Evaluation of ERA5 and ERA5-Land reanalysis precipitation datasets over Spain (1951–2020)

Atmospheric Research, Journal Year: 2023, Volume and Issue: 284, P. 106606 - 106606

Published: Jan. 4, 2023

Reanalysis precipitation estimates are widely used in the fields of meteorology and hydrology because they can provide physical, spatial, temporal coherent long time series at a global scale. Nevertheless, as pre-requisite for many applications their performance needs to be assessed. The objective this study was evaluate European Centre Medium-Range Weather Forecasts (ECMWF) latest fifth-generation reanalysis products, i.e., ERA5 ERA5-Land, country scale Spain. For doing so, we compared it against high-resolution product Spanish Meteorological Agency which spans approximately 70 years (1951–2020). A comprehensive assessment (continuous, categorical, probability distribution function (pdf), spatial pattern, trend) performed order ascertain quality products. Results analysis revealed general agreement between observations ERA5-Land/ERA5 estimates: spearman correlation values 0.5 0.9, Root Mean Square Error (RMSE) mostly 2 8 mm/d Kling Gupta Efficiency (KGE) >0.4. Categorical additionally indicated good (Heiken Skill score (HSS) score, also known kappa, 0.4 0.8). found dependent on climatic region, intensity orography. Correlation north-west (higher values) south-east (lower gradient while relative bias (RBIAS) RMSE patterns were positively correlated with slope (ρ = 0.41/0.35, 0.69/0.70, respectively). In addition, by categorical analysis, along Mediterranean coast wet (i.e., overestimation days precipitation) found. detection capacity (kappa) shown negative −0.29/−0.34). Worst model is obtained during summer months, generalized overestimation. pdf that tended overestimate light (≥1 < 5 mm/day), moderate (≥5 20 mm/day) categories underestimating heavy (≥20 40 violent (≥40 categories. Moderate provided best capacity, precipitation-intensity analysis. showed reproduce trends observations. ERA5-Land ERA5, different resolution, very similar all considered. northern highlighted most critical modelling purposes its performance.

Language: Английский

---

Drought Severity and Trends in a Mediterranean Oak Forest

Hydrology, Journal Year: 2023, Volume and Issue: 10(8), P. 167 - 167

Published: Aug. 10, 2023

Drought is a significant natural hazard with widespread socioeconomic and environmental impacts. This study investigated the long-term drought characteristics in Mediterranean oak forest ecosystem using Standardized Precipitation Evapotranspiration Index (SPEI) at various time scales seasons. The analysis was based on series dataset obtained from meteorological station located University Forest of Taxiarchis Greece. encompassed substantial span 47 years continuous monitoring, 1974 to 2020. To accomplish goals current research, SPEI calculated for 3, 6, 12, 24-month periods, events were identified. Mann-Kendall (M-K) test used analyze trends severity evaluate significance. results showed that shorter (SPEI3 SPEI6) more efficient identifying short-term droughts, while longer (SPEI12 SPEI24) better less frequent but longer-lasting episodes. consistently revealed positive across all seasons scales, indicating an overall transition towards wetter conditions. Nearly data SPEI12 SPEI24 exhibited statistically upward (wetter conditions) 95% confidence level. However, intense detected during recent decade seasonal analysis. Additionally, as scale expanded, magnitude these increased. findings contributed understanding dynamics forests provided valuable information management climate change adaptation planning.

Language: Английский

---

Long-term trends in atmospheric rivers over East Asia

Climate Dynamics, Journal Year: 2022, Volume and Issue: 60(3-4), P. 643 - 666

Published: June 3, 2022

Language: Английский

---

Analysis of Hydrometeorological Trends and Drought Severity in Water-Demanding Mediterranean Islands under Climate Change Conditions

