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Hydrometeorological droughts are complex hazards expressed through the relative deviation in water availability relative to long‐term average conditions. The development and propagation of drought is governed by hydrological processes at different spatial scales including precipitation, evapotranspiration, overland flow, soil moisture, groundwater storage and discharge. Detailed investigation is thus required to evaluate associated linkages among various types of hydrometeorological drought to understand the likely impacts of climate change on drought characteristics (magnitude, frequency, duration and propagation). This study explores the impact of climate change on hydrometeorological drought for 10 Irish catchments, using standardized drought indices representing different components of the hydrological system. We employ 12 Global Climate Models from the Coupled Model Inter‐comparison Project phase 6 (CMIP6), forced with SSP370 and bias corrected to catchment conditions to force a conceptual hydrological model to generate hydrological projections for each catchment. The results indicate substantial drying during summer with associated increases in summer drought magnitude and frequency. However, simulations show a wide range of change, especially for hydrological drought (discharge and baseflow). Only modest changes in the magnitude and frequency of hydrological drought events were found, with increases in winter and spring precipitation offsetting summer dryness. Similarly, the probability of meteorological drought propagating to hydrological events (Standardized Streamflow Index/Standardized Baseflow Index), shows modest increases under the climate change projections considered. Findings highlight that drought, especially during summer are a critical climate change risk for adaptation. Plain Language Summary: Climate change aggravates the impact of hydrometeorological droughts on water availability and distribution in Ireland. Rainfall, evaporation, overland flow, soil moisture, groundwater storage, and the size and strength of discharges are the main factors that cause drought extent and duration. Therefore, for the sustainable development of ecosystems and water resources in a country, it is a requirement to evaluate associated linkages among various types of hydrometeorological drought to understand the likely impacts of climate change on drought characteristics (magnitude) and propagation. This paper explores the impact of climate change on hydrometeorological drought for 10 Irish catchments. The findings indicate significant summer drying, as well as increases in the magnitude and frequency of summer droughts. The probability of meteorological drought propagating to hydrological events, shows modest increases under the climate change projections considered. Drought, particularly during the summer, is a critical climate change risk for adaptation, according to the findings. Key Points: Changes in hydrometeorological drought characteristics under changing climate conditions were estimated; and the results indicate substantial drying during summer with associated increases in summer drought magnitude and frequencyIncreases in winter and spring precipitation result in a decrease in the frequency and magnitude of drought events outside summer and are critical for maintaining baseflow during summer. This also raises the risk of extreme droughts for a dry winter/springThe probability of drought propagation from meteorological to hydrological events increases for the 2050s but decreases for the end of century, highlighting the importance of increases in winter and spring precipitation to drought risk [ABSTRACT FROM AUTHOR]

The tropical Asian regions are particularly prone to catastrophic droughts due to high temperature and evaporation and their sensitivity to variable oceanic‐atmospheric circulation. The extent to which future global warming may intensify droughts in this populous region is a matter of utmost concern. Palaeoclimatic data can help inform scientists learn more about the temporal patterns and drivers of monsoon change over geological timescales. In this paper, we present a new 8,200 year biomarker record preserved in the annually laminated sediments of Maar Lake Twintaung, Myanmar. The δ13C27‐35 sedimentary record is mainly derived from leaf wax lipids in the lake catchment, which is presently dominated by C3 vegetation in the modern lake catchment. The δ13C27‐35 is mainly regulated by plant physiological and biochemical responses to drought stress and, as such, can be used as a proxy of past changes in moisture. The δ13C27–35 record reveals distinct decadal‐to‐centennial‐scale droughts superimposed on a trend of gradually decreasing summer monsoon intensity from the mid‐Holocene to late Holocene. Within the limits of the dating uncertainties, these decadal‐to‐centennial‐scale droughts are found to be well correlated with the southward shift of the Intertropical Convergence Zone. It highlights thepimportance of the Intertropical Convergence Zone shift (tropical monsoon trough) in regulating monsoon rainfall in the region. In addition, most of the droughts are likely to be linked with active volcanism and solar minima and suggest a coupled process between external drivers and internal climate dynamics. Key Points: Leaf wax n‐alkanes record in varved sediment of Maar lake Twintaung, MyanmarThe result indicates distinct decadal‐to‐centennial‐scale droughts over the past 8.2 kaThe drought cycles link with the ITCZ shift, solar and volcanic eruption [ABSTRACT FROM AUTHOR]

