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Main workflow of the study. The figure outlines the main analysis steps undertaken in this paper. In addition to the mHM simulations driven by E-OBS data, we analyze and compare the results obtained against mHM simulation driven by ERA5 data and the GloFAS dataset.
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Floods regularly cause substantial damage worldwide. Changing flood characteristics, e.g., due to climate change, pose challenges to flood risk management. The spatial extent of floods is an important indicator of potential impacts, as consequences of widespread floods are particularly difficult to mitigate. The highly uneven station distribution i...
Citations
... While research has been conducted on spatially (Najibi et al 2023, Fang et al 2024, and multivariate typologies of compound floods (Wahl et al 2015, Bevacqua et al 2017, 2019, 2020, preconditioned and temporally compounding floods are less frequently studied, despite their significant implications for flood management. For example, temporallyclustered flood events are highly dangerous for hydraulic structures such as dams. ...
Floods are the most frequent natural hazard globally (2003–2023) and rank second in economic losses, according to EM-DAT, the International Disaster Database. When flood events occur in close succession, they pose significant challenges for emergency management due to limited recovery time between events. This study focuses on multi-peak (MP) floods, where peaks occur within hours to days. Using discharge data from 77 hydrometric stations in Northern Italy’s Po district, we examined statistical differences between MP and single-peak (SP) flood events and analyzed their seasonal patterns and generating mechanisms across diverse river regimes. We demonstrated that SP and MP events exhibit distinct statistical behaviors. The first type of events has more skewed distributions with heavy tails, while the second displays flatter distributions with lighter tails and higher mean values. Seasonal analyses suggest that MP floods in glacial and nival-pluvial regimes are influenced by glacier and snow melting, whereas those in the Padanian regime are driven by tributary routing effects. These triggering mechanisms seem to be responsible of the lighter tails of the distribution of MP floods. By highlighting the distinct statistical behaviors and generating mechanisms of MP and SP floods, we identified recommendations for designing MP flood hydrograph, supporting flood-risk management.
... to factors such as poor drainage systems, land-use changes, and unplanned urban growth (Bibi et al., 2023). However, it is important to note that flooding can also occur in developed countries, as evidenced by incidents in Europe (Fang et al., 2024). The lack of adequate infrastructure exacerbates the severity of floods, making them more impactful (Oloke et al., 2021;Wu et al., 2012). ...
Climate change, driven by human and natural processes, has increased flood frequency, impacting infrastructure, and resources. This study explores the relationship between land use/land cover (LULC) changes, rainfall patterns, and floods in Borno Metropolis, Nigeria, during the 2024 floods. Using Google Earth Engine (GEE), Landsat images from 1987 to 1990, 2013 to 2014, and 2024 were analyzed to calculate environmental indices, including the soil adjusted vegetation index (SAVI), normalized difference water index (NDWI), and normalized difference built-up index (NDBI). Sentinel-1 Synthetic Aperture Radar (SAR) images identified flood-affected areas in 2024. Rainfall data from CHIRPS (1987–2024) were analyzed using Mann–Kendall and Sen’s slope tests. Rule-based classification identified environmental changes, and statistical tests such as Pearson, Spearman, Kendall, and point–biserial were applied to assess relationships between climatic and environmental factors and floods. Python was used for all analyses. The findings revealed that 330 km² (12.6%) of the total area experienced flooding in 2024. Vegetation cover decreased by 16.1 km² (0.61%) in 2024 compared to 1987–1990, and non-vegetated areas increased significantly, reaching 19.5 km² in 2024. Built-up/bareland areas expanded by 59.4 km² (2.39%) from 2013–2014 to 2024. Spearman analysis effectively highlighted non-linear relationships between indices and floods. Point–biserial tests confirmed correlations between rainfall and flooding indicating that higher rainfall levels increase flood likelihood. The heavy rainfall of 863 mm in 2024 was a key factor in increasing runoff and intensifying floods. This study highlights critical flood-affected areas, providing valuable insights for flood management planning to help governments and local communities reduce risks.
... The nettle pots were flooded four times from January 2023 to February 2023, with one flooding event every six days over the span of 24 days, a flooding frequency observed in central Europe (Fang et al., 2024). Flooding events were simulated by irrigating each pot with 200 ± 2 g of water directly onto the loam topsoil with no contact between water and above-surface plant parts, including the aphids. ...
