Satoru Chatani

National Institute for Environmental Studies · Center for Regional Environmental Research

We have developed a framework for a three-dimensional regional air quality simulation that is applicable to various air quality studies over Japan. The framework consists of the following simulation model systems: the Weather Research and Forecasting (WRF) model to simulate meteorological fields; the Community Multi-scale Air Quality (CMAQ) modelin...

A regional air quality simulation framework including the Weather Research and Forecasting modelling system (WRF), the Community Multi-scale Air Quality modeling system (CMAQ), and precursor emissions to simulate tropospheric ozone over South and East Asia is introduced. Concentrations of tropospheric ozone and related species simulated by the fram...

The inter-comparison of regional air quality models is an effective way to understand uncertainty in ambient pollutant concentrations simulated using various model configurations, as well as to find ways to improve model performance. Based on the outcomes and experiences of Japanese projects thus far, a new model inter-comparison project called Jap...

Source sensitivity and source apportionment are two major indicators representing source–receptor relationships, which serve as essential information when considering effective strategies to accomplish improved air quality. This study evaluated source sensitivities and apportionments of ambient ozone and PM2.5 concentrations over Japan with multipl...

It has been reported that ambient ozone concentrations in Japan have not been effectively suppressed by precursor emission controls. In this study, we developed an unprecedented long-term emission inventory of ozone precursors, including nitrogen oxide (NOX) and volatile organic compounds (VOCs), in Japan. The developed emission inventory, which ex...

The MIXv2 Asian emission inventory is developed under the framework of the Model Inter-Comparison Study for Asia (MICS-Asia) Phase IV and produced from a mosaic of up-to-date regional emission inventories. We estimated the emissions for anthropogenic and biomass burning sources covering 23 countries and regions in East, Southeast and South Asia and...

The MIXv2 Asian emission inventory is developed under the framework of the Model Inter-Comparison Study for Asia (MICS-Asia) Phase IV, and produced from a mosaic of up-to-date regional emission inventories. We estimated the emissions for anthropogenic and biomass burning sources covering 23 countries and regions in East, Southeast and South Asia, a...

This study aims to understand the impact of previous air quality improvement policies on historical emission changes by examining long-term emission trends in Korea. Annual emissions from 2000 to 2018 were estimated using Korea’s official emissions inventory, the Clean Air Policy Support System (CAPSS). To ensure a consistent comparison, standardiz...

Tropospheric ozone threatens human health and crop yields, exacerbates global warming, and fundamentally changes atmospheric chemistry. Evidence has pointed toward widespread ozone increases in the tropo-sphere, and particularly surface ozone is chemically complex and difficult to abate. Despite past successes in some regions, a solution to new cha...

Organic aerosol (OA) is a dominant component of PM2.5, and accurate knowledge of its sources is critical for identification of cost-effective measures to reduce PM2.5. For accurate source apportionment of OA, we conducted field measurements of organic tracers at three sites (one urban, one suburban, and one forest) in the Tokyo Metropolitan Area an...

This study, performed under the umbrella of the Task Force on Hemispheric Transport of Air Pollution (TF-HTAP), responds to the global and regional atmospheric modelling community's need of a mosaic emission inventory of air pollutants that conforms to specific requirements: global coverage, long time series, spatially distributed emissions with hi...

For evaluating reductions of automobile emissions by the regulations, automobile emissions of CO, NOx and HC were estimated from 2000 to 2019. The estimated emissions were compared with emissions in the case of constant emission factors equivalent to the long-term regulation established before 2000 and analyzed for the annual trend with forecasted...

This study, performed under the umbrella of the Task Force on Hemispheric Transport of Air Pollution (TF-HTAP), responds to the need of the global and regional atmospheric modelling community of having a mosaic emission inventory of air pollutants that conforms to specific requirements: global coverage, long time series, spatially distributed emiss...

A high-resolution (1 km × 1 km) emission inventory was developed for Hanoi for 2017 and 2018. The total annual emissions of PM2.5, BC, OC, NOx, SO2, NMVOC, NH3, CH4, and CO were 14.9, 1.6, 2.9, 56.7, 19.1, 109.2, 23.0, 37.9, and 472.7 Gg, respectively. Transportation, industry, and agriculture contributed 89.1%, 92.2%, and 81.3% to the total emissi...

In Japan, the achievement rate of environmental standards for air pollution has been improving in recent years, but for photochemical oxidants, including ozone, improvement are required. In this study, we investigated trends in ozone countermeasures in the United States and Europe from the State Implementation Plan (SIP) and National Air Pollution...

