The observed increase in the frequency of droughts and heatwaves over the Northern Hemisphere in the 21st century poses immediate socio-economic threats affecting the well-being of the people by triggering negative health effects. These adverse hydro-meteorological conditions can lead to agricultural and ecological impacts such as crop losses, poor water quality conditions in water bodies, and wildfires. The reduction of the streamflow resulting from a drought event combined with high air temperatures also creates a threat to existing infrastructure. Several authors have reported cases of reduction of the cooling capacity in power plants, the reduction of tonnage in fluvial transportation, and the drop in reservoir storage leading to drinking water shortages (Naumann

The recent dry and warm years in Europe are often assessed as extreme in terms of socio-economic and environmental losses. However, the impact of a drought is a function of its duration. This fact needs to be considered in the evaluation of a drought. In this study, we use a hydrological model to analyze the 2018 European drought, an event that significantly affected vegetation. We show that the severity of the soil moisture drought is high in Central Europe and Mediterranean, but it does not reach the levels observed in the first half of the 20th century. Nevertheless, we demonstrate that when the multi-year 2014–2018 period is considered, its soil moisture drought severity is exceptional in a 253 year period, especially for Central Europe. While single-year droughts can be sustained by ecosystems like forests, the repeated stress exposure of such multi-year droughts may have significant impacts on their functioning. This is already evident in some regions of Central Europe, e.g. in the Czech Republic, Germany, and Poland.

We present a 250‐year (1766–2015) inventory of European meteorological, hydrological, and agricultural droughts derived from ensemble simulations of the mesoscale Hydrological Model (mHM). The inventory of droughts takes into account an ensemble of 100 simulations from the hydrological model, allowing for assessment of how different meteorological forcing and model parameterizations affect a drought ranking. For the most extreme droughts, the variability in the ranking of drought events is low, while for the years with moderate precipitation deficits, the variability increases. Despite the underlying uncertainties, our drought inventory shows increased recurrence of soil moisture droughts in the Mediterranean and declining spatial extent of hydrological drought in Central Europe over the last three decades.

<p>During the period 2018-2020, Europe experienced a series of hot and dry weather conditions with significant socioeconomic and environmental consequences. Yet, the extremity of these multi-year dry conditions is not recognized. Here, we provide a comprehensive spatio-temporal assessment of the drought hazard over Europe by benchmarking past exceptional events during the period from 1766-2020. We identified the 2018-20 drought event as a new benchmark having an unprecedented intensity that persisted for more than two years, exhibiting a mean areal coverage of 35.6% and an average duration of 12.2 months. What makes this event truly exceptional compared with past events is its near-surface air temperature anomaly reaching +2.8 K, which constitutes further evidence that the ongoing global warming is exacerbating present drought events. Our analysis shows that exceptional agricultural droughts enhanced by record-breaking near-surface air temperature anomalies have a significant impact (decline) on major crop yields (wheat, grain maize, and barley) across the European countries.  Furthermore, future events based on climate model simulations (CMIP5) suggest that Europe should be prepared for events of comparable intensity as the 2018-2020 event but with durations longer than any of those experienced in the last 250 years. Soil moisture drought projections synthesized in this study, even under a moderate emission scenario, indicate that decision-makers in Europe should be prepared for drought events of comparable intensity in future. Thus, the 2018--20 drought event could be considered as a wake-up call on agricultural policies. In this study, we compared and contrasted this event with earlier events of similar magnitudes and showed the role of increasing temperature rises. </p><p>DOI of dataset: https://zenodo.org/record/5801249</p><p>Reference: </p><p>Rakovec, O., Samaniego, L., Hari, V., Markonis, Y., Moravec, V., Thober, S., Hanel, M., Kumar, R. (2022). The 2018-20 multi-year drought sets a new benchmark in Europe. <em>Under Review, resubmitted version</em></p><p> </p>