A5024899017- Atmospheric chemistry and aerosols
- Atmospheric and Environmental Gas Dynamics
- Atmospheric Ozone and Climate
- Air Quality and Health Impacts
- Air Quality Monitoring and Forecasting
- Odor and Emission Control Technologies
- Soil and Water Nutrient Dynamics
- Peatlands and Wetlands Ecology
- Spectroscopy and Laser Applications
- Marine and coastal ecosystems
- Vehicle emissions and performance
- Atmospheric aerosols and clouds
- Climate Change and Health Impacts
- Advanced Chemical Sensor Technologies
- Remote Sensing in Agriculture
- Plant responses to elevated CO2
- Environmental Policies and Emissions
- Groundwater and Isotope Geochemistry
- Mercury impact and mitigation studies
- Land Use and Ecosystem Services
- Isotope Analysis in Ecology
- Hydrology and Watershed Management Studies
- Toxic Organic Pollutants Impact
- Surfactants and Colloidal Systems
- Climate Change and Sustainable Development
UK Centre for Ecology & Hydrology
2015-2024
Natural Environment Research Council
2014-2019
Crown Estate (United Kingdom)
2015
University of Cambridge
2004-2012
University of Edinburgh
2008
National Centre for Atmospheric Science
2004
University of Toronto
2003
University of Aberdeen
1996
Existing descriptions of bi-directional ammonia (NH3) land-atmosphere exchange incorporate temperature and moisture controls, are beginning to be used in regional chemical transport models. However, such models have typically applied simpler emission factors upscale the main NH3 terms. While this approach has successfully simulated spatial patterns on local global scales, it fails address environment- climate-dependence emissions. To handle these issues, we outline basis for a new modelling...
Adverse health effects from exposure to air pollution are a global challenge and of widespread concern. Recent high ambient concentration episodes pollutants in European cities highlighted the dynamic nature human gaps data knowledge about patterns. In order support impact assessment it is essential develop better understanding individual pathways people's everyday lives by taking account all environments which people spend time. Here we describe development, validation results an method...
Abstract. Eleven instruments for the measurement of ambient concentrations atmospheric ammonia gas (NH3), based on eight different methods were inter-compared above an intensively managed agricultural field in late summer 2008 Southern Scotland. To test over a wide range concentrations, was fertilised with urea midway through experiment, leading to increase average concentration from 10 100 ppbv. The deployed included three wet-chemistry systems, one offline analysis (annular rotating batch...
Measurements of the reactive uptake coefficient for N2O5 hydrolysis, γm, on sub-micron organic aerosols were performed in an entrained aerosol flow tube as a function relative humidity (RH), phase, partial pressure, and mean size. Aerosol phase determined simultaneously, chemical ionization mass spectrometry was used to detect decay rate presence malonic acid or azelaic aerosol. The γm solid be less than 0.001 (RH = 10–50%), acid, 0.0005 ± 0.0003. Aqueous yielded 0.0020 at 10% RH increased...
Abstract. Surface concentrations of secondary inorganic particle components over the UK have been analysed for 2001–2010 using EMEP4UK regional atmospheric chemistry transport model and evaluated against measurements. Gas/particle partitioning in simulations used a bulk approach, which may lead to uncertainties simulated aerosol. However, were able accurately represent both long-term decadal surface sulfate nitrate an episode early 2003 substantially elevated measured across by AGANet...
Abstract. Biogenic influences on the composition and characteristics of aerosol were investigated Bird Island (54°00' S, 38°03' W) in South Atlantic during November December 2010. This remote marine environment is characterised by large seabird seal colonies. The chemical submicron particles, measured an mass spectrometer (AMS), was 21% non-sea-salt sulfate, 2% nitrate, 8% ammonium, 22% organics 47% sea salt including sulfate. A new method to isolate spray signature from high-resolution AMS...
Abstract. The phase transitions and hygroscopic growth of two humic acid aerosols (Aldrich sodium salt Leonardite Standard (IHSS)) their mixtures with ammonium sulphate have been investigated using a combination techniques, Fourier transform infra-red (FTIR) spectroscopy tandem differential mobility analysis (TDMA). A factor 1.16 at 85% relative humidity (RH) was found for the Aldrich which can be regarded as an upper limit factors humic-like substances (HULIS) in atmospheric aerosol is...
A period of elevated surface concentrations airborne particulate matter (PM) in the UK spring 2014 was widely associated media with a Saharan dust plume. This might have led to over-emphasis on natural phenomenon and consequently missed opportunity inform public provide robust evidence for policy-makers about observed characteristics causes this pollution event. In work, EMEP4UK regional atmospheric chemistry transport model (ACTM) used conjunction speciated PM measurements investigate...
Abstract. A unique long-term dataset from the UK National Ammonia Monitoring Network (NAMN) is used here to assess spatial, seasonal and variability in atmospheric ammonia (NH3: 1998–2014) particulate ammonium (NH4+: 1999–2014) across UK. Extensive spatial heterogeneity NH3 concentrations observed, with lowest annual mean at remote sites (< 0.2 µg m−3) highest areas intensive agriculture (up 22 m−3), while NH4+ show less (e.g. range of 0.14 1.8 m−3 2005). Temporally, are influenced by...
