Its raining again

Welcome back, hope you enjoyed the festive season. As the video on the previous post highlighted, there has been a recent increase in flooding (amongst other extreme events) in the UK. After having studied Robson's article 'Evidence for trends in UK flooding' I will decide whether or not it is likely that these events have been caused by climate change.


A scene from a small village in York after the flooding in February 2010- could the UK see more of this as the climate changes?

Robson’s 2002 study of trends in UK flooding emphasises how difficult it is to distinguish whether or not climate change is impacting on our weather conditions. Although some trends have indeed shown that winter rainfall and number of high flow days is increasing, this can not necessarily be attributed to climate change. Instead it can be attributed to natural climate variability, which can see short term changes in local weather conditions; but when trends are averaged over time, the average climate conditions have remained in a stable state. Unfortunately, although Robson did find evidence of increasing rainfall rates, the data series in the UK is not long enough (~60 years of appropriate coverage), nor reliable enough to rule out the cause being climate variability. Other factors such as changing land use can affect flooding records, especially when the changes involve urbanisation or agriculture as these can impact greatly on infiltration rates. This is why an urban environment is at greater risk of flooding.

So, although Robson did find evidence of increasing rainfall and number of high flow days in the UK, with the results from Scotland closely echoing the trends found in previous studies; climate change cannot be assigned as the cause, as other factors can’t be ruled out. In my opinion, however, with similar events happening around the globe; it is more likely that the main driver is the climate, whether it is just varying in the short term, or changing in the long term. For me, it is preferable to note this as the cause rather than change in landuse, although it is noted that this does play a role. Either way, due to this, the UK is experiencing more extreme weather events today than it has done in the past.