10th International Aerosol Conference September 2 - September 7, 2018 America's Center Convention Complex St. Louis, Missouri, USA
Abstract View
Evolution of PM Components in Europe over the 1990-2010 Period in the Framework of the Eurodelta-Trends Exercise
GIANCARLO CIARELLI, Augustin Colette, Matthias Beekmann, Mark Theobald, Peter Wind, Camilla Andersson, Florian Couvidat, Astrid Manders-Groot, Mihaela Mircea, Maria Teresa Pay, Valentin Raffort, Svetlana Tsyro, Kees Cuvelier, Mario Adani, Bertrand Bessagnet, Robert Bergstrom, Gino Briganti, Andrea Cappelletti, Massimo D’isidoro, Hilde Fagerli, Yelva Roustan, Marta Vivanco, LISA
Abstract Number: 1304 Working Group: Aerosol Modeling
Abstract Recent studies have investigated the changes in particulate matter (PM) concentrations over the past decades in Europe. However, only a few have investigated the evolution of the individual PM components, i.e. inorganic and organic phases, following the implementation of emission reduction strategies. The trends in PM components might differ as a result of the different chemical regimes in different European regions and the non-linear response of PM to changes in precursor emissions. Thus, understanding how the chemical composition of PM has varied during the last decades could provide more insight for future air quality legislation.
In the framework of the EURODELTA-Trends (EDT) modeling exercise, several Chemical Transport Models (CTMs) were applied for the 1990–2010 period in order to investigate air quality changes in Europe due to the implementation of emission reduction strategies. A common anthropogenic emission dataset was used by the modeling teams (i.e. NO2, SO2, HN3 and non-methane VOCs) based on estimates from the Greenhouse gases and Air pollution Interactions and Synergies (GAINS) model. Model simulations were conducted at 0.25° and 0.4° resolution in latitude and longitude, respectively, with a domain extent from 17° W to 39.8° E and from 32° S to 70° N. Five CTMs have provided air quality estimates for a 21 year period (i.e. CHIMERE, EMEP/MSC-W , MATCH, LOTOS-EUROS and MINNI).
For this study, we combined consolidated long-term air quality measurements of sulfate (SO42-), total nitrate (TNO3), total ammonium (TNH4), as well as sulfur dioxide (SO2) and nitrogen dioxide (NO2) available for multiple sites in Europe for the 1990–2010 period with output data from the CTMs used in the EDT exercise.
Comparisons between modeled and measured data showed a relatively good agreement between the model ensemble and the measured data. In particular, the faster decline in SO2 and SO42- concentrations in the first decade analyzed (1990–2000) compared with the second one (2000–2010) was well captured by the model ensemble. For TNO3 and TNH4 concentrations, both the measurements and the model ensemble showed rather flat trends for both periods, with larger differences in trend significance occurring at a single station level. The evolution of the modeled secondary organic aerosol (SOA) concentrations were also investigated together with the trends in emissions of biogenic volatile organic compound (VOCs). For the models that provided biogenic emission data, a statistically significant increase in biogenic emissions (i.e. isoprene and monoterpene) was found along with an increase in the relative contribution of biogenic SOA (B-SOA) to the total SOA.
In addition, modeled SOA concentrations were evaluated against positive matrix factorization (PMF) data available during the second decade. Results indicated a systematic under-estimation of the modeled SOA fraction with large differences between the models, most likely due to the different levels of complexity of the SOA schemes.