10(1)-05(서희철).fm

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1 w» wz, 10«1y(2008) Korean Journal of Agricultural and Forest Meteorology, Vol. 10, No. 1, (2008), pp. 25~31 v» y ( ) š» s 1 Á 2 Á 1 * 1 w k lœw, 2 ù ( ; ) Azimuthal Distribution of Daily Maximum Temperatures Observed at Sideslopes of a Grass-covered Inactive Parasitic Volcano ( Ohreum ) in Jeju Island Hee-Chul Seo 1, Seung-Jong Jeon 2 and Jin I. Yun 1 * 1 Department of Ecosystem Engineering, Kyung Hee University 2 National Institute of Subtropical Agriculture, Rural Development Administration (Received February 12, 2008; Accepted March 24, 2008) ABSTRACT Information on daily maximum air temperature is important in predicting the status of plants and insects, but the uneven and sparse distribution of weather stations prohibits timely access to the data in regions with complex topography. Since cumulative solar irradiance plays a critical role in determining daily maximum temperature on any sloping surfaces, derivation of a quantitative relationship between cumulative solar irradiance and the resultant daily maximum temperature is a prerequisite to development of such estimation models. Air temperatures at 8 sideslope locations with similar elevation and slope angle but aspect, circumventing a cone-shaped, grass-covered parasitic volcano (c.a., 570G m diameter for the bottom circle and 90m bottom-to-top height), were measured from June to December in Daily maximum temperatures from each location were compared with the average of 8 locations (assumed to be the temperature measured at a horizontal reference position). The temperature deviation at all locations increased with the day of year (or sun elevation) from summer solstice to winter solstice. Averaged over the entire period, the south facing location was warmer by 1 o C in daily maximum temperature than horizontal reference and the north facing location was cooler by 0.8 o C than the reference, resulting in the year round average south-north temperature difference of 1.8 o C. In November, both south and north facing slopes showed the greatest deviation of +2.0 o C and -1.3 o C, respectively in daily maximum temperature at monthly scale. On a daily scale, the greatest deviation was +3.8 and 2.7 o C at the south and north slope, respectively. The cumulative solar irradiance (on the slope for 4 hours from 11:00 to 15:00 TST) explained >60% of the variance in daily maximum temperature deviations among 8 locations, suggesting a feasibility of developing an estimation model for daily maximum temperature over complex topography at landscape scales. Key words : Daily maximum temperature, Solar radiation, Geospatial climatology, Topography I. Ÿw y,, s- - w» w ƒ. ù», y, ƒƒ p,» m ù x, y y Corresponding Author : Jin I. Yun (jiyun@khu.ac.kr)

2 26 Korean Journal of Agricultural and Forest Meteorology, Vol. 10, No. 1 mw ù, k, y w. k ƒ w w wù y ƒ k e w e x txwš ³ (landscape scales) y w (Bolstad et al., 1998). k x w ƒ w wùƒ»» œ šw» s w w. ù» d ƒ û» d w ³ šw» s w (Running et al., 1987; Yun, 2004). k x» ( š» ) w š, p» 10~30m w x w¾ š w» w (Yun, 2007).»» w» s w w z (Choi et al., 2003), þƒ w x œ» ù z (Chung et al., 2006) œ» k œ»z» j» w. w š» w w p x w š w» w e w q (Regniere, 1996).» w w w x w w txw, û w š» Ÿ w j ƒƒ yw k e» ww ùkù Ÿ, š Ÿ š» xyw ƒ w. x š» s ü» w w» sƒ» ( s d ) t d œ r q w w.» d š, tv d ( ) w. x» x œ» š»» ù w š. w x w» y wš ƒ wù w» d w š»»» y wš w. š 2007 w l ¾ m š» s p s» wš, w p Ÿ r q w. II x w š»» w x ww» w tƒ š, w x w w» y ( ) x w (Fig. 1).» y x w 570m Õ ( )¾ š s³ 90m. l 70m w» y d 8 w t l 1.5m» x (Model HOBO H8 Pro, Onset Computer Co., USA) ew. x ùe w e ew z d (Model GeoExplorer III Pathfinder 2.80, Trimble Inc., USA) w t š, z» w z w yw e t. ƒ l 10» d w š, d 144 ƒ ƒ j š» w. x s d w» w» y v x (Model 8-48, Eppley Laboratory Inc., USA) ewš,»(model CR10X, Campbell Scientific, USA) w 1 d w w (w ) l ( )¾

