We studied and reconstructed a severe Central Asian dust storm of November 4, 2021, through high-resolution TROPOMI UVAI spaceborne observations, ground-based aerosol measurements, and Lagrangian particle modeling. The dust storm was caused by the front part of a cold polar anticyclone front from the Ural-Volga regions, which struck the central and eastern parts of Uzbekistan under favorable atmospheric conditions. Two plumes spread out, causing a thick haze to blanket the region. The most severe dust storm effects hit the capital of Uzbekistan (Tashkent) and the Fergana Valley, where the thick atmospheric dust layer dropped the visibility to 200 m. PM₁₀ concentrations reached 18,000 µg/m³ (260-fold exceedance of the local long-term average). The PM_2.5 concentrations remained above 300 µg/m³ for nearly ten days, indicating an extremely long-lasting event. The dust storm was caused by an extremely strong summer heatwave of 2021 in Kazakhstan with unprecedentedly high temperatures reaching 46.5 °C. The long-lasting drought dried up the soil down to 50 cm depth, triggering the soil cover denudation due to drying out vegetation and losing its moisture. This event was the worst since 1871 and considering the increasing aridity of Central Asia, the onset of potentially recurring severe dust storms is alarming.

Future climate change and its impact on drought is critical for Uzbekistan, located in Central Asia, the world’s largest arid zone. This study examines the evolving intensity of climate change and drought events using multi-model ensembles (MMEs) derived from the Coupled Model Intercomparison Project Phase 5 and 6 (CMIP5 and CMIP6) simulated under the Representative Concentration Pathway and Shared Socioeconomic Pathway (RCP and SSP) scenarios. The projections show different rates of increase in temperature and precipitation under the RCPs and SSPs. Projected temperature increases are expected to reach up to 2–2.5 °C under SSP1-2.6, SSP2-4.5, and SSP3-7.0, by mid-century. By 2080–2099, an increase is projected of 2–3 °C in monthly mean temperatures throughout the year (SSP1-2.6), and a more pronounced increase in summer up to 3–4 °C (SSP2-4.5) and 4–6 °C (SSP3-7.0), with a marked contrast in conditions between the mountainous and desert regions of Uzbekistan. Regional changes in precipitation over the study periods show relatively little variability, except for FD, where notable trends are found. Under SSP1-2.6 and SSP2-4.5, the increase in precipitation is relatively modest, whereas the changes in SSP3-7.0 are more substantial, with some regions experiencing variations of up to 10–20 mm per period. The Standardized Precipitation Evapotranspiration Index (SPEI), calculated based on the projected temperature and precipitation, provides an estimate of future drought trends. Our results show increasing aridity under all scenarios by mid-century, with longer-term projections indicating stabilization around different SPEI values by 2100: RCP2.6 and SSP1-1.9 stabilize around −1.0; RCP4.5, RCP6.0, SSP2-4.5, and SSP3-7.0 stabilize around −1.5; while RCP8.5 and SSP5-8.5 scenarios project values of −2 or less by 2100. Notable differences in the SPEI index are found between lowland and foothill regions. In view of Uzbekistan’s heavy reliance on agriculture and irrigation, which are the sectors that are expected to be mostly affected by climate change, our study provides a scientific basis for informed policy decision-making. This includes various aspects such as planning and management water resources, as well as the broader socioeconomic development of the country.

Mountain glaciers are global hydroclimatic archives and accelerated glacier retreat threatens the irreversible loss of information about past hydroclimate. A hydroclimatic archive is defined as the integral of information about hydroclimatic conditions at the time of glacier mass accumulation reflected in the isotopic composition of ice stored in different layers. Using stable water isotope fingerprints in meltwater from 61 glaciers across five continents, we established the Global Glacier Meltwater Line and quantified the loss of climate information stored in glaciers. Results show high archive losses in European glaciers (47%), while Asian (31%) and North and South American (39%) glaciers have moderate losses. The only African glacier had the maximum archive loss (72%). Results suggest that these losses are locally influenced by changes in precipitation patterns and other hydroclimatic variations. Our study shows that the irreversible loss of hydroclimate archives preserved in the isotopic composition of glaciers can bias climate predictions and adaptation measures but can potentially act as a signal of glacier-related hazards.

This study provides a comprehensive spatiotemporal analysis of sand and dust storms (SDSs) in Uzbekistan using ground-based meteorological data from 2010 to 2023. The results reveal significant spatial heterogeneity in the SDS activity, with the highest frequency of SDS days observed in the southern and western regions, including Surkhandarya, Kashkadarya, Bukhara, Khorezm, and Republic of Karakalpakstan. In the most vulnerable areas, such as Karakalpakstan, Surkhandarya, and Kashkadarya, the annual number of SDS days can exceed 80 in certain years, reflecting a high recurrence of extreme dust events in certain climatic zones. About 53% of the SDS events were regional, affecting several stations, while 47% were localized, indicating a combination of large-scale dust transport and localized emissions. Seasonal patterns showed a peak SDS activity between March and August, coinciding with the dry season characterized by elevated temperatures, reduced soil moisture, and intense agricultural activity, all of which contribute to the surface exposure and increased vulnerability. This study found a significant variation in the event duration across regions, with Karakalpakstan and Surkhandarya experiencing the highest proportion of prolonged events due to its orography and persistent southerly wind patterns. Using ERA5 data and a decision tree regressor, the analysis identified the wind direction and mean wind speed as the most influential meteorological factors, followed by the maximum wind speed and soil temperature, with other variables such as solar radiation and soil moisture playing moderate roles. This study highlights the importance of regional wind patterns and geomorphology in SDS formation, with prevailing wind directions from the northwest, west, and south. The integration of the ERA5 reanalysis and machine learning techniques offers significant potential for improving SDS monitoring and studies.

The region: The study region encompasses parts of the mountain territory ofUzbekistan and the foothill region of Kazakhstan, including 12 meteorological stations in Central Asia.The study focus: The study focus was to compare reprocessed and re-gridded daily Special Sensor Microwave/Imager (SSM/I) snow depth data to observed snow depth data, evaluate different bias-correction methods, reconstruct missing daily snow depth observations, and conduct trend analysis of gap-filled snow depth from 1987 to 2023. Daily SSM/I snow depth values were extracted from the corresponding grid cells with a spatial resolution of 3.125 x 3.125 km, where twelve meteorological stations are located. Six bias-correction methods were used to “correct” original SSM/I snow depth data using in-situ observations. New hydrological insights for the region: The validation results collectively demonstrated strong agreement between corrected SSM/I estimates and observed station data across most locations, with the overall mean bias error declining -9.51 cm to -0.02 cm (percent bias: from -13.64 to 0.16). Notably, the trend analysis shows that most meteorological stations exhibited a significant reduction in the seasonal mean snow depth, where the rate of decline (0.74 cm snow depth per year) was more pronounced at higher elevations (>2000 m asl). By taking into account the shifts in the seasonal snow accumulation rates, decision makers and stakeholder institutions can adjust water distribution strategies in the region.