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Handbook of Drought and Water Scarcity Principles of Drought and Water Scarcity Saeid Eslamian, Faezeh Eslamian

Meteorological Drought Indices: Definitions

Publication details https://www.routledgehandbooks.com/doi/10.1201/9781315404219-3 Nicolas R. Dalezios, Zoltan Dunkel, Saeid Eslamian Published online on: 12 Jul 2017

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The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The publisher shall not be liable for an loss, actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material. Downloaded By: 10.3.98.104 At: 20:03 30 Sep 2021; For: 9781315404219, chapter3, 10.1201/9781315404219-3 eral sectors of the economy, society, and environment [ economy, environment of the and society, sectors eral sev on impact significant having hazards major natural one of the as Moreover, considered is drought deficit. resources water with associated events climatic extreme as considered be can “nonevents” and as to referred also are droughts whyis This of time. period extended over an aregion in precipitation of lack or adeficiency from originate droughts Essentially, periodicity. atemporal phenomenon with regional anatural as considered is drought Indeed, variability. of nature’s climate part is Drought 3.1 of Technology University Isfahan Saeid Eslamian Society Meteorological Hungarian Zoltan Dunkel Athens of University Agricultural and Thessaly of University Dalezios Nicolas R. climatic conditions, the use of other indices should also be taken into consideration. into taken be also should indices of other use the conditions, climatic and regional on specific Based index. absolute and only the as but it may accepted not be versally, uni used to be Organization World by the recommended Meteorological is Index Precipitation Standardized The impacts. drought significant with along considered, also is droughts rological of meteo Moreover, assessment and presented. are monitoring indices drought used commonly the most Indeed, the world. around used being indices and indicators drought many are There indices. drought through features several explore and drought meteorological tounderstand taken under is An attempt indices. drought several through quantification its and drought rological meteo covers chapter This to region. from region variable highly are of precipitation deficiencies in that result conditions the atmospheric since event, natural aregion-specific being drought cal meteorologi as to referred are deficiencies precipitation accumulated of stages early The event. climatic extreme an as regarded be can and of time over a period a region in events of precipitation lack by the caused basically is Drought economy, environment. of the and society, sectors several on impact significant having hazards major natural one of the as considered is Drought scale. Abstract  Introduction

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]. With the exception of meteorological drought, the other types of drought, such as agricul as such of drought, types other the drought, of meteorological exception the ]. With Drought typ Drought [ 46

Time (duration) ]. Economic impact If drought is considered as a phenomenon, it is certainly an atmospheric phenome atmospheric an a phenomenon, as certainly it considered is is drought If Re (amoun Nat. Hazards Earth Earth Hazards Nat. al., et N.R. (From Dalezios, procedure. sequential temporal and es Pr duce gr de ec Reduc oundwater re ep pe re ipitation deficiency d infiltration,ru ser t, intensit re voirs, lake voirs, ed rcol wildlife habitat duc s streamf Natural climate ation, and ed 36 y, S charge wetland timing) oil waterdeficienc ]. A continuation of these dry conditions over a longer period of over alonger period conditions dry of these ]. Acontinuation Soci s, low, inf andpond noff al impact s, , low to varia High temp.,highwind s; Pl sunshine, lesscloudcover sE re ant waterstres Incre la bility bioma tive humidity, gr y and transpiration Handbook of Drought and Water and Scarcity of Drought Handbook nv ased ironmental impact ss andyiel ev ­ precipita ap s, Figure 3.1 Figure oration re duc d ea s, te low ed tion regimes. Meteorological Meteorological regimes. tion r ). Meteorological droughts droughts ). Meteorological s

