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Climate change resulting from a rapid increase in greenhouse gas (GHG) emissions is adversely affecting humanity. If the GHG emission continues to rise at the current pace, humanity will face severe consequences and reverse all the progress made. This paper, therefore, uses relevant data from 14 developing countries in Asia from 1990 to 2018 to examine the potential impact of environmental innovation on CO2 emissions by controlling globalization, urbanization, and economic growth. The number of environmental-related technology patents is used as a measure of environmental innovation. We employed a panel long-run regression model — FMOLS, PCSE, and FGLS to estimate the elasticity of CO2 emissions. For causal association among variables, we used Dumitrescu-Hurlin Granger causality tests. Our results show that renewable energy consumption and globalization have a significant impact in reducing CO2 emissions, while environmental technology innovations play a meager role in reducing emissions and only when economic growth support those type of investment. Furthermore, we found urbanization, oil consumption, and economic growth is detrimental to the environment, which is also evident in past studies. Therefore, countries should invest in renewable energy and environmental innovation aligned with the growth to reduce GHG emissions. [ABSTRACT FROM AUTHOR]

Economic growth in Asia has increased in the past three decades and has heightened energy demand, resulting in rising greenhouse gas emissions and severe air pollution. To tackle these issues, fuel switching and the deployment of renewables are essential. In the present paper, we discuss the environmental regulations, mainly carbon pricing, implemented in Asia and discuss their achievements. Empirical studies using microdata have shown that carbon pricing in Asia can reduce carbon emissions by promoting energy efficiency. At the macro level, we observe some evidence of fuel switching from coal to natural gas among major emitters. However, more carbon pricing is necessary in Asia if we aim for the decarbonization of the economy. [ABSTRACT FROM AUTHOR]

This paper investigates the impact urbanization, industrialization, corruption, human development, energy consumption, and foreign direct investment (FDI) on carbon dioxide (CO2) emissions of 61 developing economies of the global south region of Asia, Africa, and Latin America during the period 1990–2015. The empirical results show that the effect of corruption on CO2 emissions is indeed heterogeneous and contradictory. Specifically, results exhibit that due to immature economic system, and policy paralysis, corruption penetrates the developing economies, and eventually cause carbon emission and pollution. Furthermore, results reveal that FDI guided by clean development mechanism and involved in emission reduction projects in the developing economies play a predominant role to curb the CO2 emission, pollution, and environmental degradation. [ABSTRACT FROM AUTHOR]

The increase in greenhouse gas concentrations, particularly CO2 , has significant implications for global climate patterns and various aspects of human life. Spaceborne remote sensing satellites play a crucial role in high-resolution monitoring of atmospheric CO2. However, the next generation of greenhouse gas monitoring satellites is expected to face challenges, particularly in terms of computational efficiency in atmospheric CO2 retrieval and analysis. To address these challenges, this study focuses on improving the speed of retrieving the column-averaged dry-air mole fraction of carbon dioxide (XCO2) using spectral data from the Orbiting Carbon Observatory-2 (OCO-2) satellite while still maintaining retrieval accuracy. A novel approach based on neural network (NN) models is proposed to tackle the nonlinear inversion problems associated with XCO2 retrievals. The study employs a data-driven supervised learning method and explores two distinct training strategies. Firstly, training is conducted using experimental data obtained from the inversion of the operational optimization model, which is released as the OCO-2 satellite products. Secondly, training is performed using a simulated dataset generated by an accurate forward calculation model. The inversion performance and prediction performance of the machine learning model for XCO2 are compared, analyzed, and discussed for the observed region over east Asia. The results demonstrate that the model trained on simulated data accurately predicts XCO2 in the target area. Furthermore, when compared to OCO-2 satellite product data, the developed XCO2 retrieval model not only achieves rapid predictions (<1 ms) with good accuracy (1.8 ppm or approximately 0.45 %) but also effectively captures sudden increases in XCO2 plumes near industrial emission sources. The accuracy of the machine learning model retrieval results is validated against reliable data from Total Carbon Column Observing Network (TCCON) sites, demonstrating its ability to effectively capture CO2 seasonal variations and annual growth trends. [ABSTRACT FROM AUTHOR]

This paper analyses Chinese sub-national governments' implementation strategies to meet national energy efficiency targets in the 11th Five-Year Plan (2006-2010). Previous research has focused on the ways governance practices and decision-making structures shape implementation outcomes, yet very little attention has been given to what strategies local leaders actually employ to bridge national priorities with local interests. To illustrate how local leaders work politically, this paper highlights specific implementation methods officials use to strengthen formal incentives and create effective informal incentives to comply with energy efficiency mandates. The analysis is drawn from 53 interviews conducted in June and July of 2010 in Shanxi, a major coal-producing and energy-intensive province. Findings suggest that local government leaders conform to national directives by "bundling" the energy efficiency policy with policies of more pressing local importance or by "bundling" their energy efficiency objectives with the interests of groups with significant political influence. Ultimately, sub-national government officials frame policies in ways that give them legitimacy at the local level. [ABSTRACT FROM AUTHOR]

The article discusses the relation among natural resources, climate change and the growth of Asian economies. Asian countries including China, India and South Korea contributed to the 34% of global greenhouse gas emissions in 2008. China, one of the major carbon emitting countries along with the U.S. and India, attribute its emissions to production of cement and steel. The study adds that sustainable solutions have been developed as responses to climate change including usage of light-emitting diodes, fuel cells and solar cells.

