The importance of non-stationary multiannual periodicities in the North Atlantic Oscillation index for forecasting water resource drought

Rust, William, Bloomfield, John P., Cuthbert, Mark ORCID: https://orcid.org/0000-0001-6721-022X, Corstanje, Ron and Holman, Ian 2022. The importance of non-stationary multiannual periodicities in the North Atlantic Oscillation index for forecasting water resource drought. Hydrology and Earth System Sciences 26 (9) , 2449–2467. 10.5194/hess-26-2449-2022

Preview

PDF - Published Version Available under License Creative Commons Attribution. Download (3MB) | Preview

Abstract

Drought forecasting and early warning systems for water resource extremes are increasingly important tools in water resource management in Europe where increased population density and climate change are expected to place greater pressures on water supply. In this context, the North Atlantic Oscillation (NAO) is often used to indicate future water resource behaviours (including droughts) over Europe, given its dominant control on winter rainfall totals in the North Atlantic region. Recent hydroclimate research has focused on the role of multiannual periodicities in the NAO in driving low frequency behaviours in some water resources, suggesting that notable improvements to lead-times in forecasting may be possible by incorporating these multiannual relationships. However, the importance of multiannual NAO periodicities for driving water resource behaviour, and the feasibility of this relationship for indicating future droughts, has yet to be assessed in the context of known non-stationarities that are internal to the NAO and its influence on European meteorological processes. Here we quantify the time–frequency relationship between the NAO and a large dataset of water resources records to identify key non-stationarities that have dominated multiannual behaviour of water resource extremes over recent decades. The most dominant of these is a 7.5-year periodicity in water resource extremes since approximately 1970 but which has been diminishing since 2005. Furthermore, we show that the non-stationary relationship between the NAO and European rainfall is clearly expressed at multiannual periodicities in the water resource records assessed. These multiannual behaviours are found to have modulated historical water resource anomalies to an extent that is comparable to the projected effects of a worst-case climate change scenario. Furthermore, there is limited systematic understanding in existing atmospheric research for non-stationarities in these periodic behaviours which poses considerable implications to existing water resource forecasting and projection systems, as well as the use of these periodic behaviours as an indicator of future water resource drought.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Earth and Environmental Sciences
Additional Information:	This work is distributed under the Creative Commons Attribution 4.0 License.
Publisher:	Copernicus Publications
ISSN:	1607-7938
Date of First Compliant Deposit:	16 May 2022
Date of Acceptance:	12 April 2022
Last Modified:	18 May 2023 17:27
URI:	https://orca.cardiff.ac.uk/id/eprint/149769

Citation Data

Cited 1 time in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item