ATMOSPHERIC FIELD STUDIES GROUP

What's Occuring in Leeds (last updated Summer 2003):

FACT:- The average adult breathes 13,000 litres of air every single day.
As part of the Atmospheric Research Group based in the Department of Chemistry and School of the Environment, we have established this group to venture into the 'wilds' and study a variety of key tropospheric species. These data can then be used to make comparisons with computer model predictions which have been calculated by other members of the Atmospheric Chemistry group here in Leeds and other groups further afield We have used a variety of sites and have an ongoing itinerary of field campaigns which we are involved in.
The Group comprises of several projects: goto post macu voc fage bag

Some Atmospheric Pollutants.

Nitrogen Oxides (NOx)

Nitrogen oxides are released into the atmosphere mainly in the form of nitric oxide, (NO) as a result of fossil fuel combustion. Nitric oxide is readily oxidised to nitrogen dioxide (NO2) by reaction with ozone. Elevated levels of nitrogen oxides are generally observed in urban environments under stable meteorological conditions, when the airmass is unable to disperse. Together with hydrocarbons, they play an important role in the formation of ozone in the atmosphere, as described below. Nitrogen oxides have a lifetime of approximately 1 day with respect to conversion to nitric acid, which is removed from the atmosphere by direct deposition to the ground, or tranfer to aqueous droplets (eg. cloud or rainwater), thereby contributing to acid deposition.
Here for latest nitric oxide (NO) measurements in UK.
Here for latest nitrogen dioxide measurements in UK.

Ozone (O3)

The formation of ozone requires the presence of three ingredients: hydrocarbons, nitrogen oxides and sunlight. The sunlight provides the energy for the whole process to begin through near ultra-violet radiation which is able to dissociate certain stable molecules, leading to the formation of reactive species known as free radicals. In the presence of nitrogen oxides, these free radicals catalyse the oxidation of hydrocarbons to carbon dioxide and water vapour. Partially oxidised organic species such as aldehydes, ketones and carbon monoxide are intermediate oxidation products, and ozone is generated as a by-product. Since ozone itself is photodissociated to form free radicals, it promotes the oxidation chemistry, thereby catalysing its own formation (ie. it is an autocatalyst). Consequently, high levels of ozone are generally observed under sunny, summertime conditions in locations where the airmass has previously collected emissions of hydrocarbons and nitrogen oxides. Because of the time required for chemical processing, ozone formation tends to be downwind of pollution centres (ie. it is usual for the highest ozone levels to be in suburban or rural locations).
Here for latest ozone measurements in UK.

Carbon Monoxide (CO)

Carbon monoxide is both emitted into the atmosphere as a result of combustion processes, and is formed from the oxidation of hydrocarbons and other organic compounds. The highest concentrations are found close to combustion sources. It has an atmospheric lifetime of approximately one month with respect to further oxidation to form carbon dioxide.
Here for latest carbon monoxide measurements in UK.

AEA Technology have an archive of all the DETR sites this is available here

These a just a few of the minor trace gases present in the atmosphere. Here for a more detailed list of natural and man-made sources of a number of these trace gases.

The Hydroxyl Radical (OH)

Probably the most important of all radical species when considering tropospheric air chemistry. The dominant reaction is that with carbon monoxide (70-75%) and the majority of the remainder with methane . In the presence of oxygen at concentrations found in the troposphere, the hydrogen atom and methyl radical react rapidly to form hydroxy and methoxy radicals respectively. More.

Tropospheric Modeling.

One of the aims of these projects is for the information to be inputted into atmospheric models. Here in Leeds 1-dimensional box models are used. Here for more information.

Other Modeling Groups.

The Centre for Atmospheric Science at the University of Cambridge is involved with the modelling of data collected during both EASE 96 and EASE 97 campaigns at Macehead.

Field Campaign Itinerary (most recent first).

Atmospheric Chemistry Studies in the Oceanic Environment (ACSOE).

This is a NERC (Natural Environment Research Council) funded research project which has been proposed by the UK community of atmospheric chemists to provide experimental data on the main areas of tropospheric chemistry relevant to global climate change. More.

FIELD MEASUREMENTS.
OXICOA consortium (OXIdising Capacity of the Oceanic Atmosphere)- Mace Head 1996-7.

Participating institutions: UEA, Bristol, Birmingham, ITE, Imperial, Leeds, UMIST, Aberystwyth & Cambridge.

Species to be measured:

LEEDS:

OTHER GROUPS (in no particular order):

Aerosols Formation from Biogenic Organic Carbon (AEROBIC.)

This is a project funded by the European Commision to investigate in situ the formation of organic aerosols from the oxidation of natural hydrocarbons in forest areas of Mediterranean counties, by a detailed study of the aerosol composition, and of the gas phase in considerable products and in photochemical species. It will be able to elucidate the impact of organic aerosols on the local tropospheric chemistry and ozone budget.

Field Sites.

For more information on anything contained here (and much much more..), you might like to try a few of these sites.

Some Group Publications.

Acknowledgements:

We would like to thank the following organisations for their financial assistance:

For more information on anything discussed here you could always mail us

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This page was originally constructed a long time ago by Jim McQuaid-e-mail
Last modified on 02-11-02