This paper describes a computationally efficient framework for uncertainty studies in global and regional climate change. In this framework, the Massachusetts Institute of Technology (MIT) Integrated Global System Model (IGSM), an integrated assessment model that couples an Earth system model of intermediate complexity to a human activity model, is linked to the National Center for Atmospheric Research (NCAR) Community Atmosphere Model (CAM). Since the MIT IGSM-CAM framework (version 1.0) incorporates a human activity model, it is possible to analyze uncertainties in emissions resulting from both uncertainties in the underlying socio-economic characteristics of the economic model and in the choice of climate-related policies. Another major feature is the flexibility to vary key climate parameters controlling the climate system response to changes in greenhouse gases and aerosols concentrations, e.g., climate sensitivity, ocean heat uptake rate, and strength of the aerosol forcing. The IGSM-CAM is not only able to realistically simulate the present-day mean climate and the observed trends at the global and continental scale, but it also simulates ENSO variability with realistic time scales, seasonality and patterns of SST anomalies, albeit with stronger magnitudes than observed. The IGSM-CAM shares the same general strengths and limitations as the Coupled Model Intercomparison Project Phase 3 (CMIP3) models in simulating present-day annual mean surface temperature and precipitation. Over land, the IGSM-CAM shows similar biases to the NCAR Community Climate System Model (CCSM) version 3, which shares the same atmospheric model. This study also presents 21st century simulations based on two emissions scenarios (unconstrained scenario and stabilization scenario at 660 ppm CO2-equivalent) similar to, respectively, the Representative Concentration Pathways RCP8.5 and RCP4.5 scenarios, and three sets of climate parameters. Results of the simulations with the chosen climate parameters provide a good approximation for the median, and the 5th and 95th percentiles of the probability distribution of 21st century changes in global mean surface air temperature from previous work with the IGSM. Because the IGSM-CAM framework only considers one particular climate model, it cannot be used to assess the structural modeling uncertainty arising from differences in the parameterization suites of climate models. However, comparison of the IGSM-CAM projections with simulations of 31 CMIP5 models under the RCP4.5 and RCP8.5 scenarios show that the range of warming at the continental scale shows very good agreement between the two ensemble simulations, except over Antarctica, where the IGSM-CAM overestimates the warming. This demonstrates that by sampling the climate system response, the IGSM-CAM, even though it relies on one single climate model, can essentially reproduce the range of future continental warming simulated by more than 30 different models. Precipitation changes projected in the IGSM-CAM simulations and the CMIP5 multi-model ensemble both display a large uncertainty at the continental scale. The two ensemble simulations show good agreement over Asia and Europe. However, the ranges of precipitation changes do not overlap - but display similar size - over Africa and South America, two continents where models generally show little agreement in the sign of precipitation changes and where CCSM3 tends to be an outlier. Overall, the IGSM-CAM provides an efficient and consistent framework to explore the large uncertainty in future projections of global and regional climate change associated with uncertainty in the climate response and projected emissions. [ABSTRACT FROM AUTHOR]

• Investigating the sustainability of remarkable GDP growth in emerging economies. • Highlighting the roles of energy and environment in economic growth. • STFP is decomposed to identify the drivers of sustainable development. • Regional disparities are compared by incorporating regional heterogeneities. • Providing implications to promote sustainable development by technology spillover. The remarkable GDP growth along with the dramatic increases in energy consumption and pollution emissions in emerging economies raise the concerns for the sustainability of their development pattern. However, the precise role of how energy and environment contribute to economic growth in emerging economies is still unknown. This paper explores the sustainability of remarkable GDP growth in emerging economies by using non-radial directional distance function (NDDF) to identify the sustainable total-factor productivity (STFP) growth in the emerging economies and comparing it with that in developed economies. Our research extends previous literature by highlighting the roles of energy and environment in economic growth. The results raise the concerns on the sustainability of the remarkable GDP growth (especially after 2000) in emerging economies due to their slow STFP growth after excluding the contributions from energy and environment. Furthermore, it is also found that compared with developed economies, the slower STFP growth in emerging economies is mainly caused by their disadvantages in innovation, although they are able to utilize existing technology by catch-up effect. Besides, analysis from the group heterogeneity among Asia, Eastern Europe and Latin America gives a better grasp of implications for stimulating the sustainable growth in emerging economies by promoting technology spillover from developed economies. [ABSTRACT FROM AUTHOR]

Green growth is deliberated as an effective way for attaining environmental sustainability, but the nexus between fiscal spending and green growth is ignored in highly polluted Asian economies. To fill this gap, this study attempts to investigate the impact of public sector education and research and development expenditures on green economic growth for selected Asian economies for the period 1991–2019. The study employed FMOLS and DOLS methods to assess the association between public expenditures on education and research and development sectors and green economic growth. The study found that education and research and development expenditures both contribute significantly to enhancing green economic growth in most of the selected Asian economies. The study proposed some important policy implications for fostering green economic growth and environmental sustainability by mitigation of pollution emissions. [ABSTRACT FROM AUTHOR]

Emissions of air pollutants and their precursors in urban air closely relate to urbanization involving economic development, population growth, and industrialization. Here we use formaldehyde (HCHO) columns from the TROPOspheric Monitoring Instrument (TROPOMI), night‐time light (NTL) radiance from the Visible Infrared Imaging Radiometer Suite, and population density data as respective proxies to explore how anthropogenic non‐methane volatile organic compound (NMVOC) emissions evolve with urbanization in Asia. HCHO columns correlate moderately to highly (0.64 ≤ r ≤ 0.99) with the NTL radiance within most major Asian countries. On both national (across Asia) and provincial scales (within China), HCHO columns increase monotonically with NTL radiance or population density with a log‐linear pattern, implying anthropogenic NMVOC emissions in Asia may similarly respond to urbanization with no apparent turnover yet. Our study confirms TROPOMI HCHO columns as a proxy of anthropogenic NMVOC emissions. Plain Language Summary: We use multi‐source satellite remote sensing data and population density data to examine how anthropogenic non‐methane volatile organic compound (NMVOC) emissions evolve with urbanization in Asia. Anthropogenic NMVOC emissions (indicated by satellite formaldehyde columns) correlate moderately to highly with urbanization (indicated by night‐time light or population density) within most major Asian countries. We find a monotonic response between anthropogenic NMVOC emissions and urbanization in Asia, with no apparent turnover yet. Key Points: Satellite formaldehyde (HCHO) columns correlate moderately to highly with night‐time light radiance and population density in most major Asian countriesA monotonic response between anthropogenic non‐methane volatile organic compound (NMVOC) emissions and urbanization may exist in Asia, with no apparent turnover yetTROPOspheric Monitoring Instrument HCHO column is confirmed as a reliable proxy of anthropogenic NMVOC emissions in Asia [ABSTRACT FROM AUTHOR]

This study uses annual data to detect the nexus between urbanization, energy use, and carbon emissions in a panel of Association of Southeast Asian Nations (ASEAN) countries spanning the period 1980–2009. The study contributes to the increasing empirical literature by investigating the effects of urbanization and detecting causal links between the variables. Results from the Pedroni panel cointegration tests show evidence for the existence of a long-term equilibrium relationship between urbanization, energy use, and carbon emissions for the ASEAN countries. Using the panel fully modified ordinary least squares technique, the effect of urbanization on carbon emissions is further revealed; i.e., a 1% rise in urban population results in a 0.20% increase in carbon emissions. Unilateral short-run causal relationships from urbanization to energy use and from urbanization to carbon emissions have been found by Granger causality tests. Also, the results clearly indicate that in the long term, urbanization together with energy use Granger causes carbon emissions. The paper concludes with main findings and provides recommendations toward rational planning of urban development and energy-efficiency improvement strategies for the ASEAN countries. [ABSTRACT FROM AUTHOR]

