Abstract
Abstract. Substantial changes in anthropogenic aerosols and precursor gas emissions have occurred over recent decades due to the implementation of air pollution control legislation and economic growth. The response of atmospheric aerosols to these changes and the impact on climate are poorly constrained, particularly in studies using detailed aerosol chemistry–climate models. Here we compare the HadGEM3-UKCA (Hadley Centre Global Environment Model-United Kingdom Chemistry and Aerosols) coupled chemistry–climate model for the period 1960–2009 against extensive ground-based observations of sulfate aerosol mass (1978–2009), total suspended particle matter (SPM, 1978–1998), PM10 (1997–2009), aerosol optical depth (AOD, 2000–2009), aerosol size distributions (2008–2009) and surface solar radiation (SSR, 1960–2009) over Europe. The model underestimates observed sulfate aerosol mass (normalised mean bias factor (NMBF) = −0.4), SPM (NMBF = −0.9), PM10 (NMBF = −0.2), aerosol number concentrations (N30 NMBF = −0.85; N50 NMBF = −0.65; and N100 NMBF = −0.96) and AOD (NMBF = −0.01) but slightly overpredicts SSR (NMBF = 0.02). Trends in aerosol over the observational period are well simulated by the model, with observed (simulated) changes in sulfate of −68 % (−78 %), SPM of −42 % (−20 %), PM10 of −9 % (−8 %) and AOD of −11 % (−14 %). Discrepancies in the magnitude of simulated aerosol mass do not affect the ability of the model to reproduce the observed SSR trends. The positive change in observed European SSR (5 %) during 1990–2009 ("brightening") is better reproduced by the model when aerosol radiative effects (ARE) are included (3 %), compared to simulations where ARE are excluded (0.2 %). The simulated top-of-the-atmosphere aerosol radiative forcing over Europe under all-sky conditions increased by > 3.0 W m−2 during the period 1970–2009 in response to changes in anthropogenic emissions and aerosol concentrations.
Highlights
Aerosols can cause acid deposition, degradation of atmospheric visibility, changes to Earth’s radiative balance, and are a major source of air pollution, which affects human health
We evaluate the ability of the model to consistently capture observed changes in bulk in situ aerosol properties (PM, aerosol size distributions and chemical components) as well as radiative properties (AOD, surface solar radiation (SSR)) over Europe
The simulated temporal trends were evaluated by comparing against observed trends; if the gradient of the simulated and observed trends are within ± two standard error (SE) of each other we considered them to be similar
Summary
Aerosols can cause acid deposition, degradation of atmospheric visibility, changes to Earth’s radiative balance, and are a major source of air pollution, which affects human health. Aerosols interact with climate by absorbing and reflecting incoming solar radiation and by modifying the microphysical properties of clouds. These effects have been defined in the latest Intergovernmental Panel on Climate Change (IPCC) report (Boucher et al, 2013) as aerosol– radiation interactions (ARI) and aerosol–cloud interactions (ACI). Aerosols ( referred to as particulate matter (PM)) are detrimental to air quality and human health, as particles below a certain size can penetrate into the lungs causing respiratory and cardiovascular problems (COMEAP, 2010). Turnock et al.: Modelled and observed changes in European aerosols 1960–2009 induce both benefits and penalties for either depending on the particular species targeted (Arneth et al, 2009; Ramanathan and Feng, 2009; Fiore et al, 2012)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