Climate, Journal Year: 2023, Volume and Issue: 11(5), P. 106 - 106

Published: May 15, 2023

Global climate change has emerged as a problem in recent years, and its effects will likely continue to increase the future. Several scientific studies conducted Mediterranean region have demonstrated relatively stationary trends for annual precipitation significant upward mean temperature. These present several implications, especially Greek islands that serve major summer tourist destinations where population is already unable meet their water demands. The aim of this study investigate both long- short-term variations temperature on three Sea (Mykonos, Naxos, Kos). rainfall trends, well magnitudes at yearly, seasonal, monthly time steps, were determined using non-parametric Mann–Kendall trend test. Standardized Precipitation Index (SPI) was employed identify drought periods. According results, slightly increased (almost stationary) islands, although rise not statistically significant. All experienced sharp air temperatures. may experience episodes result high increase, which would drastically reduce amount water, available use due evapotranspiration. For region, necessity management strategy stop or diminish severity grown into matter great concern. It crucial take measures conduct relevant research order create conditions adaptation mitigation consequences appearance phenomena.

Language: Английский

---

Evaluation of Rainfall Erosivity in the Western Balkans by Mapping and Clustering ERA5 Reanalysis Data

Atmosphere, Journal Year: 2023, Volume and Issue: 14(1), P. 104 - 104

Published: Jan. 3, 2023

The Western Balkans (WB) region is highly prone to water erosion processes, and therefore, the estimation of rainfall erosivity (R-factor) essential for understanding complex relationships between hydro-meteorological factors soil processes. main objectives this study are (1) estimate spatial-temporal distribution R-factor across WB by applying RUSLE RUSLE2 methodology with data period 1991 2020 (2) apply cluster analysis identify places high risk, thereby offer a means targeting suitable mitigation measures. To assess variability, ERA5 reanalysis hourly (0.25° × 0.25° spatial resolution) comprised 390 grid points were used. calculations made on decadal resolution (i.e., 1990s, 2000s, 2010s), as well whole (1991–2020). In order reveal patterns erosivity, k-means clustering algorithm was applied. Visualization mapping performed in python using Matplotlib, Seaborn, Cartopy libraries. Hourly precipitation intensity monthly totals exhibited pronounced variability over area. High values observed SW >0.3 mm h−1 average, while least seen Pannonian Basin far south (Albanian coast), where mean less than an average 0.1 h−1. very both methods. calculated 790 MJ ha−1·h−1·yr−1, which 58% higher obtained from (330 ha−1·h−1·yr−1). at timescales suggested rise 14% 2010s. methods implies better case five clusters (K = 5) regarding values. maps presented research can be useful tools assessment control works, especially agriculture land use planning. Since important part models (RUSLE RUSLE2), results used guide landscape modeling, measures regional scale.

Language: Английский

---

Analyzing and Modeling the Spatial-Temporal Changes and the Impact of GLOTI Index on Precipitation in the Marmara Region of Türkiye

Atmosphere, Journal Year: 2023, Volume and Issue: 14(3), P. 489 - 489

Published: March 1, 2023

Precipitation is a particularly important part of the Earth’s hydrological cycle and, therefore, necessary variable for maintaining natural balance. This study investigated past, present, and future changes in precipitation Marmara region, examined effects global warming on this variable. The period was from 1960 to 2020, climate data 15 synoptic stations region were used purpose. To achieve objectives study, linear 6th order polynomial regression, ombrothermic hythergraph diagrams, geostatistical models, Mann-Kendall test, Pearson correlation, standard Z-scores, multi-layer perceptron artificial neural network models (MLP-ANN) model predict precipitation. results regression analysis showed that stations, 6 had an increasing trend, trendless pattern, 3 decreasing trend. In terms periodic analysis, main downward trend started 1964 continued until 1992, while upward 1992 2016. lack over six seven months year, stronger than temperature changes. addition, highest observed southeast coast Black Sea, lowest eastern parts region. Moreover, except Bilecik Kocaeli long-term at other significant. Among only Sarıyer positive correlation with during annual period. developed ANN accurate simulating predicting next years.