Hydrological Agricultural Meteorological drought drought drought 52 ]. ]. - - - - Downloaded By: 10.3.98.104 At: 20:03 30 Sep 2021; For: 9781315404219, chapter3, 10.1201/9781315404219-3 the development of a global drought risk model are also discussed. also are model risk drought development of aglobal the for need the and universally applied tobe (SPI) Index recommendation and Precipitation Standardized the of adoption The presented. is indices drought meteorological of indicative A description appear. sloware to often drought of impacts the Indeed, effort. acontinuous requires of warnings, semination dis as well as methods, warning early and Moreover, prediction ered. improvement of drought the - consid also is assessment and monitoring Drought of indices. use the through presented is drought meteorological of quantification Then, characteristics. and features its with along drought, rological meteo of description is bya followed This is attempted. types and definitions, concepts, of drought of drought. types other one of the to event leading amultiseasonal into develop may also of drought However, types these small. relatively Indices Drought Meteorological evident that there is no precise and universally accepted definition of drought [ drought of definition accepted universally and no precise is there that evident become has it consideration, thorough and way. ahomogeneous in considered However,detailed a after and addressed be may drought that seems it guess, afirst As concept. acompound constitutes Drought 3.2.1 effectiveness. numerical and implementation, joint potential interrelations, limitations, advantages, practical and theoretical their comparing and assessing and indices drought used widely and well-accepted several analyzing of trend consists current The investigation. and operational scientific greatest the ter, deserves drought charac peculiar toits Due circumstances. natural due tounfavorable loss annual toaregional cantly - signifi contribute also can which frost, or hailstorm, flood, as such hazards, environmental other with task. acomplicated is period end of adrought the and onset of the Moreover,or months. assessment the weeks by deficits precipitation slow lagging to appear, also are effects drought nature, creeping due toits Similarly, apparent. become impacts before the months or may take quickly may happen ciency, which - defi precipitation cumulative the is factor driving phenomenon. The acreeping as known also hazard, environmental aslow-onset is drought mentioned, already As hazards. atmospheric among predictable least probably the event and long-lasting and slowlydeveloping most the possibly is drought events, cal meteorologi extreme the Among ways. several in hazards environmental from other differs Drought 3.2 many different assessments and considerations of drought, because impacts may differ significantly. differ may impacts because drought, of considerations and assessments different many are there sectors, within Even sectors. between vary impacts drought since specific, application to be need also definitions addition, In of drought. character regional the toidentify factors important be also may humidity relative and wind, temperature, consideration, precipitation Moreover, besides regions. between significantly may differ of precipitation form and seasonality, amount, the example, an As tics. characteris climatic specific maintains region each and extent in are regional droughts fact, In specific. [ severity of degree and its drought of a existence the about confusion the to contribute simply which of definitions, dreds severe than those of a drought. From the definitions mentioned earlier, it is evident that dealing with with dealing that evident is earlier, it mentioned definitions From the of a drought. those than severe less conditions to confined be should term of this use weather, the where dry of abnormally period presented: also is spell” “dry of Moreover, definition regions. for the low latitude used mainly is term the where of rainfall, (almost) complete absence by the characterized year of the period included: is season” “dry of definition the source, same From the imbalance. hydrological aserious tocause precipitation of lack the prolonged for sufficiently weather dry (2) and of precipitation of abnormally ciency period defi (1)are provided: marked or prolongedabsence drought of definitions simple very two sources, This chapter covers the subject of meteorological drought indices. A comprehensive presentation comprehensive A presentation indices. drought of meteorological thesubject covers chapter This It is recognized that because of these mainly temporal characteristics, drought cannot be compared compared be cannot drought characteristics, temporal mainly of these because that It recognized is Starting with the International Meteorological Vocabulary [ Vocabulary Meteorological International the with Starting  Drought Concepts  Drought Definitions and Types and Definitions Drought 45 ]. Needless to say, definitions of drought should be region and application or impact impact or and application be region should drought of tosay,]. definitions Needless 50 ], which is one of the most authentic authentic most one is of the ], which 16 ]. Indeed, there are hun are there ]. Indeed, 29 ------Downloaded By: 10.3.98.104 At: 20:03 30 Sep 2021; For: 9781315404219, chapter3, 10.1201/9781315404219-3 meteorological or climatological, agricultural, hydrological, and socioeconomic drought [ drought socioeconomic and hydrological, agricultural, climatological, or meteorological namely,before, mentioned been already have which categories, into four types and definitions drought groups Society Meteorological American the Specifically, complex. is drought of types different the the world. throughout acceptable be could which drought, of definition adequate to find a completely difficult is Therefore, it perspective. economic and historical their or interest cific spe their either on depending society, the groups of various to meanings different has drought Indeed, view. of points different of from a number identified may be adrought and task not asimple is drought 30 drought and constitutes an attempt to quantify a drought and its magnitude. It is also important tonote important It also is magnitude. its and adrought toquantify attempt an constitutes and drought to related information “value-added” of deriving amethod is index an Indeed, index. ment of a drought develop the into synthesized be can of them several where indicators, to drought lead aggregation and interpretation, analysis, Data deficiency. or stress drought-related potential of indication an provide and of drought, features describe which variables, of climate measures are indicators Drought indices. and/or indicators of use the through implemented be can assessment and quantification Drought 3.2.2 earlier follows. earlier mentioned types drought of the description abrief drought, meteorological is chapter of this subject the that mind in Keeping drought. physiological and namely, atmospheric added, are types drought the clouds, and by a lack of rain-producing clouds. of rain-producing by alack and clouds, the of continentality the in day, per increase by an of rainfall amount the in decrease by a substantial ized [ normal than and morestable drier significantly atmosphere the keeping level, high the in subsidence favors and anomaly pressure middle-level the produces which lower atmosphere, the in anomalies ture tempera positive in cloud cover results reduced Moreover, atmosphere. corresponding the the in level middle at the systems of high-pressure or centers of ridges persistence the with associated tobe shown are droughts general, in that, stated be It category. can spell dry tothe refers more or less type drought average yields in both pastoral and grain-producing regions. grain-producing and pastoral both in yields average below- to leads This stage. growth acritical during community by aplant required below that soil—falls the in stored water and precipitation availability—from water plant when occurs drought Agricultural shortage. of water because average the than less considerably is yield onethat is second the and equate tion amounts, which corresponds to the general definition of drought. of definition general tothe corresponds which amounts, tion caused by abnormally cold weather or in the case when the plant is infected. is plant the when case the or in weather cold by abnormally caused be could situation This conditions. atmospheric prevailing on the based assessment no drought is there but symptoms, drought shows when plant circumstances the to refers situation This moisture. able soil mally occurs on a rather large area, such as awatershed. as such area, large on arather occurs mally nor drought groundwater. andHydrological storage, reservoir streamflow, as such of factors, bination be close to the definition of famine. of definition tothe close be can definition its conditions, Under specific drought. and/or agricultural hydrological, meteorological, due to goods of economic some lack the mean It may also spells. dry repeating of consecutively impact disadvantageous It any may imply categories. drought of several integration the as considered be can one [ profitis only of which indicators, economic and social by both sured 7 , 34 For a better understanding, drought is classified into several types; however, the relationship between between however,the relationship types; intoseveral classified is drought understanding, For abetter Atmospheric drought Atmospheric Meteorological drought Meteorological Hydrological drought Agricultural drought