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Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | ect sustainable ff 3) have increased by 1,2 − < , and J. Yin 1,2 ected more than 2 billion people on a global ff 6704 6703 , T. L. Qin 1,2 , H. Wang 1,2 , D. H. Yan 1,2 This discussion paper is/has beenSystem under Sciences review (NHESS). for Please the refer journal to Natural the Hazards corresponding and final Earth paper in NHESS if available. State Key Laboratory of Simulation and Regulation of Water CycleDepartment in of River Water Basin, Resources, China China Institute of Water Resources and Hydropower level (United Nations International StrategySince for the Disaster 1970s, the Reduction areas Secretariat, where 2009). droughts happened (PDSI regions to quantify thecoping impact with of drought drought, issue. consequently, to make decisions regarding 1 Introduction With the increasinghappens impact in of more climatecaused change areas more than and with 11 million anthropogenic higher deaths, and activities, frequency. a drought Since 1990, drought disasters have eralized drought severity (GDS)GDT, were the calculated GDD, by and theorydrought, the of severe runs. GDS drought, Application of andthe of various extreme the centers drought) drought of to levels gravitychange the (i.e. with of period mild time. them The 1960–2010 drought, proposed are shows methodology moderate all helps that water distributed managers in in water-stressed the middle reached of DRB, and assessment index (GDAI) basedevents. The on GDAI water considersdrological resources water model. supply system We and demonstrate for the waterbasin assessing use (DRB) demand of drought in using the the a proposed northeastpared index distributed China. to in hy- The observed the results drought Dongliao simulated disastertion river by records of the in drought GDAI DRB. events are As andare then second, the com- compared the spatial temporal with distribution distribu- ofThen, the drought generalized traditional drought frequency times approach from (GDT), the generalized (i.e. drought GDAI duration the (GDD), SPI, and gen- the PDSI, and the RWD). Drought is firstly aaster resource issue. issue, The and occurrencesdomness. with of Drought drought its events issue development usually it haseconomic feature transforms and become determinacy into social one and development. a ran- of In dis- this the paper, major we propose factors the to generalized a drought Abstract 1 Institute of Water Resources2 and Hydropower Research, 100038, Beijing, China Research, 100038, Beijing, China Received: 14 May 2014 – Accepted: 29Correspondence May to: 2014 B. – S. Published: Weng 4 ([email protected]) November 2014 Published by Copernicus Publications on behalf of the European Geosciences Union. Generalized drought assessment in Dongliao river basin based onresources water system B. S. Weng Nat. Hazards Earth Syst. Sci.www.nat-hazards-earth-syst-sci-discuss.net/2/6703/2014/ Discuss., 2, 6703–6746, 2014 doi:10.5194/nhessd-2-6703-2014 © Author(s) 2014. CC Attribution 3.0 License. 5 25 20 10 15 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | ecting sustainable eco- ff ected by persistent drought severely ff from 1950 to 2010, which were 2.19 ected areas (the areas that crop yields 2 ff km 8 1964), drought indices could be divided into 6706 6705 10 ∼ × ected by the characteristics of water cycle of region or ff and 0.10 2 km 8 10 × Since 1900, a number of indices have been developedDuring to the quantify germination a stage drought, which (1900 Drought is firstly a resource issue which is shortage of water resources, and with its The drought issue has become one of the major factors a The drought areas and drought intensity in China are showing an increasing trend. It et al., 2003). Drought indices in this stage were established based on a single factor four types. Firstly,Munger they index were (Munger, 1916), createdmenstock, Kincer 1942), based index standard on (Kincer, deviation(McQuigg, 1919), index the 1954). (Xu, Blumenstock Secondly, precipitation they 1950), index were antecedent records, (Blu- createdas precipitation based such moisture on index the adequacy as evaporation index records,based such (McGuire on and the Palmer, precipitation 1957).covitch, Thirdly, and 1930), they temperature and were records, Demartonne created suchated index as (De based Marcovitch Martonne, on index 1926). the (Mar- Fourthly, they precipitation were and cre- evaporation records, such as aridity index (Ma basin. It is characterizednormal by precipitation the continuously. shortage Coping with of droughtciple water should of obviously resources the follow resulted the natural-artificial from prin- water the cycle. below- could be classified into three stages: germination, growth and development. nomic and social development. Governmenthave taken departments, more the attention public to the andchanging evolution environment, researchers law and and to driving coping mechanism withhot of it. topics drought In in in addition, the the it field is of one of hydrology the and front water issues resources. development and it transforms into ain water disaster cycle. issue. Its Drought evolution is is one a of the extreme events happened frequently in Chinaand (Qin, Chongqing 2009), in such 2006wheat as (Qin, region the 2009), in drought northern thesouthern occurred China metrological China in in drought in Sichuan 2008 2009 occurred (Qin, (Wengmiddle in and 2009), and Yan, the the lower 2010) winter Yangtze and extreme River the drought in severe 2011. occurred drought in occurred in the relatively abundant water resources. In recent years, several extreme drought events northern China with shortage of water resources, but also in the southern China with eastern China showed by historical1730 records. and Drought disasters from happened 1900 from tillThe 1500 areas now to where have drought a events widethe and range middle drought of 21st disasters century. distribution occurred The have specificallydecreased annual increased (Dai, by average since over 2011). a 10 % thancrop normal annual yields yields) and decreased damaged by areaswere (the over nearly areas 30 that % 0.21 thantimes and normal 1.77 annual times of yields) theand of impacts Drought of drought flood Relief disasters disasters respectively Headquarters, (State Flood 2010). Control Drought occurs frequently not only in the (Intergovernmental Panel on Climate Change, 2012). has the same trend as(Qin, the 2009). global. Severe Drought drought issue hasYan, 2010). has happened Over become every the more 2 past and to 500 more years, 3 obvious several years large-scale on drought average disasters (Weng occurred and in in Africa in themainly characterized 1980s with global (Kallis, warming, 2008).and the stability Given the of the climate impacts system growing of2011). was influence Special reducing, drought Report of and on climate Managing otherClimate the change Risks Change extreme of Adaptation climate Extreme showed Events events thatof Disasters were drought to the would Advance increasing world be (Dai, persistent inand in the the many future United regions owing States,Africa Southern to and other Europe, evaporation countries increase Southeast and Asia, and regions would Brazil, soil be Chile, a moisture Australia decrease, and the southern US in thethe late analysis 19th of century the reconstructed anderage precipitation 20th annual series century economic (Le has losses Quesne that increased, etto resulted indicated 8 al., from by billion 2009). drought dollars. The disasters It av- in reachedAgency, US 1995). up range to The from 40 drought-related 6 billion disasters in caused 1988 more (Federal Emergency than Management 500 thousand deaths 1.5 times in the world (Dai et al., 2004). The probability of drought events occurred in 5 5 25 20 10 15 25 20 10 15 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | 2 er- ff records, ff erence between the GDAI, the SPI, ff 6708 6707 1992), drought indices could also be divided into ∼ DRB is controlled by the Pacific low and Siberian high with obvious four seasons. The This study is organized as follows. Section 2 describes the methodology, includ- During the development stage (1993 till now), with the development of computers During the growth stage (1965 precipitation is decreasing from upper toitation lower is reaches, and reduced multi-year average from precip- 710 to 450 mm from 1960 to 2011. It is distributed unevenly 600 m, where soil primarily consistsare of dark the brown segment soil from and Erlongshan planosol;station the Reservoir middle as downwards reaches to a Chengzishang hilly hydrological black area with soil altitude and from meadowhydrological 100 soil; station to the downwards 300 m, lower to whereLine reaches Sanjiangkou soil as Iron are primarily a Bridge the consists plain in of segmentmeadow area Siping-Qiqihar soil, from with salinized Railway Chengzishang chernozem altitude soil from and zero steppe to aeolian 200 sandy m, soil. where soil primarily consists of 2.1 Case study Dongliao River Basin (DRB)(Fig. is 1). It located is in roughlyabove northeastern divided Erlongshan into Reservoir China. as three Its a segments. area low-mountain The and is upper hilly reaches 11 area 306 are km with the altitude segment from 200 to Palmer drought severity index (PDSI)tion and rate 3 of presents water deficitgeneralized the (RWD) drought results, (Sect. duration 2.5). including (Sect. Sec- of the 3.2), Dongliao generalized the River Basin. generalized drought Section drought 4the times assesses severity PDSI the (Sect. and (Sect. di the 3.1), 3.3) RWD. The the study concludes in Sect. 5. 