** ⦽᧲ݡ⦺Ʊ ݡ⦺ᬱ Õᖅ⪹ĞŖ⦺ŝ ᕾᔍŝᱶ ([email protected])
Received April 8, 2013/ revised May 8, 2013/ accepted June 11, 2013
Copyright ⵑ 2013 by the Korean Society of Civil Engineers
ǣǣȀȀǤǤȀͳͲǤͳʹͷʹȀ ǤʹͲͳ͵Ǥ͵͵ǤͷǤͳͺͷͳ
Ǥ ǤǤ
ⴺ#ᢦⳂ#SPI⯾#ROC ⍂⛛ⴂ#ⴲⱧ㬚#ᢦᏮᆾℂⴖ#㦇ᆾ
କઽ ȵ ȵ૽ ȵੲ୍෮
Yoo, Ji Young*, Song, Hoyong**, Kim, Tae-Woong***, Ahn, Jae-Hyun****
Evaluation of Short-Term Drought Using Daily Standardized Precipitation Index and ROC Analysis
ABSTRACT
The Standardized Precipitation Index (SPI) is widely applied to evaluate for meteorological droughts. However, the SPI is limited to capture a drought event with a short duration, expecially shorter than one month. In this study, we proposed a daily SPI (DSPI) as a way to overcome the limitation of the monthly SPI for drought monitoring. In order to objectively assess the ability of the drought reproduction of the DSPI, we performed a receiver operating characteristic (ROC) analysis using the quantified drought records from official reports, newspapers, etc. The results of ROC analysis showed that the DSPI has an ability to reproduce short-term drought compared with other indices. It also showed that the main cause of historical droughts was the shortage of rainfall accumulated during the time period less than 90 days compared with the rainfall of normal years.
Key words : Short-Term drought, Daily standardized precipitation index, ROC analysis
Ⅹಾ
SPI(Standardized Precipitation Index)۵ĥᔑᱩ₉ae݉⦹ʑভྙᨱʑᔢ⦺ᱢaྥᮥ⠪a⦹۵ߑŲჵ᭥⦹íᔍᬊࡹŁᯩ݅. ə్ӹᬵ݉
᭥ʑၹᮝಽᔑᱶࡹʑভྙᨱ1ݍᯕԕ᮹Ṉᮡḡᗮʑeᮥaḡ۵aྥᔍᔢᮥ⡍₊⦹ḡ༜⦹۵݉ᱱᮥaḡŁᯩ݅. ᅙᩑǍᨱᕽ۵ᬵ݉᭥ಽĥ ᔑࡹ۵SPI᮹݉ᱱᮥɚᅖ⦹ʑ᭥⦽ႊᦩᮝಽᯝ݉᭥SPI(DSPI)ෝᱽᦩ⦹ᩡ݅. ੱ⦽, DSPI᮹aྥᰍ⩥܆ಆᮥ~šᱢᮝಽ⠪a⦹ʑ᭥⧕ŝ Ñ᮹aྥၽᔾʑಾᮥᯕᬊ⦹ᩍROC ᇥᕾᮥᙹ⧪⦹ᩡ݅. ᯕෝၵ┶ᮝಽᬑญӹ᮹݉ʑaྥᮥᰍ⩥⦹۵ߑᱢᱩ⦽ḡᗮʑeᮥᱽ⦹ᩡᮝ໑, aྥ᮹ၽᔾᮁྕෝđᱶ⦹۵ߑ⪽ᬊ⦹۵3aḡ॒ɪ(ᅕ☖, ᝍ⦽, ɚ⦽aྥ)ᄥDSPI᮹aྥᩩᅕ܆ಆᮥá☁⦹ᩡ݅. əđŝ3aḡ॒ɪᨱݡ⦽
ᰍ⩥܆ಆᯕᬑᙹ⦽aྥḡᗮʑeᮥđᱶ⦹ᩡ݅. ੱ⦽, ŝÑ2000֥ᯕ⬥ᨱၽᔾ⦽ᬑญӹݡᇡᇥ᮹aྥᮡ90ᯝ(3}ᬵ) ᯕԕ᮹٥ᱢvᙹప ᯕ⠪֥᮹ᙹᵡᨱእ⦹ᩍᇡ᳒⦹ʑভྙᨱၽᔾ⦽ʑᔢ⦺ᱢ⊂໕᮹݉ʑaྥᯙäᮝಽӹ┡ԍ݅.
áᔪᨕ ݉ʑaྥ, ᯝ݉᭥SPI, ROC ᇥᕾ
1. ᕽು
⩥ᰍ ᱥ ᖙĥᱢᮝಽ ʑ⬥ᄡ⪵ಽ ᯙ⦽ ݡȽ༉ aྥ᮹ ၽᔾ a܆ᖒᯕ ׳ᦥḡŁ ᯩᮝ໑, ᬑญӹࠥ ᩩ۵ ᦥܩ݅. ᯕ۵ ᱥḡǍᱢ
᪉ӽ⪵⩥ᔢ᮹ᩢ⨆ᮝಽᬑญӹ۵vᙹప᮹qᗭ᪡ᇩᨕ᷾ၽపࠥⓍí᷾a⦹Łᯩᮝ໑, đǎaྥŝšಉࡽ⦝⧕ࠥᬒ⍅ḩ
սėॡ
äᯕ݅(Choi et al., 2008). ੱ⦽, aྥᮡə✚ᖒᔢ݅ෙᯱᩑᰍ⧕᪡
۵ݍญḥ⧪ᗮࠥa۱ญအಽ·Ŗeᱢᮝಽᱶ⪶⦹í❱݉⦹ʑ
ᛞḡ ᦫ݅.
ᯝၹᱢᮝಽaྥᮡⓍí4aḡᬱᯙᮝಽǍᇥ⦹໑, ᯕ۵vᙹప ᮹ᇡ᳒ᮥᬱᯙᮝಽ⦹۵ʑᔢ⦺ᱢᯙaྥ, ḡ⢽ᙹၰḡ⦹ᙹ᮹
ᇡ᳒ᮥᬱᯙᮝಽ⦹۵ᙹྙ⦺ᱢaྥ, ☁᧲ᙹᇥ᮹ᇡ᳒ᮥᬱᯙᮝಽ
⦹۵ᨦᱢaྥ, ᬊᙹၰᱥಆŖɪ᮹ᱽ⦽ᮥᬱᯙᮝಽ⦹۵ᔍ⫭Ğ ᱽ⦺ᱢ aྥᯕ݅. ᯕ్⦽ aྥᮡ ᵝಽ aྥḡᙹᨱ ᮹⧕ ᔢ⫊ᮥ
❱݉⦹໑, ⩥ᰍʭḡ݅᧲⦽aྥḡᙹॅᯕ}ၽࡹᨩ݅. ᬑญӹࠥ
aྥᨱ ݡ⦽ ฯᮡ ᩑǍॅᯕ ḡᗮᱢᮝಽ ḥ⧪ࡹŁ ᯩᮝ໑(Yoo, 2006; Kim and Yoo, 2006; Yoo et al., 2008; Choi and Kim, 2010; Kim and Lee, 2011; Kim et al., 2011; Ahn et al., 2012),
⢽ᵡvᙹḡᙹ(Standardized Precipitation Index, SPI), ❭ນaྥ
ḡᙹ(Palmer Drought Severity Index, PDSI), ḡ⢽ᙹŖɪḡᙹ (Surface Water Supply Index, SWSI) ॒ᯕݡ⢽ᱢᮝಽ⪽ᬊࡹŁ
ᯩ݅.