Agricultural Socioeconomic drought Socioeconomic Physiological droughtPhysiological ]. Studies in several areas around the world have shown that drought periods are often character often are periods drought world that have shown the around areas several in ]. Studies  Drought Quantification and Monitoring and Quantification Drought receives two explanations: the first one is that the available soil moisture is inad is moisture soil the available that is one first the explanations: two receives occurs if too high a saturation deficit has been measured for a durable time. This This time. for a durable measured been has deficit asaturation high too if occurs is generally defined as a period of below normal conditions for onecom conditions or a below of normal period as a defined generally is can occur when the plant is unable to take up water in spite of sufficiently avail spite of sufficiently in up water to take unable is plant the when occur can is defined in terms of loss from an average or expected return. It can be mea can It return. expected or an average from of loss terms in defined is means a longer period of time with considerably less than average precipita average than less considerably with of time alonger period means Handbook of Drought and Water and Scarcity of Drought Handbook 27 ]. Socioeconomic drought drought ]. Socioeconomic 24 ]. Two more ------Downloaded By: 10.3.98.104 At: 20:03 30 Sep 2021; For: 9781315404219, chapter3, 10.1201/9781315404219-3 tence and severity of drought. severity and tence exis the to verify indicators consider to multiple best is it summary, In scales. at different drought of characteristics and distribution temporal and spatial of the detection for tool the important an become gradually has remote sensing that recognized it is Nevertheless, data. sensed remotely with case the usually is this and recordlength, may not have asufficient indicators some that is problematic usually is What severity. drought of and monitoring assessment the in significant also are indicators other many indicators, drought of many basis the is precipitation Even though region. for any tion period(s) of precipita the “crucial” determine to important is it Thus, of adrought. beginning of the indication an not necessarily is time this during of precipitation ashortage then seasonal, typically time [ real near in to obtain difficult importantly, most and, inaccurate often aregion, in limited usually are which data, on rely rainfall monitoring and assessment of drought methods Traditional of precipitation. long-term records and have reliable approach. ablack-box is modeling this although models, (ARIMA) average moving integrated autoregressive as such forecasting, for drought used be could values index drought of analysis series time Alternatively, models. circulation global through prediction or climate casting fore weather on either based be could future the into value index drought of the prediction Indeed, ways. several in considered be of can DEWS, use or the prediction, and forecasting drought Indeed, sectors. for many consequences more toeven severe may lead impacts drought preparedness, and ning inputs in any drought preparedness and mitigation plan [ plan mitigation and preparedness drought any in inputs significant prove and tooffer very regions sensitive environmentally and economically in importance [ preparation drought for adequate part important an constitute and conditions drought on monitoring (DEWS) focalize systems warning early Drought order tomonitor droughts. in region of the matology - cli drought and climate the both understand to needed step first important an is of a region teristics charac climate and weather the primary about information Gathering and monitoring. identification drought toquantify available are indicators what and develop how droughts toknow necessary it is conditions. geographic [ judgment personal and experience by professional affected ultimately is determination their as justified, cisely be to pre difficult are criteria, evaluation the of importance the relative reflect basically which weights, criteria The complication. excessive without indices of drought evaluation for the framework reasonable a provide earlier mentioned criteria the but condensed, or expanded be may criteria of list The sionality. dimen and expandability, sophistication, transparency, tractability, robustness, namely, possess, ally ide should index an that properties desirable on arebased criteria These index. each into constructed is sectors. tovarious applied be or can applications multiple in used to be potential have the indices drought Many used. tobe likely are they which in applications various at the tolook best it is indices, drought various selecting and evaluating In zone. climatic acertain problem in a particular to address developed have been many since locations, all in applied be can indices not all that assessed been it has developed, been have also indices drought other As severity. sion of drought expres an constitute can that or value of anumber derivation on the development emphasizes indices [ data satellite and conventional on both based ment, and monitoring. There are several review studies on the use of drought indices [ indices drought of use the on studies review several are There monitoring. and ment, [ of drought characteristics statistical and togeophysical related is value index how an and index the in weighted and combined is indicator how each is, that index, of an validity operational and scientific the about required always are Clarifications well. as indicators are indices that Meteorological Drought Indices Drought Meteorological 47 With the basic characteristics of drought involving a lack or deficit of precipitation, it is critical to critical is it of orprecipitation, deficit alack involving of drought characteristics basic the With Drought monitoring is an equally important issue. Given the complexity of drought phenomenon, of drought complexity the Given issue. important equally an is monitoring Drought values assigned and criteria decision of weighted aset indices, of drought utility overall the judging In Drought indices can be easily implemented and are extensively used in drought quantification, assess quantification, drought in used extensively are and implemented easily be can indices Drought , 48 , 51 ]. Nevertheless, DEWS for the monitoring of drought evolution and development is of critical development of critical is and evolution of drought monitoring DEWS for the ]. Nevertheless, 24 ]. Nevertheless, the weights can be adjusted to comply with local or regional climatic or climatic or regional local tocomply with adjusted be can weights the ]. Nevertheless, 8 , 9 , 27 40 ]. It should be noted that the progression of drought of drought progression the ]. that noted be It should ]. If the precipitation distribution for a region is is for a region distribution precipitation ]. the If 7 ]. Needless to say, without adequate plan tosay, adequate ]. without Needless 38 ]. 3 , 10–13 , 17 , 22 , 28 , 31 31 ------] Downloaded By: 10.3.98.104 At: 20:03 30 Sep 2021; For: 9781315404219, chapter3, 10.1201/9781315404219-3 of the event. the of the duration and severity, deficiency, its of precipitation onset of the timing tothe related closely is impacts of drought Moreover, magnitude subject. the technical acomplicated is end time and of start acomplex assessment phenomenon, is the drought Since or years. for months continue can and lished estab of tobecome 2–3 months aminimum require usually Droughts months. in usually expressed temporal variability of several drought features in quantitative terms [ terms quantitative in features drought of several variability temporal and spatial the todelineate used be can methods and data and/or remote sensing conventional Indeed, end time. and onset, extent, areal periodicity, duration, severity, as such features, drought several todetect necessary it is impact, their toalleviate and hazards monitor drought and order toassess In 3.2.3 32 some key features follows. features key some normal conditions. normal or toaverage toreturn required are levels groundwater and reservoirs whether consider also should one Similarly, terminated. tobe drought for the sustained tobe precipitation of normal period time required the is what and precipitation tonormal by areturn signaled is end todrought an whether ered Moreover, made. be consid be should it should determinations these criteria on what and of a drought time the end and onset the determine to difficult It usually is or indices. of indicators values threshold end time hand, other the On value. threshold certain reaching or indices indicators through assessed is of adrought beginning curves for several sites throughout a region [ aregion throughout sites for several curves by severity–duration–frequency presented usually be can droughts, as such events, for extreme data and duration, particular in a occurring depth the total given by eventis extreme an of magnitude The once. exceeded or eventis reached the of magnitude the which within time of interval the average as defined may be which interval, or recurrence period return by its expressed usually is drought, as such event, immediately clear. immediately not is index of aspecific supremacy the category, individual an Even within severity. drought tify toquan technique unifying not asingle is There severity. of maximum area the center, is which epi so-called of the shift annual and aseasonal is there and gradually, evolve drought by severe affected regions The of impact. determination the in toduration linked closely is and normal from (PDSI), Index Severity