Rapid transport by deep convection is an important mechanism for delivering surface emissions of reactive halocarbons and other trace species to the tropical tropopause layer (TTL), a key region of transport to the stratosphere. Recent model studies have indicated that increased delivery of short-lived halocarbons to the TTL could delay stratospheric ozone recovery. We report here measurements in the TTL over the western Pacific Ocean of short-lived halocarbons and other trace gases that were transported eastward after convective lofting over Asia. Back-trajectories indicate the sampled air primarily originated from the Indian subcontinent. While short-lived organic bromine species show no measurable change over background mixing ratios, short-lived chlorinated organic species were elevated above background mixing ratios (dichloromethane (Δ48.2 ppt), 1,2-dichloroethane (Δ4.21 ppt), and chloroform (Δ4.85 ppt)), as well as longer-lived halogenated species, methyl chloride (Δ82.0 ppt) and methyl bromide (Δ1.91 ppt). This transported air mass thus contributed an excess equivalent effective chlorine burden of 316 ppt, with 119 ppt from short lived chlorinated species, to the TTL. Non-methane hydrocarbons (NMHC) were elevated 60 - 400% above background mixing ratios. The NMHC measurements were used to characterize the potential source regions, which are consistent with the convective influence analysis. The measurements indicate a chemical composition heavily impacted by biofuel/biomass burning and industrial emissions. This work shows that convection can loft Asian emissions, including short-lived chlorocarbons, and transport them to the remote TTL. [ABSTRACT FROM AUTHOR]

Abstract: Greenhouse gas (GHG) emissions from conventional solid waste management in developing Asian countries contribute significantly to global climate change. This paper argues that moving towards Integrated Solid Waste Management (ISWM) offers a practical solution for mitigating these GHG emissions and for realising socio-economic as well as other environmental benefits. The study assesses the GHG emissions of an existing ISWM system in Muangklang Municipality, Thailand as compared to conventional treatment from a life cycle perspective. The integrated system which recovers nutrients, materials and energy from the waste stream, and reduces landfill disposal of organic and recyclable waste was found to have reduced GHG emissions very significantly compared to conventional landfill disposal, which is currently the most common waste treatment technology in Thailand. Among the individual technologies assessed, materials recycling was found to offer the largest reductions in GHG emissions from a life-cycle perspective. The calculations indicate that a properly designed integrated system with high but fully realistic recovery rates can drastically reduce the climate impact of waste management. Most municipalities in developing Asia are small-to-medium scale and share many characteristics with Muangklang. Therefore, the authors argue that most municipalities in the region could apply this type of low-cost locally adapted ISWM system. This would have numerous sustainability benefits, including drastically reduced GHG emissions. [Copyright &y& Elsevier]

Abstract: In this paper, we introduce a new method to estimate the change in mean mixing ratio of a target species at a receptor site due to the contribution of the long-range transport (CLRT). We applied our method to determine inter-annual and inter-seasonal variations in the CLRT of SO2 in Seoul, a major megacity in northeast Asia, during the period from 2001 to 2010. The major potential source areas of SO2 for the 2001–2010 period were located in East China according to the potential source contribution function (PSCF) maps. The CLRT of SO2 in Seoul was estimated to range from 0.40 to 1.03 ppb, which accounted for 8–21% of the ambient mean SO2 mixing ratio in Seoul. The inter-annual variations of estimated CLRT of SO2 was well correlated with those of the total emissions in China during the period of 2001–2008 (R = 0.85). We found that both local emissions from around Seoul and long-range transport from East China, especially the Shandong peninsula, affected the SO2 mixing ratio in Seoul throughout the decade of study. The CLRT of SO2 in Seoul increased after 2007 even though the total emissions of SO2 by China have been decreasing since 2006. The CLRT of SO2 in Seoul was high in spring and winter, which can be attributed to enhanced SO2 emissions in East China during these seasons and a dominant westerly wind. The CLRTs of SO2 accounted for 15, 11, 4, and 12% of the seasonal mean SO2 mixing ratio in spring, summer, fall, and winter, respectively. The uncertainty ranged from 24 to 62% of the estimated CLRT values. [Copyright &y& Elsevier]

Abstract: This paper aims to advance two objectives: (1) identify and explore greenhouse gas emissions from urban areas in Asia at the regional level; and (2) explore covariates of urban greenhouse gas emissions. We use the Emissions Database for Global Atmospheric Research estimates for carbon dioxide, methane, nitrous oxide, and sulfur hexafluoride from 14 source activities for the year 2000, which are allocated on a 1/10° global grid. We extract emissions for 3535 urban extents all with populations over 50,000, accounting for approximately 91% of the region''s urban population. We use regression analysis to associate emissions with urban area and growth, economic, and biophysical characteristics. Our findings suggest that urban areas account for between 30 and 38% of total anthropogenic greenhouse gas emissions for the region and that emission per capita averages from urban areas are lower than those at the national level. Important covariates for total urban greenhouse gas emissions include population size, density and growth rate, income per capita, development status and elevation. This is a first and preliminary assessment of regional baseline trends using these data and this top-down analysis. [Copyright &y& Elsevier]

Abstract: Rather surprisingly, urban atmospheric particulate levels in West Africa compare with measured concentrations in Europe and Asia megacities (Liousse, C., Galy-Lacaux, C., Assamoi, E.-M., Ndiaye, A., Diop, B., Cachier, H., Doumbia, T., Gueye, P., Yoboue, V., Lacaux, J.-P., Guinot, B., Guillaume, B., Rosset, R., Castera, P., Gardrat, E., Zouiten, C., Jambert, C., Diouf, A., Koita, O., Baeza, A., Annesi-Maesano, I., Didier, A., Audry, S., Konare, A., 2009. Integrated Focus on West African Cities (Cotonou, Bamako, Dakar, Ouagadougou, Abidjan, Niamey): Emissions, Air Quality and Health Impacts of Gases and Aerosols. Third International AMMA Conference on Predictability of the West African Moosoon Weather, Climate and Impacts. Ouagadougou, Burkina Faso. July 20–24). This pollution mainly derives from road traffic emissions with, in some capitals (e.g. Cotonou), the strong contribution of two-wheel vehicles. Two key questions arise: are presently available emission inventories (e.g. Junker, C., Liousse, C., 2008. A global emission inventory of carbonaceous aerosol from historic records of fossil fuel and biofuel consumption for the period 1860–1997. Atmospheric Chemistry Physics, 8, 1–13; Bond, T.C., Streets, D.G., Yarber, K.F., Nelson, S.M., Woo, J.H., Klimont, Z., 2004. A technology-based global inventory of black and organic carbon emissions from combustion. Journal of Geophysical Research, 1009, D14203, DOI:10.1029/2003JD003697) able to account for these emissions? And, if not, how can we remedy this? The aim of this paper is to develop a methodology to estimate emissions produced by two-wheel vehicles in West Africa for 2002 in a context where reliable information is hardly available. Fuel consumption ratios between two-wheel engines (in this work) and all vehicles issued from UN database (http://data.un.org/Data.aspx?d=EDATA&f=cmID%3aMO%3btrID%3a1221) are as high as 169%, 264% and 628%, for Burkina Faso, Mali and Chad respectively, indicating that this global database does not properly account for regional specificities. Moreover, emission factors for black carbon (BC) and primary organic carbon (OCp) have been measured for two-stroke engines in Benin (Guinot, B., Liousse, C., Cachier, H., Guillaume, B., et al. New emission factor estimates for biofuels and mobile sources. Atmospheric Environment, in press.), giving significantly higher values than in Europe. This is particularly true for OCp, and consequently the calculated emissions for two-stroke engines are also significantly larger than total road traffic previously estimated in global inventories ( with United Nations database for 2002; ). The ensuing discussion illustrates the importance of two-stroke engines in the West Africa transport sector and the strong need for inventory updating. [Copyright &y& Elsevier]