ᯕౝaྥᮥᱶ᮹⦹Ł❱݉⦹ʑ᭥⦽༊ᱢᮝಽ⪽ᬊࡹ۵݅᧲
⦽aྥḡᙹᵲᨱᕽSPI۵݅ෙḡᙹॅŝእƱ⦹ᩍaྥḡᙹෝ
ĥᔑ⦹۵ŝᱶᨱᕽᬵvᙹప ᯱഭอᮥᯕᬊ⦹ʑভྙᨱእƱᱢ
ᯱഭǍ⇶ᨱ ݡ⦽ ᱽ᧞᳑Õᯕ ᱢ݅. ੱ⦽ ݅᧲⦽ eࠥ(time scale)ෝŁಅ⦹ᩍĥᔑ⧁ᙹᯩʑভྙᨱ݉ʑၰᰆʑᱢᯙvᙹ
ᇡ᳒పᮥ⠪a⧁ᙹᯩ۵ᰆᱱᯕᯩ݅. ə్ӹSPI۵ᬵ݉᭥ಽ
ĥᔑࡹʑভྙᨱṈᮡʑe࠺ᦩ᮹ᙹྙ⦺ᱢᄡ࠺ᖒᮥŁಅ⦹ḡ
༜⦹۵⦽ĥaᯩ݅. ✚⯩1}ᬵᯕԕᨱ݉ʑaྥᔍᔢᯕၽᔾ⦹Ł
⧕ᗭࡹ۵ Ğᬑෝ ⡍₊⦹ḡ ༜⦹۵ Ğᬑa ᳦᳦ ၽᔾ⦽݅. ᩩෝ
ॅᨕ, 5ᬵ1ᯝⓑvᙹaၽᔾ⦽⬥, 5ᬵ2ᯝᇡ░6ᬵ29ᯝʭḡ
vᙹaԕญḡᦫ۵݅໕ᝍ⦽aྥ(severe drought)ᯕၽᔾ⧁ᙹ
ᯩᮝӹ, 6ᬵ30ᯝᨱੱ݅ⓑvᙹaၽᔾ⦽݅໕ᬵ݉᭥ʑၹ᮹
aྥḡᙹᨱᕽ۵ ⧕ݚ aྥ ᔢ⫊ᮥ ⢽⇽ࡹḡ ༜⦹í ࡽ݅.
ᅙᩑǍᨱᕽ۵ʑ᳕᮹ᬵ݉᭥SPIaw۵ᱢᬊᔢ᮹⦽ĥෝɚᅖ⦹
Ł݉ʑaྥᮥ⠪a⦹ʑ᭥⦹ᩍᯝ݉᭥᮹٥ᱢvᙹపᮥʑၹᮝಽ
vᙹᇡ᳒ᇥᮥĥᔑ⦹ᩍᯝ݉᭥SPIෝ}ၽ⦹ᩡ݅. ੱ⦽, ݅᧲⦽
eࠥᄥᯝ݉᭥SPIᨱݡ⦽ᱢᬊᔢ᮹⬉ᮉᖒᮥá☁⦹ʑ᭥⧕
ROC(Receiver Operating Characteristic) ᇥᕾᮥ ᝅ⦹ᩡ݅.
ROC ༉⩶ᮡᵝಽʑᔢᇥᨱᕽ⪶ශᩩᅕ᮹ᱶᖒᱢá᷾ᨱ⪽ᬊࡹ۵
ʑჶᯕ݅(Mason, 1982). Kim and Lee (2011)۵ᝅᱽaྥᔍಡ᪡
aྥḡᙹ᪡᮹ᱶపᱢᯙ⠪aෝ᭥⧕☖ĥᱢʑჶᯙROC ᇥᕾᮥ
ᱢᬊ⦽ၵᯩ݅. ᯕ్⦽ROC ᇥᕾᮥ᭥⧕ᕽᅙᩑǍᨱᕽ۵2000֥
ᯕ⬥(2000֥, 2001֥, 2008֥, 2009֥, 2012֥) ᬑญӹᨱᕽᝅᱽ
ၽᔾ⧩ ݉ʑaྥ ʑಾᮥ ᩍ్ aḡ aྥšಉ ᅕŁᕽ ၰ ᨙು
ᅕࠥᯱഭ॒ᮥ⪽ᬊ⦹ᩍᙹḲ⦹ᩡᮝ໑, ݅᧲⦽eࠥෝaḡ۵
ᯝ݉᭥SPI᪡እƱᇥᕾ⦹ᩡ݅. ᯕ۵݉ʑaྥᮥ⠪a⧁ᙹᯩ۵
aྥḡᙹෝ}ၽ⦹Ł⪽ᬊ⦹ʑ᭥⦽ʑⅩᩑǍಽᕽᯝ݉᭥aྥḡᙹ
ෝ ʑၹᮝಽ ⦽ ⬉ᮉᱢᯙ aྥ ༉ܩ░ยᮥ a܆⍡ ⧁ äᯕ݅.
2. ᯝ݉᭥SPIෝᯕᬊ⦽aྥ✚ᖒᇥᕾ
2.1 ԧࢇଭ୨ଭࢫଵۚSPI Թڄ
vᙹ᮹ ᇡ᳒ᮡ aྥ᮹ ᵝࡽ ᯙᯕ ⧁ ᙹ ᯩᮝ໑, aྥ᮹
ᱶపᱢ ⠪aᨱ ⬉ŝᱢᮝಽ ᯕᬊࡹŁ ᯩ݅. ᷪ ⠪Ɂᱢᯙ ᙹᵡᮥ
ᖅᱶ⦹Ł, ᯕෝʑᵡᮝಽaྥᮥᱶ᮹⦹Łaྥᔍᔢ᮹ḡᗮʑe, ᝍࠥ, ၽᔾኩ॒ࠥᮥᱶప⪵⦽⬥, ĥᩕᇥᕾჶᮥᯕᬊ⦹ᩍaྥ᮹
✚ᖒᮥ ᇥᕾ⦹۵ äᯕ݅.
ᯝၹᱢᮝಽaྥ᮹݉ʑၰᰆʑᱢᯙ✚ᖒᮥᅖ⧊ᱢᮝಽ⧕ᕾ⦹
ʑ᭥⦹ᩍᬵᄥvᙹపĥᩕᮥ݅᧲⦽eࠥ(3, 6, 9, 12}ᬵ
॒)᮹٥avᙹĥᩕᮥǍᖒ⦹Ł, beࠥᄥvᙹᇡ᳒పᮥ
ĥᔑ⦹ᩍᬵ݉᭥SPI(Monthly SPI, MSPI)ෝᔑᱶ⦽݅(McKee et al., 1993). ə్ӹMSPIෝᯕᬊ⦹ᩍaྥ⠪aෝᙹ⧪⧁Ğᬑ, Ṉᮡḡᗮʑeᮥaḡ۵aྥ⩥ᔢᮥᖅ⦹۵ߑᨱ۵⦽ĥaᯩ݅.
ᯕᨱᅙᩑǍᨱᕽ۵ᯝ݉᭥SPIෝ}ၽ⦹ᩍᬵ݉᭥SPIaaḡ۵
ᱢᬊᔢ᮹ ⦽ĥᱱᮥ ᅕ᪥⧁ ᙹ ᯩ۵ ႊᦩᮥ ᱽ⦹Łᯱ ⦽݅.
