Climate Control of Multidecadal Variability in River Discharge and Precipitation in Western Europe

Abstract

The influence of large-scale climate variability on winter river discharge and precipitation across western Europe is investigated. We analyze 60 years of monthly precipitation and river flow data from 18 major western-European rivers and its relationship with dominant teleconnection patterns and climate indices in this region. Results show that winter river flow is characterized by large interannual variability, best correlates with (a) the North Atlantic Oscillation (NAO) at the far-northern (R up to 0.56) and southern latitudes (R up to −0.72), and (b) the West Europe Pressure Anomaly (WEPA) at the middle and northern latitudes, from 42° N to 55° N (R up to 0.83). These indices also explain the interannual variability in autumn and spring discharge in rivers characterized by secondary floods. Compared to the other leading modes of atmospheric variability, WEPA increases the correlations with winter precipitation up to 0.8 in many regions of western and central Europe. A positive WEPA corresponds to a southward shift and an intensification of the Icelandic-Low/Azores-High dipole, driving enhanced precipitation and river discharge in these regions. The correlations with precipitation are slightly higher than those with river discharge, particularly in France, with clear latitudinal gradient. This trend suggests that water storage variability and other catchment characteristics may also influence the interannual variability of river discharge. Seasonal forecasting of the WEPA and NAO winter indices can become a powerful tool in anticipating hydrological risks in this region.

Role of Atmospheric Indices in Describing Shoreline Variability Along the Atlantic Coast of Europe

“…Winter values for climate indices (December–March) are generally used because they tend to have the strongest relation to wave climate and it is the climate hazards during winter (e.g., dune erosion, coastal flooding, overtopping) that are usually of most interest. So, here we demonstrate that shoreline response during winter is significantly correlated to winter WEPA, and, for example, Jalón‐Rojas and Castelle (2021) show that precipitation and river flows over the winter period across most of Europe are also positively correlated with winter WEPA. From a coastal management point of view, it is of interest to determine the longevity of the winter storm impacts; therefore, the annual shoreline response (December–March) was correlated with winter WEPA (December–March) for Perranporth and Truc Vert.…”

Effect of Teleconnection Patterns on the Formation of Potential Ecological Flow Variables in Lowland Rivers

“…Furthermore, Birsan [28] discovered strong negative correlations between the NAO (December-March) and the mean annual runoff in Romania, highlighting the role of large-scale atmospheric circulation and the orographic effects of the Carpathian Mountains. Jalón-Rojas and Castelle [59] investigated the influence of large-scale climate variability on winter river discharge in Western Europe. The strongest correlations were found with the NAO index, especially in the far northern regions (with correlation coefficients of up to 0.56) and in the southern latitudes (with only 0.72).…”

Utilization Management to Ensure Clean Water Sources in Coastal Areas

“…Determination of river discharge using climate data pertinent to the study site [38], Observation of river discharge is based on the variables of river width, water depth, flow velocity, and the results of hydrological analysis [39], as well as the river's flow velocity. The behavior observed in rivers The magnitude of the river's discharge is primarily determined by hydrological analysis [40], The selection of hydrological data must demonstrate a stable cycle capable of generating a concentrated river discharge [41], and The quantity of river discharge that occurs is influenced by the season, with the maximum river water discharge occurring in winter and the minimum occurring in summer [42].…”