Language: Английский

---

Exploring Recent (1991–2020) Trends of Essential Climate Variables in Greece

Atmosphere, Journal Year: 2024, Volume and Issue: 15(9), P. 1104 - 1104

Published: Sept. 11, 2024

Europe and the Mediterranean are considered climate change hot spots. This is reason why this paper focuses on analysis of trends essential variables in a country, Greece. The analyzed period 1991–2020, dataset used ERA5-Land (produced by European Center for Medium-Range Weather Forecasts), which has global coverage an improved resolution ~9 × 9 km compared to other datasets. Significant climatic changes across Greece have been put evidence during period. More specifically, country averaged 30-year trend temperature +1.5 °C, locally exceeding +2 increasing positively correlated with distance areas from coasts. Accordingly, number frost days decreased throughout country. In terms rainfall, major part experienced annual rainfall amounts, while 86% Greek area positive heavy (>20 mm). Finally, multiple signal consecutive dry was found (statistically non-significant Greece).

Language: Английский

---

Landslide Susceptibility Mapping under the Climate Change Impact in the Chania Regional Unit, West Crete, Greece

Land, Journal Year: 2023, Volume and Issue: 12(1), P. 154 - 154

Published: Jan. 3, 2023

Over the preceding decades, climate change has affected precipitation, most common factor triggering landslides. The aim of this study is to highlight impact by examining precipitation trends in Chania regional unit, Greece, with help time series provided 21 local meteorological stations covering a period from 1955 2020. analysis also focuses on extreme events February 2019, where monthly cumulated amount reached 1225 mm, one highest ever recorded Greece. Moreover, an inventory past and recent landslides was created intensity–duration landslide thresholds were evaluated. Daily simulations three state-of-the-art models used analyze patterns under two representative concentration pathways (RCPs), 4.5 8.5, for 2030–2060. application estimated daily future projections revealed increase following decades that can activate and, therefore, highlighted impact. mean annual 10 years evaluated along hydro-geological data inventory, providing approximately 5% more effective susceptibility map compared relative maps produced using control (1976–2005) 30 years. Thus, emerges as dynamic process needs be regularly updated due significant ongoing changes because change.

Language: Английский

---

Drought Assessment in Greece Using SPI and ERA5 Climate Reanalysis Data

Sustainability, Journal Year: 2023, Volume and Issue: 15(22), P. 15999 - 15999

Published: Nov. 16, 2023

The present work aims to assess the spatial variability and trends of annual rainfall meteorological drought in entire territory Greece utilising ERA5 reanalysis precipitation dataset European Centre for Medium-Range Weather Forecasts (ECMWF), which spans from January 1940 December 2022 (an 83-year period). Drought assessment took place based on Standardized Precipitation Index (SPI) timescales ranging 1 month 12 months. Evaluation was carried out by calculating SPI using observed data five stations. severity (SPI-1), 3 (SPI-3), 6 (SPI-6) (SPI-12) months were analysed Theil–Sen slope method Mann–Kendall trend test. results indicate significant, both increasing decreasing, at 95% significance level Aegean Islands, western Crete mainland Greece. also significant SPI-12 Islands Peloponnese. Trend analysis SPI-1, SPI-3 SPI-6 a mixture non-significantly wetting national scale. In conclusion, seems be valuable tool monitoring

Language: Английский

---

Increasing Trends in Discharge Maxima of a Mediterranean River during Early Autumn

Water, Journal Year: 2023, Volume and Issue: 15(6), P. 1022 - 1022

Published: March 8, 2023

Climate change has influenced the discharge regime of rivers during past decades. This study aims to reveal climate-induced interannual trends average annual and maxima in a Mediterranean river from 1981 2017. To this aim, Pinios basin was selected as area because it is one most productive agricultural areas Greece. Due lack sufficient measurements, simulated daily discharges for three upstream sub-basins were used. The trend analysis based on multi-faceted approach using Mann-Kendall tests, Quantile-Kendall plots, generalized additive models (GAMs) fitting non-linear trends. methodological proposed can be applied anywhere investigate climate effects. results indicated that decreased 1980s, reaching minimum early 1990s, then increased middle 1990s 2017, approximately levels 1980s. A more in-depth unraveled September characterized by statistically significant increasing two sub-basins. These are anthropogenically low affected, thus highlighting clear impact may have critical socioeconomic implications basin.

Language: Английский

---