Drought Palmer as such or index, level; reservoir as indicator, such tion; precipita as such parameter, of climatic some departure by the measured is severity the Indeed, earlier. mentioned classes the include which indices, and indicators drought through determined usually is severity The extreme. and severe, moderate, mild, as such phenomenon classes, into the of escalation as defined is of drought severity The shortfall. the with associated of impact severity planning. use land affect and tourism, and recreation health, energy, transportation, omy, agriculture, as such econ of the sectors for several implications may have serious of drought characteristics spatial the Nevertheless, region. theentire toaffect however, year; not it expected is every of drought occurrence the justify States, United the as such regions, of large size and diversity Moreover,year. climatic the to from year and season to season from shifting time, with varies and gradually evolves droughts severe of extent areal the that be mentioned should It characteristics. spatial their by differ also droughts that It recognized is class. each in of pixels number the by counting parameter of this tion delinea the in significantly contributed has sensing Remote or indices. by indicators classes severity Onset Duration Severity Areal extent Areal Periodicity  Drought Features and Characteristics and Features Drought or the beginning of a drought is determined by the occurrence of a drought episode. The episode. of adrought occurrence by the determined is of adrought beginning or the or intensity of drought refers to the degree of the precipitation shortfall and/or the and/or the shortfall precipitation of the degree tothe refers of drought or intensity of a drought episode is defined as the time interval from the start to the end time time theend to start the from interval time the as defined is episode of adrought is considered the recurrence interval of drought. Indeed, the frequency of an extreme extreme of an frequency the Indeed, of drought. interval recurrence the considered is of drought is considered the spatial coverage of the phenomenon, as is quantified in quantified phenomenon, is of as the coverage spatial the considered is of drought of a drought episode signifies the termination of drought based again on again based drought of termination the signifies episode of adrought 6 ]. Handbook of Drought and Water and Scarcity of Drought Handbook 8 , 9 , 24 ]. A brief description of ]. description Abrief ------Downloaded By: 10.3.98.104 At: 20:03 30 Sep 2021; For: 9781315404219, chapter3, 10.1201/9781315404219-3 current presentation is restricted to meteorological drought indices. drought meteorological to restricted is presentation current the drought, of types all from indices to refers classification this Although information. sensed remotely on based indices and indices, or recursive combined indices, moisture soil indices, aridity anomaly, and using similarity characteristics [ characteristics similarity using and features. drought several of detection sensed or remotely efforts for modeling information truthing ground- as used be also can index drought a meteorological Furthermore, end time. and duration, tude, magni severity, onset, as such features, of drought for anumber of thresholds assessment the involve (SPEI). Index Evapotranspiration Precipitation Standardized SPI,and PDSI, deciles, rainfall namely, ces, indi used widely and of indicative afew adescription with along indices, drought meteorological available value. numerical prehensive intocom a indicators environmental or other streamflow, snowpack, vegetation, moisture, soil as such parameters, other and on rainfall data by assimilating over aregion of drought severity the assess and to quantify attempt an constitute Moreover, indices to region. region from drought variable highly are deficiencies, precipitation in resulting causes multiple through develop and prevail which conditions, the atmospheric since event, natural aregion-specific as considered be must drought meteorological mentioned, already As indices. drought of meteorological subject the covers chapter this Nevertheless, another. is index ocean and index of climate one is type index adrought that known It well is 3.3 Indices Drought Meteorological drought indices follows. indices drought of meteorological classes the of description A brief reference. corresponding the with classes different in [ decision-making near-real-time for monitoring of drought case the in especially data, raw than more useful far considered essentially is [ decision-making for drought on tion informa timely order of toprovide DEWS in context the in used be can indices drought Meteorological 3.3.2 sectors. hydrological and/or the agricultural the toimpact long enough vails pre then which drought, of meteorological onset the with starts drought, or hydrological agricultural as such of drought, type other of any beginning the Nevertheless, conditions. climatic existing to the according locally tovary expected are respectively, 6months, and of normal 80% for example, duration, corresponding the and deficiency of thresholds selected The considered. usually is of time period mined someover predeter deficiency of precipitation threshold a drought, of meteorological identification [ period dry of the duration by the and amount or average “normal” tosome compared as deficiency by precipitation specified dryness of degree the as defined usually is drought Meteorological 3.3.1 be related to average amounts on a monthly, seasonal, or annual basis. or annual on amonthly, seasonal, amounts toaverage related be may normal from deviations precipitation actual Moreover, for example, for regions, monsoon alistic. unre seems earlier mentioned consideration the patterns, rainfall by seasonal characterized for regions hand, the other On threshold. specified some lower precipitation than with of days number on the based of drought periods identify and may consider drought meteorological climates, subtropical or humid tropical as such regimes, precipitation by year-round characterized for regions Specifically, zones. matic Table 3.1 Table A classification and grouping of drought indices is considered based on recently conducted studies studies conducted on recently based considered is indices drought grouping of and A classification of list as a as well indices, drought and drought of meteorological review a brief presents section This As expected, there are different characteristics of meteorological drought for different regional cli regional different for drought of meteorological characteristics different are there expected, As   Meteorological Drought and Indices and Drought Meteorological  Meteorological Drought Meteorological Classification of Meteorological Drought Indices Drought of Meteorological Classification presents an indicative list of available and commonly used meteorological drought indices indices drought meteorological used commonly and of available list indicative an presents 36 ]. Moreover, several other uses of a meteorological drought index index drought of ameteorological uses ]. other Moreover, several 12 13 ], namely, atmospheric drought indices, indices of precipitation precipitation of indices indices, drought atmospheric ], namely, ]. It should be stated that a meteorological drought index value value index drought ameteorological that ]. stated be It should 44 ]. For the 33 ------Downloaded By: 10.3.98.104 At: 20:03 30 Sep 2021; For: 9781315404219, chapter3, 10.1201/9781315404219-3 34 drought index takes the simple form of a typical meteorological element, namely, the saturation deficit [ deficit saturation namely, element, the meteorological of atypical form simple the takes index drought meteorological corresponding The irrigation. foruse water effective in mainly them introducing worth it is [ indices accepted are commonly not indices These species. of certain case the in strophic cata be could days of these consequence but the days, afew only sometimes amonth, than much shorter usually is of analysis type for this scale temporal the although drought, of atmospheric characterization the standar The 3.3.2.1  Indices of Atmospheric Drought Atmospheric of Indices d signal for a dry spell is low humidity. The water vapor saturation deficit is commonly used for used for commonly is deficit saturation vapor water The low is humidity. spell for adry d signal Remotely sensed information sensed 5. Remotely indices 4. Recursive . Precipitation anomaly indices anomaly Precipitation 2. 1. Atmospheric drought indices Classification of Drought Indices Aridity indices 3. Aridity TABLE 3.1 5.4 Stress degree days 5.3 Normalized difference vegetation index (NDVI) 5.2 Vegetation index 5.1 Crop water stress index (CWSI) 4.11 Reconnaissance drought index (RDI) 4.10 Effective drought index 4.9 Keetch–Byram drought index (KBDI) 4.8 Palmer crop moisture index (CMI) 4.7 Palmer drought index (PDI) 4.6 Reclamation drought index (RDI) 4.5 Surface water supply index (SWSI) 4.4 Standardized precipitation index 4.3 Palmer drought index (PDSI) severity family 4.2 Bhalme–Mooley drought index (BMDI) 4.1 Fooley anomaly index (FAI) 3.11 Bowen ratio 3.10 balance Surface energy 3.9 Relative evaporation 3.8 Aridity index: moisture available index 3.7 Potential evaporation ratio 3.6 Potential water deficit 3.5 Thornthwaite index 3.4 Selyaninov’s hydrothermal coefficient 3.3 Ped’s drought index (PDI1) Martone3.2 De aridity index 2.5 Average standard anomaly 2.4 Standardized anomaly index (SAI) 2.3 Relative anomaly 2.2 Relative precipitation sum 3.1 Lang’s index rainfall 2.1 Precipitation index 1.1 Saturation deficit

