The influence of variable weather patterns on river water quantity and quality regimes

✍ Scribed by R. L. Wilby

• Publisher: John Wiley and Sons
• Year: 1993
• Tongue: English
• Weight: 793 KB
• Volume: 13
• Category: Article
• ISSN: 0899-8418
• DOI: 10.1002/joc.3370130408

✦ Synopsis

Abstract

There is growing awareness as to the potential sensitivity of hydrological systems to climate change. In particular long‐term changes in precipitation variability will have consequences for runoff regimes and thence solute transport. By utilizing the Lamb's Weather Type register in conjunction with observed 24 h rainfall totals it was possible to determine daily precipitation event probabilities and magnitudes for eight dominant synoptic classes. The stochastic rainfall series thus generated were then used to drive a robust hydrochemical model of an experimental catchment in the East Midlands, UK. The model results indicate that the frequencies of flood and drought are dependent upon the synoptic scenario, and especially the historical prevalence of both the anticyclonic and cyclonic patterns. Given that there have been marked fluctuations in the annual frequencies of these classes since the mid‐nineteenth century, long‐term variations in the severity and incidence of extreme flows may be anticipated. Clearly this will have major implications for the episodic export and dilution of solutes, sediments and microorganisms originating from both pristine and polluted hydrosystems.