The Tarim River, the largest inland river in China, sits in the Tarim River Basin (TRB), which is an arid area with the ecosystem primarily sustained by water from melting snow and glaciers in the headstream area. To evaluate the pressures of natural disasters in this climate‐change‐sensitive basin, this study projected flash droughts in the headstream area of the TRB. We used the variable infiltration capacity (VIC) model to describe the hydrological processes of the study area, Markov chain Monte Carlo to quantify the parameter uncertainty of the VIC model. Ten downscaled general circulation models from the Coupled Model Intercomparison Project Phase 6 (CMIP6) were used to drive the VIC model, and the standardized evaporative stress ratio was applied to identify flash droughts. The results demonstrated that the VIC model after Bayesian parameters uncertainty analysis can efficiently describe the hydrological processes of the study area. In the future (2021–2100), compared with the plain region, the alpine region has higher flash drought frequency and intensity. Compared with the historical period (1961–2014), the frequency, duration, and intensity of flash droughts tend to increase throughout the study area, especially for the alpine area. Moreover, based on variance decomposition, CMIP6 model is the most important uncertainty source for flash drought projection, followed by the shared socioeconomic pathway of climate change scenario and VIC model parameters. Plain Language Summary: The Tarim River is the largest inland river in China, which is an arid area with the ecosystem primarily sustained by water from melting snow and glaciers in the headstream area. Compared with long‐duration drought, flash drought is more difficult to forecast and identify. We used the variable infiltration capacity model to build a hydrological model of the headstream area of the Tarim River Basin, and the model output (ET data) was used to identify flash droughts. Based on 10 representative Coupled Model Intercomparison Project Phase 6 (CMIP6) models, this study projected the future flash droughts in the study area under climate change. The findings indicated that the alpine region is likely to experience a greater frequency and intensity of flash droughts in the future (2021–2100) compared to the plain region. Compared with the historical period (1961–2014), the frequency, duration, and intensity of flash droughts tend to increase throughout the study area, especially for the alpine area. In addition, the result of uncertainty decomposition revealed that the CMIP6 model is the most important uncertainty source for flash drought projection. Key Points: The hydrological processes of study area are well described by the variable infiltration capacity model and Bayesian uncertainty analysisCompared with the plain region, the alpine region has higher flash drought frequency and intensity in the futureThe Coupled Model Intercomparison Project Phase 6 model is the most important uncertainty source for flash drought projection [ABSTRACT FROM AUTHOR]

Understanding the runoff response to climate change in the Tibetan Plateau (TP) is critical to water resources management since TP is the "Water Tower of Asia" and is sensitive to climate change. However, previous studies have paid more attention to the changes in annual and monthly runoff. Therefore, the changes in the characteristics of floods and droughts are still unknown, particularly in the Yarlung Zangbo River basin (YRB) in the southern TP. Therefore, this study simulates the runoff in four subbasins in the YRB using the GR4J_SNOW model to depict the characteristics (including frequency, severity, peak, and duration) of floods on a daily scale and those of droughts on a monthly scale. It is done in historical (1979–2014) and future (2049–2084) periods under different climate scenarios (RCP4.5 and RCP8.5), and then the changes in floods and droughts between the two periods are comprehensively compared. The results indicate that the YRB has experienced marginal streamflow change during the historical period. Under future varying climate change scenarios, however, the YRB might become wetter with increasing frequency, volume, and peak of floods, along with decreasing frequency, severity, and duration of droughts. In the upstream YRB, covered by more snow with a drier climate, the flood and drought characteristics appear to be more sensitive to climate change than in the downstream YRB. This study is helpful for a better understanding of the hydrological process in the TP under climate change and for forming sustainable water resource strategies for the surrounding regions of the TP. Plain Language Summary: The Tibetan Plateau (TP) is the Asian water tower, providing water resources to hundreds of millions of people living downstream. The Yarlung Zangbo River basin (YRB), located in the southern part of the TP, has attracted increasing attention because most of the Tibetan people live there and it is the upper stream of the Brahmaputra River. It is not clear how floods and droughts, the two most serious natural disasters, could change under climate change in the YRB. This study simulates the changes in flood and drought characteristics in the YRB in the historical (1979–2014) and future (2049–2084) periods under different climate scenarios (RCP4.5 and RCP8.5). Our results show that the YRB could become wetter with increasing floods and mitigated droughts in the future, despite minor changes in flood and drought characteristics in the historical period. The change could be stronger upstream than downstream. This study can be helpful for long‐term water resource management and planning on the TP. Key Points: The characteristics of floods and droughts in the Yarlung Zangbo River basin (YRB) are comprehensively analyzed in the past and futureThe YRB is expected to become wetter in the future, reflected by increased floods and alleviated droughtsThe flood and drought characteristics in its drier upstream are more sensitive to climate change than those in the humid downstream [ABSTRACT FROM AUTHOR]

