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We have analysed the impact of the North Atlantic jet on the winter PM 10 (particulate matter with aerodynamic diameter ≤ 10 μm) concentrations in Europe during a 10-year period. For this purpose we have extracted the daily latitude and strength of the jet from a reanalysis dataset and surface PM 10 observations from the AirBase network. We show that the detection of the jet over the eastern North Atlantic (0°–15° W) is preferred compared to the whole North Atlantic basin as this maximises the signal on the PM 10 concentrations. Four preferred jet positions have been identified over that region and season: southern (south of 41° N), central-southern (between 41° N and 51° N), central-northern (between 51° N and 63° N) and northern (north of 63° N). According to our results, the jet latitude exerts a stronger influence than the jet strength on the mean PM 10 levels. We also examine the impact of the jet positions on the full distribution of PM 10 as well as on the odds of PM 10 extremes (exceedances of the local winter 95th percentiles). The latter is done through a logistic regression model which considers the effect of the persistence of extremes and different time lags for the jet position. The northern position is associated with enhanced PM 10 concentrations (on average ∼9 μg m−3) over northwestern/central Europe and threefold increases in the odds of PM 10 extremes at most sites in the region. Similar increases have been found for PM 10 in southern Europe when the jet is in its central-northern position. In both cases, the rise in the PM 10 concentrations is associated with anticyclonic conditions over those regions and the impact on PM 10 extremes is maximised for time lags of around 1–2 days. On the other hand, the central-southern and southern jet positions yield large PM 10 decreases (on average around −9 μg m−3) in northwestern/central Europe and southern Europe, respectively. • First assessment of the impact of the jet on winter particulate matter (PM) in Europe. • PM concentrations more sensitive to the jet latitude than to the jet strength. • High PM concentrations and extremes in northern Europe for the northern jet position. • High PM in southern Europe when the jet is in the northern-central position. [ABSTRACT FROM AUTHOR]

• New set of weather regimes that improve the capability to reproduce wind power. • Monthly correlations of wind power with weather regime occurrence up to ~0.8. • High reproducibility of wind farms' capacity factors in Iberia and the United Kingdom. • Weather regimes explain day-to-day evolution of anomalous regional wind episodes. We have assessed the dependency of wind power resources in Western Europe on the atmospheric circulation as represented by a new set of 8 tailored weather regimes (WRs). For this purpose, we have derived wind capacity factors (CFs) from a meteorological reanalysis dataset and from high-resolution data simulated by the Weather Research and Forecasting (WRF) model. We first show that WRs capture effectively year-round onshore wind power production variability across Europe, especially over northwestern/central Europe and Iberia. Since the influence of the large-scale circulation on wind energy production is regionally dependent, we have then examined the high-resolution CF data interpolated to the location of more than 100 wind farms in two regions with different orography and climatological features, the United Kingdom and the Iberian Peninsula. The use of the monthly frequencies of occurrence of WRs as predictors in a multi-linear regression model allows explaining up to two thirds of the month-to-month CF variability for most seasons and sub-regions. These results outperform those previously reported based on Euro-Atlantic modes of atmospheric circulation, indicating that the use of WRs customized to the region of study is preferred to reproduce the evolution of wind energy resources. Finally, we have applied these WRs to understand the day-to-day evolution of specific episodes with anomalous regional wind power production. In particular, the wind energy deficit of summer 2018 in the United Kingdom and the surplus of March 2018 in Iberia stemmed from the combination of WRs associated with low and high CFs, respectively. These findings are relevant for the forecast of wind energy resources as the large-scale features of the atmospheric circulation captured by WRs can be modelled with considerably less uncertainty than wind speeds at wind farm sites. [ABSTRACT FROM AUTHOR]