Anthropogenic aerosol emissions lead to an increase in the amount of cloud condensation nuclei and consequently an increase in cloud droplet number concentration and cloud albedo. The corresponding negative radiative forcing due to aerosol cloud interactions (RFaci) is one of the most uncertain radiative forcing terms as reported in the 5th Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). Here we show that previous observation-based studies underestimate aerosol-cloud interactions because they used measurements of aerosol optical properties that are not directly related to cloud formation and are hampered by measurement uncertainties. We have overcome this problem by the use of new polarimetric satellite retrievals of the relevant aerosol properties (aerosol number, size, shape). The resulting estimate of RFaci = −1.14 Wm 2 (range between −0.84 and −1.72 Wm 2) is more than a factor 2 stronger than the IPCC estimate that includes also other aerosol induced changes in cloud properties.

Atmospheric haze, which builds up over South Africa including our study areas, Cape Town and the Mpumalanga Highveld under calm weather conditions, causes public concern. The scope of this study was to determine the concentration and composition of atmospheric aerosol at Khayelitsha (an urban site in the Western Cape) and Ferrobank (an industrial site in Witbank, Mpumalanga). Particulate matter was collected in Khayelitsha from 18 May 2007 to 20 July 2007 (i.e. 20 samples) using a Partisol-plus sampler and a Tapered Element Oscillating Microbalance (TEOM) sampler. Sampling took place at Ferrobank from 07 February 2008 to 11 March 2008 (6 samples) using a Partisol-plus sampler and an E-sampler. The gravimetric mass of each exposed sample was determined from pre- and post-sampling weighing. The elemental composition of the particulate matter was determined for 16 elements at Khayelitsha using Proton Induced X-ray Emission (PIXE). The concentration of the elements Al, Si, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Cu, Zn, As, Br, Sn, and Pb was determined by analysing the PIXE spectra obtained. In similar manner, the elemental composition of the particulate matter was determined for 15 elements at Ferrobank (Al, Si, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Cu, Zn, As, Br and Pb). The average aerosol mass concentrations for different days at the Khayelitsha site were found to vary between 8.5 μg/m3 and 124.38 μg/m3. At the Khayelitsha site on three occasions during the sampling campaign the average aerosol mass concentrations exceeded the current South African air quality standard of 75 μg/m3 over 24 h. At the Ferrobank site, there are no single days that exceeded the limit of the South African air quality standard during the sampling campaign. Enrichment factors for each element of the particles sampled with an aerodynamic diameter of less than 10 μm (PM10) samples have been calculated in order to identify their possible sources. The analysis yielded five potential sources of PM10 : soil dust, sea salt, gasoline emissions, domestic wood and coal combustion. Interestingly, enrichment factor values for the Khayelitsha samples show that sea salt constitutes a major source of emissions, while Ferrobank samples, the source apportionment by unique ratios (SPUR) indicate soil dust and coal emission are the major sources of pollution. The source apportionment at Khayelitsha shows that sea salt and biomass burning are major source of air pollution.

People spend major part of their life indoors – at home or in other public or private indoor environments. Clean air in the living environment is very important for the public health. Indoor air quality (IAQ) is largely dependent on the outdoor air quality, due to the continuous indoor air mixing with the ambient air. However, air pollutants in buildings are strongly linked to building indoor factors as well (emissions from building structure, fabrics, coating, furnishing, ventilation system, food preparation, occupant activities etc.). Building renovation is mostly based on economic aspects – performing cost-effective refurbishment actions assuming further savings in energy costs, without taking into account possible changes in air quality conditions. Therefore, a natural question arises whether it will be possible to ensure a comfortable and healthy living for occupants. There is a lack of methodologically robust intervention studies that support the improvement of energy efficiency measures by means of improved IAQ. It is also important to improve the knowledgebase in order to support the implementation of the related policies in Europe. In this context, overview of the results from before and after intervention measurements and emissions from building materials were presented, and the implications on IAQ were discussed. The results of the research provide data for the technical and administrative measures for the improvement of IAQ in residential buildings. / Žmonės įprastai praleidžia didžiąją dalį savo laiko patalpose - namuose ar kitų valstybinių ir privačių patalpų aplinkoje. Švaraus oro užtikrinimas gyvenamojoje aplinkoje yra labai svarbus visuomenės sveikatai. Oro teršalai patalpose yra glaudžiai susiję su pastato viduje vykstančiais procesais (emisijos iš pastato konstrukcijos, apdailos medžiagų, buitinių cheminių priemonių, ventiliacijos sistemos, maisto ruošos, gyventojų aktyvumo ir t.t.). Dėl nuolatinio vidaus oro maišymosi su išorės aplinkos oru, patalpų oro kokybė yra taip pat smarkiai įtakojama išorės oro kokybės. Pastatų renovacija daugiausia yra grindžiama ekonominiu aspektu. Atliekant ekonominius pastatų atnaujinimo veiksmus, paremtus didesniu energijos sąnaudų taupymu, neatsižvelgiama į galimus oro kokybės pokyčius. Todėl kyla natūralus klausimas ar po šių procesų pavyks užtikrinti patogią ir sveiką gyvenseną. Šiuo metu yra stygius metodologiškai stiprių mokslinių tyrimų, kurie nagrinėja energijos efektyvumo priemonių didinimo įtaką patalpų oro kokybei. Atsižvelgiant į tai, šiame darbe yra aptariami gauti rezultatai iš oro kokybės tyrimų daugiabučiuose pastatuose jų eksploatacijos metu bei aerozolio dalelių emisijos iš statybinių medžiagų pastato statybos ir atnaujinimo metu. Taip pat parengtos rekomendacijos daugiabučių pastatų atnaujinimui ir eksploatacijai, užtikrinant sveiką patalpų oro kokybę. Tyrimo rezultatai suteikia svarbios informacijos tiek techninėms, tiek ir administracinėms priemonėms, skirtoms... [toliau žr. visą tekstą]