This study examines August droughts in northern China (north of 35°N) at interannual and interdecadal timescales. During the period from 1968 to 1992, the precipitation in the western and eastern regions of northern China showed an out‐of‐phase pattern. During the period from 1994 to 2018, the climate in the Tarim Basin became wetter, but there was no significant connection with drought in North China. Further studies demonstrated that the Atlantic sea surface temperature (SST) and regional soil moisture anomalies were related to drought changes in northern China. Before the early 1990s, the east‐west standardized precipitation index dipole mode in northern China was physically linked with the wet soil in central Asia in the preceding June; moreover, the wet land surface could persist until August and cause anticyclonic and cyclonic systems over Mongolia and the subtropical northwestern Pacific, thus contributing to precipitation surplus in northwest China and a deficit in North China. After the early 1990s, however, wet conditions over the Tarim Basin were related to wet soil in the East European Plain in the preceding July: the wet soil could persist into August and generate anomalous circulation over the Tarim Basin, leading to abnormal humidity. Additionally, the SST conditions in the North (South) Atlantic are key sources of climate predictability for northern China drought at the interseasonal scale after (before) the early 1990s. Key Points: The spatial distribution of the standardized precipitation index in northern China shows a marked zonal dipole patternThe drought in northern China underwent a remarkable interdecadal change in approximately 1992The Atlantic sea surface temperature and regional soil moisture anomalies were responsible for the drought changes in northern China [ABSTRACT FROM AUTHOR]

Risks associated to extreme hydrological conditions, such as floods and droughts, are expected to increase in future climate because of projected changes in precipitation and temperature. Assessing how wet and dry persisting conditions (or spells) will evolve in future climate is a crucial step in the study of extreme hydrological events. Projected changes over the north‐eastern part of North America in the annual number of wet days, wet, and dry spells characteristics (number, duration), and wet spells intensities are analyzed. Two regional climate model ensembles are considered: the multimember ensemble from the Canadian RCM v5 (CRCM5‐LE), and 16 simulations from the NA‐CORDEX multimodel ensemble both using the Representative Concentration Pathway 8.5 (RCP8.5) scenario. Comparison of observed and simulated wet and dry spells characteristics is first performed in present climate (1971–2000). Regional Climate Model (RCM)s tend to generate too many wet days and wet or dry spells resulting in shorter dry spells and slightly longer wet spells. Modeling uncertainties are accounted for a bigger contribution to the bias than internal variability since the multimodel ensemble dispersion is the largest. Throughout the 21st century, both ensembles project significant trends in winter at higher latitudes resulting in increasing wet day frequency, increasing number of wet spell, longer wet spells and shorter dry spells. For other seasons, internal variability of the CRCM5‐LE and differences among the various NA‐CORDEX simulations seems to overwhelm the climate change signal. Wet spell intensities increases are projected for all seasons over almost the entire domain. Globally, wetter climate with potential significant hydrological impacts are expected in many regions. Key Points: Wet and dry spells future evolution are assessed using two RCMs ensemble: CRCM5‐LE and NA‐CORDEXModeling uncertainties are accounted for a bigger contribution to the bias than internal variabilityBoth internal variability and modeling uncertainties seems to overwhelm the climate change signal [ABSTRACT FROM AUTHOR]

