Rajni Dhyani

Emission reduction from MRTS projects – A case study of Delhi metro

Abstract Metro rail has been introduced in Delhi in 2002 to provide alternative mode of public transportation. The introduction of metro rail has resulted in passenger ridership shift from road based transport to metro rail. In order to estimate the emissions (CO, HC, NO x , PM and CO 2 ), metro rail ridership has been converted to equivalent number of on–road vehicles which otherwise would have been playing in the absence of mass rapid transit system. The emission estimation for the year 2006 and 2011 corresponding to the completion of phase I and phase II of Delhi metro rail has been made using emission and deterioration factor(s) for different category and vintage of vehicles. The sensitivity analysis has been carried out to assess the influence of different combination of input parameters such as modal shift, engine technology, and fuel type on emissions. In addition, CO 2 emissions saved due to shifting of motor vehicle ridership to metro rail has been estimated and compared with the CO 2 produced (off–site) due to electricity consumption by Delhi metro rail for its various operations. The findings indicate that present modal shift scenario does not yield CO 2 benefits. However, it is expected that with the increase in metro ridership, changes in modal shift and energy conservation initiatives by Delhi metro, CO 2 emission saving could be possible.

Sensitivity Analysis of CALINE4 Model under Mix Traffic Conditions

ABSTRACTHighway dispersion models are routinely used for prediction of air quality along road and highway corridors. Various input parameters used by these models for prediction of air quality along the road corridors. In the present study, sensitivity analysis of CALINE4 model was carried out under mixed traffic conditions to identify the input parameters and the extent to which they influence the output (i.e., predicted concentration) of the model. The road corridor selected in Delhi city (India) was a stretch of National Highway-2 (NH-2) passing through the city. The selected corridor caters to both inter-city and intra-city traffic and had mixed traffic conditions. Carbon monoxide was selected as indicator pollutant for prediction and sensitivity analysis exercise. Sensitivity analysis of the CALINE4 model was carried out for three hours input datasets representing different meteorological (wind speed, wind direction, mixing height, stability class), traffic (traffic volume and emission factors) and road characteristic (roadway width) along with terrain (surface roughness) characteristic. Input parameters corresponding to selected datasets were varied separately and systematically and their impact on predicted CO concentrations was observed and quantified. It was observed that apart from source strength (traffic volume and emission factors), meteorological parameters viz., wind speed and wind direction influenced the prediction capabilities of model considerably. Whereas, surface roughness, mixing height had relatively less contribution in models output.

Performance evaluation of CALINE 4 model in a hilly terrain – a case study of highway corridors in Himachal Pradesh (India)

CALINE 4 highway dispersion model is extensively used all over the world including India for prediction of vehicular pollution along highway corridors. A few studies have reported its application and suitability under complex/hilly terrain. In the present paper, an attempt has been made to evaluate the performance of CALINE 4 model in hilly terrain for Indian traffic and meteorological conditions. CALINE 4 model predictions have been compared between flat and hilly terrains along two road corridors in Solan District in the state of Himachal Pradesh (India). The statistical indicators of the model performance such as, index of agreement (d), fractional bias (FB), and normalised mean square error (NMSE) reveal that the model performed satisfactorily in the flat terrain. However, model fell short in explaining the complexity of terrain and performed unsatisfactorily in hilly terrain conditions.

Critical Issues Related to Metro Rail Projects in India

Rail-based ‘Mass Rapid Transit System’ has been widely accepted as a solution for most of the traffic and environmental pollution related problems which major cities throughout the world are facing now. Metro rail construction activities are being undertaken in a big way in India, existing metro rail network of the city of Kolkata and Delhi are being expanded, while it is under various stages of construction in cities like Bengaluru, Chennai, Mumbai and Hyderabad. In the present article, important environmental and other critical issues have been discussed in the Indian context which are equally relevant in other developing counties.

Meteorological Factors Influencing Dispersion of Vehicular Pollution in a Typical Highway Condition

Vehicular dispersion models, particularly highway dispersion models are used worldwide, including India, for assessment and management of air quality along the major roads/highways. However, dispersion of vehicular pollutants is influenced by various factors such as traffic, receptors and land use along with meteorological factors. In the present study, CALINE4, a Gaussian-based vehicular pollution dispersion model has been used in Delhi, along Ring Road Corridor near Indraprastha Park. Sensitivity analysis of CALINE4 model has been carried out for identification and quantification of meteorological parameters, viz. wind speed, wind direction, mixing height and P–G stability class influencing the model’s output. These input parameters in the model were systematically varied for assessing their influence on model’s output, i.e. predicted concentrations. The study revealed that wind speed and wind directions have significant impact on dispersion of vehicular pollutants as compared to mixing height and stability class.

Challenges of small protected areas in urban cities: a case study of Okhla Bird Sanctuary, India

Protected areas have been earmarked throughout the world for the purpose of conserving the biodiversity. The protected areas are facing serious threats due to rapid urban growth, especially in the developing countries like India. The current threats and impacts of urbanization on the Okhla Bird Sanctuary (Delhi, India) have been presented in this paper as a case in point. Uncontrolled urbanization and the lack of policy implementation have been identified as one of the major contributors to incessant biodiversity loss in India and other countries. In addition, a possible management framework for a smaller protected area in an urban setting is presented in brief.