1. Measurement and modelling of reactive trace gas fluxes from the Amazonian rainforest (CLAIRE-UK) Amy Valach Supervised by Prof. Nick Hewitt et al. Lancaster Environment Centre (?) urban (ClearfLo), rural (ECLAIRE) and background sites

2. Background Volatile organic compounds (VOCs) from biogenic and anthropogenic sources (fig. 2) affect atmospheric chemistry (PAN, O 3, SOA formation). >50% biogenic VOC emitted from tropical forests (fig. 3). Major component is isoprene with total global emissions of 600 Tg per annum (Guenther et al. 2006). Isoprene emissions are under circadian control, but also depend on light (PAR) and temperature. Lack of data on isoprene emissions in the tropics from direct quantification studies. Biogenic VOCs Anthropogenic VOCs Fig. 2 (left) The contribution of biogenic and anthropogenic organic carbon emissions in Tg/ a vs. latitude. Fig. 3 (right) The distribution of isoprene emissions in g/m a. 2

3. CLAIRE-UK Aims Quantify bVOC in the Amazon (pristine forest site for background values). Proton transfer reaction - mass spectrometer (PTR-MS) measures VOC concentrations. Use with sonic anemometer to measure fluxes by eddy covariance method. Investigate temporal cycles (seasonal and diurnal) of isoprene emissions.

4. Additional work Anthropogenic VOCs in urban and rural environments affect air quality. Seasonal variability (Jan/Feb and July/Aug) of VOC fluxes in London (ClearfLo): – Urban background site (North Kensington) – Kerbside site (Marylebone Road) – Central city site (KCL Strand flux tower) VOC fluxes in the Po Valley, Italy (ECLAIRE): – High pollution area in Europe – Effects on atmospheric chemistry during summer (Jun/July)

5. ClearfLo I preliminary results ClearfLo I Jan/Feb & ClearfLo II Jul/Aug/Sep Measured a range of biogenic and anthropogenic VOC species (concentrations and fluxes) Compare data with different temporal resolutions (5min – 1h) NK -> <- MRd

6. ECLAIRE (Italy) Rural/agricultural area Very high air pollution 40m flux tower in Bosco Fontana nature reserve Flux measurements and within- canopy gradient concentrations June-July flux:

7. Thanks!