The standardized precipitation evapotranspiration index (SPEI) is one of the well‐established drought metrics worldwide. It is simply computed using precipitation and atmospheric evaporative demand (AED) data. Although AED is considered a key driver of drought variability worldwide, it could have less impact on drought in specific regions and for particular times as a function of the magnitude of precipitation. Specifically, the influence of the AED might overestimate drought severity during both normal and humid periods, resulting in "false alarms" about drought impacts on physical and human environments. Here, we provided a global characterization of the sensitivity of the SPEI to changes of the AED. Results demonstrate that the contribution of AED to drought severity is largely impacted by the spatial and temporal variability of precipitation. Specifically, the impact of AED on drought severity was more pronounced during periods of low precipitation, compared to wet periods. Interestingly, drought severity in humid regions (as revealed by SPEI) also showed low sensitivity to AED under drier conditions. These results highlight the skill of SPEI in identifying the role of AED in drought evolution, especially in arid and semiarid regions whose climate is characterized typically by low precipitation. This advantage was also evident for humid environments, where SPEI did not overestimate drought severity due to the increased AED. These findings highlight the broader applicability of SPEI to accurately characterize drought severity worldwide. Key Points: Atmospheric Evaporative Deamdn mostly affect SPEI in dry periodsThere are spatial differences in the influence of the AED on drought assessment by means of the SPEIAED is not overestimating drought severity since it shows a comprehensive influence on dryness [ABSTRACT FROM AUTHOR]

The reliable projection of future changes in hydrological drought characteristics plays a crucial role in providing meaningful insights into agricultural development and water resources planning under climate change. In this study, we develop probabilistic projections of hydrological drought characteristics through a convection‐permitting climate simulation and a multimodel hydrological prediction for two major river basins in South Texas of the United States. The probabilistic hydrological drought projection depicts the future evolution of spatiotemporal characteristics of droughts under best‐ and worst‐case scenarios. Our findings reveal that there is a considerable variation in hydrological drought regimes near the urban area in South Texas. And the prolonged severe drought events are expected to be punctuated by the increasing extreme precipitation in a changing climate. This could lead to an increasing number of the dry‐wet abrupt alternation events. Moreover, hydrological droughts are projected to occur more frequently for the fall season in the Guadalupe River Basin and for the winter season in the Blanco River Basin, advancing our understanding of future changes in seasonal characteristics of hydrological droughts at a river basin scale. Key Points: Probabilistic projections of hydrological drought characteristics are developed at a river basin scaleHydrological droughts are expected to occur more frequently by the end of the 21st centuryThe number of dry‐wet abrupt alternation event is projected to increase in a changing climate [ABSTRACT FROM AUTHOR]

Probabilistic projections of future drought characteristics play a crucial role in climate change adaptation and disaster risk reduction. This study presents a copula‐based probabilistic framework for projecting future changes in multivariable drought characteristics through convection‐permitting Weather Research and Forecasting simulations with 4‐km horizontal grid spacing. A probabilistic multivariate drought index is introduced to examine the joint effects of drought indicators with uncertainty intervals for four major river basins located in South Central Texas of the United States. Markov chain Monte Carlo is used to address uncertainties in assessing copula parameters and in predicting climate‐induced changes in hydrological regimes. Our findings reveal that the severity and intensity of drought episodes can be amplified when considering the compound effects of soil moisture and runoff regimes by using the probabilistic multivariate drought index. The South Central Texas region is projected to experience more drought events with shorter duration and higher intensity in a changing climate. The drought severity will not necessarily increase due to the decreasing drought duration. In addition, our findings indicate that the intensity of future droughts is expected to increase as a result of the deficiency of soil moisture even though precipitation extremes are projected to become more frequent. Moreover, climate change impacts on multivariate drought characteristics will intensify with the increasing temporal scales (i.e., short‐, medium‐, and long‐term droughts) although the number of future drought events may decrease by the end of this century. Plain Language Summary: Projecting future changes in drought characteristics plays a crucial role in climate change adaptation and disaster risk reduction. Here we present a copula‐based probabilistic framework for conducting high‐resolution projections of multivariable drought characteristics through convection‐permitting Weather Research and Forecasting simulations with the 4‐km horizontal grid spacing. A probabilistic multivariate drought index is also introduced to examine the joint effects of drought indicators for four major river basins located in South Central Texas of the United States. Our findings reveal that the severity and intensity of drought episodes can be amplified when considering the compound effects of soil moisture and runoff regimes. Furthermore, the long‐lasting droughts are expected to evolve into a series of short‐duration droughts due to the projected increase in the frequency and intensity of extreme precipitation in a changing climate. This study provides meaningful insights into the evolution of future drought characteristics in view of the increasing trend in extreme precipitation, which plays an important role in facilitating sustainable agricultural development and water resources planning under climate change. Key Points: A copula‐based probabilistic framework was proposed for conducting high‐resolution projections of multivariate drought characteristicsHigh‐resolution climate projections were developed using the convection‐permitting WRF model with the 4‐km horizontal grid spacingA probabilistic multivariate drought index was introduced to examine joint effects of soil moisture and runoff deficits [ABSTRACT FROM AUTHOR]

