Developing synergy regression models with space-borne ALOS PALSAR and Landsat TM sensors for retrieving tropical forest biomass     

Suman Sinha  C Jeganathan  L K Sharma  M S Nathawat  Anup K Das  Shiv Mohan 《Journal of Earth System Science》2016,125(4):725-735

Forest stand biomass serves as an effective indicator for monitoring REDD (reducing emissions from deforestation and forest degradation). Optical remote sensing data have been widely used to derive forest biophysical parameters inspite of their poor sensitivity towards the forest properties. Microwave remote sensing provides a better alternative owing to its inherent ability to penetrate the forest vegetation. This study aims at developing optimal regression models for retrieving forest above-ground bole biomass (AGBB) utilising optical data from Landsat TM and microwave data from L-band of ALOS PALSAR data over Indian subcontinental tropical deciduous mixed forests located in Munger (Bihar, India). Spatial biomass models were developed. The results using Landsat TM showed poor correlation (R² = 0.295 and RMSE = 35 t/ha) when compared to HH polarized L-band SAR (R² = 0.868 and RMSE = 16.06 t/ha). However, the prediction model performed even better when both the optical and SAR were used simultaneously (R² = 0.892 and RMSE = 14.08 t/ha). The addition of TM metrics has positively contributed in improving PALSAR estimates of forest biomass. Hence, the study recommends the combined use of both optical and SAR sensors for better assessment of stand biomass with significant contribution towards operational forestry.  相似文献   

Trend analysis of rainfall time series for Sindh river basin in India   总被引：1，自引：1，他引：0  

Sarita Gajbhiye  Chandrashekhar Meshram  Rasoul Mirabbasi  S. K. Sharma 《Theoretical and Applied Climatology》2016,123(3-4):593-617

The main goal of this paper is to estimate a set of optimal seasonal, daily, and hourly values of atmospheric turbidity and surface radiative parameters Ångström’s turbidity coefficient (β), Ångström’s wavelength exponent (α), aerosol single scattering albedo (ω_o), forward scatterance (F_c) and average surface albedo (ρ_g), using the Brute Force multidimensional minimization method to minimize the difference between measured and simulated solar irradiance components, expressed as cost functions. In order to simulate the components of short-wave solar irradiance (direct, diffuse and global) for clear sky conditions, incidents on a horizontal surface in the Metropolitan Area of Rio de Janeiro (MARJ), Brazil (22° 51′ 27″ S, 43° 13′ 58″ W), we use two parameterized broadband solar irradiance models, called CPCR2 and Iqbal C, based on synoptic information. The meteorological variables such as precipitable water (u_w) and ozone concentration (u_o) required by the broadband solar models were obtained from moderate-resolution imaging spectroradiometer (MODIS) sensor on Terra and Aqua NASA platforms. For the implementation and validation processes, we use global and diffuse solar irradiance data measured by the radiometric platform of LabMiM, located in the north area of the MARJ. The data were measured between the years 2010 and 2012 at 1-min intervals. The performance of solar irradiance models using optimal parameters was evaluated with several quantitative statistical indicators and a subset of measured solar irradiance data. Some daily results for Ångström’s wavelength exponent α were compared with Ångström’s parameter (440–870 nm) values obtained by aerosol robotic network (AERONET) for 11 days, showing an acceptable level of agreement. Results for Ångström’s turbidity coefficient β, associated with the amount of aerosols in the atmosphere, show a seasonal pattern according with increased precipitation during summer months (December–February) in the MARJ.  相似文献   

Characterization and radiative impact of dust aerosols over northwestern part of India: a case study during a severe dust storm     

Atinderpal Singh  Shani Tiwari  Deepti Sharma  Darshan Singh  Suresh Tiwari  Atul Kumar Srivastava  Neeraj Rastogi  A. K. Singh 《Meteorology and Atmospheric Physics》2016,128(6):779-792

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Modelling long-term HFC emissions from India's residential air-conditioning sector: exploring implications of alternative refrigerants,best practices,and a sustainable lifestyle within an integrated assessment modelling framework     

Vaibhav Chaturvedi  Mohit Sharma 《Climate Policy》2016,16(7):877-893

India's growing role in the global climate debate makes it imperative to analyse emission reduction policies and strategies across a range of GHGs, especially for under-researched non-CO₂ gases. Hydrofluorocarbons' (HFCs) usage in cooling equipment and subsequent emissions are expected to increase dramatically in India with the phase-out of hydrochlorofluorocarbons (HCFCs) as coolants in air-conditioning equipment. We focus on the residential air-conditioning sector in India and analyse a suite of HFC and alternative coolant gas scenarios for understanding the implications for GHG emissions from this sector within an integrated assessment modelling framework. We find that, if unabated, HFC410A emissions will contribute to 36% of the total global warming impact from the residential air-conditioner sector in India in 2050, irrespective of the future economic growth trajectory, and the remaining 64% is from energy to power residential air-conditioners. A move towards more efficient, low global warming potential (GWP) alternative refrigerants will significantly reduce the cumulative global warming footprint of this sector by 37% during the period 2010–2050, due to gains both from energy efficiency as well as low GWP alternatives. Best practices for reducing direct emissions are important, but only of limited utility, and if a sustainable lifestyle is adopted by consumers with lower floorspace, low GWP refrigerants, and higher building envelope efficiencies, cumulative emissions during 2010–2050 can be reduced by 46% compared to the Reference scenario.