3 Seo.: Azimuthal Distribution of Daily Maximum Temperatures Observed at Sideslopes... et al 27 Location map of the study area with the synoptic weather station in Jeju Island (top left), a satellite image of the parasitic volcano (top right), locations of 8 temperature stations and 1 solar radiation station on the elevation map of the volcano (bottom left), and a photo image of one temperature station installed at the volcano (bottom right). Fig 일간 관측된 8개 지점의 일 최고기온자료를 수집하 였다. 수집된 8개 지점의 기온을 산술평균하여 같은 고도의 기준온도(수평면 일 최고기온)로 간주하였다. 각 지점에서 얻은 일 최고기온에서 이 기준온도를 감 하여 편차를 계산하였다. 국토지리정보원으로부터 실험장소가 포함된 1:5,000 수치지형도(도엽번호 )를 사용하여 주곡선 정 보로부터 TIN(triangulated irregular network) 표면을 생성하고, 해상도 1m의 DEM(digital elevation model) 으로 변환하였다. 이 DEM으로부터 경사도와 경사방향 을 계산하였고, 8개 지점에 해당하는 픽셀의 경사향과 경사도자료를 추출하였다. 이들 지형자료와 기준점(정 상 부근)의 전천일사량자료를 토대로 각 지점의 시간 대별 일사수광량을 계산하였다. III. 결과 및 고찰 일 최고기온의 월별 평균 추세 관측기간 중 태풍피해를 입은 S1과 S7을 제외한 나머지 지점에서는 결측 없이 온전한 자료를 수집할 수 있었다. 1m DEM에 의해 계산된 8개 지점의 경 사도는 20도(S3)부터 30도(S5)까지 범위에 들며 평균 은 26도 정도이다. 경사향은 S1과 S8이 거의 같은 북향이며 나머지는 동(S2), 남동(S3), 정남(S4), 남서 (S5), 정서(S6), 북서(S7)에 분포하고 있다(Table 1). 태양고도가 가장 높은 하지부터 가장 낮은 동지까지 8개 지점에서 관측된 일 최고기온이 8개 지점의 평균 인 기준온도에 비해 얼마나 차이가 나는지 그 편차를 구해 월별로 평균한 결과, 북향에 속하는 S1과 S8에 3.1.

4 28 Korean Journal of Agricultural and Forest Meteorology, Vol. 10, No. 1 Table 1. Slope and aspect of 8 observation sites and the observed daily maximum temperature deviations from the reference (mean of 8 sites) SITE # Slope (degree) Slope aspect (degree) Temperature Deviation ( o C) Jul. Aug. Sep. Oct. Nov. Dec » üü» w û. ƒ j r 11 S o C, S o C. ûw S4 S5» w š», r o C(S4), 1.63 o C(S5). w (S6) ys j 7, 8, 9» w š» š 10, 11, 12» û». e e S7 w w» r s» û ƒ ùkù»ƒ 9. w w S2 S3 ƒ e e S2 w» û š» š, û ƒ¾ S3 7, 8, 9, 10 ¾»» ƒ 11, o C» d. w ¾ 183 s³r w» w š» ƒ œ S4( û w) 1.02 o C š, ƒ û œ S1( w) d yw r. ƒ¾ ew S8 s³r ƒ 0.72 C û» o. û w š» r s³ 1.7~1.8 C o, q e ûw w d s³ 1.4 o C r j (Bolstad et al., 1998).» y 20~30 q e x 21~31 w, (33.5N) q e x (35~36N) û w 1.8 C o û š» r s³ w. x v w š» ƒ j ƒ ew š. Fig. 2. Deviations in daily maximum temperature at 8 locations compared with a reference observed from summer solstice to winter solstice in Thick lines indicate the 45 daymoving average. Approximate aspect for each site is: 1=N, 2=NE, 3=SE, 4=S, 5=SW, 6=W, 7=NW, and 8=N.

5 Seo et al.: Azimuthal Distribution of Daily Maximum Temperatures Observed at Sideslopes š» ƒ š» r w l ¾ ú w w s» w w š» e w ww, w w w z w ƒ š f š (Fig. 2). ûw S4 d» š»» w 4 o C¾, w S1 S8» w { û š» r 3 o C w. 45 s³ w k š (ú ) š» ƒ w. w w w k š Ÿ» j ƒ» j š» ùkù. k š ƒ û w Ÿ ƒ»» w š» ûw d (S4, S5) w (S1, S8) û š. ù w w d s j š» r» w 2 o C w Ÿ š» x l Ÿ ƒ š» ùkù y w. Ÿ š», t w ƒ ª š» w w x ë y w t d w ƒ w. x k w tv m š, d w, tš w m»»,, m, ƒ d ƒ š» t q w ù ƒ ( ) x y» x» yw». ù» Ÿ x q wš w. š» z w ƒ t w z w j w e. Regniere (1996) w k û 1, û z 3 w 4 w š» d s r w š» w. x Regniere(1996)ƒ w (1) w 8 Ÿ r wš d š» r w. ϕ max υ ϕ ϕ t 0 = (1) υ (overheating index), 4 s Ÿ (ϕ 0 ) Ÿ (ϕ t ) t yw. t y d s z 4 Ÿ r ƒ (15 MJ m ) 3 78 û 2 45 ùkù. x 1m DEM» w,» y d m Chung et al.(2007) w 2007 w l ¾ w. Fig. 3 ƒ ƒ S4(ûw) S8 ( w) w txw.» w Ÿ š, s w. d kt w d ƒ q Fig. 3. Seasonal march of the calculated values for daily overheating index (OHI) at south- and north-facing slopes.