2 Methodology water stress index (Ghulam et al., 2007c). ing the water andthe energy method transfer of process generalizedof model drought runs in (Sect. assessment Dongliao 2.4), index river and (GDAI) basin the (Sect. assessment (Sect. 2.3), method 2.2), of the standard theory precipitation index (SPI), b), standard vegetation index (Peters et al., 2002), shortwave infrared perpendicular ply water index (Mo et al., 2006), perpendicular drought index (Ghulam et al., 2007a, were assessed (Francesco etindices al., can 2009; compute Shiau on(McKee and various et time Modarres, al., scales, 2009). 1993).multiple like Some They indices, such standard drought could as precipitations be comprehensiveteorological drought index divided index (SPI) drought (GB/T into index 20481-2006, three 2006), (Yanthe types. me- et distributed Firstly, al., they hydrological 2009). integrated model,geomorphology Secondly, such based they hydrological were as model created Palmer (Xubased et based drought on remote al., on severity sensing, 2008). such index Thirdly, as2001), they vegetation-temperature based condition were temperature–vegetation index on created dryness (Wang et index al., (Sandholt et al., 2002), vegetation sup- cesses with some physical mechanism to some degree. and hydrological models, drought indicescle, but not also only integrated contained multiple multi-factorsent indices of drought (GB/T water 20481-2006, parameters cy- 2006). which Furthermore, included di intensity, duration, severity and spatial extent index (Liu and Wei,such 1989). as Secondly, hydrological drought they severity were index (Dracupindex created et (Shafer based al., and 1980a), on surface Dezman, water the 1982). supply ation, runo Thirdly, such they took as surface Keetch-Byraminertia conditions drought into index index consider- (Wang (Keetch andwater and balance Guo, Byram, principle, 2003). such 1968), Fourthly,Palmer as soil revised they Palmer surface-water thermal supply drought were index severity created (Garen, indexwere 1993). established based (Palmer, Drought based 1965, indices on on in 1967), multi-factors, and this the considered stage soil water cycle elements and pro- But the universality and the mechanism of water cycle werefour lacked. types. Firstly, theyas were precipitation also anomaly percentage created1972), drought index based area (National on index Meteorological (Bhalme the and Center precipitation Mooley, of 1980), records, positive CMA, and such negative anomaly or two-factors, in accordance with the particular region. They were simple to calculate. 5 5 20 25 15 10 25 20 10 15 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | cients are also ffi cients are all over from 1960 to 2000 C. The evaporation ffi ◦ ective evapotranspi- ff ff 4.89 % in Quantai hydro- − ciency coe ffi ciency coe ffi e model e ff e model e ff 6710 6709 records of Erlongshan reservoir, Wangben, Quan- ff records of Wangben, Quantai, Liaoyuan hydrological cients are all over 0.70, and it is up to 0.812 in Erlong- ff ffi is decreasing from upper to lower reaches, and multi-year ff from 2006 to 2010 (Table 4), the result shows that the maximum . ff ff ciency coe ffi reduces from 150 to 25 mm, that from June to September accounts for 7.91 % in Liaoyuan hydrological station and the minimum one is 2.90 % ff − is: DW (1) D − e model e from 1960 to 2000 (Table 3), the result shows that the maximum deviation is ff ff SW Overall, the simulation accuracy of WEP-DRB has reached the requirement to obtain Comparing the simulated and observed restoring monthly runo = 6.32 % in Quantai hydrological station and the minimum one is 0.47 % in Erlongshan D 2.3 Generalized drought assessment index DRB is an important productionand base forest of land commodity account grain.DRB for The 88.03 areas are %. of chosen Therefore, cultivated agricultural to land the system sum be and of evaluated. them. ecosystem Then Water in ration supply water and (SW) demand represents special sum (DW) water of per resourcesshortage surface per assessment e assessment unit unit is in DRB. The water resources all over 0.70, and it is up to 0.763 ingood Wangben simulation hydrological results. station. Thedemand model of can water be resourcesindex used system (Yan et to to al., simulate calculate 2014). water the supply generalized and drought water assessment shan reservoir hydrological station.runo Comparing the simulated− and observed monthly reservoir hydrological station. Nash–Sutcli 0.70, and it is up toobserved 0.830 daily in runo Quantai hydrological station.deviation Comparing is the simulated and in Wangben hydrological station. Nash–Sutcli period is from 2006 to 2010. (Table 2), the resultlogical shows station that and the the maximum minimumSutcli one deviation is is 2.90 % in Wangben hydrological station. Nash– station from 2001 to 2010. The warm-up period is from 2001 to 2005, and the verified and the verified periodby is from using 1960 observed to daily 2000. runo Secondly, WEP-DRB model is validated socio-economic data (Table 1). They arebefore treated inputting by the spatial model. interpolation and formatting 2.2.2 Model verification and validation DRB is divided into eleventime catchments and step sixty-four of assessment units. WEP-DRBserved The and is simulated restoring one monthly day. runo tai Firstly, hydrological WEP-DRB station model from is 1956 verified to 2000. by The using warm-up ob- period is from 1956 to 1959, 2.2.1 Model input WEP-DRB model input dataland consists use of data, six meteorological types, i.e. and digital hydrological elevation data, data, hydraulic soil engineering data, data, and average runo 80 % of annual runo 2.2 Water and energy transfer processWater model and in DRB energy transferthe process elements model of natural in and DRB artificialand water (WEP-DRB) water cycle, is demand and then chosen of todetails to the calculate of simulate the assessment WEP-DRB water units can supply be based found on in water the studies resources by system. Jia More et al. (2001). precipitation, and that of Julychange and is decreasing August from accounts west for toto 50 east. northwest, %. The and Inter-annual temperature multi-year is precipitation average decreasing valuesis from reduce increasing southwest from from 6.7 upper to to 5.6 850 lower to reaches, 1200 and mm. multi-year The average runo values change from within the year, of which, that from June to September accounts for 75 % of annual 5 5 25 20 10 15 20 25 15 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | , 2 (3) during . More 2 2 S is the DI , though it . “h” is not ) + 2 1 ected areas 1 1 X ff X erent assess- S − ff i = ( , though there is 1 S is considered here X 1, K + indicates a cumulative 2 S D DI is defined by taking log- + DI is less than is expressed in ten days dur- − 1 DI is more than − D D − = SW is the ten days average water D DI is more than during 1 to 28 June 2000. The yields − 2 and the disaster areas (the areas that , say 2 2 which accounted for 70 % during 2 July to D 2 is: th ten days, respectively; DI 6712 6711 i Z and 1 0.5 . D are thresholds of the GDAI. For mild drought, they D + 2 ) | X D | / ) (2) 0 25.0 (4) K , and / between 2.8) ) 1 i 1 ( X + | × X , Z D 0 | ) were compared with the observed drought disaster records from ( + X SW is the DI, Z for the 4 ) be used to compare water resources shortage in di erent assessment periods, the correct index 1 / 36 1 ) 1) ff X i ( / − . “p” is a drought event because 0 DW i 1 Z ected by drought disaster starting from 18 April 1994. The a K (( X ff , ) × 10 i 1)th ten days. The classification of drought-wet still follows the standard of is the average absolute ( which accounted for 63 % during 21 April to 16 May 1997. They accounted | − 2 D DW is the ten days average water demand; i | 0.91DI( D · = 1.6log 329.37 K ) i = ( = Figure 3 shows that “g” is a drought event because Comparing the results evaluated by GDAI and the observed drought disaster records The observed drought disaster records in Gongzhuling city were listed below. The To verify the reasonability and representativeness of the GDAI, the results simulated The water resources shortage index The observed drought disaster records in Lishu County were listed below. Maize = 0 deficiency of a drought parameterarithm below of the the critical GDAI. level. are 0, 1.0, 2.0;are for 2.0, moderate 3.0, 4.0; drought, for they extreme are drought, they 1.0, are 2.0, 3.0,a 3.0; 4.0, drought 5.0, for event respectively. severe because drought,is the they more GDD than is onlyone one unit unit of and GDD below details can be found in the studies by Lu et al. (2010). alized drought severity (GDS)Feng are and calculated Zhu, 1997). by The theory generalizeding drought of duration which runs a (Dracup drought etit parameter al., is is 1980b; continuously the below timeis the critical the period level. positive between In run-length. the other The words, initiation generalized and drought termination severity of a drought event. That 8 June to 30 July20 1997. July They 2000. were 667 km in Lishu county (Fig. 2a)able and to Gongzhuling assess city the (Fig. characteristics 2b), of we droughts could in see DRB. 2.4 that the GDAI is Theory of runs Generalized drought times (GDT), generalized drought duration (GDD), and gener- for 88 % until 30were July reduced 1997. 