Surface waters are known to be polluted by a number of contaminants including synthetic pesticides. As flooding events intensify due to climate change, the flood-mediated transfer of pesticides to terrestrial ecosystems may also increase, potentially resulting in unforeseen exposure for terrestrial food-webs. To assess the uptake and trophic transfer of flood-mediated pesticide entries, we simulated riparian soil contamination caused by floodwater in a climate chamber pot experiment. The floodwater contained 31 fungicides and insecticides at environmentally relevant concentrations. We exposed potted stinging nettle plants (Urtica dioica) which were colonized by aphids to four sequential simulated flooding events and measured the pesticide concentrations in the soil, plant roots, plant stems and leaves, and aphids using HPLC-MS/MS. After four flooding events, the sum of insecticide and fungicide concentrations increased six-fold in soil and over thirty-fold in nettle plants compared to the concentrations after one flooding event. Bixafen and etofenprox showed the highest concentration in nettle
leaves and stems, indicating bioaccumulation. After the four flooding events, thirteen pesticides were detected at concentrations up to 13.7 μg kg−1 in the phytophagous aphids with picoxystrobin, fipronil, trifloxystrobin, spiroxamine, and fluopyram showing biomagnification. This study shows that commonly applied pesticides can be transferred to riparian soils by flooding events, taken up by plants and biomagnify in herbivorous insects.
... . In contrast, temperate regions like Northern Europe face increased flood risks due to more intense rainfall (Kundzewicz et al. 2014;Fang et al. 2024). ...
... These changes have far-reaching implications for water resource management, with altered runoff patterns, shifts in groundwater recharge, and increased evapotranspiration challenging water availability and distribution (Konapala et al. 2020). Regions that are becoming wetter, such as Northern Europe, are seeing increased runoff due to higher winter precipitation and earlier snowmelt (Barnett et al. 2005;Fang et al. 2024). However, in more arid regions like the Mediterranean and southern Africa, reductions in precipitation and increased evaporation are reducing streamflow and exacerbating water shortages (Milly et al. 2005;Tanarhte et al. 2024). ...
Climate change is fundamentally transforming global hydrological systems, exacerbating water scarcity, degrading water quality, and amplifying flood risks. This review critically examines the impacts of climate change on hydrological resilience, focusing on the increasing frequency and severity of extreme hydrological events such as floods and droughts, and their disproportionate effects on vulnerable regions with limited water resources. The review explores the role of nature-based solutions (NbS)—such as wetland restoration, reforestation, riparian buffer protection, and sustainable land management—as key strategies for mitigating climate-induced hydrological extremes. NbS leverage ecosystem services to reduce flood risks, improve water quality, and support groundwater recharge, offering adaptive, multi-functional approaches when combined with engineered infrastructure. In addition, the review discusses advancements in hydrological modeling, including the use of process-based models, machine learning algorithms, and scenario-based approaches, highlighting their potential for improving predictions of hydrological system responses to climate perturbations. Despite these advancements, significant gaps remain in understanding the interactions between cascading climate-induced extremes—particularly drought-to-flood transitions—and in addressing the challenges posed by limited data in transboundary water systems. This review underscores the importance of integrating ecological and infrastructural approaches in water resource management. It identifies emerging methodologies, such as real-time data assimilation and Bayesian frameworks, as crucial for enhancing the precision of hydrological predictions and informing effective decision-making. By synthesizing the latest research, this paper offers a comprehensive framework for addressing the challenges of climate-induced water crises and advancing hydrological resilience.
... This shows how the spatial extent of flood impact increases with climate change, even if the spatial extent of the precipitation event remains constant. There is, however, evidence that the spatial extent of extreme precipitation events increases (Fang et al., 2024;Matte et al., 2021). Consequently, increasing precipitation intensity due to climate warming can lead to critical discharge in regions that would not be severely affected by a specific event without climate warming. ...
In 2022, Europe faced an extensive summer drought with severe socioeconomic consequences. Quantifying the influence of human-induced climate change on such an extreme event can help prepare for future droughts. Here, by combining observations and climate model outputs with hydrological and land-surface simulations, we show that Central and Southern Europe experienced the highest observed total water storage deficit since satellite observations began in 2002, probably representing the highest and most widespread soil moisture deficit in the past six decades. While precipitation deficits primarily drove the soil moisture drought, human-induced global warming contributed to over 30% of the drought intensity and its spatial extent via enhanced evaporation. We identify that 14–41% of the climate change contribution was mediated by the warming-driven drying of the soil that occurred before the hydrological year of 2022, indicating the importance of considering lagged climate change effects to avoid underestimating associated risks. Human-induced climate change had qualitatively similar effects on the extremely low observed river discharges. These results highlight that global warming effects on droughts are already underway, widespread and long lasting, and that drought risk may escalate with further human-induced warming in the future.
In 2022, Europe faced an extensive summer drought with severe socio-economic consequences. By combining observations and climate model outputs with hydrological and land-surface simulations, we show that central and southern Europe experienced the highest observed total water storage deficit since satellite observations began in 2002, likely representing the highest and most widespread soil moisture deficit in the last six decades. While precipitation deficits primarily drove the soil moisture drought, human-induced global warming contributed to over 30% of the drought intensity and its spatial extent via enhancing evaporation. We identify that 14-41% of the climate change contribution was mediated by the warming that started to dry out the soil before the hydrological year 2022, indicating the importance of considering lagged effects of climate change to avoid underestimating associated risks. Qualitatively similar effects were observed in river discharges. These results highlight that global warming effects on droughts are already underway, widespread and long-lasting, and that drought risk may escalate with further human-induced warming in the future.