ᯝ݉᭥SPI᮹}ֱᮡᬵ݉᭥SPI᪡}ֱᱢᮝಽ۵࠺ᯝ⦹໑, SPI᮹ĥᔑᮥ᭥⧕٥avᙹĥᩕᮥǍ⇶⧁Ğᬑᨱᯝvᙹప (daily precipitation)ᮥ݅᧲⦽eࠥෝŁಅ⦹ᩍᯝᄥ٥av ᙹĥᩕ(daily cumulative precipitation time series)ᮥǍᖒ⦽
݅. ᯝᄥ٥avᙹ᮹⪶ශᇥ⡍⧉ᙹෝ⇵ᱶ⦹ᩍ, ٥a⪶ශsᨱ⧕ݚ
⦹۵⢽ᵡᱶȽᄡపᮥ⇵ᱶ⦹໕, ᯝ݉᭥SPI(Daily SPI, DSPI)a
ࡽ݅. ᅙ ᩑǍᨱᕽ۵ Gamma ᇥ⡍᮹ ⪶ශၡࠥ⧉ᙹ(Eq. (1))᪡
٥ᱢᇥ⡍⧉ᙹ(Eq. (2))ෝ ᯕᬊ⦹ᩍ ᬑญӹ 228} ⧪ᱶǍᩎᄥ
MSPI ၰDSPIෝ༉ࢱᔑᱶ⦹ᩡ݅. DSPIෝᔑᱶ⦹۵ŝᱶᨱᕽ
Gamma ᇥ⡍᮹ᱢ⧊ࠥáᱶᮥᙹ⧪⦽đŝ, 228}⧪ᱶǍᩎᄥ
DSPIෝ ĥᔑ⦹۵ ߑ ᱢᬊࡹᨕḥ ⅾ 365}᮹ Gamma ᇥ⡍⧉ᙹ
ᵲݡᇡᇥᯕᱢ⧊ࠥáᱶ(Chi-Square Test᪡Kolmogorov-Smirnov Test)ᮥ ☖ŝ⦹۵ äᮝಽ ⪶ᯙࡹᨩ݅.
ƄÞƖßá ć ķġÞĸß Î Þ ć ķ Ɩ ßĸ àÎ Þ à ćķ Ɩ ß (1)
ÞƖß á
õ×ƖƄÞƖßƂƖá
õ×Ɩć ķġÞĸß Î
Þ ćķ Ɩ ß
ĸ àÎÞà ć ķ Ɩ ß ƂƖ
(2)ᩍʑᕽ,
ķ
۵⇶ๅ}ᄡᙹ(scale parameter),ĸ
۵⩶ᔢๅ}ᄡ ᙹ(shape parameter),ġÞĸß
۵qษ⧉ᙹ(Gamma function)ᯕ݅.Table 1. Definition of the SPI Classes and Corresponding Event Probabilities
SPI interval SPI classes Occurrence probability (%) More than 2.00 Extreme wet 2.3
1.99 to 1.50 Severe wet 4.4 1.49 to 1.00 Moderate wet 9.2 0.99 to -0.99 Normal 68.2 -1.00 to -1.49 Moderate drought 9.2 -1.50 to -1.99 Severe drought 4.4 Less than -2.00 Extreme drought 2.3
Fig. 1. Thiessen Polygons to Transform Point Rainfalls() Into Fig. 2. Daily SPI and Monthly SPI for Gyeongsangnamdo (Time Table 1ᮡ᭥᪡zᮡŝᱶᮥ☖⧕ᔑᱶࡽDSPI᮹॒ɪᇥඹʑᵡ
ᮝಽ aྥ᮹ ᝍࠥෝ ❱݉⦹۵ ʑᵡᯕ ࡽ݅.
2.2 ෘ୨֜લଵۚSPI ॺ୨ࢫୡনՑഠ
ᯝၹᱢᮝಽḡᩎᱢaྥšญෝ᭥⦹ᩍ⧪ᱶǍᩎᨱෙḡᯱℕ aaྥݡ᮲ၰ⦝⧕ᅖǍෝᙹ⧪⦹Łᯩᮝӹ, ᝅᱽaྥᮥ❱݉⦹۵ ߑ⪽ᬊࡹ۵aྥḡᙹ᮹ݡᇡᇥᮡvᬑš⊂ḡᱱᮥʑᵡᮝಽĥᔑࡹŁ ᯩ݅. ə్အಽ ᅕ݅ ⬉ᮉᱢᯙ aྥšญෝ ᭥⧕ᕽ۵ ᝅᱽ
⧪ᱶǍᩎᄥvᙹ✚ᖒᮥၹᩢ⦹۵⧪ᱶǍᩎᄥaྥḡᙹ᮹ᔑᱶᯕ
⦥⦹݅. ᯕෝ ᭥⧕ᕽ ᅙ ᩑǍᨱᕽ۵ ᬑญӹ ʑᔢℎ ᔑ⦹᮹
57}vᬑš⊂ᗭᄥvᙹపᮥFig. 1ŝzᯕ❑ᖝᮥᯕᬊ⦹ᩍ
⧪ᱶǍᩎᄥ໕ᱢ⠪ɁᯝvᙹపᮝಽǍ⇶⦽⬥, ᯕෝʑၹᮝಽ⧪ᱶ Ǎᩎᄥ SPIෝ ĥᔑ⦹ᩡ݅.
ᬑญӹ۵vᬱᩢ࠺, vᬱᩢᕽ, ᕽᬙĞʑ, ∊ℎᇢࠥ, ∊ℎԉࠥ, Ğᔢᇢࠥ, Ğᔢԉࠥ, ᱥᇢࠥ, ᱥԉࠥḡᩎᮝಽⅾ9}᮹ݡǭᩎ, ᖙᇡᱢᮝಽ۵ⅾ228}ǑǍಽǍᇥࢁᙹᯩ݅. ᅙᩑǍᨱᕽ۵
228} ⧪ᱶǍᩎᄥ aྥ᮹ ⠪aෝ ༊ᱢᮝಽ ᯝ vᙹపᮥ 6aḡ
eࠥ(30ᯝ, 60ᯝ, 90ᯝ, 120ᯝ, 150ᯝ, 180ᯝ)᮹ᯝᄥ٥av ᙹĥᩕᮥǍᖒ⦹Ł, Gamma ᇥ⡍᮹⪶ශᇥ⡍⧉ᙹ᮹٥a⪶ශs ᨱ⧕ݚ⦹۵⢽ᵡᱶȽᄡపᮥ⇵ᱶ⦹ᩍ⧪ᱶǍᩎᄥDSPI(SPI_D30, SPI_D60, SPI_D90, SPI_D120, SPI_D150, SPI_D180)ෝĥᔑ
⦹ᩡ݅. ੱ⦽᭥᮹6aḡeࠥᨱᔢ᮲⦹۵MSPI(SPI_M1, SPI_M2, SPI_M3, SPI_M4, SPI_M5, SPI_M6)ෝ⧪ᱶǍᩎᄥಽ
ĥᔑ⦹ᩡ݅. ⧪ᱶǍᩎᄥDSPIෝᬵᄥಽ⠪Ɂ⦽⬥MSPI᮹እƱ⦽
đŝ, DSPI᮹ ⠪Ɂŝ MSPI۵ ݡᇡᇥ 9} ݡǭᩎᨱᕽ እ⦽
ᄡ࠺ᖒᮥaḡ۵äᮝಽӹ┡ԍ݅. ၹ໕, ࢱaྥḡᙹ᮹↽ݡၰ
↽ᗭ⊹۵MSPIᨱእ⦹ᩍDSPIᨱᕽ༉ࢱⓍíӹ┡ӹ, DSPIa
ɚ⦽ᮅၰɚ⦽aྥᮥӹ┡ԕ۵ߑᯩᨕᅕ݅⬉ŝᱢᯙäᮝಽ
⪶ᯙࡽ݅(Fig. 2 ₙŁ).
