1,188 research outputs found
How do variations in Urban Heat Islands in space and time influence household water use? The case of Phoenix, Arizona
No full textabstract: This paper explores how urbanization, through its role in the evolution of Urban Heat Island (UHI), affects residential water consumption. Using longitudinal data and drawing on a mesoscale atmospheric model, we examine how variations in surface temperature at the census tract level have affected water use in single family residences in Phoenix, Arizona. Results show that each Fahrenheit rise in nighttime temperature increases water consumption by 1.4%. This temperature effect is found to vary significantly with lot size and pool size. The study provides insights into the links between urban form and water use, through the dynamics of UHI.Corresponding Author:
Rimjhim M. Aggarwal
Arizona State University
[email protected]
Role of development policies in combating climate change issues in Indian agriculture: A first order assessment of irrigation and fertilizer policies
No full textThe Government of India has pursued policies supporting intensive use of irrigation and fertilizer for the development of agrarian economy. A first order assessment of the impacts of these development policies on mitigation, adaptation, resilience and sustainability has been made quantitatively with the help of specific performance indicators. The analysis is based on the hypothesis that productivity enhancement serves better to deal with climate change as it minimizes deforestation and therefore reduces intensification of greenhouse gas emissions. The assessment establishes that development policies have been highly successful in reducing potential greenhouse gas intensification and increasing the adaptation capacity in terms of food grain production. The performance of policies, particularly of water resources development, with respect to sustainability is, however, questionable. The relatively new initiative on micro irrigation fares well in respect of most performance indicators, calling for further policy support for its scaling out. Joshi, Pramod K.; Aggarwal, P.K.; Tyagi, N.K.; Pandey, Divy
Caste, religion and power: an Indian case study
No full textReviews the book "Caste, Religion and Power: An Indian Case Study," by Pratap C. Aggarwal.; Reviews the book "Caste, Religion and Power: An Indian Case Study," by Pratap C. Aggarwal
Data mining : the textbook / Charu C. Aggarwal.
No full textcomputer bookfair2016Includes bibliographical references and index.xxix, 734 pages
Managing Climatic Risks to Combat Land Degradation and Enhance Food security: Key Information Needs
No full textThis paper discusses the key information needs to reduce the negative impacts of weather variability and climate change on land degradation and food security, and identifies the opportunities and barriers between the information and services needed. It suggests that vulnerability assessments based on a livelihood concept that includes climate information and key socio-economic variables can overcome the narrow focus of common one-dimensional vulnerability studies. Both current and future climatic risks can be managed better if there is appropriate policy and institutional support together with technological interventions to address the complexities of multiple risks that agriculture has to face. This would require effective partnerships among agencies dealing with meteorological and hydrological services, agricultural research, land degradation and food security issues. In addition a state-of-the-art infrastructure to measure, record, store and disseminate data on weather variables, and access to weather and seasonal climate forecasts at desired spatial and temporal scales would be needed
The use of SARAL/AltiKa altimeter measurements for multi-site hydrodynamic model validation and rating curves estimation: An application to Brahmaputra River
No full textHydrodynamic (HD) modelling in data sparse region represents a challenge due to poor hydrological and topographic data availability. Recently, remote sensing techniques offer additional data that may help to improve the reliability and accuracy of such analysis. In this study, an attempt has been made to investigate the potential and added value of altimeter measurements for multi-site validation of the HD model and constructed rating curves (RCs) in a sparsely gauged Brahmaputra River, India. The HD model (MIKE 11) was developed for a Brahmaputra River stretch of 135 km, between Tezpur and Guwahati, where 4 ground-tracks of the SARAL/AltiKa (the first Ka band altimeter mission) cross the river. The Nash Sutcliffe efficiency (NSE) between HD model based water level and in-situ water level during calibration (January-October 2013) and validation (January-March 2014) was found to be 0.93 and 0.79 respectively. Calibrated and validated HD model was used to simulate water level and build rating curves at virtual stations. The bias correction (7.2 cm to 9.5 cm) was applied to the altimetry measurements before comparison with the modelled water levels. The root mean square error (RMSE) ranging between 15 cm and 42 cm was observed between the modelled and altimetry-derived water level at all the virtual stations, indicating the potential of satellite altimetry for multi-site validation of the HD model (inline with previous studies) and validation of the constructed RCs. The availability of RCs at virtual stations allows the expansion of the gauging network along the Brahmaputra River, thus enabling the estimation of the discharge at additional locations and the potential evaluation of the contributions of lateral tributaries could be evaluated in future work
Decoding "Public authority" under the RTI act: a comment on Subhash Chandra Aggarwal v. Indian national congress
