HTAP_v2.2: a mosaic of regional and global emission grid maps for 2008 and 2010 to study hemispheric transport of air pollution

Abstract

Abstract. The mandate of the Task Force Hemispheric Transport of Air Pollution (TF HTAP) under the Convention on Long-Range Transboundary Air Pollution (CLRTAP) is to improve the scientific understanding of the intercontinental air pollution transport, to quantify impacts on human health, vegetation and climate, to identify emission mitigation options across the regions of the Northern Hemisphere, and to guide future policies on these aspects. The harmonization and improvement of regional emission inventories is imperative to obtain consolidated estimates on the formation of global-scale air pollution. An emissions data set has been constructed using regional emission grid maps (annual and monthly) for SO2, NOx, CO, NMVOC, NH3, PM10, PM2.5, BC and OC for the years 2008 and 2010, with the purpose of providing consistent information to global and regional scale modelling efforts. This compilation of different regional gridded inventories – including that of the Environmental Protection Agency (EPA) for USA, the EPA and Environment Canada (for Canada), the European Monitoring and Evaluation Programme (EMEP) and Netherlands Organisation for Applied Scientific Research (TNO) for Europe, and the Model Inter-comparison Study for Asia (MICS-Asia III) for China, India and other Asian countries – was gap-filled with the emission grid maps of the Emissions Database for Global Atmospheric Research (EDGARv4.3) for the rest of the world (mainly South America, Africa, Russia and Oceania). Emissions from seven main categories of human activities (power, industry, residential, agriculture, ground transport, aviation and shipping) were estimated and spatially distributed on a common grid of 0.1° × 0.1° longitude-latitude, to yield monthly, global, sector-specific grid maps for each substance and year. The HTAP_v2.2 air pollutant grid maps are considered to combine latest available regional information within a complete global data set. The disaggregation by sectors, high spatial and temporal resolution and detailed information on the data sources and references used will provide the user the required transparency. Because HTAP_v2.2 contains primarily official and/or widely used regional emission grid maps, it can be recommended as a global baseline emission inventory, which is regionally accepted as a reference and from which different scenarios assessing emission reduction policies at a global scale could start. An analysis of country-specific implied emission factors shows a large difference between industrialised countries and developing countries for acidifying gaseous air pollutant emissions (SO2 and NOx) from the energy and industry sectors. This is not observed for the particulate matter emissions (PM10, PM2.5), which show large differences between countries in the residential sector instead. The per capita emissions of all world countries, classified from low to high income, reveal an increase in level and in variation for gaseous acidifying pollutants, but not for aerosols. For aerosols, an opposite trend is apparent with higher per capita emissions of particulate matter for low income countries.

Impacts of Different Characterizations of Large-Scale Background on Simulated Regional-Scale Ozone Over the Continental United States

“…These simulations leveraged the coordinated AQMEII3/HTAP2 modeling experiments (Galmarini et al, 2017;Huang et al, 2017). In particular, all of these alternative global simulations providing boundary conditions (as well as the C-IFS simulations providing boundary conditions for BASE) utilized the same global anthropogenic emission inventory described in Janssens-Maenhout et al (2015) that is consistent with the regional-scale 20 inventory used in the CMAQ simulations and described by Pouliot et al (2015).…”

“…Significant positive ozone biases at CASTNET sites in the SE were also reported for GEOSChem for summer 2013 by Travis et al (2016) who attributed a large portion of the bias to overestimated anthropogenic NOx emissions. In the current study, the annual total anthropogenic NOx emissions are shared across all regional and large-scale simulations since the HTAP2 global inventory (Janssens-Maenhout et al, 2015) incorporated the AQMEII2 regional inventory (Pouliot et al, 2015) over North America, although differences may exist in terms of temporally and vertically allocating these 20 emissions for a specific model. This suggest that factors other than anthropogenic emissions, such as biogenic emissions, chemistry, and deposition that differ between the large-scale models as well as between the large-scale models and regional CMAQ also affect the ozone bias in this region.…”

“…The 2010 annual simulations analyzed in this study were performed with version 5.0.2 of the CMAQ model (Byun and Schere, 2006) using meteorological fields prepared with version 3.4 of the Weather Research and Forecasting (WRF) model (Skamarock and Klemp, 2007) and emission inputs described in Pouliot et al (2015). The CMAQ simulations were performed with a horizontal grid spacing of 12 km over the continental U.S. and used 35 vertical layers extending to 50mb.…”

Impacts of air pollutants from fire and non-fire emissions on the regional air quality in Southeast Asia

“…As mentioned before, Philip et al (2017) have pointed out that global atmospheric models can produce a 2-16 µg m −3 underestimation in fine particulate mass concentration across East and South Asia and most current global emission inventories indeed either do not include anthropogenic fugitive and industrial dusts or substantially underestimate the quantities of these emissions (Klimont et al, 2016;Janssens-Maenhout et al, 2015). The fugitive dust sources, such as road and construction dust, in most major cities in Southeast Asia are apparently not well represented in the emission inventory used in our study.…”

Global anthropogenic emissions of particulate matter including black carbon

“…In fact, the only global set where PM 10 , PM 2.5 , BC, and OC were published is the so-called "mosaic inventory" developed within the UNECE Task Force on Hemispheric Transboundary Air Pollution (HTAP), where a compilation of EDGAR and several regional inventories was put together (Janssens-Maenhout et al, 2015) for 2010. For most of the species the HTAP_v2 is lower than ECLIPSE V5a by about 20-30 % except OC, where the agreement is good (Table S8.1).…”