Aircraft emission mitigation by changing route altitude: A multi-model estimate of aircraft NOx emission impact on O3 photochemistry

The atmospheric impact of aircraft NOx emissions are studied using updated aircraft inventories for the year 2006, in order to estimate the photochemistry-related mitigation potential of shifting cruise altitudes higher or lower by 2000 ft. Applying three chemistry-transport models (CTM) and two climatechemistry models (CCM) in CTM mode, all including detailed tropospheric and stratospheric chemistry, we estimate the short-lived radiative forcing (RF) from O3 to range between 16.4 and 23.5 mW m 2, with a mean value of 19.5 mW m 2. Including the long-lived RF caused by changes in CH4, the total NOxrelated RF is estimated to about 5 mW m 2, ranging 1e8 mW m 2. Cruising at 2000 ft higher altitude increases the total RF due to aircraft NOx emissions by 2 ± 1 mW m 2, while cruising at 2000 ft lower altitude reduces RF by 2 ± 1 mWm 2. This change is mainly controlled by short-lived O3 and show that chemical NOx impact of contrail avoiding measures is likely small

Bambusa multiplex

Angiosperm

Approaches to low carbon development in China and India

Low carbon development has gained policy prominence and is a concern of both environment and development policy globally and in China and India. This paper discusses the role of China and India as important global actors in light of development imperatives in the two countries. The article then looks at emerging approaches in the two countries related to financing, science, technology & innovation policy, and sub-national actions. The objective is to review efforts in China and India for contributing to learning experiences for other countries. The final section discussed the ways forward in terms of examining the role of China and India in terms of national policy strengthening as well as in global agenda setting. Implementation of sub-national initiatives in both countries faces challenges due to lack of adequate financing as well as knowledge such as greenhouse gas inventories and disaggregated resource and socio-economic assessments. Both India and China are making efforts in technology and innovation domains to set foot on a trajectory of low carbon development with varying degrees of success. In finance, both China and India have experimented with various instruments—the key difference is that China has taken the support of regulation more while India has leaned on to market based instruments. Both China and India are moving on an encouraging track regarding low carbon development with fairly well-designed domestic policies and consistent international engagement