Indicative Li st of and Classes Indices of Meteorological Drought Handbook of Drought and Water and Scarcity of Drought Handbook References [18 [43 [19 [43 [26] [29] [2] [14 [37 [41] [33 [30 [45 [49 [50 [33 [5]

,31 ,20 ] ] ] ] ] ] ] ] ] ] ] ] 33 ], but sometimes ], but sometimes 50 ]. - Downloaded By: 10.3.98.104 At: 20:03 30 Sep 2021; For: 9781315404219, chapter3, 10.1201/9781315404219-3 are several existing precipitation anomaly indices ( indices anomaly precipitation existing several are There value. threshold of any establishment before the data yield and index drought between parisons long-term have com tobe there Indeed, performance. better for possibly of deviation generalization or or normalization, somecombinations, certainly are There value. precipitation or average a normal from deviation the is index drought simplest the Therefore, period. or season rainy abnormal an after occurs usually drought that understood it is Nevertheless, toyears. 3or 4weeks from last could of time 3.3.2.2 record; the second is between the lowest 10% and 20% and the fifth decile would be the median. the be would decile fifth the and 20% lowest 10% and the between is second the record; ina values all precipitation the 10%lowest of by value exceeded not the precipitation is decile The first deciles).or distribution of (tenths into parts 10 split then is distribution The or deciles. 10 quantiles, into divided may be marker below this and above observations Climatological record. of the tendency central the assess to the mean of instead used is The median distribution. frequency acumulative struct con to to lowest highest from ranked first along-term recordare from totals precipitation monthly [ suggested been has drought meteorological for monitoring system decile–based A rainfall 3.3.3.1 PDSI, SPEI. SPI, and deciles, namely, rainfall presented, are indices From 3.3.3 o forms Any Meteorological Drought Indices Drought Meteorological tion. The theoretical base for the aridity index is the evapotranspiration/precipitation ratio [ ratio evapotranspiration/precipitation the is index aridity the for base theoretical The tion. vegeta tomaintain inadequacy toprecipitation related is which of climate, acharacteristic is Aridity 3.3.2.3 tion. There are several types of aridity indices ( indices aridity of types several are There tion. evapotranspira the of the approximation in is indices aridity the in difference the since degree-days, or on temperature only based evapotranspiration toestimate models empirical touse is approach plest 3.3.2.4 of PDSI ( family the including indices recursive several are There of computation. method due totheir indices recursive called are indices These variables. meteorological corresponding the of values previous on depend values of memory, actual where akind possess which spell, or dry droughts determined cally of meteorologi delineation the in utility have high provenbe of to indices These basis. on amonthly deficits of prolonged moisture effect cumulative the express and describe to attempt indices These temperature data platforms at a global scale. global a at platforms data temperature and of precipitation availability due tothe years forthcoming the in drastically toincrease expected is indices drought of sensed remotely Moreover, utility the or methods. algorithms by sensed remotely computed are and index the in used are and/or temperature precipitation that provided index sensed toaremotely converted be can index drought meteorological any that stated be it can rule, a general As and methods. data on reliability increasing with advances andtechnological due toscientific ing sens the field ofremote in anddevelopment progress significant been has there years, recent in that mentioning chapter. It worth is of this scope the outside are indices drought agricultural Nevertheless, indices. vegetation as known drought, of agricultural indices as used mainly are thus, and, of vegetation indices drought remotely sensed used widely and existing ofMost the 3.3.2.5 Table 3.1 Table       Description of Selected Meteorological Drought Indices Drought Meteorological ofSelected Description Rainfall De Rainfall Recursive Dr Recursive Indices of Precipitation Anomaly Precipitation of Indices Aridity Indic Aridity Indices Based o Based Indices Table 3.1 Table f drought indices are related to some antecedent precipitation amounts. This past period period past This amounts. precipitation toantecedent some related are indices f drought , and for illustrative purposes, a few commonly and widely used meteorological drought drought meteorological used widely and commonly a few purposes, for illustrative , and ). ciles ought Indices ought es n Remotely Sensed Parameters Sensed n Remotely Table 3.1 Table Table 3.1 Table ). ). are based on spectral reflectance reflectance on spectral based are 5 ]. sim The 15 ], where 35 ------Downloaded By: 10.3.98.104 At: 20:03 30 Sep 2021; For: 9781315404219, chapter3, 10.1201/9781315404219-3 where decile for all such months, then the meteorological drought may be considered to have ended [ tohave ended considered may be drought meteorological the then months, such for all decile first the exceeds total this If of adrought. beginning the since precipitation, total Meteorology, considers of Bureau Australian of the Watch Drought byService the used is which rule, third A supplemental, criteria. stopping two upon the relying when deciles torainfall suited may well not be precipitation sonal sea highly with climates Therefore, deficit. water the not terminate does and trivial is of precipitation absolute thequantity though even rule, stopping first the activate can months, summer dry as such tine, rou is or no precipitation little which in periods during of precipitation amounts But minor conditions. toor normal above close is rainfall observed when toterminate for adrought reasonable it is example, For difficulties. toconceptual lead can PDSI. However, simplicity as such this comprehensive indices, more than fewer assumptions and data precipitation only requires and to calculate simple DI is relatively Decile indices (DIs) are grouped into five classes, two deciles per class, which are shown in shown are which class, per twodeciles classes, (DIs) five into grouped indices are Decile approach. for this record(30–50 required long years) is precipitation Areasonably deciles. of these terms 36 3.3.3.2 droughts. hydrological and agricultural tomonitor both applied been it has as of drought, types tomonitor all used be can method deciles the the region, of climate the on based thresholds establishing of flexibility the With used. being thresholds the by defining region, the in of drought characteristics and data to the according ends, and begins adrought when of aDEWS establishes part as method deciles rainfall the Having of response. type some trigger which thresholds, as used be must deciles certain method, of this implementation For the historically. compares regime precipitation current the where exactly toknow researchers allowing or region, for a location dryness of the status the determines automatically nature forward β parameters, distribution gamma of the estimation likelihood of maximum aprocess through ducted [ preferred (or and years more) more optimal 50–60 being with needed are values complete monthly serially [ historically months same tothe relative periods, 12-month The SPI [ and γ and P is the variable the x is This method is simple but needs a long-term period of record to have the most utility. The straight The utility. the most haveof to record period a long-term is simple but needs method This Any precipitation value (e.g., from the current or past month) can be compared with and interpreted in in interpreted and with compared be month) can or past current (e.g., the from value precipitation Any ( x ) is th ) is (  Equation 3.1 Equation SPI 26 16 e probability density frequency (p.d.f.) equation frequency density e probability ] quant ]. The historical rainfall data of the station are fitted to a gamma distribution. This is con is This distribution. gamma toa are fitted station the of data rainfall historical ]. The ifies the precipitation deficit for multiple time scales, such as for 3-, 6-, 9-, asand for 3-, 6-, such 9-, scales, time multiple fordeficit the precipitation ifies ): Melbourne, Victoria, Australia, 1967. drought indicators, No. Bulletin Bureau 48, of Much Meteorology, above normal 9–10: HighestDeciles of 20% data 7–8:NextDeciles of highest 20% data Much below normal of 5–6:Middle 20% dataDeciles 3–4:NextDeciles lowest of 20% data 1–2:Lowest ofDeciles 20% data Level Decile TABLE 3.2 Source:

Gibbs, W.J. and Ma

P The Rainfall Deciles C Deciles Rainfall The () x xx -g 1 ex bg g p/ G () () - her, J.V., as deciles Rainfall b Handbook of Drought and Water and Scarcity of Drought Handbook lassification Table Above normal Above Near normal normal Below g > Moisture Level 25 0

, 38 ]. Ideally, at least 20–30 years of years 20–30 ]. at least Ideally, 24 Table 3.2 Table ]. (3.1) - - - - . Downloaded By: 10.3.98.104 At: 20:03 30 Sep 2021; For: 9781315404219, chapter3, 10.1201/9781315404219-3 an equivalent index, namely, the Reconnaissance Drought Index [ Index Drought Reconnaissance namely, the index, equivalent an [ SPEI the respectively, are, indices of such examples Typical of aregion. balance water the impacting are tures is based on the model for calculating PET [ for calculating model on the based is which computation, balance simple water a uses thePDSI, like The SPEI, balance. water a simplified PET. and precipitation between i Drought 3.3.3.3 3.3 Table in of shown SPI are classes Seven variable. are impacts and scales time where droughts, hydrological and agricultural but also meteorological not only monitoring in useful the bevery allowed SPI to has flexibility This or less. months of 24 for periods used mostly it is but from 1to 72 months, periods for calculated been the SPIhas Initially, steps. time different selecting by periods and long-term short- both for calculated be can and SPI flexible is the Nevertheless, data. missing with calculated be can index the that SPI’s is for the reason appeal Another conditions. wet and dry both for PDSI,monitoring SPI used tothe may be Similar “magnitude.” drought’s the termed be can event drought a within the months all the SPI forof sum positive The event continues. the that month each for intensity and andend beginning by its defined aduration has therefore, event, drought Each utility. amount of great has a the SPI where is This positive. the SPIbecomes when event The ends less. transpiration values. Having the same flexibility that the SPI has in being able to be updated weekly weekly be ableupdated to being in the SPIhas that flexibility same the Having values. transpiration evapo actual for determining requirements data additional the given usable, and simple calculations the keeps also This required. is balance water of the estimation ageneral only since not arequirement, is this indices but for drought parameters, meteorological several using obtained be of PET can estimates good that have shown studies Several summers. warm and for dry mainly for PET,used valid is which SPI ( SPI where Meteorological Drought Indices Drought Meteorological

tation and its long-term seasonal mean by the standard deviation ( deviation standard by the mean long-term seasonal its and tation The SPEI is essentially based on the SPI and adds a temperature component computation of the for temperature a andadds the SPI on based essentially is The SPEI of −1.0 intensity or an reaches and negative SPI continuously is the anytime event occurs A drought deviation standard its σ is McKee [ McKee X X im ij Table 3.3 Table is the seasonal precipitation at the i at the precipitation seasonal the is is the long-term seasonal mean long-term seasonal the is 43  ], which uses the difference between precipitation and potential evapotranspiration (PET), and (PET), evapotranspiration potential and precipitation between difference the uses ], which SPEI ndices that also account for temperatures can help put into proper perspective how tempera help put proper perspective into can for temperatures account also that ndices 26 ). The SPI is computed by dividing the difference between the normalized seasonal precipi seasonal the normalized between difference the ).dividing computed The SPIis by ] used a classification system to define drought severities (intensities) resulting from the from (intensities)resulting severities drought define to system aclassification ] used −2.0 and less −1.5 to −1.99 −1.0 to −1.49 to 0.99 −0.99 +1.0 to 1.49 +1.5 to 1.99 +2.0 and greater Standardized Precipitation Index Value TABLE 3.3 Source:

Guttman, N.B., J

Standardized P th rain gauge station and j and station gauge rain th 40 SP . Am. Water Resour. Assoc., 35(2), 311, 1999. ]. Alternatively, the Blaney–Criddle [ Blaney–Criddle the ]. Alternatively, I recipitation Index ClassificationScale = XX jim ij - s

Equation 3.2 Equation th observation th 8 . Extremely dry Severely dry Moderately dry Near normal Moderately wet Very wet Extremely wet Moisture Level , 9 , 42 ], which is based on the ratio ratio on the based is ], which ). Thus, ). 4 ] method could be be could ] method (3.2) 37 - - - Downloaded By: 10.3.98.104 At: 20:03 30 Sep 2021; For: 9781315404219, chapter3, 10.1201/9781315404219-3 3.3.3.4 drought. agricultural track tobetter potential the it has such, As calculations. balance water includes the methodology since droughts, of types different the monitoring in utilized tobe capacity the the SPEI, has it of nature flexible the Given period. or awet dry todetermine precipitation for PET and calculations basic the between difference the SPEI uses the step, time for each window amoving using 38 potential to identify meteorological and agricultural drought episodes [ episodes drought agricultural and meteorological toidentify potential additional the with perspective, aregional into balance water full toput the attempt an considered is One of the mos ofOne the into the range of +4 to −4 ( to−4 of +4 range the into falling values most with scheme, categorization dry and awet both PDSI SPI, has the the Like regions. different the between PDSI of comparisons direct facilitate to periods time and regions for different of PDSI [ follows [ estimation transpiration on evapo based demand supply and moisture soil and temperature, precipitation, antecedent porates incor The PDSI equation. balance awater using monitored being region the in of moisture availability the it measures as drought, hydrological and of agricultural determinants are which conditions, ture mois soil and precipitation however, considers procedure drought, the of meteorological index an to as Step 2: Climatic coefficients 2: Climatic Step with computations moisture for soil model atwo-layered PDSI uses accounting. Hydrological 1: Step Step 4:Step Moisture anomaly index values 3: CAFEC Step precipitation, evapotranspiration, soil moisture loss and recharge, and runoff. and recharge, and loss moisture soil evapotranspiration, precipitation, parameters: five using of years out for along series carried is accounting hydrologic A monthly layers. the from and to of moisture transfer and capacity field concerning assumptions certain parameters listed in step 1, in order to assess the dimensionless index across space and time. and space across index dimensionless the order toassess 1, in step in listed parameters of the computed for each are (CAFEC), quantities conditions for appropriate existing matically cli or normal, These month. each during weather for “normal” required of moisture amount climate. local lyzed ana- the dependent on are which loss, and runoff, recharge, namely,evapotranspiration, ficients, Palmer Palmer ( anomaly of moisture toindices departures the converts then Dand as denoted computed and is tion) month for each  PDSI index and reflects the departure of the weather of a particular month from the average the average from month particular of a the weather of thedeparture reflects and Z index t widely used indices, especially in the United States, has been the PDSI [ the been has States, United the in especially indices, used t widely 17 ]. −4.0 or less −3.0 to −3.99 −2.0 to −2.99 −1.0 to −1.99 −0.5 to −0.99 TABLE 3.4 0.49 to −0.49 0.5 to 0.99 1.0 to 1.99 2.0 to 2.99 3.0 to 3.99 4.0 or more Source: . The series are reanalyzed using the derived coefficients to determine the determine to coefficients derived the using are reanalyzed series . The 32 Table 3.4 Table , 40 Equation 3.3 Equation

Mirabbasi, etal R. . The results of step 1 are summarized to compute four monthly coef compute to monthly four aresummarized 1 step of . The results ], as well as a previous PDSI value. In addition, the PDSI is standardized PDSI standardized is the addition, In PDSI value. aprevious as well ], as

