Future discharge drought across climate regions around the world modelled with a synthetic hydrological modelling approach forced by three General Circulation Models

Abstract. Hydrological droughts characteristics (drought in groundwater and streamflow) likely will change in the 21st century as a results of climate change. Magnitude and directionality of these changes and their dependency on climatology and catchment characteristics, however, is largely unknown. In this study a conceptual hydrological model was forced by downscaled and bias-corrected outcome from three General Circulation Models for the A2 emission scenario (GCM forced models), and the WATCH Forcing Data re-analysis dataset(reference model). The threshold level method was applied to investigate drought occurrence, duration and deficit volume. Results for the control period (1971–2000) show that the drought characteristics of each GCM forced model reasonably agree with the reference model for most of the climate types, suggesting that the climate model's results after post-processing produce realistic outcome for global drought analyses. For the near future (2021–2050) and far future (2071–2100) the GCM forced models show a decrease in drought occurrence for all major climates around the world and increase of both average drought duration and deficit volume of the remaining drought events. The largest decrease in hydrological drought occurrence is expected in cold (D-)climates where global warming results in a decreased length of the snow season and an increased precipitation. In the dry B-climates the smallest decrease in drought occurrence is expected to occur, which probably will lead to even more severe water scarcity. However, in the extreme climate regions (desert and polar), the analysis for the control period showed that projections are in these regions most uncertain. On a global scale the increase in hydrological drought duration and severity will lead to a higher impact of drought events, which urges water resources managers to timely anticipate on the increased risk on more severe drought in groundwater and streamflow and to design pro-active measures.

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Future discharge drought across climate regions around the world modelled with a synthetic hydrological modelling approach forced by three general circulation models

Natural Hazards and Earth System Science ◽

10.5194/nhess-15-487-2015 ◽

2015 ◽

Vol 15 (3) ◽

pp. 487-504 ◽

Cited By ~ 23

Author(s):

N. Wanders ◽

H. A. J. Van Lanen

Keyword(s):

General Circulation ◽

Reference Model ◽

Control Period ◽

General Circulation Models ◽

Hydrological Drought ◽

Drought Duration ◽

Data Set ◽

Drought Characteristics ◽

The World ◽

Drought Occurrence

Abstract. Hydrological drought characteristics (drought in groundwater and streamflow) likely will change in the 21st century as a result of climate change. The magnitude and directionality of these changes and their dependency on climatology and catchment characteristics, however, is uncertain. In this study a conceptual hydrological model was forced by downscaled and bias-corrected outcome from three general circulation models for the SRES A2 emission scenario (GCM forced models), and the WATCH Forcing Data set (reference model). The threshold level method was applied to investigate drought occurrence, duration and severity. Results for the control period (1971–2000) show that the drought characteristics of each GCM forced model reasonably agree with the reference model for most of the climate types, suggesting that the climate models' results after post-processing produce realistic outcomes for global drought analyses. For the near future (2021–2050) and far future (2071–2100) the GCM forced models show a decrease in drought occurrence for all major climates around the world and increase of both average drought duration and deficit volume of the remaining drought events. The largest decrease in hydrological drought occurrence is expected in cold (D) climates where global warming results in a decreased length of the snow season and an increased precipitation. In the dry (B) climates the smallest decrease in drought occurrence is expected to occur, which probably will lead to even more severe water scarcity. However, in the extreme climate regions (desert and polar), the drought analysis for the control period showed that projections of hydrological drought characteristics are most uncertain. On a global scale the increase in hydrological drought duration and severity in multiple regions will lead to a higher impact of drought events, which should motivate water resource managers to timely anticipate the increased risk of more severe drought in groundwater and streamflow and to design pro-active measures.