<p>The uncertainty of the climate and health effects of aerosols is still large, one important reason being lack of knowledge of the primary emissions. This thesis combines laboratory and field experiments, and process modelling in an effort to better quantify the submicrometre aerosol emissions and to understand some of the processes in the atmosphere.</p><p>A parameterisation was derived for the source flux of sea salt particles (particles m^-2s^-1) in the size range 0.02-2.8 µm dry diameter (D_p), it is the first parameterisation to almost cover two full decades of the submicrometre sea salt aerosol production, and to include the effect of water temperature. This sea salt parameterisation was validated for temperate water in the 0.1-1.1 μm D_p range using in situ size resolved emissions of marine aerosol particles, which were measured with the eddy covariance (EC) method. For periods sampled air was heated to 300ºC in order to evaporate semi-volatile organics and isolate the sea salt fraction. Comparisons with the total aerosol emissions suggest that in these emissions organic carbon and sea salt are internally mixed in the same particles. Finally an aerosol dynamics model was modified for marine conditions. In the model parameterised emissions of sea salt was included together with aerosol dynamics, chemistry and clouds representative for the marine boundary layer. The sea salt emissions are together with secondary sulphate, and cloud processing able to reproduce a typical marine aerosol size distribution and cloud condensation nuclei population.</p><p>Measurements with the EC method of the road traffic related aerosol source number flux for D_p>0.011 µm show that the major part of the aerosol fluxes is due to road traffic emissions. Both an emission factor for the whole fleet mix in Stockholm (1.4x10¹⁴ vehicle^-1 km^-1) and separate emission factors for light- and heavy-duty vehicles (HDV) were deduced. The result shows that during weekdays 70-80% of the emissions come from HDV.</p>

The uncertainty of the climate and health effects of aerosols is still large, one important reason being lack of knowledge of the primary emissions. This thesis combines laboratory and field experiments, and process modelling in an effort to better quantify the submicrometre aerosol emissions and to understand some of the processes in the atmosphere. A parameterisation was derived for the source flux of sea salt particles (particles m-2 s-1) in the size range 0.02-2.8 µm dry diameter (Dp), it is the first parameterisation to almost cover two full decades of the submicrometre sea salt aerosol production, and to include the effect of water temperature. This sea salt parameterisation was validated for temperate water in the 0.1-1.1 μm Dp range using in situ size resolved emissions of marine aerosol particles, which were measured with the eddy covariance (EC) method. For periods sampled air was heated to 300ºC in order to evaporate semi-volatile organics and isolate the sea salt fraction. Comparisons with the total aerosol emissions suggest that in these emissions organic carbon and sea salt are internally mixed in the same particles. Finally an aerosol dynamics model was modified for marine conditions. In the model parameterised emissions of sea salt was included together with aerosol dynamics, chemistry and clouds representative for the marine boundary layer. The sea salt emissions are together with secondary sulphate, and cloud processing able to reproduce a typical marine aerosol size distribution and cloud condensation nuclei population. Measurements with the EC method of the road traffic related aerosol source number flux for Dp&gt;0.011 µm show that the major part of the aerosol fluxes is due to road traffic emissions. Both an emission factor for the whole fleet mix in Stockholm (1.4x1014 vehicle-1 km-1) and separate emission factors for light- and heavy-duty vehicles (HDV) were deduced. The result shows that during weekdays 70-80% of the emissions come from HDV.