Results from the Model Intercomparison Study Asia Phase II (MICS-Asia II) are presented. Nine different regional modeling groups simulated chemistry and transport of ozone (O3), secondary aerosol, acid deposition, and associated precursors, using common emissions and boundary conditions derived from a global model. Four-month-long periods, representing 2 years and three seasons (i.e., March, July, and December in 2001, and March in 2002), are analyzed. New observational data, obtained under the EANET (the Acid Deposition Monitoring Network in East Asia) monitoring program, were made available for this study, and these data provide a regional database to compare with model simulations. The analysis focused around seven subject areas: O3 and related precursors, aerosols, acid deposition, global inflow of pollutants and precursor to Asia, model sensitivities to aerosol parameterization, analysis of emission fields, and detailed analyses of individual models, each of which is presented in a companion paper in this issue of Atmospheric Environment. This overview discusses the major findings of the study, as well as information on common emissions, meteorological conditions, and observations. [Copyright &y& Elsevier]

This paper presents key findings of a study conducted under Asian Regional Research Programme in Energy, Environment and Climate on least cost options to meet the projected transport service demand in eight selected Asian cities. It also presents the barriers to the adoption of the selected cleaner transport options. Furthermore, it discusses some policies and measures to promote the cleaner transport options. The study finds that high initial cost and lack of infrastructure (especially for compressed natural gas operated vehicles and mass rapid transit system) are the major barriers to the selected options. [ABSTRACT FROM AUTHOR]

This paper explores the relationship between road infrastructure, economic growth and road CO2 emissions. The basic premise is that many developing nations have achieved sufficient wealth to generate substantial demand for road vehicles, but that actual use is constrained by limited provision of surfaced roads. Our main result is that for comparable levels of income (GDP/capita), CO2 emissions per length of paved road are far higher in rapidly developing Asia as compared to the USA. These findings suggest existence of an 'infrastructure bottleneck', that when relieved, may influence the future trajectory of road transport CO2 emissions in developing Asia. [ABSTRACT FROM AUTHOR]

Abstract: This paper focuses on environmental mercury emissions in Asia and elaborates its probable trend in the future and associated implications given the anticipated socioeconomic outlook and other macro-environmental factors. Among the various regions, Asia has become the largest contributor of anthropogenic atmospheric Hg, responsible for over half of the global emission. In the next few decades, a significant increase in anthropogenic Hg emissions in Asia is likely owing to rapid economic and industrial development, unless drastic measures are taken. In particular, the dominance of Asia in some Hg-emitting industries, such as coal combustion, steel production and gold mining, provokes a serious environmental concern over their potential contributions of incidental Hg in the region. Moreover, the increasing prevalence of electrical and electronic manufacturing industry as a user and a contributor of Hg in Asia is also worrying. Specifically, disposal of obsolete electrical and electronic wastes represents a phenomenon increasingly encountered in Asia. In addition to escalating anthropogenic Hg emissions in Asia, associated environmental and health implications may also exacerbate in the region for the probable effects of a unique combination of climatic (e.g. subtropical climate), environmental (e.g. acid rain) and socioeconomic factors (e.g. high population density). Hence, much effort is still needed to understand the role of Asia in global Hg cycle and associated environmental and health effects in the region. [Copyright &y& Elsevier]

Although Asian economies have registered strong economic growth over the last few decades, their growing pollution emissions raise concerns among the policymakers about the sustainability of this output growth. This paper tests the causal relationship between economic development, energy consumption, trade openness, financial development, FDI, government expenditures, institutional quality. and pollution emissions for 41 Asian economies from 1996 to 2015. Further, we separately test the impact of political and economic institutions on pollution emissions of the sample economies. Our estimated outcomes, based on the panel cointegration method and panel vector error correction models (VECM), substantiate the presence of a cointegration relationship among all the selected variables. While economic development, energy use, trade openness, and FDI augment environmental degradation, financial development and better economic institutions help the selected countries in reducing their pollution emissions. Moreover, better economic and political institutions also mediate the adverse impact of income, trade openness, and FDI on pollution emissions. The VECM model shows that per capita GDP is the only variable having a causal effect on pollution emissions in all the models. For all the other variables, the causal effect is significant only in a few cases. These outcomes have some important policy recommendations for the sample economies. • We test the direct and indirect effect of institutional quality on CO 2 emissions. • Institutional quality contributes to the reduction of CO 2 emissions in Asia. • Institutional quality also moderates the adverse effects of income on CO 2 emissions. • Policy makers should incorporate the role and efficiency of institutional quality. [ABSTRACT FROM AUTHOR]

A long-term historical emission inventory of air and climate pollutants in East, Southeast, and South Asia during 1950–2015 was developed as the Regional Emission inventory in ASia version 3 (REASv3). REASv3 provides details of emissions from major anthropogenic sources for each country and its sub-regions and also provides monthly gridded data with 0.25 ∘ × 0.25 ∘ resolution. The average total emissions in Asia during 1950–1955 and during 2010–2015 (growth rates in these 60 years estimated from the two averages) are as follows: SO 2 : 3.2 Tg, 42.4 Tg (13.1); NO x : 1.6 Tg, 47.3 Tg (29.1); CO: 56.1 Tg, 303 Tg (5.4); non-methane volatile organic compounds: 7.0 Tg, 57.8 Tg (8.3); NH 3 : 8.0 Tg, 31.3 Tg (3.9); CO 2 : 1.1 Pg, 18.6 Pg (16.5) (CO 2 excluding biofuel combustion 0.3 Pg, 16.8 Pg (48.6)); PM 10 : 5.9 Tg, 30.2 Tg (5.1); PM 2.5 : 4.6 Tg, 21.3 Tg (4.6); black carbon: 0.69 Tg, 3.2 Tg (4.7); and organic carbon: 2.5 Tg, 6.6 Tg (2.7). Clearly, all the air pollutant emissions in Asia increased significantly during these 6 decades, but situations were different among countries and regions. Due to China's rapid economic growth in recent years, its relative contribution to emissions in Asia has been the largest. However, most pollutant species reached their peaks by 2015, and the growth rates of other species were found to be reduced or almost zero. On the other hand, air pollutant emissions from India showed an almost continuous increasing trend. As a result, the relative ratio of emissions of India to that of Asia has increased recently. The trend observed in Japan was different from the rest of Asia. In Japan, emissions increased rapidly during the 1950s–1970s, which reflected the economic situation of the period; however, most emissions decreased from their peak values, which were approximately 40 years ago, due to the introduction of control measures for air pollution. Similar features were found in the Republic of Korea and Taiwan. In the case of other Asian countries, air pollutant emissions generally showed an increase along with economic growth and motorization. Trends and spatial distribution of air pollutants in Asia are becoming complicated. Data sets of REASv3, including table of emissions by countries and sub-regions for major sectors and fuel types, and monthly gridded data with 0.25 ∘ × 0.25 ∘ resolution for major source categories are available through the following URL: https://www.nies.go.jp/REAS/index.html (last access: 31 October 2020). [ABSTRACT FROM AUTHOR]