70 They % were until 2440 9 km August 2000. damaged areas of thecrop maize yields decreased were by 1200 km over 80 % than normal annual yields) were 300 km In order to let Eq. ( Palmer drought severity index (Palmer, 1965), as shown in Table 5. by GDAI using Eq. ( ment units and di by referencing for the PDSI. That is: K Where, Z Then, the generalized drought assessment index (GDAI) DI is: DI Where, DI for the ( growth was a account for 30 % inand 25 the June yields 1994. were The1133 km decreased damaged by areas 10 of % the during maize 11 were May 1487 km to 12 June 1996. They were supply; 1960 to 2010 in Gongzhuling city and Lishu county in DRB. K 5 5 25 15 20 10 15 10 20 25 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | ∼ erences are that the RWD erent periods (i.e. 1960s, ff ff erent drought levels (i.e. mild drought, erence is also compared from 1999 to ective evapotranspiration, it equals to ff ff ff 6714 6713 100 cm) at the beginning of the month is 150 mm (Liu et al., ∼ erence between the results assessed by the GDAI, the SPI, the PDSI and ff The method of the SPI can be found on Zhang and Gao (2004) and Yuan and Zhou The SPI for 1 and 12 month time scales, the PDSI for 1 month, and the RWD for 2000s, respectively. For moderate drought, it movedand toward southeast southeast, northwest, from east, the 1960s to the 1970s, the 1970s to the 1980s, the 1980s to the 2000s, respectively. 3.2 Distribution of the generalized droughtThe duration centers of gravityalso of all distributed the in the MGDD middlegravity of reached moved of various toward DRB southeast, (Fig. drought 5). northwest, levelsto For southeast, mild in the drought, and various the 1970s, northwest center periods the of from 1970s are the to 1960s the 1980s, the 1980s to the 1990s, and the 1990s to the 1980s, the 1980s to the 1990s,drought, and the the center 1990s to of thethough gravity 2000s, it respectively. moved moved For moderate toward toward northwest southeastmoved from toward from southeast the the from 1990s the 1960s to1970s 1960s the to to to 2000s. the the the For 1990s, 2000s. 1970s, severe then Forsoutheast drought, toward extreme it from northwest drought, the from it 1960s the moved to toward the southwest, 1970s, northwest, the and 1970s to the 1990s, and the 1990s to the 3.1 Distribution of the generalized droughtThe times centers of gravitydistributed of in the the GDT middle reached ofdrought, of various the DRB drought (near center levels Erlongshan of in reservoir)The gravity (Fig. various reason 4). moved periods may For toward are mild be southeastin all that from lower the the reaches. GDT 1960s It in to moved upper the toward reaches 1970s. southwest, are east, increasing and while west decreasing from the 1970s to the For the GDD or(MGDS) GDS of of each various unit drought wasGDD calculated levels, or the firstly. GDS Assessment maximum was units GDDof greater were sixty-four (MGDD) than chosen assessment or or when units equal their GDS inculated. to five the decades. minimum Then, of their average centers MGDD of or gravity MGDS were cal- equal to the minimum of average GDT of sixty-four assessment units in five decades. 1970s, 1980s, 1990s, 2000s) weredrought compared levels, with assessment each units other. For were the chosen GDT when of their various GDT were greater than or water supply here didspecial water not resources. consider surface e 3 Results According to the resultsbution simulated of by the GDT, the the GDAImoderate GDD, and and drought, the theory severe GDS of drought, of runs, di extreme the drought) spatial in distri- di method (GB/T 20481-2006, 2006). The20 cm) available moisture at stored the inunderlying beginning surface of levels layer (0 (20 the month2004). The is method 40 of mm, the RWD andis is similar defined the to as available the the GDAI. moisture ratio The stored di of the in water resources shortage and the water demand, and the 1–ten days of sixty-four assessmentannual units from di 1960 to 2010the are RWD calculated. is The compared. inter- Moreover,2001 the annual because di DRB has occurred continuously drought disasters in(2004a). this period. The method(2004b) of and the GB/T 20481-2006 PDSI (2006). can The evaporation be is estimated found by Thornthwaite’s on Palmer (1965), Yuan and Zhou The GDAI is“natural-artificial” constructed dualistic water based cyclestandard on process. precipitation It the index is (SPI), elementsrate evaluated the of by of water Palmer comparing deficit water drought with (RWD). severity resources the index system (PDSI) and and the 2.5 SPI, PDSI and RWD 5 5 25 20 10 15 25 20 10 15 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | - ffi 6716 6715 erences between the GDAI and the SPI are listed as follows (Table 6). Firstly, ff The di ements of water cyclehydraulic (i.e. engineering). precipitation, Though evaporation, the soiland SPI it water, considered and is the water constructed precipitation.sidered supply based Thirdly, water for of on water supply resources natural (i.e. system,water water resources) the surface cycle and GDAI water water con- demand resources,the (i.e. groundwater SPI agricultural did system resources, and not and ecosystem). consider Though, soil water resources system. for driving forces, the GDAI considered theanthropogenic influence of climate natural climate change variability (NCV), (ACC),draulic engineering underlying regulation conditions (HER), changeNCV though (UCC), and the and SPI ACC. Secondly, just hy- structed for considered based water the cycle on influence “natural-artificial” processes of and water cycle elements, processes. the And GDAI it is considered con- the el- steady and the latterexpresses wet are spell changed in greatly. winter. The Figurethan results 10 the calculated shows by GDAI the that12 SPI month the during for 1 are SPI month crop also for are greater cult growth 1 greater month to than periods. evaluate the the The annualcan GDAI, results distribution express however, of their the calculated drought characteristic changeJune events. by of is The and two the stable. GDAI in drought and It Gongzhuling SPI disasters thebetter city is happened SPI than for in di in the both July SPI. Lishu 2000. country But the in results simulated by the GDAI are 4.1.1 Temporal distribution Figures 8 and 9 showerally that the greater results than simulated the by the GDAI SPI during for drought 1 and periods. 12 Though month are the gen- former are changed 4.1 The GDAI vs. the SPI 4 Discussion Temporal distribution of drought(Fig. events 7) and simulated spatial byThe distribution the drought GDAI of frequency was was drought the compared ratio frequency rence with of and the the the months SPI, total or ten number thewhen days of PDSI, a of months drought drought and or events event the occur- ten was RWD. days. equal The to month or or greater ten than days mild was drought. chosen southeast from thethe 1960s 2000s, to respectively. the Forsoutheast, 1970s, severe and the drought, northwest 1970s it from1980s to moved the to the toward the 1960s 1980s, 1990s, southwest, to andmoved and northwest, the the toward the 1970s, 1990s northwest, the 1980s to northeast, the1980s 1970s to and to 2000s, to southeast the respectively. For the 1990s, from extreme and 1980s, the drought, the the 1960s 1990s it to to the the 2000s, 1980s, respectively. the 3.3 Distribution of the generalized droughtThe severity centers of gravity of theall MGDS of distributed various in drought levels the ingravity various middle moved periods toward reached are southeast, also of northwest,to DRB southeast, the (Fig. and 1970s, 6). northwest the from For2000s, 1970s the respectively. mild For to 1960s drought, moderate the drought, the it 1980s, center moved the toward of 1980s southeast, northwest, to and the 1990s, and the 1990s to the direction of the centeris of short gravity is from the similar 1960s toand to mild southeast the drought, from 1970s. but the For thebut extreme 1960s the movement drought, to movement distance it distance the moved is 1970s toward short.1980s southwest and It to moved the the toward 1990s 1970s northwest and to and the southeast the 1990s from 1980s to the the respectively, 2000s respectively. 