The DroughtPalmer S . The precipitation departure (precipitation minus CAFEC precipita CAFEC minus (precipitation departure precipitation The . ). A brief conceptual description of the five steps for the computation computation the for steps five of the description ). conceptual Abrief ). This moisture anomaly index has come to be known as the as known be come to has index anomaly moisture ). This ., J. Hydrol., 492, 35, 2013. everity Index ClassificationScale Handbook of Drought and Water and Scarcity of Drought Handbook Near normal Incipient wet spell Slightly wet Moderately wet Very wet Extremely wet Extreme drought droughtSevere Moderate drought Mild drought Incipient spell dry 6, 21 ]. Although PDSI is referred PDSI referred is ]. Although 29 ]. The PDSI ------Downloaded By: 10.3.98.104 At: 20:03 30 Sep 2021; For: 9781315404219, chapter3, 10.1201/9781315404219-3 and its limitations stated earlier acknowledged [ acknowledged earlier stated limitations its and appropriately used if assessment, drought operational and research for tool both auseful be PDSI can the coefficients, standardized the some of of nature theempirical and deficiencies, and limitations other on an operational basis [ basis operational on an as well as studies, research countless in applied been has and internationally, as well as States, United [ variables predictor as temperature and precipitation ducts drought monitoring based on SPI and issues regular bulletins for the whole region [ whole region for the bulletins regular onissues SPI and based monitoring drought ducts con Slovenia, Ljubljana, in located Europe, East for South Center Management Drought the Similarly, systems. warning early and monitoring for drought indicators to implement more temperature-based flexibility for the allow also would indicators available the all considers that approach an Using DEWS. and monitoring for drought or season area particular for any suitable most the determine and available are that indices drought many toutilize possible it may be area, particular for any quality and ability [ of accuracy level the order toenhance in available, if information, Meteorological Drought Indices Drought Meteorological

sectors ( sectors hydrological and on agricultural impacts in results quickly humidity, low relative and winds, high tures, - tempera above-normal with association in sometimes of time, over alonger period conditions dry these of continuation A deficiencies. precipitation in result and causes multiple from originate which tions, condi atmospheric prevailing of the character variable, highly and regional, due tothe event, natural a regional as characterized is drought meteorological Indeed, drought. meteorological as considered usually are expected or from normal of precipitation departure accumulated of stages early These time. of period over a in a region of precipitation adeficiency with begin droughts all mentioned, already As 3.4 toring drought conditions through the use of drought indicators and indices [ indices and indicators of drought use the through conditions drought toring on moni focalize which DEWS, a functional establishing in critical it how becomes to applyand them, product [ product toasingle leading analysis for drought methodology a ranking todevelop frames, long-term time short- and various covering indicators of acomposite multiple Monitor uses (USDM)Drought system

Palmer’s procedure has been initially characterized as a very satisfactory solution by jointly using using by solution jointly satisfactory avery as characterized initially been has procedure Palmer’s As work toward developing drought indices continues, knowing which indices work best for a region for aregion work best indices which knowing continues, indices drought developing work toward As Step 5: Drought severity 5: Drought Step  where indices are computed by computed are indices where index is of Zindex equation The months. or prior subsequent in occurred has of what regardless month, for that climate moisture month, three intermediate indices (X indices intermediate three month, each for computing, involves The methodology periods. drought of the severity and ending, ning, Discussions Figure 3.1 Figure 39 Z K X is the precipitation departure precipitation the D is j j j represents accumulated values of the moisture anomaly index for the driest intervals driest for the index anomaly moisture of the values accumulated represents is the value of j PDSI for the value the is is the weight coefficient of month j of month coefficient weight the is ]. The USDM system has also the flexibility to integrate new tools and data and additional additional and data and tools new integrate to theflexibility also ].has The USDMsystem ). 23 , . In this final step, the Z step, final this . In 49 ]. Despite several assumptions made in the water balance calculations, its its calculations, balance water the in made assumptions ]. several Despite th month XX jj 1 =× , X 0 ZK . 2 897 1 , and X , and =× , 6, 23 -index series is analyzed to determine the begin the todetermine analyzed is series -index j ]. D 1 - 3 , 1

), and a probability factor. These intermediate intermediate factor. These aprobability ), and 21 + ]. The PDSI has become widely used in the in used widely ].become The has PDSI Z 3 j