6 30 Korean Journal of Agricultural and Forest Meteorology, Vol. 10, No. 1». p ƒ w s j ù ûw. w ûw k š ƒ û» (0) l w w» ƒ¾ š. d š» r w ûw y», w š» r w. Regniere(1996)ƒ w š» w š w, ûw w, w w. ƒ š» r w Fig. 4. wû 4 Ÿ s w j (, ƒ ), w l ¾ š»» r 0.8. l w 1 z w l š» w. ú v ƒ 0.1 ú š» s» w 2 o C ƒ w Fig. 4. Relationship between daily overheating index (OHI) and deviation in daily maximum temperature at the locations on south-facing slopes of the grass-covered volcano from June to December w ú m,,, š w š w, 0.64» r 64% w». wz m,, mw w f. Regniere et al.(1996) w w» r (ε) w ú ú w yw» w»» w w (2) txw. ε = υ R T R (2)» R», T R s Ÿ r w» w, 1 o C» txw (2) eù w k x(biosim) š», ƒ 10 o C ú ƒ 0.1 s w š» 0.14 o C w. v ¼ wù x» r { j. x z»» 23.2 (2) R T R w w. 10~20 ƒ w v 1 o C š» w 1.16~ y w w. x w» š w, e ù w w v vw ƒ w j. w w Ÿ œ š» y w v { j. x x» y ( ) w x» d w», m» t ƒ w tv w ƒ w ƒ x. v Ÿ ƒ

7 Seo et al.: Azimuthal Distribution of Daily Maximum Temperatures Observed at Sideslopes š» e w q w» w 2007 w l ¾ 570m, 90m x» y d 8 š» d w. 8 s³» w ƒ» r w w» r w l f w š, d» s³ ûw 1.0 o C, w 0.8 C ƒ s³ o 1.8 C o w.» r s³ 11 ƒ j ûw 2.1 o C, w 1.3 o C.» r ûw 3.8 o C, w 2.7 C o w, w» r Ÿ r w xp x š» x y». x v w ( ) œw w Ì.». REFERENCES Bolstad, P. V., L. Swift, F. Collins, and J. Regniere, 1998: Measured and predicted air temperatures at basin to regional scales in the southern Appalachian mountains. Agricultural and Forest Meteorology 91, Choi, J., U. Chung, and J. I. Yun, 2003: Urban-effect correction to improve accuracy of spatially interpolated temperature estimates in Korea. Journal of Applied Meteorology 42 (12), Chung, U., H. H. Seo, K. H. Hwang, B. S. Hwang, J. Choi, J. T. Lee, and J. I. Yun, 2006: Minimum temperature mapping over complex terrain by estimating cold air accumulation potential. Agricultural and Forest Meteorology 137, Chung, U., K. H. LeeGand J. I. Yun, 2007: Performance of Northern Exposure Index in reducing estimation error for daily maximum temperature over a rugged terrain. Korean Journal of Agricultural and Forest Meteorology 9, (in Korean with English abstract) Regniere, J., 1996: A generalized approach to landscape-wide seasonal forecasting with temperature-driven simulation models. Environmental Entomology 25, Regniere, J., B. Cooke, and V. Bergeron, 1996: BioSIM: A Computer-Based Decision Support Tool for Seasonal Planning of Pest Management Activities. User's Manual. Canadian Forest Service Info. Rep. LAU-X pp. Running, S. W., R. R. Nemani, and R. D. Hungerford, 1987: Extrapolation of synoptic meteorological data in mountainous terrain and its use for simulating forest evaporation and photosynthesis. Canadian Journal of Forest Research 17, Yun, J. I., 2004: Visualization of local climates based on geospatial climatology. Korean Journal of Agricultural and Forest Meteorology 6, (in Korean with English abstract) Yun, J. I., 2007: Applications of High Definition Digital Climate Maps in restructuring of Korean agriculture. Korean Journal of Agricultural and Forest Meteorology 9, (in Korean with English abstract)