Future air quality will be driven by changes in air pollutant emissions, but also changes in climate. Here, we review the recent literature on future air quality scenarios and projected changes in effects on human health, crops and ecosystems. While there is overlap in the scenarios and models used for future projections of air quality and climate effects on human health and crops, similar efforts have not been widely conducted for ecosystems. Few studies have conducted joint assessments across more than one sector. Improvements in future air quality effects on human health are seen in emission reduction scenarios that are more ambitious than current legislation. Larger impacts result from changing particulate matter (PM) abundances than ozone burdens. Future global health burdens are dominated by changes in the Asian region. Expected future reductions in ozone outside of Asia will allow for increased crop production. Reductions in PM, although associated with much higher uncertainty, could offset some of this benefit. The responses of ecosystems to air pollution and climate change are long-term, complex, and interactive, and vary widely across biomes and over space and time. Air quality and climate policy should be linked or at least considered holistically, and managed as a multi-media problem. This article is part of a discussion meeting issue 'Air quality, past present and future'. [ABSTRACT FROM AUTHOR]

In this work we couple the HTAP_v2.2 global air pollutant emission inventory with the global source receptor model TM5-FASST to evaluate the relative contributions of the major anthropogenic emission sources (power generation, industry, ground transport, residential, agriculture and international shipping) to air quality and human health in 2010. We focus on particulate matter (PM) concentrations because of the relative importance of PM 2.5 emissions in populated areas and the well-documented cumulative negative effects on human health. We estimate that in 2010, depending on the region, annual averaged anthropogenic PM 2.5 concentrations varied between ca. 1 and 40 µ g m -3 , with the highest concentrations observed in China and India, and lower concentrations in Europe and North America. The relative contribution of anthropogenic emission sources to PM 2.5 concentrations varies between the regions. European PM pollution is mainly influenced by the agricultural and residential sectors, while the major contributing sectors to PM pollution in Asia and the emerging economies are the power generation, industrial and residential sectors. We also evaluate the emission sectors and emission regions in which pollution reduction measures would lead to the largest improvement on the overall air quality. We show that air quality improvements would require regional policies, in addition to local- and urban-scale measures, due to the transboundary features of PM pollution. We investigate emission inventory uncertainties and their propagation to PM 2.5 concentrations, in order to identify the most effective strategies to be implemented at sector and regional level to improve emission inventories, knowledge and air quality modelling. We show that the uncertainty of PM concentrations depends not only on the uncertainty of local emission inventories, but also on that of the surrounding regions. Countries with high emission uncertainties are often impacted by the uncertainty of pollution coming from surrounding regions, highlighting the need for effective efforts in improving emissions not only within a region but also from extra-regional sources. Finally, we propagate emission inventory uncertainty to PM concentrations and health impacts. We estimate 2.1 million premature deaths per year with an uncertainty of more than 1 million premature deaths per year due to the uncertainty associated only with the emissions. [ABSTRACT FROM AUTHOR]

Inter-annual variability and long-term trends in tropospheric ozone are both environmental and climate concerns. Ozone measured at Mt Waliguan Observatory (WLG, 3816ma.s.l.) on the Tibetan Plateau over the period of 1994- 2013 has increased significantly by 0.2-0.3 ppbv yr-1 during spring and autumn but shows a much smaller trend in winter and no significant trend in summer. Here we explore the factors driving the observed ozone changes at WLG using backward trajectory analysis, chemistry-climate model hindcast simulations (GFDL AM3), a trajectory-mapped ozonesonde data set, and several climate indices. A stratospheric ozone tracer implemented in GFDL AM3 indicates that stratosphere-to-troposphere transport (STT) can explain ~60% of the simulated springtime ozone increase at WLG, consistent with an increase in the NW air-mass frequency inferred from the trajectory analysis. Enhanced STT associated with the strengthening of the mid-latitude jet stream contributes to the observed high ozone anomalies at WLG during the springs of 1999 and 2012. During autumn, observations at WLG are more heavily influenced by polluted air masses originating from South East Asia than in the other seasons. Rising Asian anthropogenic emissions of ozone precursors are the key driver of increasing autumnal ozone observed at WLG, as supported by the GFDL AM3 model with time-varying emissions, which captures the observed ozone increase (0.26±0.11 ppbv yr-1). AM3 simulates a greater ozone increase of 0.38±0.11 ppbv yr-1 at WLG in autumn under conditions with strong transport from South East Asia and shows no significant ozone trend in autumn when anthropogenic emissions are held constant in time. During summer, WLG is mostly influenced by easterly air masses, but these trajectories do not extend to the polluted regions of eastern China and have decreased significantly over the last 2 decades, which likely explains why summertime ozone measured at WLG shows no significant trend despite ozone increases in eastern China. Analysis of the Trajectory-mapped Ozonesonde data set for the Stratosphere and Troposphere (TOST) and trajectory residence time reveals increases in direct ozone transport from the eastern sector during autumn, which adds to the autumnal ozone increase. We further examine the links of ozone variability at WLG to the quasibiennial oscillation (QBO), the East Asian summer monsoon (EASM), and the sunspot cycle. Our results suggest that the 2-3-, 3-7-, and 11-year periodicities are linked to the QBO, EASM index, and sunspot cycle, respectively. A multivariate regression analysis is performed to quantify the relative contributions of various factors to surface ozone concentrations at WLG. Through an observational and modelling analysis, this study demonstrates the complex relationships between surface ozone at remote locations and its dynamical and chemical influencing factors. [ABSTRACT FROM AUTHOR]