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Uncertainties in runoff projection and hydrological drought assessment over Gharesu basin under CMIP5 RCP scenarios

Journal of Water and Climate Change ◽

10.2166/wcc.2020.088 ◽

2020 ◽

Vol 11 (S1) ◽

pp. 145-163 ◽

Cited By ~ 1

Author(s):

S. M. Ashrafi ◽

H. Gholami ◽

M. R. Najafi

Keyword(s):

River Basin ◽

General Circulation ◽

General Circulation Models ◽

Hydrological Drought ◽

Drought Severity ◽

Historical Period ◽

Drought Duration ◽

Rcp Scenarios ◽

Drought Assessment ◽

Drought Characteristics

Abstract Hydrological drought plays an important role in planning and managing water resources systems to meet increasing water demands due to population growth. In this study, the effects of climate change on the hydrological drought characteristics of the Gharasu basin, as one of the major sub-basins of the Karkheh river basin, are investigated. This river basin has experienced severe droughts, and floods, in recent years. The uncertainties in projected drought conditions are characterized based on a suite of 34 general circulation models (GCMs). Based on hydrological simulations over the historical period, 12 GCMs are selected to estimate projected runoff values and the corresponding streamflow drought index (SDI) in the future period. The ‘run theory’ is applied to evaluate the drought characteristics under Representative Concentration Pathways (RCPs) 4.5 and 8.5 emission scenarios. Results show that uncertainties of drought projection under RCP8.5 are higher than under RCP4.5, where among different drought characteristics, the maximum uncertainty is detected for drought severity and maximum drought duration. Moreover, the uncertainty of drought projection in wet periods is greater than that in dry periods.

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Extreme Drought Events over the Amazon Basin: The Perspective from the Reconstruction of South American Hydroclimate

Water ◽

10.3390/w10111594 ◽

2018 ◽

Vol 10 (11) ◽

pp. 1594 ◽

Cited By ~ 6

Author(s):

Beatriz Garcia ◽

Renata Libonati ◽

Ana Nunes

Keyword(s):

Surface Temperature ◽

Extreme Events ◽

General Circulation ◽

Amazon Basin ◽

General Circulation Models ◽

Extreme Drought ◽

Severe Drought ◽

South American ◽

Spatial And Temporal Patterns ◽

Near Surface

The Amazon basin has experienced severe drought events for centuries, mainly associated with climate variability connected to tropical North Atlantic and Pacific sea surface temperature anomalous warming. Recently, these events are becoming more frequent, more intense and widespread. Because of the Amazon droughts environmental and socioeconomic impacts, there is an increased demand for understanding the characteristics of such extreme events in the region. In that regard, regional models instead of the general circulation models provide a promising strategy to generate more detailed climate information of extreme events, seeking better representation of physical processes. Due to uneven spatial distribution and gaps found in station data in tropical South America, and the need of more refined climate assessment in those regions, satellite-enhanced regional downscaling for applied studies (SRDAS) is used in the reconstruction of South American hydroclimate, with hourly to monthly outputs from January 1998. Accordingly, this research focuses on the analyses of recent extreme drought events in the years of 2005 and 2010 in the Amazon Basin, using the SRDAS monthly means of near-surface temperature and relative humidity, precipitation and vertically integrated soil moisture fields. Results from this analysis corroborate spatial and temporal patterns found in previous studies on extreme drought events in the region, displaying the distinctive features of the 2005 and 2010 drought events.

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Hydrological drought across the world: impact of climate and physical catchment structure

Hydrology and Earth System Sciences ◽

10.5194/hess-17-1715-2013 ◽

2013 ◽

Vol 17 (5) ◽

pp. 1715-1732 ◽

Cited By ~ 111

Author(s):

H. A. J. Van Lanen ◽

N. Wanders ◽

L. M. Tallaksen ◽

A. F. Van Loon

Keyword(s):

