S. J. Lindley

The introduction of local air quality management in the United Kingdom : A review and theoretical framework

In the light of recent episodes of poor air quality in many of the U.K.s major urban areas, concern has been expressed regarding the apparent inability of existing air quality control procedures to effectively tackle contemporary scenarios. As a result of this, a new philosophy for air quality control has been sought which can provide a solid basis for the preservation and future improvement of air quality. It is proposed that a suitable mechanism for this would be found through the adoption of an integrated and holistic local air quality management approach. This paper will present and discuss a theoretical framework for the application of local air quality management in the U.K. and investigate the potential of the Environment Act (1995) to provide such a framework.

Uncertainties in the compilation of spatially resolved emission inventories — evidence from a comparative study

Abstract This paper examines the nature and extent of uncertainties associated with spatially resolved emission estimates with particular reference to an examination of alternative emissions data. Evidence is taken from recent research into the development of generic methodologies for the estimation of emissions of key urban pollutants from anthropogenic sources in the North West region of England. The inventory results, which are available in terms of a regional 5×5xa0km grid, a sub-regional 1×1xa0km grid and at the scale of the original activity data, are useful for a number of air quality management tasks. However, the requirements of producing a generic methodology which uses readily available data sources has been found to limit the degree of detail with which it is possible to develop estimation procedures and this has implications for the level of confidence associated with the results and their further application. One of the principal limitations is the availability of equivalent activity data for a number of administrative units. A further assessment of the results of the North West inventory has been made through a comparative study of the inventory data with other emissions data covering a sub-set of the study area. These investigations indicate that there are a number of variations between inventory results in terms of overall emission magnitudes and their spatial distribution. Observed differences between the estimates are attributable to different sources of activity data and emission factors and also as a result of the geographical data used to represent sources.

Procedures for the estimation of regional scale atmospheric emissions—An example from the North West Region of England

This paper considers the value of applying an alternative pro rata methodology to the estimation of atmospheric emissions from a given regional or local area. Such investigations into less time and resource intensive means of providing estimates in comparison to traditional methods are important due to the potential role of new methods in the development of air quality management plans. A pro rata approach is used here to estimate emissions of SO2, NOx, CO, CO2, VOCs and black smoke from all sources and Pb from transportation for the North West region of England. This method has the advantage of using readily available data as well as being an easily repeatable procedure which provides a good indication of emissions to be expected from a particular geographical region. This can then provide the impetus for further emission studies and ultimately a regional/local air quality management plan. Results suggest that between 1987 and 1991 trends in the emissions of the pollutants considered have been less favourable in the North West region than in the nation as a whole.

Estimation of spatially resolved road transport emissions for air quality management applications in the North West region of England

Spatially resolved estimates of combustion and non-combustion related emissions of CO, NOx, VOCs and PM from road transport sources have been made for the North West region of England in 1994. These have been generated using detailed emissions models for combustion related emissions of CO, NOx, VOCs and PM which take into account the different emissions profiles associated with particular vehicle groups, different road types and journeys under cold start conditions. Emissions estimates have been generated for a 1 x 1 km grid covering the regions urban and industrial zones and a 5 x 5 km grid for the whole study area. Emissions models have been generated and applied within a Geographical Information System (GIS) environment. Areas of uncertainty in the estimation procedure have been examined and the results compared with alternative data sources. Although the work centres upon the North West region of England, as far as possible the methods and data sources used are intended to be generic, particularly in respect to other administrative areas of the UK. In this way, this work can be considered to be of wider interest than at the local level alone.

Spatial and temporal variability in precipitation chemistry in the urban area of Greater Manchester

To investigate the spatial and temporal variability of acid deposition in the urban environment a small-scale intensive network of bulk collectors has been deployed around Greater Manchester, UK. This network has been in operation since 1986. The concentrations and deposition rates of non-marine (nm) sulphate, nitrate, ammonium, calcium and hydrogen are reported for 1994. Acidity was generally lower in the city centre of Manchester where calcium concentrations were highest. Calcium compounds in the urban atmosphere effectively buffer the precipitation acidity.

Emissions of acidifying air pollutants in the North West region of England

Most estimates of emission are concerned with the nation state level. This paper will discuss methods utilised in the estimates of emissions to the atmosphere of sulphur dioxide, volatile organic compounds and oxides of nitrogen from a densely populated and heavily industrialised region of the United Kingdom. Data on power generation, industrial plant, fuel usage, air, sea and road transportation, and human population statistics have been integrated into a method to provide regional emission estimates. The resulting emission patterns are described in terms of sources and emission density. Spatial and temporal patterns are identified and major sources of emissions discussed in terms of national control programmes. Transportation is the dominant source of oxides of nitrogen emissions whilst power generation is the dominant source of sulphur dioxide. The relative importance of the North West as an emission source within the UK is assessed. The change in the strengths of acidifying emissions between 1987 and 1992 is discussed and the rate of change in emission magnitudes between the North West region and the UK as a whole compared.