✚⯩ࢱaྥḡᙹᨱݡ⦽↽ᗭ⊹(ɚ⦽aྥ)ෝá☁⦹໕, 6aḡ
eࠥᨱෙDSPIᨱᕽ༉ࢱⓑᱩݡsᮥӹ┡ԕᨩ݅. ᩩෝ
ॅᨕ, SPI_D30᪡SPI_M1ᮥእƱ⧩ᮥĞᬑᨱ۵∊ℎԉࠥḡᩎᨱ ᕽaᰆⓑ₉ᯕ(0.956)ෝӹ┡ԕ۵äᮝಽ⪶ᯙࡹᨩᮝ໑, SPI_D60
᪡ SPI_M2ෝእƱ⧩ᮥĞᬑᨱ۵∊ℎᇢࠥḡᩎᨱᕽaᰆⓑ₉ᯕ (0.885), SPI_D90᪡SPI_M3ᮥእƱ⧩ᮥĞᬑᨱ۵ᱥᇢࠥḡᩎ ᨱᕽaᰆⓑ₉ᯕ(0.920), SPI_D120᪡SPI_M4, SPI_D150᪡
SPI_M5, SPI_D180᪡SPI_M6ෝእƱ⧩ᮥĞᬑᨱ۵༉ࢱᕽᬙĞ ʑ ḡᩎᨱᕽ ⓑ ₉ᯕ(0.676, 0.676, 0.545)ෝ ӹ┡ԙ݅.
ੱ⦽ࢱaྥḡᙹᨱݡ⦽↽ݡ⊹(ɚ⦽ᮅ)ෝá☁⦹໕, 6aḡ
eࠥᨱ ෙ DSPIᨱᕽ ༉ࢱ ⓑ ᱩݡsᮥ ӹ┡ԕᨩᮝ໑, SPI_D30᪡SPI_M1, SPI_D60᪡SPI_M2ෝእƱ⧩ᮥĞᬑᨱ۵
Table 2. Correlation Coefficients Between Minimum Value of Daily SPI and Monthly SPI SPI_D30
(SPI_M1)
SPI_D60 (SPI_M2)
SPI_D90 (SPI_M3)
SPI_D120 (SPI_M4)
SPI_D150 (SPI_M5)
SPI_D180 (SPI_M6)
Gangwon Youngdong 0.556 0.768 0.827 0.866 0.860 0.881
Gangwon Youngseo 0.522 0.794 0.851 0.891 0.896 0.917
Seoul Gyeonggi 0.534 0.762 0.830 0.859 0.860 0.869
Chungcheongbukdo 0.546 0.772 0.840 0.874 0.880 0.890
Chungcheongnamdo 0.548 0.778 0.849 0.881 0.888 0.897
Gyeongsangbukdo 0.528 0.766 0.840 0.885 0.890 0.902
Gyeongsangnamdo 0.545 0.788 0.851 0.890 0.902 0.918
Jeollabukdo 0.539 0.785 0.854 0.880 0.887 0.902
Jeollanamdo 0.532 0.775 0.837 0.873 0.876 0.904
(a) May 2012 (b) June 2012
Fig. 3. Daily SPI and Monthly SPI for Seoul·Gyeonggi Region Ğᔢԉࠥḡᩎᨱᕽaᰆⓑ₉ᯕ(1.073, 1.110)ෝӹ┡ԕ۵äᮝಽ
⪶ᯙࡹᨩᮝ໑, SPI_D90᪡SPI_M3, SPI_D120᪡SPI_M4ෝእ Ʊ⧩ᮥĞᬑᨱ۵vᬱᩢ࠺ḡᩎᨱᕽaᰆⓑ₉ᯕ(0.704, 0.653), SPI_D150᪡SPI_M5ෝእƱ⧩ᮥĞᬑᨱ۵Ğᔢԉࠥḡᩎᨱᕽ
aᰆⓑ₉ᯕ(0.603), SPI_D180᪡SPI_M6ᮥእƱ⧩ᮥĞᬑᨱ۵
ᱥԉࠥ ḡᩎᨱᕽ aᰆ ⓑ ₉ᯕ(0.529)ෝ ӹ┡ԙ݅.
Table 2۵ࢱaḡSPI᮹ᔢšĥᙹෝᱶญ⦽äᮝಽ, ᩍʑᕽ
MSPI᪡እƱࡹᨕḥDSPI۵ᬵᄥ↽ᘀs(ᮭ᮹s)ᮥᯕᬊ⦹ᩡ݅.
ə đŝ, ✚⯩ 90ᯝ ᯕ⦹ ʑe ࠺ᦩ᮹ ٥ᱢ vᙹపᮥ ᯕᬊ⦹ᩍ
ĥᔑ⦽SPI_D30(vs SPI_M1), SPI_D60(vs SPI_M2), SPI_D90 (vs SPI_M3)ᮡԏᮡᔢšᖒᮥӹ┡ԕᨩᮝӹ, 90ᯝᮥⅩŝ⦹۵
ʑe࠺ᦩ᮹٥ᱢvᙹపᮥᯕᬊ⦹ᩍĥᔑ⦽SPI_D120(vs SPI_M4), SPI_D150(vs SPI_M5), SPI_D180(vs SPI_M6)ᮡᔢݡᱢᮝಽ
ᔢšᱶࠥaᱱ₉Ⓧíӹ┡ӹ۵äᮥ⪶ᯙ⧁ᙹᯩ݅. ᯕ۵ᰆʑe᮹
٥ᱢ vᙹపᮥ ᯕᬊ⦹ᩍ ᰆʑ aྥᮥ ⠪a⧁ Ğᬑᨱ۵ ၹऽ
ࢱaḡSPIෝǍᇥ⦹ᩍᔍᬊ⧕⧁⦥۵ᨧḡอ, 3}ᬵၙอ᮹
݉ʑaྥᮥ⠪a⧁Ğᬑᨱ۵ᯝ݉᭥SPIෝၹऽá☁⧕⧁
⦥a ᯩᮥ äᯕ݅.
ᩩෝॅᨕ, ḡӽ1973֥4ᬵvᬱࠥv෪aྥᮥSPI_M1 (0.542)ᮥᯕᬊ⦹ᩍ⠪a⦽݅໕, ⢽1᮹Ǎᇥᨱᱶᔢ(Normal) ᔢ┽Ł❱݉ࡽ݅. ၹ໕, ࠺ᯝᱱᯙ1973֥4ᬵ᮹ᯝᄥSPI_D30 ɚ⦽(Extreme) aྥᔢ┽ᯕ໑, 4ᬵ24ᯝᨱ۵4ᬵᵲ↽ݡs(0.721) ᯕĥᔑࡹᨕᱶᔢ(Normal) ᔢ┽ಽ⪶ᯙࡹᨩ݅. ᯕ۵4ᬵᵲᙽᨱ
ԕฑvᙹపᮝಽᯙ⧕4ᬵⅩʭḡḡᗮࡹᨩaྥᔢ┽a⧕iࡹᨕ
MSPI۵ᱶᔢ(Normal) ᔢ┽ᯙäᮝಽ⢽⩥ࡽäᯕӹ, ᝅᱽaྥ᮹
᯲ၰ⧕i᮹ᱱᮥᱶ⪶⦹í❱݉⦹ʑ᭥⧕ᕽ۵DSPIෝᯕᬊ⦽
aྥ ༉ܩ░ย᮹ ⦥ᖒᮥ ᰍ⪶ᯙ ⧁ ᙹ ᯩ݅.
