Atmospheric pollution and climate change present major threats to biodiversity, both globally and within the UK. National and regional governments have commitments to address these issues. Responding to the threats posed by air pollution and climate change requires an understanding of the nature and extent of their impacts. Monitoring allows changes in biodiversity to be detected and quantified and therefore provides objective evidence on which to develop scientific understanding, policy and management responses. A wide range of monitoring programmes cover different aspects of UK biodiversity. Changes in the populations of some animal groups,.