Large Scale ◽

Hydrological Drought ◽

Temperate Climate ◽

Minor Effect ◽

Hydrological Models ◽

Drought Duration ◽

Groundwater System ◽

Drought Characteristics ◽

The World ◽

Groundwater Systems

Abstract. Large-scale hydrological drought studies have demonstrated spatial and temporal patterns in observed trends, and considerable difference exists among global hydrological models in their ability to reproduce these patterns. In this study a controlled modeling experiment has been set up to systematically explore the role of climate and physical catchment structure (soils and groundwater systems) to better understand underlying drought-generating mechanisms. Daily climate data (1958–2001) of 1495 grid cells across the world were selected that represent Köppen–Geiger major climate types. These data were fed into a conceptual hydrological model. Nine realizations of physical catchment structure were defined for each grid cell, i.e., three soils with different soil moisture supply capacity and three groundwater systems (quickly, intermediately and slowly responding). Hydrological drought characteristics (number, duration and standardized deficit volume) were identified from time series of daily discharge. Summary statistics showed that the equatorial and temperate climate types (A- and C-climates) had about twice as many drought events as the arid and polar types (B- and E-climates), and the durations of more extreme droughts were about half the length. Selected soils under permanent grassland were found to have a minor effect on hydrological drought characteristics, whereas groundwater systems had major impact. Groundwater systems strongly controlled the hydrological drought characteristics of all climate types, but particularly those of the wetter A-, C- and D-climates because of higher recharge. The median number of droughts for quickly responding groundwater systems was about three times higher than for slowly responding systems. Groundwater systems substantially affected the duration, particularly of the more extreme drought events. Bivariate probability distributions of drought duration and standardized deficit for combinations of Köppen–Geiger climate, soil and groundwater system showed that the responsiveness of the groundwater system is as important as climate for hydrological drought development. This urges for an improvement of subsurface modules in global hydrological models to be more useful for water resources assessments. A foreseen higher spatial resolution in large-scale models would enable a better hydrogeological parameterization and thus inclusion of lateral flow.

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Residual Mass Severity Index (RMSI) – a duration free method to characterise droughts

10.5194/egusphere-egu2020-6317 ◽

2020 ◽

Author(s):

Rounak Afroz ◽

Ashish Sharma ◽

Fiona Johnson

Keyword(s):

Climate Change ◽

General Circulation ◽

Severity Index ◽

General Circulation Models ◽

Drought Indices ◽

Severe Drought ◽

Monthly Precipitation ◽

Water Shortages ◽

Simple Method ◽

Residual Mass

The complexity of representing droughts has led to many drought indices being developed. A common aspect for many of these indices, however, is the need to adopt a predefined time period, over which a drought is characterized. Therefore, to declare a catchment as drought-impacted, 6, 12 or 24-month SPI are required. Actual water allocations, however, are required at all times and are thus duration free; a concept well described by the well-known residual mass curve. Here we propose a new framework to characterize drought, termed as the Residual Mass Severity Index (RMSI). As the name suggests, the RMSI defines drought based on the magnitude of the residual mass in any location which is calculated by performing a water balance using a prescribed demand. Demand here is adopted as the median monthly precipitation for the region. Water shortages only become significant when there is a sustained deficit compared to this demand. The above described residual mass is standardized to formulate the RMSI across Australia. The new RMSI has been validated against established drought indices (such as the SPI) to highlight the advantages of a duration-free drought index.RMSI provides a simple method of assessing sustained and severe drought anomalies which is important with expected increases in water scarcity due to anthropogenic climate change. We demonstrate that RMSI can be used as a tool to evaluate the performance of General Circulation Models (GMCs) in representing the sustainability of water resource systems as a product of resilience, reliability, and vulnerability (RRV) of the system. Future projections of drought from GCMs which perform well in representing RMSI in the RRV context in the historical climate are then compared to drought projections from the full CMIP5 ensemble.Keywords: Drought, Residual Mass Curve, SPI, RRV, Climate Change, CMIP5 GCMs

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A generic method for hydrological drought identification across different climate regions

Hydrology and Earth System Sciences ◽

10.5194/hess-16-2437-2012 ◽

2012 ◽

Vol 16 (8) ◽

pp. 2437-2451 ◽

Cited By ~ 41

Author(s):

M. H. J. van Huijgevoort ◽

P. Hazenberg ◽

H. A. J. van Lanen ◽

R. Uijlenhoet

Keyword(s):