No full textThe June, 2013 order of the Central Information Commission ("CIC") in Subhash Chandra Aggarwal v. Indian National Congress which brought political parties within the scope of the Right to Information ("RTI") Act, has highlighted some issues regarding the drafting and interpretation of the RTI Act. The CIC held that the six national political parties which were respondents
in the case, have the ingredients that qualify them as "public authorities" within the meaning of section 2(h) of the RTI Act. In this comment the author argues that the reasoning for holding what constitutes substantial financing that makes a body a "public authority" is not clear and the interpretation of the definition of "public authority" is inconsisten
Impact of tariff reduction on exports: A quantitative assessment of Indian exports to US
No full textThis paper quantitatively assesses likely changes in market access opportunities for Indian exports owing to tariff reductions by the USA. The study identifies particular products for India at the ISIC 4-digit level of disaggregation, which could be considered tariff sensitive. Regression analysis of the relationship between MFN tariff rates and India's exports to the US was used to assess in quantitative terms the likely impact of tariff reduction that may be agreed in the Doha Round. This analysis suggests that tariff cuts are not expected to benefit India's exports to the US in a major way. With the full implementation of the Chairman's formula for tariff cuts, increase in India's exports to the US would amount to 1.2 or 0.6 depending on the value of the B coefficient in theChairman's formula. These findings are in all likelihood substantially due to the tariff diversion effect of NAFTA preferences in favour of suppliers in Mexico, which is a competing country in many traditional items. It is expected that reduction of MFN tariff would alleviate the trade diversion effect of the NAFTA.The study has also attempted to decompose changes in India's total exports due to tariff reductions in the US into the competitive and market effects. The analysis suggests that the increase in India's exports would be mainly due to the competitive effect. This leads the author to conclude that it is crucial for India to improve its competitiveness vis-a-vis its competitors in different markets.
Modeling long-term dynamics of carbon and nitrogen in intensive rice-based cropping systems in the Indo-Gangetic Plains (India)
No full textSoil organic matter (SOM) is an essential component of any sustainable crop production system, both as a nutrient source for the crop and a physical conditioner for the soil. Land use systems based on (flooded) rice- aerobic upland crop rotations, with their annual cycles of wet and dry soil conditions, puddling and plowing, are unique in their influence on SOM dynamics. Recent reports have related yield 'stagnation' in rice-wheat systems in parts of the Indo-Gangetic Plains (IGP) to a decline in SOM quantity and quality. For exploration of the long-term effects of intensive cultivation on soil C and N dynamics, and the consequences for crop yields, a summary model has been developed, based on insights in the underlying processes, to investigate the role of soil organic matter in yield formation in rice-based cropping systems in the IGP and to identify possible reasons for declining yields in the region.Following a review of existing SOM models with emphasis on approaches and principles, to identify processes relevant for long-term dynamics of C and N in rice-based cropping systems, the different components of the systems (SOM and crop) were investigated. A simple analytical model (Yang's model) used to analyze soil carbon balances for different sites in the IGP, showed that carbon demand to maintain soil organic carbon (SOC) levels depends on their initial level, and SOC dynamics are governed by crop performance, determining the rate of carbon input into a soil, and the carbon input through organic amendments. A crop growth model (LINTUL3) was developed describing crop growth of rice for N-limited situations. Nitrogen stress in the model is quantified through the nitrogen nutrition index, a measure of relative crop (leaf and stem) nitrogen content. Subsequently, the knowledge was integrated into a summary model, comprising three modules: a soil organic matter (SOM) module, a soil (SOIL) module, and a crop growth (CROP) module. SOM in the model comprises three pools: fresh, labile and stable. Carbon and nitrogen dynamics in the model are described in terms of carbon turnover, assimilation and dissimilation, with nitrogen linked through distinct C/N ratios. Turnover of fresh SOM depends on substrate composition. Maximum relative turnover rates of the labile and stable pools are pool-specific and actual rates are influenced by environmental (temperature, moisture, texture, pH) and management (tillage and puddling) factors. Data sets of nine long-term experiments from the IGP of India were used to calibrate and validate the model. In general, the model satisfactorily reproduced observed crop yields, SOC dynamics and total soil N dynamics for various cropping systems at different sites. With recommended fertilizer NPK applications, a significant decline in yield was found only at two sites: Ludhiana-3 and Pantnagar. Nitrogen mineralized from soil organic matter contributed 20-80% to total N uptake for different treatments. The model results show that an increase in SOM is not always associated with an increase in yield, as the factor(s) improved by an increase in SOM may not be the limiting factor for crop growth. The study concludes that SOM is not always a direct measure of a soil's nitrogen supplying capacity and the importance of SOM as a nutrient source for the crop depends on the relative contribution of other N sources. This suggests that SOM dynamics are not the sole reason for observed yield stagnation
- …