A severe drought hit the Greater Horn of Africa (GHA) in 2014, but it remains unclear whether this extreme event was attributable to anthropogenic climate change or part of longer‐term natural cycles. Precipitation patterns are known to be changing across the GHA, but trajectories in land surface variables are much less well known. We simulated the GHA land surface environment to assess the balance between natural cycles and human‐induced climate change. Using a new form of event attribution study where we focused on both climate variables and also directly simulated land surface variables, we combined publicly volunteered distributed computing with land surface simulations to quantify land surface responses. Uncertainty was quantified both for climate model and land surface model outputs. We identified two distinct "drought trajectories" in the GHA bimodal seasonality area during the March–May (Long Rains season) of 2014. Human‐induced climate change may have resulted in regions from Lake Nalubaale (Lake Victoria) to Northern Kenya receiving less precipitation in this season and having up to 20% higher probability of drought‐level evapotranspiration rates (increasing drought). In contrast, the simulated anthropogenic climate change signal for this season induced somewhat wetter conditions and up to 20% lower probability of drought‐level evapotranspiration in Eastern Ethiopia, Southern Somalia, and coastal Kenya (decreasing drought). Uncertainties in our modeling system varied by region and variable of focus, but broadly we found that land surface simulation uncertainty neither added significantly to climate model uncertainty nor significantly reduced it. Key Points: Precipitation patterns are known to be changing across the Horn of Africa, but trajectories in land surface variables are less well knownWe identify two distinct "drought trajectories" in the Horn of Africa: one of increasing drought and one of decreasing droughtChanges in water cycle impacts may best be assessed through attribution studies that include changes in land surface variables [ABSTRACT FROM AUTHOR]

The arid/semiarid region of Northwest China (NWC, north to 35°N, and west to 100°E in China) experienced significant wetting after the late 1980s. We used both the summer precipitation and standardized precipitation indices (precipitation index [PI] and standardized precipitation index) to reexamine the regime shift. Consistent with the rainfall, the drought condition represented by the standardized precipitation index was significantly alleviated over most areas of NWC during P2 (1989–2016) than that during P1 (1961–1988). Along with the increased rainfall over the NWC, significant changes also occur in the interannual variation‐related circulation. The Ural High (UH) was found to be closely related with the interdecadal change during the late 1980s. The NWC PI‐related wave propagation from the UH weakened after the late 1980s. The persistent tropical Indian Ocean sea surface temperature (SST) from the preceding winter to the summer were also found to influence the NWC PI through modulating the South Asian High during P1. However, during P2, the ENSO signals in the preceding winter, which can be memorized by the Indian Ocean SST in the spring and propagate to the Indo‐Pacific SST in the summer, can influence the NWC PI. The wave train pattern in the convection from the Maritime Continent to NWC and northwestern Europe seems to be a key bridge. The UH seems to be independent of the above SST‐forced atmospheric circulations. The SST signals of the preceding winter can provide useful information for the summer drought prediction in NWC. Key Points: The summer drought over Northwest China (NWC)‐related atmospheric circulation show significant changes at the late 1980sThe Ural High's impact on the atmospheric circulation over NWC becomes much weaker during P2 (1989‐2016) than that during P1 (1961‐1988)The key SST regions related with the NWC drought shifted from the tropical Indian Ocean during P1 to the Indo‐Pacific region during P2 [ABSTRACT FROM AUTHOR]