Land Surface ◽

Threshold Level ◽

Global Scale ◽

Hydrological Drought ◽

Dry Period ◽

Drought Duration ◽

Variable Threshold ◽

The World ◽

Level Method ◽

Zero Runoff

Abstract. The identification of hydrological drought at global scale has received considerable attention during the last decade. However, climate-induced variation in runoff across the world makes such analyses rather complicated. This especially holds for the drier regions of the world (both cold and warm), where, for a considerable period of time, zero runoff can be observed. In the current paper, we present a method that enables to identify drought at global scale across climate regimes in a consistent manner. The method combines the characteristics of the classical variable threshold level method that is best applicable in regions with non-zero runoff most of the time, and the consecutive dry days (period) method that is better suited for areas where zero runoff occurs. The newly presented method allows a drought in periods with runoff to continue in the following period without runoff. The method is demonstrated by identifying droughts from discharge observations of four rivers situated within different climate regimes, as well as from simulated runoff data at global scale obtained from an ensemble of five different land surface models. The identified drought events obtained by the new approach are compared to those resulting from application of the variable threshold level method or the consecutive dry period method separately. Results show that, in general, for drier regions, the threshold level method overestimates drought duration, because zero runoff periods are included in a drought, according to the definition used within this method. The consecutive dry period method underestimates drought occurrence, since it cannot identify droughts for periods with runoff. The developed method especially shows its relevance in transitional areas, because, in wetter regions, results are identical to the classical threshold level method. By combining both methods, the new method is able to identify single drought events that occur during positive and zero runoff periods, leading to a more realistic global drought characterization, especially within drier environments.

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Global Coupled General Circulation Models

Bulletin of the American Meteorological Society ◽

10.1175/1520-0477-76.6.951 ◽

1995 ◽

Vol 76 (6) ◽

pp. 951-957 ◽

Cited By ~ 18

Author(s):

Gerald A. Meehl

Keyword(s):

General Circulation ◽

Research Programme ◽

General Circulation Models ◽

Coupled Modeling ◽

Coupled Modelling ◽

Climate Research ◽

The World ◽

The Status ◽

Coupled General Circulation Models ◽

La Jolla

Major conclusions and recommendations regarding the status of global coupled general circulation models are presented here from a workshop convened by the World Climate Research Programme Steering Group on Global Coupled Modelling that was held from 10 to 12 October 1994 at the Scripps Institution of Oceanography, La Jolla, California. The purpose of the workshop was to assess the current state of the art of global coupled modeling on the decadal and longer timescales in terms of methodology and results to identify the major issues and problems facing this activity and to discuss possible alternatives for making progress in light of these problems. This workshop brought together representatives from nearly every group in the world actively involved in formulating and running such models. After presentations by workshop participants, four working groups identified key issues involving 1) initialization and model spinup, 2) strategies and techniques for coupling of model components, 3) flux correction/adjustment, and 4) secular drift and systematic errors. The participants concluded that improved communication between those engaged in this activity will be important to enhance further progress. Consequently, the World Climate Research Programme intends to continue the support of internationally coordinated activities in global coupled modeling.

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Climate Change Effects on Spatiotemporal Patterns of Hydroclimatological Summer Droughts in Norway

Journal of Hydrometeorology ◽

10.1175/2011jhm1357.1 ◽

2011 ◽

Vol 12 (6) ◽

pp. 1205-1220 ◽

Cited By ~ 31

Author(s):

Wai Kwok Wong ◽

Stein Beldring ◽

Torill Engen-Skaugen ◽

Ingjerd Haddeland ◽

Hege Hisdal

Keyword(s):

Climate Change ◽

General Circulation ◽

Dominant Role ◽

Summer Precipitation ◽

Meteorological Drought ◽

Threshold Level ◽

General Circulation Models ◽

Drought Duration ◽

Drought Characteristics ◽

The Impact

Abstract This study examines the impact of climate change on droughts in Norway. A spatially distributed (1 × 1 km2) version of the Hydrologiska Byråns Vattenbalansavdelning (HBV) precipitation-runoff model was used to provide hydrological data for the analyses. Downscaled daily temperature and precipitation derived from two atmosphere–ocean general circulation models with two future emission scenarios were applied as input to the HBV model. The differences in hydroclimatological drought characteristics in the summer season between the periods 1961–90 and 2071–2100 were studied. The threshold level method was adopted to select drought events for both present and future climates. Changes in both the duration and spatial extent of precipitation, soil moisture, runoff, and groundwater droughts were identified. Despite small changes in future meteorological drought characteristics, substantial increases in hydrological drought duration and drought affected areas are expected, especially in the southern and northernmost parts of the country. Reduced summer precipitation is a major factor that affects changes in drought characteristics in the south while temperature increases play a more dominant role for the rest of the country.

