Atmospheric Composition

The site measures a number of aerosols and reactive gases to understand atmospheric composition at this site. The site is a relatively clean site, which is classified as a ‘background’ monitoring site for the UK, which was recently confirmed by Malley et al. (2014) in studying O3 concentrations in Europe.

Figure 1: Dendrogram of 2007-10 EMEP sites derived by Ward's method of hierarchical clustering and reordered using non-negative matrix factorisation. The UK EMEP sites are identified with a red dot for those classified as Remote and a green dot for those classified as Polluted. The two UK EMEP sites of Harwell and Auchencorth are circled (Malley et al., 2014)

Measurements at the site include speciated inorganic water aerosol composition of both PM2.5 and PM10  at an hourly resolution, aerosol size-distribution by an SMPS, large range of C2-C7 organic precursor gases (VOCs) are measured at hourly time resolution by GC-MS, mercury measured hourly in its three principal forms (elemental gaseous, reactive gaseous and particle-bound) by a Tekran analyser.

 CEH is the lead organisation at this site, but also act as a local site operator for a number of national and international networks (Please refer to the list on the right).

Further details of several of the UK monitoring listed can be found here.


Malley, C. (2014) The application of hierarchical cluster analysis and non-negative matrix factorization to European atmospheric monitoring site classification. Atmospheric Research, 138, 30-40.