Estimation of Perceived Flood Damage in Tokyo Metropolitan Area

Transcription

1 Estmaton of Perceved Flood Damage n Tokyo Metropoltan Area Azusa OKAGAWA* Akra HIBIKI* * Natonal Insttute for Envronmental Studes

2 Overvew Comparng prces of lands wth/wthout flood rsk Land prce wthout flood rsk γ Land prce wth flood rsk LP α β n Atrbute n, γ n FloodRsk u Unobservable varables Perceved flood rsk mght correlate wth unobservable determnant of land prces. => Two stage estmaton wth nstrumental varables 2

3 Background Clmate change wll brng an ncrease n frequency and severty of flood. Current flood control polcy has been mplemented based on the plan n absence of perspectve on adaptaton to clmate change. The measure of cost and beneft should be examned wth the perspectve on adaptaton. 3

4 The heavy ranfall havng 100 year recurrence nterval Toka heavy ran dsaster, September % of cty area was flooded n Nagoya Nagoya s a central cty of Toka area wth populaton of 2 mllon. The flood caused by overflow banks. Most of recent floods n urban area are nland floodng. Somewater overflowed Nagoya s10 dkes. Tokyo metropoltan govt prepared flood hazard map. Osaka Nagoya Tokyo Cars under water* * Cabnet offce < > Overflow water* (Nsh Bwajma) Waste due to flood* 4

5 Prevous studes Flood rsk > Reducton of land prce Hallstrom and Smth (2005) Bn and Polasky (2004) There exst many studes on flood damage by hedonc approach n Japan Problem of prevous studes Estmaton bas caused by omtted varables 5

6 Flood rsk varable Flood hazard map Issued by the Tokyo Metropoltan Govt Ths hazard maps based ontheresult offloodsmulatonflood onthe assumpton ofthe equvalent heavy ran to the Toka Flood Dsaster whch s expected to occur once every 100 year. Flood rsk varable: If the ste s ncluded n hazard area, DRsk = 1otherwse DRsk = 0 6

7 Problem of prevous studes Hedonc Land Prce model Land Prce Attrbutes Flood rsk dummy lnlp = α + X β + γdrsk + Attrbute varables: bl Unobservable bl varables bl Bulk rato, elevaton, Tme dstance to termnal statons, 23specal wards dummy, Ralwaylnedummy lne dummy, etc. Omtted varables brng estmaton bas on gamma and flood rsk mpact on land prce cannot be dentfed. p lmγˆ γ Cov( FloodRsk, OmttedVarables) Var ( FloodRsk) Two stage procedure u γ 7

8 Two stage estmaton Flood Hazard model Rsk PRsk δ Y θ e Flood factors: DsRver, Hollow, 23 specal lwards dummy, etc. 1 φ( δˆ θˆ) Y Predcted probablty Hd Hedonc Land dp Prce model dl DRsk ln LP α X β γ PRsk u 8

9 Instrumental varables Hollow mn( Elevaton n, ) Elevaton If the ste s lowest, the water cannot run off. Flood rsk could be hgher. Elev 1 Elev 2 Elev 3 Elev 4 Elev Elev 5 Hollow Hollow 0 0 f the ste s lowest otherwse 50m Elev 6 Elev 7 Elev 8 DsRver 50m : Dstance to the nearest rver If the ste s close to rvers, flood rsk could be hgher. 9

10 Coverage area and data Coverage area Tokyo 19 specal wards Excludng Katsushka, Shbuya, Aarakawa, Sumda The flood hazard map Publshed by the Tokyo Metropoltan Government Flood Rsk Dummy If the ste s located n the area explored by flood, DRsk = 1 Offcal Land Prce Reported by Mnstry of Land, Infrastructure, Transport and Toursm n 2009 Land prce, land shape, land use zonng, accessblty to the gas, water and sewerage utltes, the name of the nearest staton, the dstance from t, lot percentage regulaton, bulk rato regulaton, etc. Yahoo! route search Accessblty to termnal statons of JR Yamanote lne. 10

11 Man estmaton result Flood Hazard model Coef Std. error Intercept DsRver *** Hollow ** Predected flood rsk PRsk 11

12 Man estmaton result 1 Hedonc land prce model Model 1 OLS estmaton 2-stage estmaton Coef Std err Coef Std err Constant *** *** Flood rsk * *** Bulk rato X Flood rsk Buldng coverage rate X Flood rsk Heght X Flood rsk Elevaton 0.008*** 008*** *** 007*** Area (m 2 ) 0.000*** *** Dstance from Staton *** *** Tme dstance to termnal staton *** *** Inner Yamanote lne 0.131*** *** Bulk rato 0.003*** *** Resdental area 1 dummy *** *** Resdental area 2 dummy *** *** Industral area dummy *** *** Adj R squared Endogenety test 採 択 Over dentfcaton test 採 択 Reducton of land prce (%) OLS: 3.4% 2 stage: 14.5% 12

13 Man estmaton result 2 Hedonc land prce model Model 2 OLS estmaton 2-stage estmaton Coef Std err Coef Std err Constant *** *** Flood rsk ** Bulk rato X Flood rsk ** *** Buldng coverage rate X Flood rsk Heght X Flood rsk Elevaton 0.008*** 008*** *** 007*** Area (m 2 ) 0.000*** *** Dstance from Staton *** *** Tme dstance to termnal staton *** *** Inner Yamanote lne 0.130*** *** Bulk rato 0.003*** *** Resdental area 1 dummy *** *** Resdental area 2 dummy *** *** Industral area dummy *** *** Adj R squared Endogenety test 採 択 Over dentfcaton test 採 択 Reducton of land prce (%) OLS: 3.5% 2 stage: 16.0% 13

14 Man estmaton result 3 Hedonc land prce model Model 3 OLS estmaton 2-stage estmaton Coef Std err Coef Std err Constant *** *** Flood rsk 0.489*** *** Bulk rato X Flood rsk Buldng coverage rate X Flood rsk *** *** Heght X Flood rsk *** Elevaton 0.008*** 008*** *** 007*** Area (m 2 ) 0.000*** *** Dstance from Staton *** *** Tme dstance to termnal staton *** *** Inner Yamanote lne 0.132*** ** Bulk rato 0.003*** *** Resdental area 1 dummy *** *** Resdental area 2 dummy *** *** Industral area dummy *** *** Adj R squared Endogenety test 採 択 Over dentfcaton test 採 択 Reducton of land prce (%) OLS: 3.7% 2 stage: 18.2% 14

15 Dscusson d Reducton rate of LP LP w LP w o Rsk / Rsk ( e 0 1) (%) / 157 Reducton n Land Prce: 169,438 yen/m 2 (1,631 EUR) Reducton 0.01 n LP 100 d(1 d) (1 ρ) t 0 99 t D 169,483 yen / m : occurrence probablty ρ : dscount rate 13,552 EUR/m 2 Average flood damage D = 1,408, yen/m 2 Not only physcal damage, but also ndrect damage such as loss of lfe, loss of proft, mentaldamage,etc. etc. 2 The Govt estmaton D = 33,199 yen/m 2 Only physcal damage 15

16 Concluson We estmated Hedonc Land Prce model by two stage estmaton to correct the bas caused by omtted varables. The reducton rate of land prce n hazardous area s 14.5% and the perceved flood damage s 1,408,049 yen/m 2 (13,552 EUR/m 2 ). Our estmate s much hgher than that of the Tokyo Metropoltan Government snce our estmate nclude not only physcal damage, but also ndrect damage such as opportunty proft and mental damage. Contact address: okagawa.azusa@nes.go.jp 16