Fuel usage is an important driver of anthropogenic aerosol emissions. In Asia, it is possible that aerosol emissions may increase if business continues as usual, with economic growth driving an increase in coal burning. But it is also possible that emissions may decrease rapidly as a result of the widespread adoption of cleaner technologies or a shift toward noncoal fuels, such as natural gas. In this study, the transient climate impacts of two aerosol emissions scenarios are investigated: a representative concentration pathway 4.5 (RCP4.5) control, which projects a decrease in anthropogenic aerosol emissions, and a scenario with enhanced anthropogenic aerosol emissions from Asia. A coupled atmosphere-ocean configuration of the Community Earth System Model (CESM), including the Community Atmosphere Model, version 5 (CAM5), is used. Three sets of initial conditions are used to produce a three-member ensemble for each scenario. Enhanced Asian aerosol emissions are found to exert a large cooling effect across the Northern Hemisphere, partially offsetting greenhouse gas-induced warming. Aerosol-induced suppression of the East Asian and South Asian summer monsoon precipitation occurs. The enhanced Asian aerosol emissions also remotely impact precipitation in other parts of the world. Over Australia, austral summer monsoon precipitation is enhanced, an effect associated with a southward shift of the intertropical convergence zone, driven by the aerosol-induced cooling of the Northern Hemisphere. Over the Sahel, West African monsoon precipitation is suppressed, likely via a weakening of the West African westerly jet. These results indicate that fuel usage in Asia, through the consequent aerosol emissions and associated radiative effects, might significantly influence future climate both locally and globally. [ABSTRACT FROM AUTHOR]

Due to the scarcity of observational constraints and the rapidly changing environment in East and Southeast Asia, isoprene emissions predicted by models are expected to bear substantial uncertainties. The aim of this study is to improve upon the existing bottom-up estimates, and to investigate the temporal evolution of the fluxes in Asia over 1979- 2012. To this purpose, we calculate the hourly emissions at 0.5° ×0.5° resolution using the MEGAN-MOHYCAN model driven by ECMWF ERA-Interim climatology. In order to remedy for known biases identified in previous studies, and to improve the simulation of interannual variability and trends in emissions, this study incorporates (i) changes in land use, including the rapid expansion of oil palms, (ii) meteorological variability according to ERA-Interim, (iii) long-term changes in solar radiation (dimming/brightening) constrained by surface network radiation measurements, and (iv) recent experimental evidence that South Asian tropical forests are much weaker isoprene emitters than previously assumed, and on the other hand, that oil palms have a strong isoprene emission capacity. These effects lead to a significant lowering (factor of 2) in the total isoprene fluxes over the studied domain, and to emission reductions reaching a factor of 3.5 in Southeast Asia. The bottom-up annual isoprene emissions for 2005 are estimated at 7.0, 4.8, 8.3, and 2.9 Tg in China, India, Indonesia and Malaysia, respectively. The isoprene flux anomaly over the whole domain and studied period is found to be strongly correlated with the Oceanic Niño Index (r = 0.73), with positive (negative) anomalies related to El Niño (La Niña) years. Changes in temperature and solar radiation are the major drivers of the interannual variability and trends in the emissions, except over semi-arid areas such as northwestern China, Pakistan and Kazakhstan, where soil moisture is by far the main cause of interannual emission changes. In our base simulation, annual positive flux trends of 0.2% and 0.52% throughout the entire period are found in Asia and China, respectively, related to a positive trend in temperature and solar radiation. The impact of oil palm expansion in Indonesia and Malaysia is to enhance the trends over that region, e.g., from 1.17%to 1.5%in 1979-2005 in Malaysia. A negative emission trend is derived in India (-0.4%), owing to the negative trend in solar radiation data associated with the strong dimming effect likely due to increasing aerosol loadings. The bottom-up emissions are compared to field campaign measurements in Borneo and South China and further evaluated against top-down isoprene emission estimates constrained by GOME-2/MetOp-A formaldehyde columns through 2007-2012. The satellite-based estimates appear to support our assumptions, and confirm the lower emission rate in tropical forests of Indonesia and Malaysia. Additional flux measurements are clearly needed to characterize the spatial variability of emission factors better. Finally, a decreasing trend in the inferred top-down Chinese emissions since 2007 is in line with recorded cooling in China after that year, thus suggesting that the satellite HCHO columns are able to capture climate-induced changes in emissions. [ABSTRACT FROM AUTHOR]

The Asia–Europe liner service often calls at a number of Europe-continent ports and one UK port. An alternative is to skip the UK port by using feeder services to reach the UK market. This article aims to quantitatively analyze the carbon dioxide (CO2) emissions of these two alternatives, and to identify which is preferable in different scenarios. We adopt a detailed service activity-based method to calculate the CO2 emissions for two alternatives in a range of scenarios. The study is expected to provide shipping companies with useful insight into policy merits and service route design from a CO2 emissions perspective. [ABSTRACT FROM PUBLISHER]

The international agreements, made by International Maritime Organization in 2008 are an encouraging start to reduce the SO2 emissions caused by the use of bunker oil. Port authorities are confronted with a dilemma. From an environmental point of view, a proactive attitude is preferred. However, a unilateral initiative may jeopardize their bunker oil market share. In this article, we study the benefits and drawbacks of collaboration on emissions reduction between the ports of Rotterdam and Singapore. Many options for reducing SO2 emissions and several policies strategies are discussed. Collaboration instead of competition may give a strategic financial advantage as compared to other would-be bunker harbors on the route Europe-Asia. Without a group of dedicated and critical actors, both port authorities do not have the power to enforce policies or options. The Rotterdam system can be regarded as a decentralized multi-actor network. The Singaporean situation may be characterized as a centralized authority. The process design towards cooperation should take into account these differences. Overall, it can be concluded that cooperation between the port authorities of Singapore and Rotterdam has extra benefits compared to a situation without cooperation. [ABSTRACT FROM AUTHOR]

The number of vehicles in China has been increasing rapidly. We evaluate the impact of current and possible future vehicle emissions from China on Asian air quality. We modify the Regional Emission Inventory in Asia (REAS) for China's road transport sector in 2000 using updated Chinese data for the number of vehicles, annual mileage, and emission factors. We develop two scenarios for 2020: a scenario where emission factors remain the same as they were in 2000 (No-Policy, NoPol), and a scenario where Euro 3 vehicle emission standards are applied to all vehicles (except motorcycles and rural vehicles). The Euro 3 scenario is an approximation of what may be the case in 2020 as, starting in 2008, all new vehicles in China (except motorcycles) were required to meet the Euro 3 emission standards. Using the Weather Research and Forecasting model coupled with Chemistry (WRF/Chem), we examine the regional air quality response to China's vehicle emissions in 2000 and in 2020 for the NoPol and Euro 3 scenarios. We evaluate the 2000 model results with observations in Japan, China, Korea, and Russia. Under NoPol in 2020, emissions of carbon monoxide (CO), nitrogen oxides (NOx), non-methane volatile organic compounds (NMVOCs), black carbon (BC), and organic carbon (OC) from China's vehicles more than double compared to the 2000 baseline. If all vehicles meet the Euro 3 regulations in 2020, however, these emissions are reduced by more than 50% relative to NoPol. The implementation of stringent vehicle emission standards leads to a large, simultaneous reduction of the surface ozone (O3) mixing ratios and particulate matter (PM2.5) concentrations. In the Euro 3 scenario, surface O3 is reduced by more than 10 ppbv and surface PM2.5 is reduced by more than 10 µgm-3 relative to NoPol in Northeast China in all seasons. In spring, surface O3 mixing ratios and PM2.5 concentrations in neighboring countries are also reduced by more than 3 ppbv and 1 µgm-3 , respectively. We find that effective regulation of China's road transport sector will be of significant benefit for air quality both within China and across East Asia as well. [ABSTRACT FROM AUTHOR]