1990s, and the 1990s to the 2000s, respectively. For severe drought, the movement 5 5 20 10 15 20 10 15 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | erences of drought ff erent times, Palmer ff erent underlying conditions, ff ), and chose weather data of western K cult to express the spatial distribution of ffi erent places and at di ff cient ( 6718 6717 ffi erent soil types and di erent soil types. Thirdly, for water resources system, ff ff erent things at di ff erences between the GDAI and the PDSI are listed as follows (Table 6). ected by human activities, especially hydraulic engineering regulation. ff ff . The evaporation is estimated by Thornthwaite’s method which only considered erent locations is the same. So it is di ff ff erences of drought frequency of sixty-four assessment units are little; they changed The water resources shortage of the GDAI is expressed by water supply and water The di The GDAI is defined by considering water supply and water demand, as well as ff the GDAI no matter inter-annualters or at annual. Lishu The country RWD in can June express two and drought at disas- Gongzhuling city in July 2000, but the simulated di from 24 to 31 %.than the Figure GDAI 14 in shows Qintuntion that irrigation of the area Erlongshan results because reservoir. the simulated PDSI by did the not PDSI4.3 consider are the greater regula- The GDAI vs. the RWD Figures 15 and 16 show that the results simulated by the RWD are generally less than In order to compareassumed di the climatic characteristic coe Kansas, central Iowa, anddid northwestern not North consider Dakota the toand impact the correct. of influence However, di of the human PDSI activities, especially irrigation water supply. Therefore, the existing conditions. demand of water resources system.and The artificial GDAI water considered cycle, the though characteristicthe the of GDAI methods natural are of similar drought levels toevents and the a the PDSI. correct Therefore, index it of is more appropriate to4.2.2 evaluate drought Spatial distribution temperature and assumed that evaporationthan zero. equals This to assumption is zero unsuitable whenThe for DRB temperature available which is moisture temperature lower is stored lowdid in of the not the winter. consider PDSI the for impactthe the of PDSI entire di did DRB not took consider the water resources same system, value. but It the climatically appropriate for runo Secondly, for water cycle processesnatural and water elements, the cycle PDSI and is it constructed based considered on the precipitation, evaporation, soil water, and Figures 12 and 13than show the that the GDAI results duringdrought simulated of drought by the period, the PDSI is PDSI especiallyexpress more are two in serious generally drought than summer, greater disasters the thatby in GDAI. the is, June The GDAI and GDAI the are and July close intensity the 2000. to PDSI of the However, both the observed can drought results disasterFirstly, simulated records. for driving forces,did the not PDSI consider just the considered influence the of UCC influence and of HER, NCV especially and the ACC. irrigation It water supply. districts. Because their irrigation water supply of Erlongshan reservoir4.2 is less. The GDAI vs. the PDSI 4.2.1 Temporal distribution frequency of sixty-four assessment units are little; they changed fromthe 28 characteristics % of to topography, 34 soil %. considered and the vegetation irrigation per water assessmentspatial unit. supply distribution And of it of hydraulic also engineering. droughtchanged So frequency. from The it zero can drought express to frequencyhigher. the It 90 of % is assessment lower (Fig. in units 7).tion Lishu of irrigation The Erlongshan district reservoir. drought of Though frequency the it is lower of higher reaches in the because Shuangshan of upper and the Nanwaizi reaches regula- irrigation is The drought levels ofbution the of SPI precipitation are (Huangin et defined di al., according 2010). to Itdrought the events is (Yuan probability and assumed Zhou, density that 2004). distri- Figure the 11 drought shows that frequency the di 4.1.2 Spatial distribution 5 5 25 20 10 15 20 25 10 15 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | ects. ff ects natural and socio-economic ff ects of surface warming, J. Hydromete- ff ects and adapt his/her management ac- ff erences of them were analyzed from driving ff 6720 6719 ected by drought for a long time, and drought frequency ff This work was supported by the General Program of the National Natural The proposed drought assessment methodology gives a water manager a tool to To demonstrate this new drought assessment approach, a case study site on the Generalized drought times (GDT), generalized drought duration (GDD), and gen- drought properties through copulas, Phys. Chem. Earth, 34, 596–605, 2009. Water Resour. Res., 16, 289–296, 1980b. ing Safer Communities, Mitigation Directorate, Washington DC, 1995. 449–458, 1926. 16, 297–302, 1980a. for 1870–2002: relationship with soilorol., moisture 5, and 1117–1130, e 2004. bility, United States Department of Agriculture, Washington DC, 1942. Weather Rev., 108, 1197–1211, 1980. various periods. distinguish between naturalcordingly. and This would human imply e adapting to drought and reducing its a all distributed in the middle reached of DRB, and changed in various drought levels in of the centers ofGDS gravity (MGDS) of of the various GDT, the drought maximum levels GDD in (MGDD), various and periods the was maximum analyzed. They were of drought frequency from thethe GDAI SPI, were the compared PDSI, with andforces the the (i.e. RWD). traditional NCV, The ACC, approach di UCC, (i.e. oration, and HER), and water soil cycle water), elementswater water (i.e. cycle), precipitation, cycle water evap- supply processessoil (i.e. (i.e. water surface resources), natural water and water resources, water cycle demand groundwater (i.e. and resources, agricultural artificial and system anderalized ecosystem). drought severity (GDS) were calculated by theory of runs. The distribution has proposed the generalized droughtof assessment water index resources (GDAI) system from for assessing the drought perspective events. northeast China, the Dongliaorences, river basin was which studied. has Temporal high distribution frequency of of drought drought occur- events and spatial distribution over 80 % (Fig. 17). 5 Conclusion Drought is firstly a resource issuevelopment which it is transforms shortage into of a watersystems. disaster resources, The and issue occurrences with which of its a de- droughtness. events The usually basic feature principle determinacy of and natural-artificial random- water cycle should be followed. This study ter supply of the RWD consideredand surface water did resources not and consider groundwater resources, soilimportant water to resources agricultural (Table 6), systemthe however, soil RWD and water show ecosystem. that resources DRB are Therefore,of is the sixty-four a results assessment units simulated is by greater. The drought frequency of the entire DRB is results are more severe than the observed drought disaster records. Because the wa- Francesco, S., Brunella, B., Antonino, C., and Salvatore, G.: Probabilistic characterization of Feng, P. and Zhu, Y. S.: The identification of drought hazard, J. Nat. Disasters, 6, 41–47, 1997. Federal Emergency Management Agency: National Mitigation Strategy: Partnerships for Build- Dracup, J. A., Lee, K. S., and Paulson, E. C.: On the statistical characteristics of drought event, Dracup, J. A., Lee, K. S., and Paulson, E. G.: On the definition of droughts, Water Resour. Res., De Martonne, E.: Une nouvelle fonction climatologique: L’indice d’aridité, La. Meteorologie, 2, Dai, A. G., Trenberth, K. E., and Qian, T. T.: A Global Dataset of Palmer Drought Severity Index Dai, A. G.: Drought under global warming: a review, Clim. Change, 2, 45–65, 2011. Blumenstock, G. J.: Drought in the United States Analyzed by Means of the Theory of Proba- Bhalme, H. N. and Mooley, D. A.: Large-scale droughts/floods and monsoon circulation, Mon. for Basic Researchacknowledge of Yangwen Jia China for (Grant providing the No. WEP 2010CB951102). model. In addition, the authorsReferences gratefully Science Foundation of China (Grant No. 51279207) and the State Key Development Program Acknowledgements. 