Fig. 1

OPAL operations span outreach to research goals and utilise OPAL national surveys to deliver citizen science elements of the public engagement in science programme. One survey was produced per research centre, except Biodiversity where three were produced. The number of papers (i.e. where OPAL is mentioned in acknowledgements) and number of sites monitored (i.e. unique latitude and longitude) are displayed for each science theme. Beneficiary figures were obtained from OPAL monthly evaluation forms between April 2010–December 2013 and media figures were based on circulation and web hits to online articles over the period which the survey was at its most popular. ‘Other outputs’ record citizen science tools and output beyond OPAL surveys [24–26]