ᅙ ᩑǍᨱᕽ ᱽᦩ⦽ DSPIෝ ⪽ᬊ⦹۵ aྥ⧕ᕾ᮹ ᱢᬊᖒᮥ
ᬑญӹᨱᕽᝅᱽಽၽᔾ⦽2012֥ᅥaྥᮥݡᔢᮝಽá☁⦹ᩡ
݅. 2012֥5ᬵ1ᯝᇡ░6ᬵ27ᯝʑe࠺ᦩ, ᱥǎᱢᮝಽԕฑ
vᙹపᮡ⠪֥(248mm)᮹28.7%(71.2mm)ᨱᇩŝ⦽ᙹᵡᯕᨩᮝ
(a) June 23 (b) June 24 (c) June 25
(d) June 26 (e) June 27 (f) June 28
(g) June 29 (h) June 30
໑, ᯕಽᯙ⧕ᅥaྥᯕၽᔾ⦽ၵᯩ݅. ✚⯩, ᕽᬙḡᩎᨱᕽ۵
࠺ᯝ⦽ʑe࠺ᦩᱥǎᨱᕽaᰆᱢᮡvᙹప(10.6mm)ᯕԕಙ݅Ł
ᅕŁࡹᨩ݅(Ahn, et al., 2012). Fig. 3ᮡ2012֥ᅥaྥᯕၽᔾ⦽
5ᬵŝ6ᬵᨱݡ⦽ᕽᬙĞʑḡᩎ᮹MSPI ၰDSPIෝӹ┡ԕ໑, ᩍʑᕽၶᜅ⥭ᮡ⧕ݚᬵ᮹DSPIᯕŁ, ၶᜅ⥭ԕ⢽ʑࡽᱱᮡ
⧕ݚ ᬵ᮹ MSPIᯕ݅.
Fig. 3(a)᪡Fig. 3(b)᮹đŝෝእƱ⦹ʑᨱᦿᕽvᙹၽᔾ✚ᖒ
ᮥⓍíࢱaḡಽǍᇥ⧕⦽݅. ᷪ, ⦽ݍԕԕvᙹaԕญḡ
ᦫ۵ Ğᬑ᪡ ⧕ݚ ᬵ ԕ ✚ᱶ ʑe ࠺ᦩ ∊ᇥ⦽ vᙹa ԕญ۵
Ğᬑಽӹڽ݅. ᝅᱽḡӽ2012֥5ᬵᮡᱥᯱ᮹Ğᬑᯕ໑, 6ᬵᮡ
⬥ᯱ᮹Ğᬑಽᕽ2012֥6ᬵ29ᯝŝ30ᯝᨱÑℱ30mmⴇ110mm ᮹vᙹaၽᔾ⦹ᩡ݅. ᷪ, ᱥᯱ᮹Ğᬑᨱ۵MSPI᪡DSPI۵༉ࢱ
ɚ⦽ aྥᔢ┽ಽ ⢽⩥ࡹŁ ᯩᮝӹ(Fig. 3(a)), ⬥ᯱ᮹ Ğᬑᨱ۵
DSPIa⢽⩥⦹۵ɚ⦽aྥᔢ┽ෝMSPI۵ɚ⦽aྥᔢ┽ෝ⢽⩥
Table 3. ROC Model
Previous drought records Drought Non-drought Drought Index
(SPI)
Drought Hit (H) False (F) Non-drought Missing (M) Negative hit (N)
Fig. 5. ROC Curve
⦹۵ ߑ⦽ĥa ᯩ۵äᮝಽ ⪶ᯙࡽ݅. ᯕ۵ MSPIෝ ᔑᱶ⦹۵
ߑ ᯩᨕ, 6ᬵ᮹ ᮅʑe(2012֥ 6ᬵ 29ᯝŝ 30ᯝ: 30mmⴇ 110mm vᙹၽᔾ) ࠺ᦩᨱԕฑᯝvᙹపᯕ⡍⧉ࡽᬵvᙹపᮥ
ᯕᬊ⦹ᩍMSPIaĥᔑࡽäᯕʑভྙᯕ݅. ə్အಽ⧪ᱶǍᩎᄥ
DSPI۵aྥᮥḥ݉⦹Ł⠪a⦹۵ߑᯩᨕ, ʑ᳕ᬵ݉᭥aྥḡᙹ
ෝᯕᬊ⦽aྥ⠪aႊჶŝእƱ⦹ᩍᅕ݅ᔢᖙ⦽eࠥ(ᯝ݉᭥) ᮹aྥ༉ܩ░ยᯕa܆⦹݅. ੱ⦽, DSPIෝ⪽ᬊ⦽aྥ⠪aෝ
☖⧕Õ᳑⦽ᔢ┽aᮅ⦽ᔢ┽ಽᄡ⪵ࡹ۵aྥ⧕ᗭŝᱶ᮹༉ܩ
░ยᯕ a܆⦹݅(Fig. 4 ₙŁ). ᯕ۵ ʑ᳕᮹ MSPIෝ ⪽ᬊ⦹ᩍ
aྥᮥšญၰqෝᙹ⧪⦹۵ߑᯩᨕၽᔾ⦹۵ᱢᬊᔢ᮹⦽ĥᱱ
ᮥ ɚᅖ⦹ʑ ᭥⦽ ႊᦩᮝಽ DSPI᮹ ⪽ᬊᖒᮥ ᷾⧁ ᙹ ᯩ۵
⦹ӹ᮹ ~šᱢᯙ ɝÑಽ ❱݉ࡽ݅.
3. ROCᇥᕾᮥ☖⦽݉ʑaྥᰍ⩥܆ಆ⠪a
ᅙᩑǍᨱᕽ۵DSPI᮹aྥᰍ⩥܆ಆᮥᅕ݅~šᱢᮝಽ⠪a⦹
ʑ᭥⧕ᕽROC(Receiver Operating Characteristics) ᇥᕾᮥᙹ⧪
⦹ᩡ݅. ᯕ۵ ᬑญӹ ݡǭᩎᄥ ݉ʑaྥᮥ ⠪a⦹۵ ߑ ᯩᨕ
ŝÑᨱᝅᱽၽᔾ⦽aྥʑಾᮥʑၹᮝಽDSPI᮹aྥᰍ⩥܆ಆᮥ
⠪a⦹۵ äᯕ݅.
3.1 ROC ंজԹڄࢫࡦ෴ড୨
ROC ᇥᕾᮡ ᵝಽ ʑᔢᇥᨱᕽ ⪶ශᩩᅕ᮹ ᱶᖒᱢ á᷾ᨱ
⪽ᬊࡹ۵ʑჶᮝಽ, Kim and Lee (2011)۵ᝅᱽaྥᔍಡ᪡aྥ
ḡᙹ᪡᮹ ᱶపᱢᯙ ⠪aෝ ᭥⧕ ROC ᇥᕾᮥ ᱢᬊ⦽ ၵ ᯩ݅.
ᅙᩑǍᨱᕽ۵aྥḡᙹෝ⪽ᬊ⦽ᝅᱽaྥ᮹ᰍ⩥܆ಆᮥ⠪a⦹
ʑ᭥⧕ᕽTable 3ŝzᯕROC ༉⩶ᮥᖅᱶ⦹ᩡ݅. 2000֥ᯕ⬥ᨱ
ʑಾࡽaྥၽᔾ⩥⫊ᮥ᳑ᔍ⦹ᩍ“š⊂đŝ(Observed value)”ಽ
ᖅᱶ⦹Ł, ⧕ݚᱱᮥݡᔢᮝಽĥᔑࡽaྥḡᙹෝ“ᩩ⊂đŝ (Prediction value)”ಽᇥඹ⦹ᩍ“aྥ(ⷂ)”ŝ“aྥ(×)”ᨱ᮹⧕ᕽ
bb 2aḡᦊ ᇥඹ⦹ᩡ݅.