To mitigate tropospheric ozone (O3) pollution with proper and effective emission regulations, diagnostics for the O3-sensitive regime are critical. In this study, we analyzed the satellite-measured formaldehyde (HCHO) and nitrogen dioxide (NO2) column densities and derived the HCHO to NO2 ratio (FNR) from 2005 to 2019. Over China, there was a clear...

Treatment of condensable particulate matter (CPM) is key for accurate simulation of atmospheric particulate matter (PM), because emission surveys of conventional stationary combustion sources do not measure CPM in many countries. This study updates previously estimated CPM emissions from stationary combustion sources in Japan by considering the rel...

For source apportionment by tracer method of secondary organic aerosol (SOA), the ratios of aerosol tracer to total SOA mass (fSOA) were determined during the oxidation of toluene, naphthalene, α-pinene, and isoprene by a series of laboratory experiments. Seven anthropogenic SOA tracers maintaining an aromatic ring structure, including 4-nitrophtha...

The ambient concentrations of individual VOC species were observed at five locations in Tokyo for two days in every season from autumn 2019 to summer 2020. The issues regarding air quality simulations and emission inventories were investigated by comparing the observed and simulated concentrations of the individual VOC species. Alkanes and ketones...

Worldwide exposure to ambient PM2.5 causes over 4 million premature deaths annually. As most of these deaths are in developing countries, without internationally coordinated efforts this polarized situation will continue. As yet, however, no studies have quantified nation-to-nation consumer responsibility for global mortality due to both primary an...

Sulfate aerosol (SO4²⁻) is a main component of particulate matter in Asian countries. Accurate numerical modeling is important for appropriate policy-making aimed at reducing SO4²⁻ concentrations. The modeling performance for SO4²⁻ is superior among aerosol components, however, current models underestimate SO4²⁻ concentrations during winter over As...

Continuous monitoring of hourly PM2.5 component concentrations has been performed in Japan. The objective of this study was to evaluate the advantages of continuous monitoring to obtain data that can be useful for regional air quality simulations. Inclusion of transboundary transport in the simulations improved the correlation between the observed...

Economic development, transport demand, and air pollution are interrelated. The heterogeneity of economic development among regions and the freezing of exhaust emission regulations for approximately a decade in Thailand were the motivations for this study. Herein we provide a comprehensive analysis of vehicle exhaust emission projections for up to...

In 2015, El Niño contributed to severe droughts in equatorial Asia (EA). The severe droughts enhanced fire activity in the dry season (June–November), leading to massive fire emissions of CO2 and aerosols. Based on large event attribution ensembles of the MIROC5 atmospheric global climate model, we suggest that historical anthropogenic warming incr...

In this study, the results for nitrate (NO3−) aerosol during winter from the first-phase model inter-comparison study of Japan’s Study for Reference Air Quality Modeling (J-STREAM) were analyzed. To investigate the models’ external and internal settings, the results were limited to Community Multiscale Air Quality (CMAQ) models. All submitted model...

Abstract. Source sensitivity and source apportionment are two major indicators representing source-receptor relationships, which serve as essential information when considering effective strategies to accomplish improved air quality. This study evaluated source sensitivities to and apportionments of ambient ozone and PM_2.5 concentrations...

A model inter-comparison of secondary pollutant simulations over urban areas in Japan, the first phase of Japan’s study for reference air quality modeling (J-STREAM Phase I), was conducted using 32 model settings. Simulated hourly concentrations of nitric oxide (NO) and nitrogen dioxide (NO2), which are primary pollutant precursors of particulate m...

Ozone is one of remaining air quality issues in Japan. Effective strategies are required to reduce ozone at the ground level. Regional chemical transport models are useful in investigating relationships between precursor emissions and ambient concentrations of secondary pollutants including ozone. Model performance on ozone concentrations over urba...

This research sets out to quantify the mortality and economic loss in individual Asian countries caused by the PM2.5 emissions induced by the consumption of the world's five highest-consuming countries (US, China, Japan, Germany, UK). In 2010 alone, the economic impact of these five countries' consumption caused a loss of almost 45 billion US dolla...

During the Japanese intercomparison study, Japan’s Study for Reference Air Quality Modeling (J-STREAM), it was found that wintertime SO42– concentrations were underestimated over Japan with the Community Multiscale Air Quality (CMAQ) modeling system. Previously, following two development phases, model performance was improved by refining the Fe- an...

In 2015, El Niño caused severe droughts in equatorial Asia (EA). The severe droughts enhanced fire activities in the dry seasons, leading to massive fire emissions of CO2 and aerosols. Using large event attribution ensembles of the MIROC5 atmospheric global climate model, we suggest that historical anthropogenic warming increased the chances of met...

Bottom-up CH4 emission inventories, which have been developed from statistical analyses of activity data and country specific emission factors (EFs), have high uncertainty in terms of the estimations, according to results from top-down inverse model studies. This study aimed to determine the causes of overestimation in CH4 bottom-up emission invent...