5 5 25 20 15 10 25 15 20 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | areas, Western Snow Conference, ff 6722 6721 perature/vegetation index space forEnviron., assessment 79, of 213–224, surface 2002. moisture status, Remote Sens. the severity ofReno, drought Nevada, April conditions 1982. in snowpack runo monitoring with NDVI-based Standardized68, 71–75, Vegetation 2002. Index, Photogramm. Eng. Rem. S., New York University Geophys. Res. Lab. Rep. TR-68-3, 32–56, 1967. production in China from 1950 to 1971, China Agriculture Press,DC, 1965. Beijing, 1972 (in Chinese). Sci. J., 36, 11–21, 1991. Weather Rev., 44, 642–643, 1916. copula function, Adv. Water Sci., 21, 188–193, 2010. California, 179–184, 1993. drought based on vegetation2006. supply water index, J. Nanjing Instit. Meteorol., 29, 396–402, severity model, J. Appl. Meteorol. Sci., 15, 207–216, 2004. ration to time scales, Eighth Conference on Applied Climatology, 17–22 January, Anaheim, United States, Mon. Weather Rev., 47, 624–631, 1919. variations in the Centraltree-ring Andes reconstructed of precipitation, Argentina Palaeogeogr. Palaeocl., and 281, Chile, 334–344, inferred 2009. from historicalScience Press, records Beijing, and 1989 (in Chinese). Rev., 85, 305–314, 1957. Asheville, NC: US Departmentiment Station, of 1968. Agriculture, Forest Service, Southeastern Forest Exper- recent 100 years, J. Geogr. Sci., 58, 69–74, 2003 (in Chinese). asters to AdvanceUK, Climate and Change New York, Adaptation, NY, USA., Cambridge 2012. University Press, Cambridge, Evolution characteristics of seasonal droughtbased in on the standardized south precipitation oftural index, Engineering, China Transactions 26, during of 50–59, the the 2010. past Chinese 58 years Society of Agricul- Beijing, 2006 (in Chinese). Geol., 52, 1045–1052, 2007a. a real-time drought monitoring method, ISPRS J. Photogramm., 62,for 150–164, 2007b. canopy water contentpendicular water estimation stress for index, Sci. highly China vegetated Ser. surfaces-shortwave D, 50, infrared 1359–1368, per- 2007c. Plan. Manage., 119, 437–454, 1993. Shafer, B. A. and Dezman, L. E.: Development of a surface water supply index (SWSI) to assess Sandholt, I., Rasmussen, K., and Andersen, J.: A simple interpretation of the surface tem- Qin, D. H.: Climate change and drought, Sci. Technol., 11, 7–8, 2009 (in Chinese). Peters, A. J., Walter-Shea, E. A., Ji, L., Vina, A., Hayes, M., and Svoboda, M. D.: Drought Palmer, W. C.: The abnormally dry weather of 1961–1966 in the northeastern United State, Palmer, W. C.: Meteorological Drought, Weather Bureau Research Paper No. 45, Washington National Meteorological Center of CMA: Severe weather overview and its impact on agricultural Munger, T. T.: Graphic method of representing and comparing drought intensities, Mon. Mohan, S. and Rangacharya, N. C. V.: A modified method for drought identification, Hydrolog. Mo, W. H., Wang, Z. H., Sun, H., Ma, L. J., and He, L.: Remote sensing monitoring of farmland Lu, G. H., Yan, G. X., Wu, Z. Y., and Kang, Y. X.: Regional drought analysis approach based on McQuigg, J.: A simple index of drought conditions, Weatherwise, 7, 64–67, 1954. Liu, W. W., An, S. Q., Liu, G. S., and Guo, A. H.: The farther modification of Palmer drought McKee, T. B., Doesken, N. J., and Kleist, J.: The relationship of drought frequency and du- Liu, C. M. and Wei, Z. Y.: Agricultural Hydrology and Water Resources in North China Plain, McGuire, J. K. and Palmer, W. C.: The 1957 drought in the eastern United States, Mon. Weather Le Quesne, C., Acuna, C., Boninsegna, J. A., Rivera, A., and Barichivich, J.: Long-term glacier Marcovitch, S.: The measure of droughtiness, Mon. Weather Rev., 58, p. 113, 1930. Keetch, J. J. and Byram, G. M.: AKincer, drought J. index B.: The for seasonal forest distribution fire of control, precipitation and Res. its Pap. frequency SE-38. and intensity in the Ma, Z. G., Hua, L. J., and Ren, X. B.: The extreme dry/wet events in northern China during Kallis, G.: Droughts, Annual Review of Environment and Resources, 33, 85–118, 2008. Intergovernmental Panel on Climate Change: Managing the Risks of Extreme Events and Dis- Huang, W. H., Yang, X. G., Li, M. S., Zhang, X. Y., Wang, M. T., Dai, S. W., and Ma, J. H.: Ghulam, A., Li, Z. L., Qin, Q. M., Tong, Q. X., Wang, J. H., Kasimu, A., and Zhu, L.: A method Ghulam, A., Qin, Q. M., and Zhan, Z. M.: Designing ofGhulam, the perpendicular A., drought Qin, index, Environ. Q. M., Teyip, T., and Li, Z. L.: Modified perpendicular drought index (MPDI): GB/T 20481-2006: Classification of Meteorological Drought, China Standard Publishing House, Garen, D. C.: Revised surface-water supply index for western United States, J. Water Resour. 5 5 30 25 20 15 10 30 20 25 15 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | records of ff , 2014. records of Erlongshan reser- ff Observed dailyWangben, runo Quantai, Liaoyuan hydrological station from 2006 toErlongshan 2010 manual reservoir in 1986 Hydrological yearbook operation in DRB Water resources integrated planning in China in 2006 Water resources bulletin in Songliao basin from 1990 to 2010 voir, Wangben, Quantai hydrological station from 1956 to 2000 1 : 250000 national fundamentalographic ge- information system 1 : 1000000 soilObserved database soil in data China MODIS, TM images2010 from 1980Observed to daily meteorological data of Kaiyuan,gliao, Siping, Changling,Qingyuan, Changchun, Meihekou station Panshi, Shuan- observed andruno restoring monthly 10.1007/s11069-014-1108-5 ff 6723 6724 ff tion sumption, irrigation schedule, etc. Daily runo 2005 ture, sunshine hours, relative humid- ity Monthly runo tion, digital river, catchment, etc. Model input data and their source. past 50 years and monitoring2004. and warning services in China, Sci. Technol. Rev., 7, 21–24, in China, Chinese J. Plant Ecol., 28, 523–529, 2004a. Earth Sci., 19, 982–991, 2004b. of generalized watershed droughtsources risk system, evaluation Nat. and Hazards, adaptive 73, strategy 259–276, based doi: on waterbased re- on PDSI and SPI, Water Resources and Hydropower Engineering, 40, 10–13, 2009. in Changing Environment, Chinese Hydraulic Engineering, 7, 4–7, 2010Chinese). (in Chinese). the Upper Yangtze, Yangtze River, 39, 1–5, 2008. remote sensing, Arid Meteorology, 21, 76–79, 2003 (in Chinese). in China, China Ministry of Water Resources, Beijing, 2010Report (in Chinese). on Disaster Riskfor Reduction, a Safer Risk Tomorrow, New and York, Poverty 2009. in a Changingtion Climate, for Invest drought Today monitoring, EditoralUniversity, 26, Board 412–419, of 2001. Geomatics and Information Science of Wuhan Iran, Meteorol. Appl., 16, 481–489, 2009. 5 Hydraulic engineering data6 Socio-economic data Distribution of reservoir and irriga- Water supply, water use, water con- 2 Soil data3 Land4 use data Meteorological and hydrological data Precipitation, wind speed, tempera- Soil depth, soil texture, etc. Land use data in 1954, 1986, 2000, National second soil survey data No. Type1 Digital elevation data Elevation, slope, aspect, flow direc- Name Description Table 1. Zhang, Q. and Gao, G.: The spatial and temporal features of drought and flood disasters in the Yuan, W. P. and Zhou, G. S.: Theoretical study and research prospect on drought indices, Adv. Yan, D. H., Weng, B. S., Wang, G., Wang, H., Yin, J., and Bao, S. J.: Theoretical framework Yuan, W. P.and Zhou, G. S.: Comparison between standardized precipitation index and Z index Xu, J. J., Yang, D. W., Lei, Z. D., and Huang, W.: A preliminary study on drought assessment in Yan, G. X., Lu, G. H., Wu, Z. Y., and Yang, Y.: Study on integrated meteorological drought index Xu, E. H.: The normality of the annual rainfall, Acta Meteorol. Sinica, 21, 17–34, 1950 (in Weng, B. S. and Yan, D. H.: Reflections on Integrated Coping Strategies for Drought in China Wang, X. P. and Guo, N.: Some research advances and methods on drought monitoring by United Nations International Strategy for Disaster Reduction Secretariat: Global Assessment Wang, P. X., Gong, J. Y., and Li, X. W.: Vegetation-temperature condition index and its applica- State Flood Control and Drought Relief Headquarters: Bulletin of flood and drought disasters Shiau, J. T. and Modarres, R.: Copula-based drought severity-duration-frequency analysis in 5 30 20 25 15 10 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | cient cient ffi ffi cient coe cient coe ffi e model Correlation ffi e model Correlation ff ff from 1960 to 2000. ff ciency coe ciency coe ffi ffi from 1960 to 2000. ff 4.89 0.805 0.937 6.32 0.830 0.937 − − ) (%) e 1 ) (%) e − 1 s − 3 s 3 (m (m ff ff 6726 6725 ) average runo 1 ) average runo − 1 s − s 3 3 (m (m ff ff Comparing the simulated and observed monthly runo Comparing the simulated and observed restoring monthly runo HydrologicalErlongshan reservoirWangben 157.21 Observed annualQuantai simulated annual 226.19 84.52 157.95 Deviation Nash–Sutcli 238.22 0.47 79.18 0.720 5.32 0.800 0.899 0.913 station average runo HydrologicalErlongshan reservoirWangben 166.16 Observed restoring annualQuantai simulated annual 282.99 Deviation Nash–Sutcli 91.56 171.98 291.20 3.50 87.08 0.812 2.90 0.775 0.932 0.900 station average runo Table 3. Table 2. Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | 4.0 4.0 4.0 cient 2.0 ffi ≤ − ≤ − ≤ − ≤ − cient coe 3.0 GDAI 3.0 RWD 3.0 PDSI ffi e model Correlation 1.5 SPI ff ≤ − ≤ − ≤ − ≤ − RWD PDSI GDAI SPI ciency coe < < < < ffi 4.0 4.0 4.0 2.0 − − − − from 2006 to 2010. ff 2.0 2.0 2.0 1.0 5.607.91 0.754 0.732 0.923 0.908 − − ≤ − ≤ − ≤ − ≤ − ) (%) e 1 − RWD GDAI SPI PDSI s 3 < < < < (m 3.0 3.0 1.5 3.0 ff 6728 6727 − − − − 1.0 1.0 1.0 0.5 ≤ − ≤ − ≤ − ≤ − ) average runo RWD GDAI SPI PDSI 1 − < < < < s 3 2.0 2.0 1.0 2.0 (m − − − − ff RWD GDAI SPI PDSI < < < < 1.0 1.0 0.5 1.0 Classification of the GDAI, SPI, PDSI, and RWD. Comparing the simulated and observed daily runo − − − − Hydrological Observedstation annualWangbenQuantai average simulated runo annualLiaoyuan 181.54 111.62 69.23 Deviation Nash–Sutcli 186.81 105.37 63.76 2.90 0.763 0.916 RWD Index Normal or wetGDAI spell Mild drought Moderate drought Severe drought Extreme drought SPI PDSI Table 5. Table 4. Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper |

and s

tation as a It is roughly from 1960 to mountain

. - ion is decreasing mm low

tem Precipitation, evaporation, soil water, and water supplyengineering of hydraulic groundwater resources as a (Figure 1) hydrological s

2 m ﬀ mm to 450 k

0 1 06 3 , m, where soil primarily consist 11

of dark brown soil and planosol; the

s 00 of black soil and meadow soil; the lower

soil water, and runo s area is annual precipitation change is decreasing from

- tation downwards to Sanjiangkou Iron Bridge in from zero to 2 China. It

5 ern 6730 6729 Location of study area. Precipitation Precipitation, evaporation, – – Agricultural system and ecosys- – – Surface water resources and

1. hydrological s m, where soil primarily consist Figure

m, where soil primarily consist

area with altitud 00

year average precipitation is reduced from 7 00 - plain oil and steppe aeolian sandy soil. s m m to 6

is located in northeast m m to 3

as a he upper reaches are the segment above Erlongshan Reservoir 00 200

. T (DRB)

hernozem from from 1 c ter, and water supplyengineering of hydraulic tem water resources, and soil water resources asin

tude

alinized s with altitude on, and that of July and August accounts for 50%. Inter

is distributed unevenly within the year, of which, that from June to September accounts for 75% of annual

Qiqihar Railway Line - It Elements Precipitation, evaporation, soil wa- Water demand Agricultural system and ecosys- . Case Study y y area . Methodology Location of study area. DRB is controlled by the Pacific low and Siberian high with obvious four seasons. The precipitat Dongliao River B 1 Comparing the GDAI with the SPI, the PDSI, and the RWD. from upper to lower reaches, and multi 2011 precipitati 2. 2. divided into three segments hill middle reaches are the segment from Erlongshan Reservoir downwards to Chengzishang hilly area with alti reaches are the segment from Chengzishang Siping meadow soil,

116 117 118 119 120 121 112 113 114 115 106 107 108 109 110 111 IndicesDriving forcesWater cycle ProcessesWater resources Water supply “Natural-artiﬁcial” water cycle Surface NCV, ACC, water UCC, resources, and ground- HER The GDAI Natural water cycle Natural water cycle NCV and ACC “Natural-artiﬁcial” NCV water and cycle ACC The SPI NCV, ACC, UCC, and HER The PDSI The RWD Figure 1. Table 6. . 2 is is 푆

the ) at

– 푆

= 푆 vaporation ,

20~100 ) 1 is in assessed by the

s The

+ 퐷 2(a)

The method of the (GDS) 2 The e

. 퐷 . ] drought ten days of sixty 6 length. + -

- (Figure Time Palmer drought severity mild drought, 1 of artificial” dualistic

- run 퐷

[200 2 2 the [2004a]

ounty = than normal annual In other words, it is S c

D .

퐷 ositive ity aged areas of the maize c 2006

D p . “natural - Lishu is not a drought event because ords (1960~2010). ords percent

haracteristics is a drought event because

say the p in c 1

” the GDAI. For 1 0

, ords s ” 8 h erence is also compared from 1999 to S

2 D

“ p of

ed in underlying levels ( rec 퐷 “ s . 1 . er er generalized drought severity Gongzhuling Gongzhuling diff over accounted for 70 percent during July

1 푋 (b) 푋 . That is

The generalized drought duration Yuan Yuan and Zhou

and . , and

hreshold GB/T 20481 which is drought inter-arrival time between difference between the results 1 t

2 than 퐷 annual and

L than m

listed below. The dam are ces system and

k , 1997]

(GDD)

and

2 he

month, and the RWD for 1 67 The available moisture stored in surface layer (0~20 ere 푋 ] of GDD and GDS. of GDD -

. more w annual ]

more - 6 [2004] is and ity

between . 1

]

2004b 푋 inter 200 10 [ 1 0 퐷퐼 , Feng and Zhu

, 6732 6731 1 푋 0 – GDAI and the observed drought disaster rec disaster drought observed and the GDAI

푋 Moreover, t that the GDAI is able to assess the standard precipitation index (SPI), 20

he observed drought disaster record The L the the [

. 2006 h

ongzhuling c are 1.0, 2.0, 3.0; for severe drought, they are 2.0, 3.0, 4.0; for extreme , 1980; -

the G and t

, though it is ecognition methods ecognition 2 in

during June 1 to 28, 2000. The yields were reduced 70 percent until August drought disasters in this period.

arrival time between (n+1)th drought and nth drought. and nth drought (n+1)th between time arrival , the PDSI for 1

he areas that crop yields decreased by

푋 - s 2 t es Zhang and Gao GDAI m Lu et al. of the GDAI.

k we could see

, generalized drought duration

compared. . , (RWD).

uan and Zhou

0 by )

4 8 to July 30, 1997. They were 6 ) Y areas ( Dracup et al. is indicates a cumulative deﬁciency of a drought parameter below the critical level.

[ (b ,

the elements of water resour 2 ] ounty GB/T 20481 Figure 3. R 3. Figure S 푆 (GDT) c the results evaluated by by evaluated results the [

D g eficit less than ed ty d Note: Parts in gray were the periods of the observed drought disast drought observed of the periods the were gray in Parts Note: evaluated disaster th drought. Lishu Lishu 1965 is continuously accounted for 63 percent during April 21 to May 16, 1997. They accounted for 88 percent is drought inter is drought

[ n (Figure

during which a drought parameter is continuously below the critical level (a) (a) during June

푳 respectively ater Compar 2 They were 2,4

ity , 퐷퐼 m w based on c theory of runs

month is 40 mm, and the available moisture stor k drought disaster record which and the –

s method month time scal is a drought event because

’ 2010). Note: parts in gray were the periods of the observed drought disaster 0 in the studies by 2

- 2 he results

0 ” Note: Note: m m ∼ Figure 2. 2. Figure k Palmer g k 12 occurred

“

and there is one unit of GDD below 0 ate of SPI can be found on

r 33 0 2 1 0 defined by taking logarithm Compared the results evaluated by the GDAI and the observed drought disaster

observed

Recognition methods of GDD and GDS. Note: X X X DI ) were 3 is

and . - Theory of Runs of Theory Gongzhuling the eneralized drought times

unit the . - is evaluated by comparing with be found G The Comparing t 4 constructed

퐷퐼 1 xpressed in ten days hough t are calculated by e the time period between the initiation and termination of generalized a drought drought severi event − they are 0, 1.0, 2.0; for moderate drought, they 2. until July 30, 1997. 9, 2000. were 1,2 yields 2 to July 20, 2000. and DRB were 1,1 It 1)th drought and

, . Thornthwaite can 1

shows that 푋 PDSI and RWD and PDSI

n by

Figure 3. Figure 2. records (1960 records. (

205 206 207 198 199 200 201 202 203 204 196 197 193 194 195 189 190 191 192 186 187 188 only one 、 the beginning of the than

SPI he SPI for . The method of The GDAI is T Figure 3 5 2001 because DRB has PDSI can be found on estimated cm) at assessment units from 1960 to 2010 are calculated GDAI, the SPI, the PDSI and the RWD 2. cycle process index (PDSI) and drought, they are 3.0, 4.0, 5.0 GDD is more More details

e th 1990s 1960s 1990s 1960s

the the the the , northwest, from

it moved toward

1990s, and . 1990s, and

. 2000s, respectively. For rd southeast the the iods t moved toward northwest I periods

the per

and southeast

1980s to various 1980s to

various riods are also all distributed in the 1990s to the the the (d) Extreme drought (d) Extreme (b) Moderate drought 90s 1980s, (d) Extreme drought Extreme (d) 1980s, (b) Moderate drought 60s 00s 60s the drought levels in the 70s

drought levels in

80s 80s 00s 70s 70s 90s 00s 1990s, and 2000s respectively. 80s 70s 90s erent drought levels in various periods. different 60s

the the 2000s, respectively. For severe drought, different 90s

1970s to 1970s to ﬀ 00s of

12 13 of erent drought levels in various periods.