ᅙ ᩑǍᨱᕽ ᖅᱶ⦽ ༉⩶ᮡ ᝅᱽ aྥᯕ ၽᔾ⦽݅Ł ʑಾࡽ
Ğᬑᨱaྥḡᙹ(SPI)ᨱᕽࠥaྥᯕၽᔾ⧩݅Łӹ┡ӹ໕“ᖒŖ (Hit, H)”, ə౨ḡᦫ݅໕“༜ࡽĞŁ(Missing, M)”ಽӹ┡ԕᨩ
݅. ၹ໕, ᝅᱽᔍÕᯕၽᔾ⦹ḡᦫᮥĞᬑᩩ⊂đŝᨱᕽᔍÕᯕ
ၽᔾ⦽݅໕“ᝅ➉(False, F)”, ə౨ḡᦫ݅໕“ᮭ᮹ᖒŖ(Negative hit, N)”ᮝಽӹ┡ԕᨩ݅. ᯕᵲᖒŖ(H)ŝᮭ᮹ᖒŖ(N)᮹Ğᬑ۵
bbₙ᮹sᮝಽ❱݉⦹Ł, ᝅ➉᪡༜ࡽĞŁ۵ÑḴ᮹sᮝಽ
đᱶ⦽݅.
Table 3ŝ zᯕ ᇥඹࡽ 4aḡ᮹ Ǎᇥᮥ ☖⧕ Eqs. (3) and (4)ෝᯕᬊ⦹ᩍᱢᵲශ(Hit Rate, HR)ŝእᱢᵲශ(False Alram Rate, FAR)ᮥbbĥᔑ⦹໑, Fig. 5᪡zᮡROC ᳭⢽ĥԕᨱ
⦹ӹ᮹ᱱᮝಽ⢽⩥⧉ᮝಽ៉ROC łᖁᮥǍᖒ⧁ᙹᯩ݅. ROC s᮹ჵ᭥۵0ᨱᕽ1 ᔍᯕ᮹sᮥaḡ໑, łᖁᦥ௹᮹໕ᱢ(Area Under Curve, AUC)ᯕᔑᱶࡽ݅. ੱ⦽᪥ᄞ⦽ᩩ⊂ᯝভHR=1, FAR=0 ᯕအಽROC łᖁᯕ᳭⊂ᔢ݉ᨱaʭᯕ᭥⊹⧁ᙹಾaྥ
ḡᙹ᮹ ᰍ⩥܆ಆ ᬑᙹ⦹݅Ł ❱݉⧁ ᙹ ᯩ݅(Fawcett, 2006).
¡« á ¡îÞ¡ â¦ß
(3)« á îÞ â§ß
(4)3.2 ਓ୪րՋԧࢇ׆ߧுࢫۚ׆ԧࢇඌԧ
ROC ᇥᕾᮥᙹ⧪⦹ʑ᭥⧕ᕽ۵aྥḡᙹ᮹ᰍ⩥܆ಆᮥ❱݉⧕
ᵥɝÑෝᙹḲ⧕⦹໑, ᅙᩑǍᨱᕽ۵ᩍ్aḡaྥšಉᅕŁᕽ (aྥʑಾ᳑ᔍᅕŁᕽ(MLIT, 2001; 2005), ┽႒aྥ႒ᕽ(Tae Baek City, 2009)) ၰᨙುᅕࠥᯱഭ॒ᮥᙹḲ⦹ᩍ2000֥ᯕ⬥᮹
ɚ⦽݉ʑaྥ(2000֥(7Õ), 2001֥(45Õ), 2008֥(45Õ), 2009
֥(13Õ), 2012֥(3Õ)) ʑಾᮥ ᙹḲ⦹ᩡ݅. Table 4۵ ᙹḲࡽ
ᯱഭᵲ2009֥aྥᔢ⫊ᨱݡ⦽ᯱഭෝᩩಽᅕᩍᵡ݅. ੱ⦽
DSPIෝᯕᬊ⦽aྥᔢ┽᮹ᮁྕෝ❱݉⦹۵ߑʑᵡᯕࡹ۵ᱩ݉ᱱ
Table 4. The Collection of Previous Records for Extreme Drought in 2009
Year Area Starting date Finishing date Contents Duration(Day)
2009
Hongcheon 01-01 01-31 Rainfall(0.4mm) 31
Incheon 01-01 01-31 Rainfall(1.2mm) 31
Inje 01-01 01-31 Rainfall(1.7mm) 31
Taebaek 01-06 01-14 Restriction on water supply: 1,2 step
(3ton/day, Decrease 530%) 9 Taebaek 01-15 04-02 Restriction on water supply : 3step(3ton/day Decrease 50%) 87 The west coast of
Chungcheong 01-18 01-18 Daejun(8), Geumsan(7.5), Boryeong(7), Yesan(4), Cheonan(1.5) 1
Gangwon, Youngseo 03-03 03-03 Gangwon 13cm(Snow) 1
Korea south·central area 03-03 03-03 Heavy snow in Korea south·central area 1 Korea 03-20 03-21 Seoul(41.5), Jinju(100.5), Daegu(11.5), Chuncheon(40.5),
Taebaek(48.8), 2
Busan 08'12-03 01-07 Rainfall(9.5mm: 20% of rainfall compare to last year) 35
Busan 08'12-25 01-18 Drought warning 24
Table 5. Cut-off Value of ROC Curve Degree DSPI
Moderate Dry Severe Dry Extreme Dry
-1.49 to -1.00 -1.99 to -1.50 Less than -2.00
SPI_D30 SPI_D30(MD) SPI_D30(SD) SPI_D30(ED)
SPI_D60 SPI_D60(MD) SPI_D60(SD) SPI_D60(ED)
SPI_D90 SPI_D90(MD) SPI_D90(SD) SPI_D90(ED)
SPI_D120 SPI_D120(MD) SPI_D120(SD) SPI_D120(ED)
SPI_D150 SPI_D150(MD) SPI_D150(SD) SPI_D150(ED)
SPI_D180 SPI_D180(MD) SPI_D180(SD) SPI_D180(ED)
(cut-off value)ᮡTable 5᪡zᯕ3aḡaྥ॒ɪᮝಽđᱶ⦹ᩡ݅.
݅᧲⦽eࠥෝŁಅ⦽DSPI᮹ᱢᵲශ(Hit Rate, HR)ŝእᱢ ᵲශ(False Alram Rate, FAR)ᮥbbĥᔑ⦹Ł, ROC łᖁᦥ௹᮹
໕ᱢ(AUC)ᮥ ĥᔑ⦹ᩡ݅. Figs. 6(a), 6(b) and 6(c)۵ 3aḡ
aྥ᮹ ॒ɪᄥ aྥḡᙹ᮹ ᱢᵲශᮥ ӹ┡ԕ໑, b əฝ ᔢ݉ᨱ۵
baྥḡᙹ(SPI_D30, SPI_D60, SPI_D90, SPI_D120, SPI_D150, SPI_D180)ᨱݡ⦽bb᮹ᱢᵲශᯕ⢽ʑࡹᨕᯩŁFig. 6(d)۵
3aḡ aྥ ॒ɪᄥ AUCෝ ӹ┡ԙ݅.