Sulfate aerosol (SO42−) is a major component of particulate matter in Japan. The Japanese model intercomparison study, J-STREAM, found that although SO42− is well captured by models, it is underestimated during winter. In the first phase of J-STREAM, we refined the Fe- and Mn-catalyzed oxidation and partly improved the underestimation. The winter h...

Uncertainty was evaluated in four chemical mechanisms pertaining to O3 concentrations predicted over Japan by the Community Multiscale Air Quality Model (CMAQ) to investigate factors contributing to model overestimation of O3 concentration. The model setting and meteorological and emissions input data were obtained from a Japanese model inter-compa...

Because emission rates of particulate matter (PM) from stationary combustion sources have been measured without dilution or cooling in Japan, condensable PM has not been included in Japanese emission inventories. In this study, we modified an emission inventory to include condensable PM from stationary combustion sources based on the recent emissio...

The urban model inter-comparison study (UMICS) was conducted in order to improve the performance of air quality models (AQMs) for simulating fine particulate matter (PM2.5) in the Greater Tokyo Area of Japan. UMICS consists of three phases: the first phase focusing on elemental carbon (UMICS1), the second phase focusing on sulfate, nitrate and ammo...

Many places in India suffer from severe air pollution. Regional air quality simulations are essential to develop effective strategies for improving air quality, considering the non‐linear relationships between ambient pollutants and their precursor emissions. Meteorological fields used in simulations are derived from regional meteorological models...

Regional air quality simulations provide powerful tools for clarifying mechanisms of heavy air pollution and for considering effective strategies for better air quality. This study introduces a new vegetation database for Japan, which could provide inputs for regional meteorological modeling, and estimating emissions of biogenic volatile organic co...

We refined the aqueous-phase sulfate (SO4²⁻) production in the state-of-the-art Community Multiscale Air Quality (CMAQ) model during the Japanese model inter-comparison project, known as Japan's Study for Reference Air Quality Modeling (J-STREAM). In Japan, SO4²⁻ is the major component of PM2.5, and CMAQ reproduces the observed seasonal variation o...

Bangkok Metropolitan Region (BMR), including the capital city and five adjacent provinces, constitutes one of the top 10 megacities experiencing serious traffic congestion in the world, leading to air quality problems with significant adverse human health risks. Previously, there have been many operations planned to influence the fuel consumption a...

Bangkok Metropolitan Region (BMR), including the capital city and five adjacent provinces, constitutes one of the top 10 megacities experiencing serious traffic congestion in the world, leading to air quality problems with significant adverse human health risks. Previously, there have been many operations planned to influence the fuel consumption a...

This study reports the frequency of open burning, which was observed in two ways in Tsukuba-city, Ibaraki prefecture. First, the daily frequency between September and October, 2015, showed that the quantity increased before rainfall and that the rice residues, 57% of the total open burning, were burned in the order of hulls, then straw after harves...

Ground level ozone is emerging as a pollutant of concern in India. Limited surface monitoring data reveals that ozone concentrations are well above the prescribed national standards. This study aims to simulate the regional and urban scale ozone concentrations in India using WRF-CMAQ models. Sector-specific emission inventories are prepared for the...

O3 is created by the reaction of OH and trace species in the atmosphere. The reactions are related to the anthropogenic and biogenic VOCs. Biogenic VOCs (BVOC) are measured as well as anthropogenic VOCs, and many kinds of BVOC measurements have been reported. The number of reports of BVOCs emitted from Sugi (Cryptomeria japonica) is limited, becaus...

A method to distribute the temporal emission in a thermal power plant, which is expected to improve the accuracy of the air pollution forecasting system, has been developed. A linear multiple regression formula, which estimates the hourly electric supply and demand energy in the future and which is based on the month, day of the week, clock time an...

A new gridded database has been developed to estimate the amount of isoprene, monoterpene, and sesquiterpene emitted from all the broadleaf and coniferous trees in Japan with the Model of Emissions of Gases and Aerosols from Nature (MEGAN). This database reflects the vegetation specific to Japan more accurately than existing ones. It estimates much...

This paper presents a new inventory of NMVOC emissions from anthropogenic sources in India for the year 2010. The main new element of this inventory, compared to previous work for India, is the use of new and more detailed data on solvent use sectors and oil production and distribution system. The results are presented at the national and state lev...

Unlabelled: Improvement of air quality models is required so that they can be utilized to design effective control strategies for fine particulate matter (PM2.5). The Community Multiscale Air Quality modeling system was applied to the Greater Tokyo Area of Japan in winter 2010 and summer 2011. The model results were compared with observed concentr...