60s D the ﬀ the the 80s 6734 6733 , GD M 1990s to 0s to 1980s to e 8 1970s 1970s, th 19 the the the the of various drought levels in various pe

S 1980s, For extreme drought, it moved toward southwest

. For mild drought, the center of gravity moved towa . For mild drought, the center of gravity moved toward southeast, northwest, 1990s and GDD of various drought levels in various periods are also all distributed in the 1960s to 1960s to the 1980s respectively, but the movement distance is short. M the moderate drought, it moved toward southeast, northwest, east, and southeast from the the patial distribution of the GDT 1980s, and direction of the center of gravity is similar to mild drought, but the movement distance 1970s. the patial distribution of the (a) Mild drought (a) Mild (a) Mild drought (a) Mild the For the (c) Severe drought (c) Severe (c) Severe drought (c) Severe (Figure 5) (Figure 6) . from Generalized Drought Duration Drought Generalized Generalized Drought Severity Drought Generalized 1970s to

1980s to 70s 70s 90s s to 90s Figure 4. S 60s the 1970s to 90s Figure 5. S movement the 70s 80s 90s 1970s to 1960 the 00s 70s the the 1970s, and 60s

80s 60s 80s the 80s 60s from 00s

00s 00s 1970s, 2000s, respectively 1970s 2000s, respectively. For moderate drought, it moved toward southeast, northwest, and southeast from Distribution of the the of Distribution Distribution of the the of Distribution

. . the the the Spatial distribution of the MGDD of di Spatial distribution of the GDT of di the The centers of gravity of the MGD The centers of gravity of the short 3 2 . . middle reached of DRB southeast, and northwest from to to 3 and southeast from to severe drought, the is 3 middle reached of DRB southeast, and northwest to 1960s to

262 263 264 265 266 267 268 269 260 261 254 255 256 257 258 259 250 251 252 253 Figure 5. Figure 4.

month are . - also greater

ountr c are the

greatly of drought ev

was chosen Lishu 1980s to generally greater than

month

- the simulated by the

are changed

. 1980s, d by the SPI for 1 Figure 7) the periods (

month - month or ten days happened in

s 2000s, respectively. better than the SPI. 12 various

The 1970s to annual distribution the calculate are the

and

- it moved toward northwest, northeast, and (d) Extreme drought 1 (b) Moderate drought and the latter are rought frequency 00s 1990s to

1970s, 60s 70s 90s drought levels in

the results the 70s 00s eady 60s 90s the GDAI st The drought frequency was the ratio of the months or ten different erent drought levels in various periods.

SPI for 80s . drought disaster calculated by the SPI for 12 ﬀ 80s of of months or ten days. 14

1960s to

S 1990s, and 6736 6735 GD the two the mber M For extreme drought, y y the

of changed results 15

1980s to are

the . The s and the total nu

1980s, patial distribution of the 2000s, respectively. (a) Mild drought (a) Mild the characteristic the SPI, the PDSI, and the RWD (c) Severe drought (c) Severe

the 90s the results simulated by occurrence stable. It is difficult to evaluate the 90s

00s results simulated b Figure 6. S is 70s 60s 1960s to 70s he 60s west, southeast, and northwest from 1990s to

. But the the expresses wet spell in winter. The . Though. the former 00s

that t s 80s

drought events

was compared with 80s crop growth period s of

emporal distribution of drought events and spatial distribution of d can express the T Spatial distribution of drought frequency simulated by the GDAI in DRB. Spatial distribution of the MGDS of di

. Discussion GDAI days 4 southwest, north 1990s, and southeast from month period - show

1 the SPI the Figure 7. Spatial distribution of drought frequency simulated by the GDAI in DRB. GDAI by the simulated frequency of drought distribution Spatial 7. Figure

both

was equal to or greater than mild drought. 273 274 275 276 277 278 270 271 272 ity in July 2000

istribution Figure 7. Figure 6. igure 9 D versus F event SPI for , however, their change and

drought emporal

T a The GDAI GDAI The

. Figure 8 1 . The GDAI and the SPI and in Gongzhuling c greater than the GDAI during than the GDAI shows that the the GDAI during drought 4 4.1.1. when

DAI DAI influence influence based on based on

month month - - month month - -

constructed constructed

(b) Gongzhuling city Gongzhuling (b) (b) Gongzhuling city Gongzhuling (b) . Firstly, for driving forces, the G . Firstly, for driving forces, the G

(b) The GDAI versus the SPI for 12 for SPI the versus The GDAI (b) (b) The GDAI versus the SPI for 12 for SPI the versus The GDAI (b) , though the SPI just considered the , though the SPI just considered the (Table 6) (Table 6)

(b) The GDAI versus the SPI for 12 for SPI the versus The GDAI (b) (b) The GDAI versus the SPI for 12 for SPI the versus The GDAI (b)

in Gongzhuling city from 1960 to 2010. in Gongzhuling city from 1960 to 2010.

16 16

6738 6737

month month - -

month month - - 1 1

r water cycle processes and elements, the GDAI is r water cycle processes and elements, the GDAI is

Figure 10. Compared the GDAI with the SPI from 1999 to 2001. Figure 10. Compared the GDAI with the SPI from 1999 to 2001. atural climate variability (NCV), anthropogenic climate change (ACC), underlying atural climate variability (NCV), anthropogenic climate change (ACC), underlying of n of n

Figure 8. Compared the GDAI with the SPI in Lishu country from 1960 to 2010. Figure 8. Compared the GDAI with the SPI in Lishu country from 1960 to 2010. Figure 9. Compared the GDAI with the SPI Figure 9. Compared the GDAI with the SPI . Secondly, fo . Secondly, fo (a) Lishu country Lishu (a) (a) Lishu country Lishu (a) CC CC influence influence (a) The GDAI versus the SPI for 1 for SPI the versus GDAI The (a) (a) The GDAI versus the SPI for 1 for SPI the versus GDAI The (a) and A (a) The GDAI versus the SPI for SPI the versus GDAI The (a) and A (a) The GDAI versus the SPI for SPI the versus GDAI The (a)

Compared the GDAI with the SPI in Gongzhuling city from 1960 to 2010. Compared the GDAI with the SPI in Lishu country from 1960 to 2010. NCV NCV The differences between the GDAI and the SPI are listed as follows The differences between the GDAI and the SPI are listed as follows of considered the conditions change (UCC), and hydraulic engineering regulation (HER) considered the conditions change (UCC), and hydraulic engineering regulation (HER) of

the DAI ut influence based on based on

vaporation equals to zero

month e GDAI during -

month -

The e . constructed constructed

month -

evaporation UCC and HER, especially not consider the impact of

erature is low in the winter. 2000. However, the results of

, did PDSI

water resources system, b . Firstly, for driving forces, the (b) Gongzhuling city Gongzhuling (b) . Firstly, for driving forces, the G (b) The SPI for 12 for The SPI (b) influence consider

(Table (Table 6)

. s not (b) The GDAI versus the SPI for 12 for SPI the versus The GDAI (b) , though the SPI just considered the

(Table 6)

(b) The GDAI versus the SPI for 12 for SPI the versus The GDAI (b)

for DRB which temp did s in June and July

k the same value. It

t PDSI

not consider the in Gongzhuling city from 1960 to 2010.

nsuitable

16 18 , evaporation, soil water, and runoff did

is u I 6740 6739

intensity of drought of the PDSI is more serious than the GDAI. CC

drought disaster record

recipitation

and A

assumption

month -

observed month the results simulated by the PDSI are generally greater than th - NCV

the r water cycle processes and elements, the GDAI is of

that

s month - Figure 10. Compared the GDAI with the SPI from 1999 to 2001. atural climate variability (NCV), anthropogenic climate change (ACC), underlying of the PDSI for the entire DRB

show close to . Secondly, for water cycle processes and elements, the s method which only considered temperature and assumed that

of n influence

Figure 8. Compared the GDAI with the SPI in Lishu country from 1960 to 2010. the PDSI the e Figure Spatial11. distribution of drought frequency simulated by the SPI in DRB. Figure 9. Compared the GDAI with the SPI and it considered the p Thirdly, for water resources system, the . Secondly, fo

