. , Dhumal R. K. , Nagne A. D. , Vibhute A. D.
Published: November 2014

Abstract. Terrestrial Laser Scanners (TLS) are used to get dense point samples of large object’s surface. TLS is new and efficient method to digitize large object or scene. The collected point samples come into different formats and coordinates. Different scans are required to scan large object such as heritage site. Point cloud registration is considered as important task to bring different scans into whole 3D model in one coordinate system. Point clouds can be registered by using one of the three ways or combination of them, Target based, feature extraction, point cloud based. For the present study we have gone through Point Cloud Based registration approach. We have collected partially overlapped 3D Point Cloud data of Department of Computer Science & IT (DCSIT) building located in Dr. Babasaheb Ambedkar Marathwada University, Aurangabad. To get the complete point cloud information of the building we have taken 12 scans, 4 scans for exterior and 8 scans for interior façade data collection. There are various algorithms available in literature, but Iterative Closest Point (ICP) is most dominant algorithms. The various researchers have developed variants of ICP for better registration process. The ICP point cloud registration algorithm is based on the search of pairs of nearest points in a two adjacent scans and calculates the transformation parameters between them, it provides advantage that no artificial target is required for registration process. We studied and implemented three variants Brute Force, KDTree, Partial Matching of ICP algorithm in MATLAB. The result shows that the implemented version of ICP algorithm with its variants gives better result with speed and accuracy of registration as compared with CloudCompare Open Source software.
Monitoring Land Use/Land Cover Changes in a River Basin due to Urbanization using Remote Sensing and GIS Approach
Authors: Shukla S. , Khire M. V. , Gedam S. S.
Published: November 2014

Abstract. Faster pace of urbanization, industrialization, unplanned infrastructure developments and extensive agriculture result in the rapid changes in the Land Use/Land Cover (LU/LC) of the sub-tropical river basins. Study of LU/LC transformations in a river basin is crucial for vulnerability assessment and proper management of the natural resources of a river basin. Remote sensing technology is very promising in mapping the LU/LC distribution of a large region on different spatio-temporal scales. The present study is intended to understand the LU/LC changes in the Upper Bhima river basin due to urbanization using modern geospatial techniques such as remote sensing and GIS. In this study, the Upper Bhima river basin is divided into three adjacent sub-basins: Mula-Mutha sub-basin (ubanized), Bhima sub-basin (semi-urbanized) and Ghod sub-basin (unurbanized). Time series LU/LC maps were prepared for the study area for a period of 1980, 2002 and 2009 using satellite datasets viz. Landsat MSS (October, 1980), Landsat ETM+ (October, 2002) and IRS LISS III (October 2008 and November 2009). All the satellite images were classified into five LU/LC classes viz. built-up lands, agricultural lands, waterbodies, forests and wastelands using supervised classification approach. Post classification change detection method was used to understand the LU/LC changes in the study area. Results reveal that built up lands, waterbodies and agricultural lands are increasing in all the three sub-basins of the study area at the cost of decreasing forests and wastelands. But the change is more drastic in urbanized Mula-Mutha sub-basin compared to the other two sub-basins.
Brief Communication: The effect of submerged vents on probabilistic hazard assessment for tephra fallout
Authors: Tonini R. , Sandri L. , Costa A. , Selva J.
Published: November 2014

Abstract. Many volcanic systems are partially or entirely submerged, implying that vents may open underwater. The effect of submerged vents on probabilistic volcanic hazard assessment (PVHA) for tephra fallout has always been neglected, introducing potentially uncontrolled biases. We present a strategy to quantify the effect of submerged vents on PVHA for tephra fallout, based on a simplified empirical model where the efficiency of tephra production decreases as a function of the water depth above the eruptive vent. The method is then applied to Campi Flegrei caldera, comparing its results to those of two reference end-member models and their statistical mixing.
Correlations between climate network and relief data
Authors: Peron T. K. D. , Comin C. H. , Amancio D. R. , da F. Costa L. , Rodrigues F. A. , Kurths J.
Published: November 2014

Abstract. In the last few years, the scientific community has witnessed an ongoing trend of using ideas developed in the study of complex networks to analyze climate dynamics. This powerful combination, usually called climate networks, can be used to uncover non-trivial patterns of weather changes throughout the years. Here we investigate the temperature network of the North American region and show that two network characteristics, namely degree and clustering, have marked differences between the eastern and western regions. We show that such differences are a reflection of the presence of a large network community on the western side of the continent. Moreover, we provide evidence that this large community is a consequence of the peculiar characteristics of the western relief of North America.
Influence of frontal cyclone evolution on the 2009 (Ekman) and 2010 (Franklin) Loop Current eddy detachment events
Authors: Androulidakis Y. S. , Kourafalou V. H. , Le Hénaff M.
Published: November 2014

Abstract. The anticyclonic Loop Current Eddy (LCE) shedding events are strongly associated with the evolution of Loop Current Frontal Eddies (LCFEs) over the eastern Gulf of Mexico (GoM). A numerical simulation, in tandem with in situ measurements and satellite data, was used to investigate the Loop Current (LC) evolution and the surrounding LCFE formation, structure, growth and migration during the Eddy Ekman and Eddy Franklin shedding events in the summers of 2009 and 2010, respectively. During both events, northern GoM LCFEs appeared vertically coherent to at least 1500 m in temperature observations. They propagated towards the base of the LC, where, together with the migration of Campeche Bank (southwest GoM shelf) eddies from south of the LC, contributed to its "necking-down". Growth of Campeche Bank LCFEs involved in Eddy Franklin was partially attributed to Campeche Bank waters following upwelling events. Slope processes associated with such upwelling included offshore exports of high positive potential vorticity that may trigger cyclone formation and growth. The advection and growth of LCFEs, originating from the northern and southern GoM, and their interaction with the LC over the LCE detachment area favor shedding conditions and may contribute to the final separation of the LCE.