A regional air quality simulation framework including the Weather Research and Forecasting modelling system (WRF), the Community Multi-scale Air Quality modeling system (CMAQ), and precursor emissions to simulate tropospheric ozone over South and East Asia is introduced. Concentrations of tropospheric ozone and related species simulated by the fram...

Air quality simulation models are important tools for setting regulatory policy. A combination of Meso-scale Model MM5 and Community Multi-scale 3-D Air Quality model system was applied to the studied domain which included Bangalore city and surrounding regions, where NO2 concentrations were predicted. Emissions estimated for different sectors and...

The first phase of the Urban air quality Model InterComparison Study in Japan (UMICS) has been conducted to find ways to improve model performance with regard to elemental carbon (EC). Common meteorology and emission datasets are used with eight different models. All the models underestimate the EC concentrations observed in Tokyo Metropolitan Area...

In Northeast Asia, the effect of long-range transport of air pollutants is generally pronounced in spring and winter, but can be important even in summer. This study analyzed summer-time atmospheric transport of elemental carbon (EC) and sulfate (SO42−) with the Community Multiscale Air Quality (CMAQ) model driven by the Weather Research and Foreca...

The mean NO2/NOx ratios of vehicle emission, the mean duration time of NO reaction with O3 and background concentrations at the five most polluted roadside stations in Tokyo are estimated statistically using monitoring data at both roadside sites and urban background sites. These statistics are then used to categorize roadside NO2 into three compon...

Isoprene is a reactive volatile organic compound (VOC), the annual global biogenic emissions of which are the largest of the non-methane VOC. Since isoprene emissions are partly temperature-driven, understanding the relationship between isoprene emission and climate must be improved. Isoprene emission was measured in Quercus crispula, the second-mo...

We have developed a regional scale air quality simulation using the Weather Research and Forecasting (WRF) – Community Multiscale Air Quality Model (CMAQ) to assess the suitability of such an advanced modeling system for predicting the air quality of Bangladesh and its surrounding region. The Regional Emission Inventory in Asia (REAS) was used as t...

We have conducted a comprehensive observational study to determine the mixing ratios of atmospheric chemical species and total OH reactivity in central Tokyo, in order to diagnose the air quality during summer and winter 2007 and autumn 2009. Concentrations of over 70 reactive trace species were continuously measured throughout each season. The tot...

Reactive volatile organic compounds (VOCs) are known to affect atmospheric chemistry. Biogenic VOCs (BVOCs) have a significant impact on regional air quality due to their large emission rates and high reactivities. Diterpenes (most particularly, kaur-16-ene) were detected in all of the 205 enclosure air samples collected over multiple seasons at tw...

An integrated emission inventory of China was validated through comparing the Community Multi-scale Air Quality (CMAQ) simulations with the NO2 and SO2 column retrieved from Ozone Monitoring Instrument (OMI), Aerosol Optical Depth (AOD) retrieved from Moderate Resolution Imaging Spectroradiometer (MODIS), and ground observations of SO2, NO2, PM10,...

Air quality simulations in which the global chemical transport model CHASER and the regional chemical transport model WRF/chem are coupled have been developed to consider the dynamic transport of chemical species across the boundaries of the domain of the regional chemical transport model. The simulation captures the overall seasonal variations of...

Reactive volatile organic compounds (VOCs) are known to affect atmospheric chemistry, especially biogenic VOCs (BVOCs) which have a significant impact on regional air quality due to their large emission rates and high reactivities. Diterpenes (Kaur-16-ene and a diterpene likely to be Hibaene) were detected in all of the 205 enclosure air samples co...

A three-dimensional air quality simulation was conducted to analyze the sensitivities of the emission sources and transboundary transport on PM2.5 concentrations in three major Japanese urban areas for the year 2005. The sensitivities of the emission sources were derived from the differences in the concentrations in two simulation cases in which th...

Non-methane hydrocarbons (NMHCs) are known to have an important role on air quality due to their high reactivity. NMHC analysis has been performed on 148 ambient air samples collected at five different sites in the Kanto area (Tokyo metropolitan area and surrounding six prefectures) of Japan in summer and winter of 2008, and fifty NMHCs have been d...

Inter-comparison of chemical transport models (CTMs) was conducted among four modeling research groups. Model performance of the ensemble approach to O3 and PM2.5 simulation was evaluated by using observational data with a time resolution of 1 or 6 hours at four sites in the Kanto area, Japan, in summer 2007. All groups applied the Community Multis...

Inter-comparison of chemical transport models (CTMs) was conducted among four modeling research groups. Model performance of the ensemble approach to O3 and PM2.5 simulation was evaluated by using observational data with a time resolution of 1 or 6 hours at four sites in the Kanto area, Japan, in summer 2007. All groups applied the Community Multis...