The article presents the author'[s view regarding the existence of the atmospheric brown clouds (ABCs) in China and some other regions of Asia. The author describes the composition of the ABC which includes fly ash, smog, and soot and it occurs yearly from December to April, extending its width from the Middle East to the Yellow Sea. In addition, the author denotes that some Asian regions, particularly the East Asia, Southeast Asia, and South Asia. The author cites ABC's difference with the greenhouse gas emissions, where it also blocks the sunlight and cools the temperature. Furthermore, the author asserts that the ABC is the result of human's untoward behavior with nature.

Biomass burning in tropical Asia emits large amounts of trace gases and particulate matter into the atmosphere, which has significant implications for atmospheric chemistry and climatic change. In this study, emissions from open biomass burning over tropical Asia were evaluated during seven fire years from 2000 to 2006 (1 March 2000-31 February 2007). The size of the burned areas was estimated from newly published 1-km L3JRC and 500-m MODIS burned area products (MCD45A1). Available fuel loads and emission factors were assigned to each vegetation type in a GlobCover characterisation map, and fuel moisture content was taken into account when calculating combustion factors. Over the whole period, both burned areas and fire emissions showed clear spatial and seasonal variations. The size of the L3JRC burned areas ranged from 36 031 km2 in fire year 2005 to 52 303 km2 in 2001, and the MCD45A1 burned areas ranged from 54 790 km2 in fire year 2001 to 148 967 km2 in 2004. Comparisons of L3JRC and MCD45A1 burned areas using ground-based measurements and other satellite data were made in several major burning regions, and the results suggest that MCD45A1 generally performed better than L3JRC, although with a certain degree of underestimation in forest areas. The average annual L3JRC-based emissions were 123 (102-152), 12 (9-15), 1.0 (0.7-1.3), 1.9 (1.4-2.6), 0.11 (0.09-0.12), 0.89 (0.63-1.21), 0.043 (0.036-0.053), 0.021 (0.021-0.023), 0.41 (0.34-0.52), 3.4 (2.6-4.3), and 3.6 (2.8-4.7) Tg yr-1 for CO2, CO, CH4, NMHCs, NOx, NH3, SO2, BC, OC, PM2.5, and PM10, respectively, whereas MCD45A1-based emissions were 122 (108-144), 9.3 (7.7-11.7), 0.63 (0.46-0.86), 1.1 (0.8-1.6), 0.11 (0.10-0.13), 0.54 (0.38-0.76), 0.043 (0.038-0.051), 0.033 (0.032-0.037), 0.39 (0.34-0.47), 3.0 (2.6-3.7), and 3.3 (2.8-4.0) Tg yr-1. Forest burning was identified as the major source of the fire emissions due to its high carbon density. Although agricultural burning was the second highest contributor, it is possible that some crop residue combustion was missed by satellite observations. This possibility is supported by comparisons with previously published data, and this result may be due to the small size of the field crop residue burning. Fire emissions were mainly concentrated in Indonesia, India, Myanmar, and Cambodia. Furthermore, the peak in the size of the burned area was generally found in the early fire season, whereas the maximum fire emissions often occurred in the late fire season. [ABSTRACT FROM AUTHOR]

Estimates of Asian emissions of air pollutants and carbonaceous aerosols and their mid-term projections have been changing significantly in the last years. The remote sensing community has shown that increase in NO x in Central East Asia is much stronger than any of the emission inventories or projections indicated so far. A number of studies reviewing older estimates appeared. Here, we review the key contributions and compare them to the most recent results of the GAINS model application for Asia and to the SRES projections used in the IPPC work. The recent projections indicate that the growth of emissions of SO2 in Asia should slow down significantly towards 2010 or even stabilize at the current level. For NO x, however, further growth is projected although it will be most likely slower that in the last decade, owing to introduction of measures in transport. Emissions of carbonaceous aerosols (black carbon and organic carbon) are expected to decline after 2010, largely due to reduced use of biofuels in residential sector and efficiency improvements. The estimates of these emissions are burdened with significantly larger uncertainties than SO2 and NO x; even for the year 2000 the differences in estimates between studies are up to a factor of 2. [ABSTRACT FROM AUTHOR]

Abatement of particulate matter has traditionally been driven by health concerns rather than its role in global warming. Here we assess future abatement strategies in terms of how much they reduce the climate impact of black carbon (BC) and organic carbon (OC) from contained combustion. We develop global scenarios which take into account regional differences in climate impact, costs of abatement and ability to pay, as well as both the direct and indirect (snow-albedo) climate impact of BC and OC. To represent the climate impact, we estimate consistent region-specific values of direct and indirect global warming potential (GWP) and global temperature potential (GTP). The indirect GWP has been estimated using a physical approach and includes the effect of change in albedo from BC deposited on snow. The indirect GWP is highest in the Middle East followed by Russia, Europe and North America, while the total GWP is highest in the Middle East, Africa and South Asia. We conclude that prioritizing emission reductions in Asia represents the most cost-efficient global abatement strategy for BC because Asia is (1) responsible for a large share of total emissions, (2) has lower abatement costs compared to Europe and North America and (3) has large health cobenefits from reduced PM10 emissions. [ABSTRACT FROM AUTHOR]

We used a 3-D model of chemistry and transport to investigate trends and variability in tropospheric carbon monoxide (CO) for 1988-1997 caused by changes in the overhead ozone column, fossil fuel emissions, biomass burning emissions, methane, and transport. We found that the decreasing CO burden in the northern extra-tropics (-0.85%/y) was more heavily influenced by the decrease in European emissions during our study period than by the similar increase in Asian emissions, as transport pathways from Europe favored accumulation at higher latitudes in winter and spring. However, the opposite trends in the CO burdens from these two source regions counterbalanced at lower latitudes. Elsewhere, the factors influencing CO often compete, diminishing their cumulative impact, and trends in model CO were small or insignificant for our study period, except in the tropics in boreal fall (1.1%/y), a result of emissions from major fires in Indonesia late in 1997. There was a decrease in the ozone column during the study period as a result of the phase of the solar cycle and the eruption of Pinatubo in 1991. This decrease contributed negatively to the trend in model CO by increasing the hydroxyl radical (OH). The impact of this negative contribution was diminished by a positive contribution of similar magnitude from increasing methane. However, the trends in these two factors did not cancel for tropospheric OH, which responded primarily to changes in the ozone column. [ABSTRACT FROM AUTHOR]