(a) Lishu country Lishu (a) istribution igure 13 (a) The SPI for 1 for SPI The (a) F D CC versus influence water supply

Thornthwaite’ and (a) The GDAI versus the SPI for 1 for SPI the versus GDAI The (a)

and A (a) The GDAI versus the SPI for SPI the versus GDAI The (a) Spatial distribution of drought frequency simulated by the SPI in DRB. Compared the GDAI with the SPI from 1999 to 2001.

emporal T The GDAI GDAI The irrigation

NCV . .1. .1. The differences between the GDAI and the PDSI are listed as follows Figure 12 The differences between the GDAI and the SPI are listed as follows 2 he available moisture stored . atural water cycle n estimated by when temperature is lower than zero. This T different soil types. climatically appropriate for existing conditions. 4 4.2 drought period, especially in summer, that is, the The GDAI and the PDSI both can express two simulated drought by the GDAI are disaster PDSI just considered th the considered the conditions change (UCC), and hydraulic engineering regulation (HER) of

the PDSI the PDSI Figure 14 Figure 14 to evaluate to evaluate he climatic he climatic

the differences of the differences of

the methods of drought the methods of drought appropriate appropriate

and different underlying and different underlying

to 2001 to to 2001 to

. . Therefore, Therefore,

. .

rrigation area because rrigation area because , though , though (b) 1999 (b) (b) 1999 (b) (b) 1999 to 2001 1999 to (b) (b) 1999 to 2001 1999 to (b)

artificial water cycle artificial water cycle irrigation water supply irrigation water supply and at different times, Palmer assumed t and at different times, Palmer assumed t

they changed from 24 percent to 31 percent. they changed from 24 percent to 31 percent.

and

lly lly

19 19

hydraulic engineering regulation hydraulic engineering regulation

places places little; little; . 6742 6741 .

atural atural especia especia

of n of n

reservoir reservoir different different

not consider the impact of different soil types

did did

characteristic characteristic

t things at t things at Figure 12. Compared the GDAI with the PDSI in Lishu country. in Lishu PDSI the with GDAI the Compared 12. Figure Figure 12. Compared the GDAI with the PDSI in Lishu country. in Lishu PDSI the with GDAI the Compared 12. Figure Figure 13. Compared the GDAI with the PDSI in Gongzhuling city. in Gongzhuling PDSI the with GDAI the Compared 13. Figure Figure 13. Compared the GDAI with the PDSI in Gongzhuling city. in Gongzhuling PDSI the with GDAI the Compared 13. Figure of the GDAI are similar to the PDSI. Therefore, it is more of the GDAI are similar to the PDSI. Therefore, it is more the PDSI the PDSI , and chose weather data of western Kansas, central Iowa, and northwestern North , and chose weather data of western Kansas, central Iowa, and northwestern North

) ) four assessment units are four assessment units are - - 퐾 퐾

( (

(a) 1960 to 2010 to 1960 (a) (a) 1960 to 2010 to 1960 (a) (a) 1960 to 2010 to 1960 (a) (a) 1960 to 2010 to 1960 (a) istribution istribution correct index correct index coefficient coefficient D D

the results simulated by the PDSI are greater than the GDAI in Qintun i the results simulated by the PDSI are greater than the GDAI in Qintun i Compared the GDAI with the PDSI in Gongzhuling city. Compared the GDAI with the PDSI in Lishu country. patial patial not consider the regulation of Erlongshan not consider the regulation of Erlongshan

.2. .2. S .2. .2. S In order to compare differen The water resources shortage of the GDAI is expressed by water supply and water demand of water resources In order to compare differen The water resources shortage of the GDAI is expressed by water supply and water demand of water resources Dakota to correct. However, conditions, and the influence of human activities, drought frequency of sixty shows that did 4.2 characteristic system. The GDAI considered the levels and the drought events affected by human activities, especially Dakota to correct. However, conditions, and the influence of human activities, drought frequency of sixty shows that did 4.2 characteristic system. The GDAI considered the levels and the drought events affected by human activities, especially

Figure 13. Figure 12. 356 357 358 352 353 354 355 348 349 350 351 345 346 347 344 341 342 343 356 357 358 351 352 353 354 355 348 349 350 345 346 347 343 344 341 342

. efore,

of the

Ther .

efore, Because the water (Figure 17) .

at Gongzhuling city s rought frequency Ther

d .

not consider soil water

Because the water (Figure 17) .

at Gongzhuling city than the GDAI no matter s rought frequency

and d did

not consider soil water than the GDAI no matter

less and did

1999 to 2001 1999 to

in June and less

time, , and

1999 to 2001 1999 to

in June and

time, , and (b)

disaster record over 80 percent (b)

disaster record over 80 percent

long long

drought for a

gricultural system and ecosystem at Lishu country

gricultural system and ecosystem observed the entire DRB is at Lishu country

of groundwater resources

observed the entire DRB is 20

and

than the ated by the RWD are generally

6744 6743 important to a groundwater resources of

are

and

two drought disasters than the ated by the RWD are generally

important to a rought frequency

DRB is affected by drought

are express The d

that the results simul

can

urface water resources two drought disasters s

Figure 15. Compared the GDAI with the RWD in Lishu country. Lishu in RWD the with GDAI the Compared 15. Figure rought frequency DRB is affected by drought shows is greater.

6 he RWD the RWD the

T Figure 14. Spatial distribution of drought frequency simulated by the PDSI in DRB. . (a) 1960 to 2010 to 1960 (a) express The d

, however, soil water resources igure 1 F versus

that the results simul

can

urface water resources s and , but the simulated results are more severe Figure 15. Compared the GDAI with the RWD in Lishu country. Lishu in RWD the with GDAI the Compared 15. Figure

5 (Table (Table 6) Compared the GDAI with the RWD in Lishu country. Spatial distribution of drought frequency simulated by the PDSI in DRB. 2000

, shows is greater. four assessment units

annual or annual - - The GDAI GDAI The

6 . July Figure 1 he RWD 3 the RWD the .

T 4 inter in supply of the RWD considered resources results simulated by the RWD show that sixty Figure 14. Spatial distribution of drought frequency simulated by the PDSI in DRB. . (a) 1960 to 2010 to 1960 (a)

, however, soil water resources igure 1 Figure 15. Figure 14. 369 370 371 367 368 363 364 365 366 359 360 361 362 F versus and , but the simulated results are more severe

5 (Table (Table 6) 2000

, four assessment units annual or annual - - The GDAI GDAI The

. July Figure 1 3 . sixty resources results simulated by the RWD show that supply of the RWD considered inter in 4

371 369 370 368 367 366 365 364 363 362 361 360 359

for iver This study has

Dongliao r

This study has Dongliao

(b) 1999 to 2001 1999 to (b) (b) 1999 to 2001 1999 to (b)

on the northeast China, the

Temporal distribution of drought events and

The occurrences of drought events usually feature .

. from the perspective of water resources system

The occurrences of drought events usually feature

artificial water cycle should be followed. . - case study site

was studied a

21 from the perspective of water resources system

, s

6746 6745 artificial water cycle should be followed. - case study site

was studied a

, economic systems approach,

which is shortage of water resources, and with its development it transforms into

economic systems approach,

he basic principle of natural T Figure 16. Compared the GDAI with the inRWD Gongzhuling city. natural and socio drought assessment

Figure 17. Spatial distribution of drought frequency simulated by the RWD in DR RWD the by simulated frequency of drought distribution Spatial 17. Figure (a) 1960 to 2010 to 1960 (a) which is shortage of water resources, and with its development it transforms into

events.

which affects

trate this new he basic principle of natural the generalized drought assessment index (GDAI) drought T

Spatial distribution of drought frequency simulated by the RWD in DRB. Compared the GDAI with the RWD in Gongzhuling city. Figure 16. Compared the GDAI with the inRWD Gongzhuling city. natural and socio d which has high frequency of drought occurrence drought assessment

rminacy and randomness. Drought is firstly a resource issue demonsTo

. Conclusion asin Figure 17. Spatial distribution of drought frequency simulated by the RWD in DR RWD the by simulated frequency of drought distribution Spatial 17. Figure 5 a disaster issue dete propose assessing b (a) 1960 to 2010 to 1960 (a)

Figure 17. Figure 16. events. 381 382 383 384 377 378 379 380 375 376 372 373 374

which affects

trate this new the generalized drought assessment index (GDAI) drought

d which has high frequency of drought occurrence

rminacy and randomness. To demonsTo Drought is firstly a resource issue . Conclusion asin b assessing dete propose a disaster issue 5

384 383 382 381 380 379 378 377 376 375 374 372 373