Ammonia and ammonium have received less attention than other forms of air pollution, with limited progress in controlling emissions at UK, European global scales. By contrast, these compounds been significant past interest to science society, the recollection which can inform future strategies. Sal ammoniac (nūshādir, nao sha) is found extremely valuable long-distance trade (ca AD 600-1150) from Egypt China, where 6-8 kg N could purchase a human life, while pollution associated nūshādir...
Atmospheric aerosol has been shown to contain an organic component that includes a significant fraction of small dicarboxylic acids, particularly in the urban environment. As initial step toward understanding phase which particles may exist, detailed study into transitions malonic and oxalic acid aerosols carried out. Both (deliquescence efflorescence) bulk solution properties (equilibrium water vapor pressure solubility freezing curves aqueous solutions) are reported. An flow tube-FTIR...
Abstract. This is a study into the phase transitions of aerosol composed ternary system ammonium sulfate (AS) - malonic acid (MA) water using infrared extinction spectroscopy. Twelve compositions were studied in both deliquescence and efflorescence mode experiments. The presence MA fraction, by dry mass, (fMA) 0.1 an AS altered relative humidity at which occur atmospherically significant manner. For with 0.25
An evaluation has been made of a number contrasting atmospheric chemical transport models, varying complexity, applied to estimate sulphur and nitrogen deposition in the UK. The models were evaluated by comparison with annually averaged measurements gas, aerosol precipitation concentrations from national monitoring networks. relation performance criteria. They generally able satisfy criterion 'fitness for purpose' that at least 50% modelled should be within factor two measured values. second...
Abstract. A comprehensive European dataset on monthly atmospheric NH3, acid gases (HNO3, SO2, HCl), and aerosols (NH4+, NO3-, SO42-, Cl−, Na+, Ca2+, Mg2+) is presented analysed. Speciated measurements were made with a low-volume denuder filter pack method (DEnuder for Long-Term Atmospheric sampling, DELTA®) as part of the EU NitroEurope (NEU) integrated project. Altogether, there 64 sites in 20 countries (2006–2010), coordinated between seven laboratories. Bulk wet-deposition carried out at...
Abstract. Ammonia (NH3) in the atmosphere affects both environment and human health. It is therefore increasingly recognised by policy makers as an important air pollutant that needs to be mitigated, though it still remains unregulated many countries. In order understand effectiveness of abatement strategies, routine NH3 monitoring required. Current reference protocols, first developed 1990s, use daily samplers with offline analysis; however, there have been a number technologies since,...
We conduct the first 4D-Var inversion of NH3 accounting for bi-directional flux, using CrIS satellite observations over Europe in 2016. find posterior emissions peak more springtime than prior at continental to national scales, and annually they are generally smaller central Europe, but larger most rest Europe. Annual anthropogenic 25 European Union members (EU25) 25% higher very close (<2% difference) other inventories. Our annual EU25, UK, Netherlands, Switzerland 10%-20% when treating...
Anthropogenic activities emit ~2,000 Mg y −1 of the toxic pollutant mercury (Hg) into atmosphere, leading to long-range transport and deposition remote ecosystems. Global anthropogenic emission inventories report increases in Northern Hemispheric (NH) Hg emissions during last three decades, contradiction with observed decline atmospheric concentrations at NH measurement stations. Many factors can obscure link between concentrations, including trends reemissions previously released (“legacy”)...
NH3 is the major alkaline gas in atmosphere and third most abundant N-containing species, after N2 N2O. It an important target pollutant due to its role N deposition processes impacting over ecosystems, it also a precursor of fine particulate matter (PM), known cause several impacts on human health. Being able detect quantify essential for determining best mitigation policies reduce these impacts, yet this challenging given high spatial temporal variabilities pollutant.Miniaturized sensors...
Abstract. Leaf nitrogen and leaf surface area influence the exchange of gases between terrestrial ecosystems atmosphere, play a significant role in global cycles carbon, water. The purpose this study is to use field-based satellite remote-sensing-based methods assess pools five diverse European agricultural landscapes located Denmark, Scotland (United Kingdom), Poland, Netherlands Italy. REGFLEC (REGularized canopy reFLECtance) an advanced image-based inverse radiative transfer modelling...
Abstract. There is limited availability of long-term, high temporal resolution, chemically speciated aerosol measurements which can provide further insight into the health and environmental impacts particulate matter. The Monitor for AeRosols Gases (MARGA, Applikon B.V., NL) allows characterisation inorganic components PM10 PM2.5 (NH4+, NO3-, SO42-, Cl-, Na+, K+, Ca2+, Mg2+) reactive gases (NH3, SO2, HCl, HONO HNO3) at hourly resolution. following study presents 6.5 years (June 2006 to...