Policy relevance

Our analysis has important implications for Indian climate policy. We highlight that the Indian government's amendment proposal to the Montreal Protocol is a strong signal to the Indian market that the transition away from high GWP refrigerants towards low/zero GWP alternatives will happen sooner or later. The Bureau of Energy Efficiency should extend building energy conservation code policy to residential buildings immediately, and the government should mandate it. Government authorities should set guidelines and mandate reporting of data related to air-conditioner coolant recharge frequency and recovery of scrapped air-conditioner units. For contentious issues like flammability where there is no consensus within the industry, the government needs to undertake an independent technical assessment that can provide unbiased and reliable information to the market.  相似文献   

Texture Measurement Through Local Pattern Quantization for SAR Image Classification     

Debasish Chakraborty  Dibyendu Dutta  Jaswant Raj Sharma 《Journal of the Indian Society of Remote Sensing》2016,44(3):471-477

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Estimation of the source parameters of the Nepal earthquake from strong motion data     

A. Joshi  Monu Tomer  Sohan Lal  Sumer Chopra  Sandeep Singh  Sanjay Prajapati  M. L. Sharma  Sandeep 《Natural Hazards》2016,83(2):867-883

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A study of characteristics of ground motion response spectra from earthquakes recorded in NE Himalayan region: an active plate boundary     

Babita Sharma  Sumer Chopra  P. Chingtham  Vikas Kumar 《Natural Hazards》2016,84(3):2195-2210

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Hydrologic testing during drilling: application of the flowing fluid electrical conductivity (FFEC) logging method to drilling of a deep borehole     

Chin-Fu Tsang  Jan-Erik Rosberg  Prabhakar Sharma  Theo Berthet  Christopher Juhlin  Auli Niemi 《Hydrogeology Journal》2016,24(6):1333-1341

Drilling of a deep borehole does not normally allow for hydrologic testing during the drilling period. It is only done when drilling experiences a large loss (or high return) of drilling fluid due to penetration of a large-transmissivity zone. The paper proposes the possibility of conducting flowing fluid electrical conductivity (FFEC) logging during the drilling period, with negligible impact on the drilling schedule, yet providing important information on depth locations of both high- and low-transmissivity zones and their hydraulic properties. The information can be used to guide downhole fluid sampling and post-drilling detailed testing of the borehole. The method has been applied to the drilling of a 2,500-m borehole at Åre, central Sweden, firstly when the drilling reached 1,600 m, and then when the drilling reached the target depth of 2,500 m. Results unveil eight hydraulically active zones from 300 m down to borehole bottom, with depths determined to within the order of a meter. Further, the first set of data allows the estimation of hydraulic transmissivity values of the six hydraulically conductive zones found from 300 to 1,600 m, which are very low and range over one order of magnitude.  相似文献   

The Housing Market and Population Vulnerabilities: Perceptions in a Fordist and a Post‐Fordist Context          下载免费PDF全文

Madhuri Sharma 《Geographical review》2016,106(4):588-613

Drawing on qualitative interviews and participatory urban‐appraisal tools, this paper analyzes household perceptions on the five elements of Lawrence and Su‐Yeul's market‐led pluralism (M‐LP) framework (2008). It uses post‐Fordist Columbus, Ohio, and Fordist Milwaukee, Wisconsin, as testing grounds for these household perspectives. M‐LP suggests that at the center of contemporary housing market lie five elements: developers/builders who unveil new urban spaces with culturally open communities; lending agencies that offer affordable mortgages to all; real estate brokers/agents who have moved past discriminatory practices; consumers whose preferences emphasize class‐type elements; and communities that impose development agendas. While many felt that the housing market of the mid‐2000s was racially blind, race still played a crucial role in driving home‐buying decisions, especially in Milwaukee. Columbus respondents aligned more closely with M‐LP, putting greater emphasis on class, but they also used phrases and words to blur race and class distinction. Both metropolises, though, illustrated complex intertwining between class and culture.  相似文献   

Utilization of electrocoagulation-treated spent wash sludge in making building blocks     

P. Sharma  H. Joshi 《International Journal of Environmental Science and Technology》2016,13(1):349-358

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