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Comparison of Projection in Meteorological and Hydrological Droughts in the Cheongmicheon Watershed for RCP4.5 and SSP2-4.5

Sustainability ◽

10.3390/su13042066 ◽

2021 ◽

Vol 13 (4) ◽

pp. 2066

Author(s):

Jin Hyuck Kim ◽

Jang Hyun Sung ◽

Eun-Sung Chung ◽

Sang Ug Kim ◽

Minwoo Son ◽

...

Keyword(s):

General Circulation ◽

Drought Index ◽

Standardized Precipitation Index ◽

Coupled Model ◽

Meteorological Drought ◽

General Circulation Models ◽

Hydrological Drought ◽

Drought Indices ◽

Drought Period ◽

Drought Characteristics

Due to the recent appearance of shares socioeconomic pathway (SSP) scenarios, there have been many studies that compare the results between Coupled Model Intercomparison Project (CMIP)5 and CMIP6 general circulation models (GCMs). This study attempted to project future drought characteristics in the Cheongmicheon watershed using SSP2-4.5 of Australian Community Climate and Earth System Simulator-coupled model (ACCESS-CM2) in addition to Representative Concentration Pathway (RCP) 4.5 of ACCESS 1-3 of the same institute. The historical precipitation and temperature data of ACCESS-CM2 were generated better than those of ACCESS 1-3. Two meteorological drought indices, namely, Standardized Precipitation Index (SPI) and Standardized Precipitation Evapotranspiration Index (SPEI) were used to project meteorological drought while a hydrological drought index, Standardized Streamflow Index (SDI), was used to project the hydrological drought characteristics. The metrological data of GCMs were bias-corrected using quantile mapping method and the streamflow was obtained using Soil and Water Assessment Tool (SWAT) and bias-corrected meteorological data. As a result, there were large differences of drought occurrences and severities between RCP4.5 and SSP2-4.5 for the values of SPI, SPEI, and SDI. The differences in the minimum values of drought index between near (2021–2060) and far futures (2061–2100) were very small in SSP2-4.5, while those in RCP4.5 were very large. In addition, the longest drought period from SDI was the largest because the variation in precipitation usually affects the streamflow with a lag. Therefore, it was concluded that it is important to consider both CMIP5 and CMIP6 GCMs in establishing the drought countermeasures for the future period.

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Volcanic hazard exacerbated by future global warming–driven increase in heavy rainfall.

10.31223/x5z906 ◽

2021 ◽

Author(s):

Jamie Farquharson ◽

Falk Amelung

Keyword(s):

Global Warming ◽

General Circulation ◽

Heavy Rainfall ◽

Spatial Scales ◽

General Circulation Models ◽

Volcanic Hazards ◽

Volcanic Arcs ◽

Increased Risk ◽

Future Global Warming ◽

Wide Range

Heavy rainfall drives a range of eruptive and noneruptive volcanic hazards; over the Holocene, the incidence of many such hazards has increased due to rapid climate change. Here we show that extreme heavy rainfall is projected to increase with continued global warming throughout the 21st century in most subaerial volcanic regions, dramatically increasing the potential for rainfall-induced volcanic hazards. This result is based on a comparative analysis of nine general circulation models, and is prevalent across a wide range of spatial scales, from countries and volcanic arcs down to individual volcanic systems. Our results suggest that if global warming continues unchecked, the incidence of primary and secondary rainfall-related volcanic activity—such as dome explosions or flank collapse—will increase at more than 700 volcanoes around the globe. Improved coupling between scientific observations—in particular, of local and regional precipitation—and policy decisions, may go some way towards mitigating the increased risk throughout the next 80 years.

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