In recent years the world has moved to a new path of rapid global growth, largely driven by the developing countries, which is energy intensive and heavily reliant on the use of coal—global coal use will rise by nearly 60% over the decade to 2010. It is likely that, without changes to the policies in place in 2006, global CO2 emissions from fuel combustion would nearly double their 2000 level by 2020 and would continue to rise beyond 2030. Neither the SRES marker scenarios nor the reference cases assembled in recent studies using integrated assessment models capture this abrupt shift to rapid growth based on fossil fuels, centred in key Asian countries. While policy changes must and will occur, the realism of the reference case is critical for analysis and policy formulation. Using such a reference path will have significant effects on impact and damage estimates, on the analysis of achievable stabilisation paths and on estimates of the costs of achieving stabilisation at a given GHG concentration level. Use of a realistic reference path is also essential for the international negotiations, arising out of the COP13 meeting in Bali, to achieve widely desired stabilisation goals: both the level of emission reductions to be achieved, and the preferred distribution of those reductions over countries and regions, will be heavily influenced by the reference case assumed. [ABSTRACT FROM AUTHOR]

As part of the model intercomparison study MICS Asia II, the Swedish MATCH model was set up for Southeast and East Asia. In that study, the comprehensive photochemistry scheme of MATCH was used for the first time in Asia. The current work focuses on results of surface ozone from the MATCH model simulations falling outside the model intercomparison study. Model results of surface ozone concentrations for the entire year of 2001 were investigated and compared with measurements in Southeast Asia. The model produced higher surface ozone concentrations than the observations at all of the non-remote stations investigated but underestimated during the dry season at remote locations. Modelled seasonal variation was similar to, but less pronounced than, the variation in the measurements. This study indicates that NO x is the limiting precursor for ozone production in the model, while the fractionation in different species and total amount of non-methane volatile organic compounds (NMVOC) emissions are less important. Naturally emitted NMVOC, isoprene, is an important precursor of surface ozone at certain conditions, and a better inventory of these emissions is needed. Deposition velocities of ozone also have impact on surface concentrations. To improve the model performance, it is important to add a land use inventory with corresponding deposition velocities. [ABSTRACT FROM AUTHOR]

Asia's role in global climate change has evolved significantly from the time when the Kyoto Protocol was being negotiated. Emissions of carbon dioxide, the principal greenhouse gas, from energy use in Asian countries now exceed those from the European Union or North America. Three of the top five emitters—China, India, and Japan, are Asian countries. Any meaningful global effort to address global climate change requires the active cooperation of these and other large Asian countries, if it is to succeed. Issues of equity between countries, within countries, and between generations, need to be tackled. Some quantitative current and historic data to illustrate the difficulties involved are provided, and one approach to making progress is suggested. [ABSTRACT FROM AUTHOR]

The way urbanization unfolds over the next few decades in the developing countries of Asia will have profound implications for sustainability. One of the more important opportunities is to guide urbanization along pathways that begin to uncouple these gains in well-being from rising levels of energy use. Increasing energy use for transport, construction, climate control in houses and offices, and industrial processes is often accompanied by increasing levels of atmospheric emissions that impact human health, ecosystem functions, and the climate system. Agriculture, forestry, and animal husbandry alter carbon stocks and fluxes as carbon dioxide, methane, and black carbon. In this article we explore how carbon management could be integrated into the development strategies of cities and urbanizing regions. In particular, we explore how changes in urban form, functions, and roles might alter the timing, aggregation, spatial distribution, and composition of carbon emissions. Our emphasis is on identifying system linkages and points of leverage. The study draws primarily on emission inventories and regional development histories carried out in the regions around the cities of Manila, Jakarta, Ho Chi Minh City, New Delhi, and Chiang Mai. We find that how urban functions, such as mobility, shelter, and food, are provided has major implications for carbon emissions, and that each function is influenced by urban form and role in distinct ways. Our case studies highlight the need for major "U-turns" in urban policy. [ABSTRACT FROM AUTHOR]

The global impact of shipping on atmospheric chemistry and radiative forcing, as well as the associated uncertainties, have been quantified using an ensemble of ten state-of-the-art atmospheric chemistry models and a predefined set of emission data. The analysis is performed for present-day conditions (year 2000) and for two future ship emission scenarios. In one scenario ship emissions stabilize at 2000 levels; in the other ship emissions increase with a constant annual growth rate of 2.2% up to 2030 (termed the "Constant Growth Scenario" (CGS)). Most other anthropogenic emissions follow the IPCC (Intergovernmental Panel on Climate Change) SRES (Special Report on Emission Scenarios) A2 scenario, while biomass burning and natural emissions remain at year 2000 levels. An intercomparison of the model results with observations over the Northern Hemisphere (25°-60° N) oceanic regions in the lower troposphere showed that the models are capable to reproduce ozone (O3) and nitrogen oxides (NOx=NO+NO2) reasonably well, whereas sulphur dioxide (SO2) in the marine boundary layer is significantly underestimated. The most pronounced changes in annual mean tropospheric NO2 and sulphate columns are simulated over the Baltic and North Seas. Other significant changes occur over the North Atlantic, the Gulf of Mexico and along the main shipping lane from Europe to Asia, across the Red and Arabian Seas. Maximum contributions from shipping to annual mean near-surface O3 are found over the North Atlantic (5-6 ppbv in 2000; up to 8 ppbv in 2030). Ship contributions to tropospheric O3 columns over the North Atlantic and Indian Oceans reach 1 DU in 2000 and up to 1.8 DU in 2030. Tropospheric O3 forcings due to shipping are 9.8±2.0mW/m² in 2000 and 13.6±2.3mW/m² in 2030. Whilst increasing O3, ship NOx simultaneously enhances hydroxyl radicals over the remote ocean, reducing the global methane lifetime by 0.13 yr in 2000, and by up to 0.17 yr in 2030, introducing a negative radiative forcing. The models show future increases in NOx and O3 burden which scale almost linearly with increases in NOx emission totals. Increasing emissions from shipping would significantly counteract the benefits derived from reducing SO2 emissions from all other anthropogenic sources under the A2 scenario over the continents, for example in Europe. Globally, shipping contributes 3% to increases in O3 burden between 2000 and 2030, and 4.5% to increases in sulphate under A2/CGS. However, if future ground based emissions follow a more stringent scenario, the relative importance of ship emissions will increase. Inter-model differences in the simulated O3 contributions from ships are significantly smaller than estimated uncertainties stemming from the ship emission inventory, mainly the ship emission totals, the distribution of the emissions over the globe, and the neglect of ship plume dispersion. [ABSTRACT FROM AUTHOR]