ᯝၹᱢᮝಽROC łᖁᮡ᳭⊂ᔢ݉ᨱaʭᯕ᭥⊹⧁ᙹಾ, ੱ۵
ᱢᵲශsᯕ1.0ᨱaʭᬙᙹಾaྥḡᙹ᮹ᰍ⩥܆ಆᬑᙹ⦹݅Ł
⧕ᕾࡽ݅. ᅙᩑǍᨱᕽ۵ᅕ☖aྥᨱᕽ۵ᱢᵲශ0.76ŝ0.74ಽ
⪶ᯙࡹ۵SPI_D30᪡SPI_D150, ᝍ⦽aྥᨱᕽ۵ᱢᵲශ0.83ŝ
0.81ಽ⪶ᯙࡹ۵SPI_D90ŝSPI_D60, ɚ⦽aྥᨱᕽ۵ᱢᵲශ
0.68ಽ⪶ᯙࡹ۵SPI_D30aDSPIෝᯕᬊ⦹ᩍaྥᮥᰍ⩥⦹۵
ߑ ᯩᨕ ᅕ݅ ⬉ᮉᱢᯙ äᮝಽ ❱݉ࡽ݅.
ᯕౝ, ᝅᱽ݉ʑaྥ᮹⠪aෝ༊ᱢᮝಽ⦽݅໕, ʑ᳕ᨱ3}ᬵ
ᯕ࠺⠪Ɂvᙹపᮥʑၹᮝಽᔑᱶ⦽SPI_M3ŝᇩᨕSPI_D30
᪡ SPI_D60ŝ zᮡ ᅕ݅ Ṉᮡ ʑe᮹ ٥ᱢvᙹపᮥ ᯕᬊ⦹ᩍ
ĥᔑࡽDSPIෝ⇵aಽá☁⧁⦥aᯩ݅. ၹ໕, ᩩᅕ᮹ᱢᵲශᯕ
ԏíӹ┡ӽaྥḡᙹෝᯕᬊ⦹ᩍ݉ʑaྥᮥ ⠪a⧁Ğᬑᨱ۵
ᔢݡᱢᮝಽaྥ❱݉᮹ᝁࠥaᱡ⦹ࢁa܆ᖒᯕᯩᮝအಽ, ݉ʑ aྥ ⠪aෝ ᭥⧕ aྥḡᙹෝ ᖁᱶ⧁ Ğᬑᨱ۵ ᖙᝍ⦽ ᵝ᮹a
⦥⦹݅.
3.3 କตԧࢇ(EDI)ࠜଲDSPIଭୡনඌԧ
ᦿᱩᨱᕽᔑᱶ⦽DSPI᮹ᱢᬊᖒᮥá☁⦹ʑ᭥⧕ᕽʑ᳕ᨱ}ၽࡽ aྥḡᙹ ᵲ ᮁᯝ⦽ ᯝ ݉᭥ aྥḡᙹᯙ ᮁ⬉aྥḡᙹ (Effective Drought Index, EDI)᪡እƱ⦹ᩡ݅. Byun and Wilhite (1999)ᨱ໕, ᯝၹᱢᮝಽEDI۵✚ᱶᯝ᮹“ᮁ⬉٥ᱢvᙹప (EP)”ᮥ ĥᔑ⦽ ⬥, ə ԁ᮹ ʑ⬥ ⠪Ɂᯙ “ᮁ⬉vᙹvᙹప”ŝ
እƱ⦹ᩍᇡ᳒ప⪚ᮡⅩŝపᮥĥᔑ⦽⬥ᯕෝ⢽ᵡ⪵⦽݅. ᩍʑᕽ,
“ᮁ⬉٥ᱢvᙹప”ᯕ ᯕᱥ 365ᯝ(⪚ᮡ ə ᯕᔢ) ࠺ᦩ ٥ᱢࡽ
(a) Moderate Dry (MD) (b) Severe Dry (SD)
(c) Extreme Dry (ED) (d) AUC for Each Degree of Dryness Fig. 6. The results of ROC Analysis (HR, FAR, AUC)
Table 6. The Results of ROC Score for Daily SPI and EDI in 9 Regions Degree
Region
Moderate Dry(MD) Severe Dry(SD) Extreme Dry(ED) SPI_D30 SPI_D60 SPI_D90 EDI SPI_D30 SPI_D60 SPI_D90 EDI SPI_D30 SPI_D60 SPI_D90 EDI South Korea 0.761 0.723 0.530 0.663 0.729 0.807 0.825 0.648 0.622 0.546 0.578 0.496 Gangwon Youngdong 0.589 0.559 0.532 0.531 0.812 0.674 0.689 0.571 0.618 0.588 0.522 0.479 Gangwon Youngseo 0.621 0.516 0.577 0.581 0.656 0.519 0.506 0.498 0.660 0.541 0.593 0.512 Seoul Gyeonggi 0.621 0.512 0.531 0.502 0.576 0.511 0.620 0.507 0.601 0.582 0.588 0.502 Chungcheongbukdo 0.653 0.516 0.443 0.453 0.574 0.498 0.667 0.449 0.857 0.727 0.654 0.887 Chungcheongnamdo 0.925 0.699 0.707 0.571 0.876 0.893 0.767 0.977 0.947 0.886 0.775 1.000 Gyeongsangbukdo 0.837 0.590 0.646 0.492 0.842 0.794 0.710 0.408 1.000 0.966 0.855 0.886 Gyeongsangnamdo 0.606 0.539 0.524 0.581 0.748 0.630 0.503 0.465 0.797 0.649 0.582 0.491 Jeollabukdo 0.680 0.556 0.528 0.577 0.838 0.547 0.521 0.459 0.746 0.775 0.566 0.490 Jeollanamdo 0.745 0.775 0.567 0.724 0.764 0.825 0.820 0.685 0.589 0.508 0.551 0.488
vᙹపᯕ໑, 365ᯝ࠺ᦩvᙹప⧊ᔑᮥǍ⧁ভ᪅௹ᱥvᙹపᮡ
ᯕၙฯᯕᗭᝅࡹᨩᮭᮥaᵲᯙᯱෝ☖⧕ၹᩢ⦹Ł࠺ᨱ↽ɝ
vᙹపᮡฯᮡᇡᇥԉᦥᯩᮭᮥŁಅ⦹ᩍ}ၽࡽaྥḡᙹᯕ݅.
ᅙᩑǍᨱᕽ۵ᇡĞݡ⦺ƱႊᰍʑᔢᩑǍᝅ(http://atmos.pknu.
ac.kr/~mdr/)ᨱᕽᱽŖ⦹۵EDI ĥᔑᗭ⥥✙ᭉᨕෝ⪽ᬊ⦹ᩡᮝ໑, SPI_D30, SPI_D60, SPI_D90ŝ ⧪ᱶǍᩎᄥ EDIෝ ⪽ᬊ⦹ᩍ
ᬑญӹ2000֥ᯕ⬥ᨱၽᔾ⦽ɚ⦽݉ʑaྥ(2000֥, 2001֥, 2008֥, 2009֥, 2012֥) ʑಾᮥၵ┶ᮝಽROC ᇥᕾᮥᙹ⧪⦹ᩡ
݅. ə đŝ ᱥǎᱢᮝಽ۵ ᅕ☖ aྥ(MD)ᮥ ᰍ⩥⧁ Ğᬑᨱ۵
SPI_D30᮹ᱢᵲශ(0.761)ᯕ׳íӹ┡ԍᮝ໑, ၹ໕SPI_D90᮹
ᱢᵲශ(0.530)ᯕaᰆԏᮡäᮝಽ⪶ᯙࡹᨩ݅. ੱ⦽ᝍ⦽aྥ
(SD)ᨱᕽ۵SPI_D90᮹ᱢᵲශ(0.825)ᯕaᰆ׳ŁEDI᮹ᱢᵲශ (0.648)ᮡ aᰆ ԏᦹᮝ໑, ɚᝍ⦽ aྥ(ED)ᨱᕽ۵ SPI_D30᮹
ᱢᵲශ(0.622)ᯕ aᰆ ׳Ł EDI᮹ ᱢᵲශ(0.496)ᮡ aᰆ ԏᮡ
äᮝಽ ⪶ᯙࡹᨩ݅(Table 6 ₙŁ).
