Update to NRFA Trends pages

The graphs displayed on the trends pages of the NRFA website for the stations in the UK Benchmark Network have been updated.

The analysis of trends in river flow is important as increased flooding and water scarcity are among the UK’s most important climate change risks. Using the NRFA’s Benchmark Network of ‘near natural’ catchments (Harrigan et al 2018) allows for the detection of trends without the effects of human disturbance on river flow regimes.

Trends are analysed on the NRFA’s gauged daily flow time series and have been updated to the end of calendar year 2017 where available (previously shown to 2014). The graph for each station (e.g. 2002 - Brora at Bruachrobie) shows results of the Mann-Kendall (MK) test and statistic – a positive (negative) value indicates an increasing (decreasing) trend. Change points are determined using the Pettitt test and shown by a vertical line. More information on the trend analysis methodology is available in Harrigan et al. (2018).

Sites with trends pages can be selected from the NRFA's search page by choosing 'Filter' and Category -> Benchmark = 'Yes'.

The NRFA thank Elena Downes, Lancaster University MSci Placement student, for undertaking the work to update these plots.