48 ]. Depending on the data avail data on the ]. Depending 13 ]. The United States ]. States The United 3 ]. (3.4) (3.3) 39 - - - - - Downloaded By: 10.3.98.104 At: 20:03 30 Sep 2021; For: 9781315404219, chapter3, 10.1201/9781315404219-3 meteorological drought index [ index drought meteorological common the as Services Hydrological and Meteorological by National globally used computed and to be index drought the as recommended and by SPI WMO adopted is the that Indices” on Drought Declaration “Lincoln the via (November2009) 8–11, announced of Nebraska University at the workshop expert international An regions. between more order comparability toprovide in drought assess and tocalculate country for every point starting and standard minimum the tobe index drought logical meteoro for asingle arecommendation toput forward (WMO) wanted Organization Meteorological calculation of evapotranspiration. of calculation for even empirical inability tothe leads which parameter, input an as of temperature due tolack sis analy change toclimate SPI not applicable is the addition, component. In balance water no soil is there Moreover,data. on precipitation only computation theof based SPIis At first, haveconsidered. to be that given SPIvalue. any for climates different in locations different between comparability is there that means which consistent, spatially as sidered Moreover, severity. SPI con is of drought the assessment to the contribute can DEWS and provide can SPI, up toa3-month is, that SPIs, scale time shorter fact, In applications. and analyses drought logical or more for months 6up to24 hydro from and drought, for agricultural 1to6months from drought, tometeorological applicable a1- be or 2-month SPI can Indeed, anomalies. long-term precipitation the reflect groundwater and storage, reservoir Streamflow, scale. short on arelatively anomalies tion torespond precipita conditions moisture soil Specifically, water resources. different of the availability the on drought of impact the reflect which scales, time for deficit multiple precipitation the to quantify designed is since it The SPIflexible, is months. 1to24 from typically or window, ranging period desired 40 director of the Laboratory of Agrometeorology, University of Thessaly, Greece (1991–2011).Greece of Thessaly, University of Agrometeorology, He received Laboratory of the director (2011–today). founding Greece and professor He of Athens, was University Agricultural and Greece, Dalezios R. Nicolas Authors toglobal. local from scales, at all models risk drought credible tobuilding contribute eventually these All reduction. risk and management risk of elements drought critical certainly are measures insurance Moreover, disaster DEWSassessment. and risk drought toward step starting important an constitute impacts, and losses for drought account cally systemati as as well and monitoring, quantification for drought implement standards and to develop efforts international presenttime, At the models. risk drought global developing and risk drought ing address for continues interest international the difficulties, and limitations current these Despite ard. haz- drought modeling for data, suitable and of sufficient lack as well as constraints, data are there and internationally recorded systematically yet not are impacts However, drought regimes. precipitation and temperature both in ashift may be there which in climate for achanging account also can that indices discussed. also is universally be applied to recommendation and its WMO the the SPI by of adoption The presented. is indices drought meteorological used widely and of indicative A description considered. also is assessment and monitoring Drought indices. of use the through drought of meteorological quantification by followed the presented, been has characteristics, and features its with along drought, meteorological of description a Then, considered. been has types and definitions, concepts, of drought sive presentation comprehen a At first, addressed. been has indices drought of meteorological subject chapter, the this In 3.5 With some indices requiring large volumes of data and, thus, becoming more complex, the World more complex, the becoming thus, and, of data volumes large requiring indices some With Besides the previously described advantages for using SPI globally, there are also some drawbacks drawbacks some also are there SPI globally, for using advantages described previously the Besides for a records on long-term precipitation based is and location any The SPIregion computation for There is an international need to continue working toward newer and potentially better drought drought better potentially and newer toward working continue to need international an is There  Summary and ConclusionsSummary is professor of agrometeorology and remote sensing, University of Thessaly, of Thessaly, University Volos, remote sensing, and of professor agrometeorology is 51 ]. Handbook of Drought and Water and Scarcity of Drought Handbook ------Downloaded By: 10.3.98.104 At: 20:03 30 Sep 2021; For: 9781315404219, chapter3, 10.1201/9781315404219-3 International Scientific Journal Scientific International in reviewer and editor reports, technical and publications refereed 280 of more or than coauthor author the He is variability/change. climate and assessment, risk hazards, environmental modeling, sensing, remote agrohydrology, agrometeorology, in research recordin 1982). along-standing He has Canada, of (University Ontario, Waterloo, engineering civil in 1974) his PhD and received the Netherlands, Delft, of (University engineering 1972) hydrological (Athens, and meteorology in degrees postgraduate his Indices Drought Meteorological References ones. Handbook (2017) published Aqueducts Underground are Water Handbook Reuse Group (CRC Hydrology & Francis Handbook of Press). Engineering Athree-volume by Taylor published handbooks of several editorship the started has Eslamian Recently, Professor books. Engineering Flood of Journal and Inderscience) and Technology of Journal Hydrology Science International of both editor chief and founder the He is reports. technical or as books and journals in publications 500 tomore than contributed He has Canada. Quebec, University, Montreal, McGill 2014 from with partnership aresearch started he has side, research the On Switzerland. Zurich, of ETH University University, NewJersey, the and at Princeton professor Formerly, avisiting he was climate. achanging in hydrology environmental and statistical and management and planning resources on water mainly focuses research His Pilgrim. David of Professor supervision the under Australia, Wales, of NewSouth University the from PhD his 1995. He received since been of he has where Technology, University Iran, at Isfahan Water Engineering Saeid Eslamian Medal. Class 1st Defence For National the honors and of Hungarian Cross Knight’s the with awarded been He has events. scientific international several organized has He journals. scientific international in reviewer and editor as well as professor honorary He is publications. refereed numerous with assessment drought on studies including projects, research international several in (COST). participated Henology has tech and science in Union cooperation (EGU), and Geoscience WMO, European as such nizations, orga international in involved been He has toagriculture. impacts change climate and meteorology, agricultural in of remote sensing use modeling, agrometeorological include interests research His (1998–2001). Meteorology COST) (EC technology and science in cooperation commission European of secretary 2011–2013) (2005–2007 and scientific and Service Met Hungarian president of the was He (Hungary). University Kaposvar of lecturer invited as 1977–2013). he worked retirement, After Dunkel Zoltan assessment. and monitoring, analysis, on drought projects and articles research of numerous or coauthor author and chapters, book of 25

4. 2. 5. 3. 1.

Bhalme, H. N H. Bhalme, M Applied of Journal assumptions, and Limitations index: severity drought W.palmer The 1984. Alley M. Weather Review Washington, DC, 48pp. DC, Washington, K Z., Bihari, Areas (in Russian), Gidrometeoizdat, Leningrad, Soviet Union. Soviet Leningrad, (in Gidrometeoizdat, Russian), Areas 1 I. M. Budyko, matologic F Blaney, H. (HMS), pp. 37–41. Service Meteorological Hungarian summaries, Procekt, DMCSEE Hungary, in Droughts 2012. E. al and irrigation data, USDA Soil Conservation Service, Technical Paper No. Paper USDA, 96, Technical Service, USDA Conservation data, Soil irrigation and al is a full professor of hydrology and water resources engineering in the Department of Department the in engineering resources water and of professor hydrology afull is eteorology is a retired meteorologist with the Hungarian Meteorological Service (OMSZ; Service Meteorological Hungarian the with meteorologist aretired is . and Criddle, W. D. 1950. Determining water requirements in irrigated areas from cli from areas irrigated in requirements water W. Criddle, D.. and 1950. Determining ovács, T., Lakatos, M., Móring, A., Nagy, A., Németh, Á., Szentimrey, T., and Vincze, T., Vincze, Szentimrey, and Á., Németh, A., Nagy, A., Móring, M., T.,ovács, Lakatos, . and Mooley, D. A. 1980. Large-scale drought/floods monsoon circulation, Monthly circulation, monsoon drought/floods Mooley,. and D. 1980. Large-scale A. 952. Climate change and national plan of environment modification of Arid USSR USSR Arid of modification of environment plan national and change 952. Climate , 108: 1197–1211. (2017), Water and Scarcity and Drought of Handbook athree-volume 2015, in , 23: 1100–1109. , author of two books, editor or coeditor of 15 edited books and coauthor coauthor and books edited of 15 or coeditor editor books, of two , author . He has authored more than 100 book chapters and and chapters 100 book more than authored . He has Urban 2014, in Urban (Scopus, (Scopus, 41 - - ­ Downloaded By: 10.3.98.104 At: 20:03 30 Sep 2021; For: 9781315404219, chapter3, 10.1201/9781315404219-3 42

20. 24. 22. 25. 23. 16. 10. 14. 19. 18. 12. 21. 17. 15. 13. 11. 6. 9. 8. 7.

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Ecology,36: Bulletin of the American Meteorological Society Meteorological American the of Bulletin indices, Keyantas 25(1): 77–86. evapotranspiration, potential including coefficients calibration T. 19 Karl, R. pp. 23–59, 448pp. City, Luxembourg, Luxembourg PRODIM ed., report G., final Tsakiris, in: indices, drought lite Kanellou Earth of the Chemistry and Physics climate, global to relation and behaviour statistical interpretation, Physical I Szép, Jankó Water Research Resources requirements, water for evaluating R Jackson, Water indicator, Research Resources stress water R Jackson, 249–256. Meteorology Forest and Agricultural variability, for environmental concept stress-degree-day Ja B., S. Idso, Society Meteorological American the of Bulletin J R.R. Heim, Australia. 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