4. đು
ᅙᩑǍᨱᕽ۵ᬑญӹ᮹⧪ᱶǍᩎᮥ9}᮹ݡǭᩎᮝಽǍᇥ⦹
ᩍʑᔢ⦺ᱢaྥ᮹}ֱᮥᱢᬊ⦹ᩍ, ʑ᳕᮹ᬵ݉᭥ʑၹᮝಽ
ĥᔑࡹᨕḥSPIᨱݡ⦽ᱢᬊᔢ᮹⦽ĥෝɚᅖ⧁ᙹᯩ۵ݡᦩᮝಽ
ᯝ݉᭥SPIෝᱽᦩ⦹ᩡ݅. ੱ⦽6}ᬵၙอ᮹݉ʑaྥᮥ⠪a⧁
Ğᬑᯝ݉᭥SPI᮹⦥ᖒၰ⪽ᬊࠥෝ~šᱢᮝಽá☁⦹Łᯱ, ᝅᱽ ŝÑᨱ ၽᔾ⦽ aྥᔍಡෝ ᙹḲ⦹ᩍ እƱ·ᇥᕾ⦹ᩡ݅. ə
đŝ, ݉ʑᱢᯙ⊂໕ᨱᕽʑ᳕᮹ᬵ݉᭥ʑၹ᮹aྥḡᙹෝᯕᬊ⦹
ᩍaྥᮥ❱݉⧁Ğᬑᨱၽᔾa܆⦽ᱢᬊᔢ᮹⦽ĥෝᅙᩑǍᨱᕽ
ᱽᦩ⦽ᯝ݉᭥SPIෝ⪽ᬊ⦹ᩍɚᅖᯕa܆⦹ᩡ݅. ᯕ۵ᝅᱽಽ
ၽᔾ⦽aྥᔍᔢ᮹ḥ⧪ ᱶࠥෝᩑᗮᱢᮝಽᯝᄥ༉ܩ░ย⦹ᩍ
aྥᮥqḡ⦽⬥, aྥᯕ⧕iࡹ۵ᱥŝᱶᮥᯝ݉᭥ಽq⧁
ᙹ ᯩí ࡹᨩ݅.
ᇩᨕᯝ݉᭥SPI᮹┡ݚᖒᮥá☁⦹ʑ᭥⧕ᕽ2000֥ᯕ⬥ᨱ
ၽᔾ⦽ ŝÑ aྥʑಾᮥ ᙹḲ⦽ ⬥, ᯕෝ ʑၹᮝಽ ᬑญӹ᮹
ݡǭᩎᄥ ݉ʑaྥᨱ ݡ⦹ᩍ ݅᧲⦽ eࠥᨱ ෙ ᯝ ݉᭥
SPI᮹aྥᰍ⩥܆ಆᮥ⠪a⦹ᩡ݅. ᅙᩑǍᨱᕽ۵ROC ༉⩶ᮥ
⪽ᬊ⦹ᩍaྥᰍ⩥᮹ᱢᵲශᮥĥᔑ⦹ᩡᮝ໑, əđŝaྥၽᔾ᮹
ᮁྕෝđᱶ⦹۵ᱩ݉ᱱ᮹ᄡ⪵ᨱaྥᮥᰍ⩥⦹۵ߑᯩᨕ
⬉ᮉᖒᯕ׳ᮡSPI᮹eࠥෝၽč⧁ᙹᯩᨩ݅. ᷪ, ᯝ݉᭥
SPIෝ⪽ᬊ⦹ᩍ6}ᬵၙอ᮹݉ʑaྥᮥ⠪a⧁Ğᬑ, ໑⋁࠺ᦩ᮹
٥ᱢvᙹపᮥ Łಅ⦹ᩍ ĥᔑࡹᨕḥ ᯝ ݉᭥ SPIෝ ᅖ⧊ᱢᮝಽ
⪽ᬊ⧕ᝅᱽၽᔾ⦹۵aྥᮥḥ݉⧉ᨱᯩᨕᝁᖒᮥ⨆ᔢ┍
ᙹ ᯩ۵aᨱ ݡ⦽ ❱݉ᯕ a܆⧕ ḥ݅.
✚⯩, ݅᧲⦽eࠥᨱෙᯝ݉᭥SPI ᵲᨱᕽSPI_D30,
SPI_D60, SPI_D90 ॒᮹ᙽᕽಽɚ⦽aྥᨱݡ⦽ᰍ⩥܆ಆᯕ
ᬑᙹ⦽äᮝಽ⪶ᯙࡹᨩ݅. ᩍʑᕽɚ⦽aྥᮡ30ᯝ, 60ᯝ, 90ᯝŝ
zᯕݡᇡᇥ3}ᬵၙอ᮹e࠺ᦩᨱ٥ᱢࡽvᙹపᯕ⠪֥᮹
ᙹᵡŝእƱ⦹ᩍⓍíᇡ᳒⧉ᮝಽᯙ⧕ၽᔾ⦽aྥᯕŁ⧕ᕾࡹ
ᨕḥ݅. ݅ั⧕, ʑ᳕᮹3}ᬵ, 6}ᬵ॒᮹٥ᱢvᙹపᮥʑၹᮝ ಽᔑᱶࡽᬵ݉᭥SPIෝᯕᬊ⦹ᩍᝅᱽ݉ʑᱢᯙvᙹᇡ᳒ᮝಽ
ᯙ⧕ၽᔾ⦽aྥᮥḥ݉⦹Ł⠪a⦹۵ߑᨱ۵ᝅḩᱢᯙ⦽ĥᱱᯕ
ᯩ۵ äᮝಽ ❱݉ࡽ݅.
đುᱢᮝಽᯝ݉᭥SPIෝʑၹᮝಽḡᗮᱢᯙaྥ༉ܩ░ยᮥ
☖⧕aྥ᮹ᱶࠥෝᅕ݅⬉ŝᱢᮝಽ⢽⩥⧕ᵥᙹᯩ۵٥ᱢvᙹᯝ ᙹෝᔍᱥᨱຝᱡđᱶ⦽⬥, ᯕෝʑၹᮝಽĥᔑ⦽aྥḡᙹෝ
ᖁᱶ⦹ᩍ ⪽ᬊ⧕ ⦽݅. ੱ⦽ ၙ௹ aྥᰍ⧕ෝ ݡእ⦹ʑ ᭥⦽
ႊᦩᮝಽɚ⦽aྥၽᔾၰᰆʑᱢᮝಽḡᗮࡹ۵aྥᮥq⦹Ł
šญ⦹ʑ᭥⧕ᕽ۵ᯝ݉᭥aྥḡᙹෝ ⪽ᬊ⦽aྥ༉ܩ░ยᮡ
⦥ᙹᱢᯝ äᯕŁ ❱݉ࡽ݅.
qᔍ᮹ɡ
ᅙ ᩑǍ۵ ᗭႊႊᰍℎ᮹ ᯱᩑᰍ⧕ᱡqʑᚁ}ၽᔍᨦ[NEMA-
ᯱᩑ-2011-40] ḡᬱᮝಽ ᙹ⧪ࡹᨩܩ݅. ᯕᨱ qᔍऽพܩ݅.
