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The present work aims to address the physical properties of different drought types under near-future climates in the Mediterranean. To do so, we use a multi-model mean of the bias-adjusted and downscaled product of five Earth System Models participating in the Coupled Model Intercomparison Project—phase6 (CMIP6), provided by Inter-Sectoral Impact Model Intercomparison Project (ISIMIP), under four shared socioeconomic pathways (SSP1–2.6, SSP2–4.5, SSP3–7.0, and SSP5–8.5) for the period 2021–2060, to estimate the Standardized Precipitation Evapotranspiration Index (SPEI) at 1-, 6-, and 12-month time scales, and address the meteorological, agricultural, and hydrological drought, respectively. Additionally, SPEI is calculated from the bias-adjusted CMIP6 historical simulations and the reanalysis 'WFDE5' for 1980–2014 as a historical and reference period. The comparison of the CMIP6 with WFDE5 reveals a consistently increasing tendency for drought occurrences in the Mediterranean, particularly for agricultural and hydrological drought time scales. Nonetheless, an overestimation in historical trend magnitude is shown by the CMIP6 with respect to WFDE5. The projection results depict drought frequencies ranging between 12 and 25% of the studied period 2021–2060, varying with regions and climate scenarios. The tendency to increase the drought frequency is more pronounced in the southern than northern Mediterranean countries. Drought severity is remarkable in the aggregated time scales; consequently, more pressure is foreseen in the food and water sectors. Drought seasonality reveals a higher tendency for drought occurrences in summer (autumn) months for the meteorological (agricultural) droughts. The driving factor(s) for drought occurrence strongly depends on regional climate characteristics. [ABSTRACT FROM AUTHOR]

Greater Cairo, Egypt, which lies in the apex of the Nile Delta, is one of the most populated regions in the world. Air pollution is a profound environmental issue prevailing in the urban/rural landscapes of this crowded megacity. The objectives of the present study were to utilize remotely sensed data in order to address the seasonal variations of the nocturnal surface urban heat island intensity (SUHII) as extracted from the American Moderate Resolution Imaging Spectroradiometer (MODIS) satellite and the related seasonal distribution of selected air pollutants, including nitrogen dioxide (NO2), sulphur dioxide (SO2), and carbon monoxide (CO) as extracted from the European TROPOspheric Monitoring Instrument (TROPOMI) for the period from 2018 to 2021. It is observed that there is clear nocturnal urban heat island over Greater Cairo, particularly at the administrative districts dominated by urban land use with high density of population and at the industrial and power generation locations. The highest SUHII is observed during winter. On the other hand, the selected pollutants also represent an urban pollution island (UPI) capping the regions of high SUHII. At the seasonal level, the highest NO2 correlation with the SUHII occurs during spring (R2 = 0.59), while the CO correlates maximum during winter (R2 = 0.51). Nonetheless, the seasonal SO2 distribution is poorly related to the SUHII as this specific pollutant is significantly associated with the industrial land use. Climatic and topographic factors could intensify the distribution of air pollution in the study area. Results of this study demonstrate the significance of geospatial technology tools in the subtle analysis and addressing regional air pollution. The outputs are also of a paramount implication on the management of urban environment and the adaptation of urban air quality. [ABSTRACT FROM AUTHOR]

Climate proxy data are required for improved understanding of climate variability and change in the pre-instrumental period. We present the first international initiative to compile and share information on pro pluvia rogation ceremonies, which is a well-studied proxy of agricultural drought. Currently, the database has more than 3500 dates of celebration of rogation ceremonies, providing information for 153 locations across 11 countries spanning the period from 1333 to 1949. This product provides data for better understanding of the pre-instrumental drought variability, validating natural proxies and model simulations, and multi-proxy rainfall reconstructions, amongst other climatic exercises. The database is freely available and can be easily accessed and visualized via http://inpro.unizar.es/. Measurement(s) pro pluvia rogation date • proxy climate indicator Technology Type(s) digital curation Sample Characteristic - Environment drought Sample Characteristic - Location Mexico • Guatemala • Ecuador • Peru • Chile • Argentina • Portugal • Kingdom of Spain • French Republic • Italy • The Philippines Machine-accessible metadata file describing the reported data: https://doi.org/10.6084/m9.figshare.14372093 [ABSTRACT FROM AUTHOR]

This study assesses the spatial and temporal characteristics (e.g., frequency, intensity, spatial extent) of meteorological drought in Syria. Specifically, drought was characterized using the observed rainfall data from 36 rain gauges spanning the period between 1990 and 2010 and covering the main climatic regions in Syria (i.e., Mediterranean, arid, semiarid and mountainous). Meteorological drought was assessed using the standardized precipitation index (SPI) at 12-month timescale, allowing for detecting the impacts of climate variability on agricultural droughts. The dominant modes of drought were defined using an S-mode of the principal component analysis. To assess the links between meteorological drought evolution and vegetation greening in Syria, the time series of SPI were correlated with the normalized difference vegetation index (NDVI). Time series of NDVI were retrieved from the remotely sensed National Oceanic and Atmospheric Administration Advanced Very High-Resolution Radiometer (NOAA/AVHRR) sensor at a spatial resolution of 25 km for the common period 1990–2010. Trend analysis suggests a statistically significant increase in the frequency and intensity of drought at 12-month timescale. The observed intensification of meteorological drought is mostly associated with the increase in mild and moderate droughts, relative to extremes and very extreme droughts. Results also suggest a statistically significant decrease (p < 0.05) in vegetation greening over Syria during the study period, especially in the eastern parts of the country. Our results demonstrate that the decrease in vegetation cover can directly be linked to the anomalous drought events, with Pearson' r coefficients generally above 0.6. This dependency was more highlighted during wintertime for the Mediterranean vegetation and in northeastern portions of the country. Overall, the increase in the frequency and intensity of meteorological drought, combined with a series of unrest and political instability, have drastic impacts on the agricultural sector in Syria, with serious implications for crop yield. [ABSTRACT FROM AUTHOR]

Monitoring and management of several environmental and socioeconomic sectors require climate data that can be summarized using a set of standard and meaningful climate metrics. This study describes a newly developed gridded dataset for the whole of Europe, which employed a set of 125 climate indices spanning different periods based on data availability, but mainly 1950–2017 and 1979–2017. This dataset comprehensively summarizes climate variability in Europe for a wide range of climate variables and conditions, including air temperature, precipitation, biometeorology, aridity, continentality, drought, amongst others. Climate indices were computed at different temporal scales (i.e. monthly, seasonal and annual) and mapped at a grid interval of 0.25°. We intend to update these indices on an annual basis. This dataset is freely available to research and end-user communities. Measurement(s) climate Technology Type(s) computational modeling technique Factor Type(s) air temperature • precipitation • sea level pressure • wind at 10 m • wind gust at 10 m • TOA radiation • radiation • insolation • snow density • snow depth • snowfall • total cloud cover • low cloud cover Sample Characteristic - Environment climate Sample Characteristic - Location Europe Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.12029427 [ABSTRACT FROM AUTHOR]