We perform the first uncertainty quantification analysis of the turn‐of‐the‐century drought in the western United States using a large perturbed‐parameter ensemble of the Community Atmosphere Model version 4.0 (CAM4). We develop several metrics to characterize the aridity bias, spatial extent, and tropical forcing of the drought and use statistical models to ascertain that the modeled drought was mainly sensitive to CAM4 parameters related to deep convection and clouds. Deep convection parameters account for over half the variance across the drought metrics. We employ observed estimates of these drought metrics to infer probability distributions of the model parameters that lead to a better agreement with observations, thereby providing guidance on how to improve the simulation of drought in CAM4. We find that in some cases, the suggested parameter values that improve the simulation of one drought characteristic would degrade the simulation of another, suggesting that there is a complex relationship between the model parameters and drought in the western United States. We also demonstrate reductions in the uncertainty of the drought metrics of up to 30% by constraining with observations of all metrics. Furthermore, we demonstrate for the first time that improvements to the simulation of the spatial extent of the turn‐of‐the‐century drought also lead to improvements in the spatial extent of the Australian Millennium drought, suggesting that physics of drought as encoded by the model parameters may be generalizable. Key Points: Deep convection parameters account for more than half the CAM4 ensemble variance in metrics used to quantify droughtWe found optimal parameter values that may lead to a better reproduction of drought in CAM4We reduce the uncertainty of the CAM4 simulation of a metric that quantifies the spatial extent of drought by 40% [ABSTRACT FROM AUTHOR]

Studying the tendency of soil temperature and moisture can provide scientific support for setting soil parameters for land surface hydrological model. Previous research has shown that there is long‐range correlation of soil temperature or moisture; however, driving factors of long‐range correlation variations and the cross correlation between temperature and moisture under multiple timescales have rarely been discussed. To explore the driving factors, we compared long‐range correlation between shady and sunny slopes. Adaptive fractal analysis was utilized to analyze long‐range cross correlation (LRCC) and long‐range correlation (LRC). Experimental data were collected between 9 August 2013 and 3 December 2014 at A'rou observation stations, Babao River Basin. Results show that two slopes have some common characteristics. (1) Soil temperature and moisture display the consistent change. (2) The persistence intensity of moisture, temperature, and their interaction intensity change at 9, 6, and 6‐day timescales, respectively. (3) LRC and LRCC indices demonstrate the stratification heterogeneity. Results also show that LRC and LRCC indices on two slopes have differences. The soil system was stratified into three layers to explain these differences over large timescales. (1) At 4‐ to 20‐cm depth, with significant influence of solar radiation and evapotranspiration on sunny slope, moisture shows weaker persistence. There is stronger antipersistence of temperature and stronger hydrothermal interaction on sunny slope. (2) At 20‐ to 80‐cm depth, there is weaker persistence of soil moisture on shady slope because of unstable groundwater and side runoff supply. (3) At 80‐ to 160‐cm depth, with seasonal melt‐water effect on sunny slope, persistence of moisture was considerably weaker. Key Points: Comparison of long‐range correlations of soil moisture between the shady slope and sunny slope. Comparison of long‐range correlations of soil temperature between the shady slope and sunny slope. Comparison of long‐range cross correlation between the soil moisture and soil temperature between the shady slope and sunny slopeLong‐range correlation and long‐range cross correlation display vertical depth variation and timescale variationWe seek out driving factors of stratification heterogeneity of LRC and LRCC in different soil depths [ABSTRACT FROM AUTHOR]

Drought is the most recurrent and destructive hazard in arid and semiarid regions and will only become more complex under climate change. It is vital to characterize the various types of drought, to investigate the potential factors affecting different types of drought, and to assess the relationship between drought types. In this study, the Standardized Precipitation Index and the Standardized Runoff Index were used to characterize meteorological and hydrological drought, respectively, to investigate drought characteristics and mechanisms in 17 catchments on the Loess Plateau from 1961 to 2013. Furthermore, the propagation time from meteorological to hydrological drought was explored and the potential factors influencing drought propagation time were investigated. The results indicate that the Loess Plateau has experienced an increased tendency toward both meteorological and hydrological droughts over the period 1961–2013, with hydrological drought more serious than meteorological drought at various drought assessment time scales. Moreover, average drought duration and severity were greater for hydrological drought than meteorological drought. Maximum 5‐day precipitation (Rx5day) was the dominant extreme climate index for explaining variance in meteorological drought at the annual time scale. Owing to the greater complexity underlying hydrological drought, Rx5day, the number of warm days (Tx90p), and the number of warm nights (Tn90p) all contribute to the variance in hydrological drought. Furthermore, the percentage of forested land had a significant positive association (p < 0.001) with propagation time, whereas the percentage of land given over to pasture had a significant negative association (p < 0.001) with propagation time. Key Points: Loess Plateau has experienced an increased tendency toward both meteorological and hydrological droughts over the period 1961–2013Average drought duration and severity were greater for hydrological drought than meteorological droughtChanges in land use and land cover can alter the propagation time from meteorological to hydrological drought [ABSTRACT FROM AUTHOR]