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This study analyzes the relationship between drought processes and crop yields in Moldova, together with the effects of possible future climate change on crops. The severity of drought is analyzed over time in Moldova using the Standard Precipitation Index, the Standardized Precipitation Evapotranspiration Index, and their relationship with crop yields. In addition, rainfall variability and its relationship with crop yields are examined using spectral analysis and squared wavelet coherence. Observed station data (1950–2020 and 1850–2020), ERA5 reanalysis data (1950–2020), and climate model simulations (period 1970–2100) are used. Crop yield data (maize, sunflower, grape), data from experimental plots (wheat), and the Enhanced Vegetation Index from Moderate Resolution Imaging Spectroradiometer satellites were also used. Results show that although the severity of meteorological droughts has decreased in the last 170 years, the impact of precipitation deficits on different crop yields has increased, concurrent with a sharp increase in temperature, which negatively affected crop yields. Annual crops are now more vulnerable to natural rainfall variability and, in years characterized by rainfall deficits, the possibility of reductions in crop yield increases due to sharp increases in temperature. Projections reveal a pessimistic outlook in the absence of adaptation, highlighting the urgency of developing new agricultural management strategies. [ABSTRACT FROM AUTHOR]

Better understanding how fires respond to climate variability is an issue of current interest in light of ongoing climate change. However, evaluating the global‐scale temporal variability of fires in response to climate presents a challenge due to the intricate processes at play and the limitation of fire data. Here, we investigate the links between year‐to‐year variability of burned area (BA) and climate using BA data, the Fire Weather Index (FWI), and the Standardized Precipitation Evapotranspiration Index (SPEI) from 2001 to 2021 at ecoregion scales. Our results reveal complex spatial patterns in the dependence of BA variability on antecedent and concurrent weather conditions, highlighting where BA is mostly influenced by either FWI or SPEI and where the combined effect of both indicators must be considered. Our findings indicate that same‐season weather conditions have a more pronounced relationship with BA across various ecoregions, particularly in climatologically wetter areas. Additionally, we note that BA is also significantly associated with periods of antecedent wetness and coolness, with this association being especially evident in more arid ecoregions. About 60% of the interannual variations in BA can be explained by climatic variability in a large fraction (∼77%) of the world's burnable regions. Plain Language Summary: In the context of changing climatic conditions, it is increasingly important to better understand the relationship between climate and fires. This study proposes a method that evaluates climatic conditions, either antecedent to or coincident with the fire season or the composite effect of both. It shows that the interannual variability of the global burned area for the period 2001 to 2021 is explained by climatic factors by around 60%. Our results also indicate that climatic drivers concurrent to the fire season prevail moderately over the antecedents. This suggests that the expected increase in burned area due to warmer and/or drier conditions can be mitigated where these climate conditions limit fuel availability. Key Points: 2/3 of the interannual variations in area burned are explained by climate in a substantial portion of the world's burnable regionsSame‐fire‐season weather is moderately more important than antecedent‐fire‐season weather for burned area variabilityBurned area is associated with antecedent wet and cool periods especially in the more arid areas [ABSTRACT FROM AUTHOR]

This study provides a global analysis of the relationship between drought metrics obtained from several climatic, hydrologic and ecological variables in a climate change framework using CMIP6 model data. A comprehensive analysis of the evolution of drought severity on a global scale is carried out for the historical experiment (1850–2014) and for future simulations under a high emissions scenario (SSP5‐8.5). This study focuses on comparing trends in the magnitude and duration of drought events according to different standardized indices over the world land‐surface area. The spatial and temporal relationship between the different drought indices on a global scale was also evaluated. Overall, there is a fairly large consensus among models and drought metrics in pointing to drought increase in southern North America, Central America, the Amazon region, the Mediterranean, southern Africa and southern Australia. Our results show important spatial differences in drought projections, which are highly dependent on the drought metric employed. While a strong relationship between climatic indices was evident, climatic and ecological drought metrics showed less dependency over both space and time. Importantly, our study demonstrates uncertainties in future projections of drought trends and their interannual variability related to the relationship among indices, stressing the importance of coherent climatic, hydrological and plant physiological patterns when analyzing CMIP6 model simulations of droughts under a warming climate scenario. Plain Language Summary: Using climate change models, we perform a drought analysis in terms of climatic, hydrologic and ecological variables on a global scale, studying the projections under a high emission scenario. We analyze how drought events will evolve in the future with respect to their magnitude and duration, and if the different drought metrics agree in space and time. In general, models and metrics agree that there will be drought increase in southern North America, Central America, the Amazon region, the Mediterranean, southern Africa and southern Australia. However, results differ across the world and really depend on the metric used. We show that climatic indices are strongly connected with each other, but no so related to ecological ones. We also find that there are uncertainties in future projections of drought trends, highlighting that we should always take into account the spatial and temporal agreement between climatic, hydrological and plant physiological patterns when studying drought projections. Key Points: Important differences in drought projections as a function of drought metricsThe temporal relationship between the precipitation‐based climatic metrics is high worldwideA weak relationship is found between climatic and ecological drought indices [ABSTRACT FROM AUTHOR]

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Drought monitoring systems are real‐time information systems focused on drought severity data. They are useful for determining the drought onset and development and defining the spatial extent of drought at any time. Effective drought monitoring requires databases with high spatial and temporal resolution and large spatial and temporal coverage. Recent reanalysis datasets meet these requirements and offer an excellent alternative to observational data. In addition, reanalysis data allow better quantification of some variables that affect drought severity and are more seldom observed. This study presents a global drought dataset and a monitoring system based on the Standardized Precipitation Evapotranspiration Index (SPEI) and ERA5 reanalysis data. Computation of the atmospheric evaporative demand for the SPEI follows the FAO‐56 Penman‐Monteith equation. The system is updated weekly, providing near real‐time information at a 0.5° spatial resolution and global coverage. It also contains a historical dataset with the values of the SPEI at different time scales since January 1979. The drought monitoring system includes the assessment of drought severity for dominant crop‐growing areas. A comparison between SPEI computed from the ERA5 and CRU datasets shows generally good spatial and temporal agreement, albeit with some important differences originating mainly from the different spatial patterns of SPEI anomalies, as well as from employing long‐term climate trends for different regions worldwide. The results show that the ERA5 dataset offers robust results and supports its use for drought monitoring. The new system and dataset are publicly available at the link https://global‐drought‐crops.csic.es/. [ABSTRACT FROM AUTHOR]