• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.4
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• pp.281-289
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• 2015

Information on sunshine duration and solar radiation are indispensable to the understanding of crop growth and development. Yet, relevant variables are not available in the Korea Meteorological Administration's (KMA) digital forecast. We proposed the methods of estimating sunshine duration and solar radiation based on the 'sky condition' of digital forecast products and validated using the observed data. The sky condition values (1 for clear, 2 for partly cloudy, 3 for cloudy, and 4 for overcast) were collected from 22 weather stations at 3-hourly intervals from August 2013 to July 2015. According to the observed relationship, these data were converted to the corresponding amount of clouds on the 0 to 10 scale (0 for clear, 4 for partly cloudy, 7 for cloudy, and 10 for overcast). An equation for the cloud amount-sunshine duration conversion was derived from the 3-year observation data at three weather stations with the highest clear day sunshine ratio (i.e., Daegwallyeong, Bukgangneung, and Busan). Then, the estimated sunshine hour data were used to run the Angstrom-Prescott model which was parameterized with the long-term KMA observations, resulting in daily solar radiation for the three weather stations. Comparison of the estimated sunshine duration and solar radiation with the observed at those three stations showed that the root mean square error ranged from 1.5 to 1.7 hours for sunshine duration and from 2.5 to $3.0MJ\;m^{-2}\;day^{-1}$ for solar radiation, respectively.

• Korean Journal of Plant Resources
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• v.33 no.4
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• pp.245-254
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• 2020

This study was conducted for the comparison of antioxidant activities in different cultivation areas, harvest date and processing statuses in the new variety 'Sammany' of Gomchwi (Fischer ligularia). The lowland was Gangneung, 20 m above sea level, and the highland was Daegwallyeong, 750 m above sea level. The total phenolic contents, flavonoids, DPPH free radical scavenging activities, and reducing power were analyzed by freezing and drying the raw and blanched of Gomchwi leaves from April 18th to July 15th, and extracting them through in the use of methanol. Total phenolic contents, flavonoids, DPPH free radical scavenging activities and reducing power were found to be more pronounced during May than they were in the period of early harvest on April 18th in the lowland, as well as to be more effective during June than in May in the highland. Total phenolic contents, flavonoids, DPPH free radical scavenging activities, and reducing power by region, harvest date, and processing status were more effective in May than the early harvest of April in flat areas, and antioxidant activity in the highlands was elevated as of June. When compared with raw and blench leaves, raw leaves exhibited higher antioxidant activities across the board. Highland cultivation also displayed higher antioxidant activities than did lowland cultivation. Combining the above results, the 'Sammany' variety of Gomchwi was found to be more active in terms of antioxidants, which were harvested in May in flat areas and June in the highlands. Also, consuming them raw showed higher antioxidant activity than when blanched.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.1
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• pp.352-360
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• 2010

The purpose of this study was to examine potential effects of nature- friendly hill climb sportsmen's participatory motivation and commitment experience on their sense of self-achievement and living satisfaction. To meet the goal, this study surveyed total 206 participants (male and female) in hill climb tournaments held at Daegwallyeong and Misiryeong, Gangwon province. For data processing, this study used SPSS 14.0 and amos 7.0 to conduct frequency analysis, reliability analysis, correlation analysis, descriptive statistic analysis and structural equation model analysis respectively. As a result, this study could come to the following conclusions: First, according to descriptive statistic analysis, it was found that our respondents who participated in nature-friendly hill climb sports scored relatively high points in their participatory motivation, commitment experience, sense of self-achievement and living satisfaction. Secondly, this study adopted Pearson's moment correlation analysis in order to determine potential associations among our respondents' participatory motivation, commitment experience, sense of self-achievement and living satisfaction. As a result, it was found that their participatory motivation was positively correlated with their living satisfaction, while their commitment experience was positively correlated with their sense of self-achievement. Thirdly, it was found that there were certain causalities among our respondents' participatory motivation, living satisfaction, commitment experience and sense of self-achievement.

• Journal of the Korean Geographical Society
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• v.43 no.5
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• pp.715-727
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• 2008

This study analyzed changes on the best condition of temperature and relative humidity for making artificial snows in the Yongpyong Ski Resort using data from Daegwallyeong. Depth of snowfall and snowfall days have decrease since 1990s. If the Yongpyong Ski Resort has only to depend on natural snows, it would be difficult to make and maintain ski slope. There are two times of snowmaking during ski seasons: one is the first snowmaking (October-November) for opening ski slopes and the other is the reinforcement of snowmaking (December-March) for maintaining snow quality during the seasons. Days having the best condition for the first snowmaking (daily minimum temperature below $-1^{\circ}C$ and daily average relative humidity 60 to 80 percent) decreased after 1970s. Days having the best condition for the reinforcement of snowmaking also decreased. While temperature changes are more evident than humidity changes for the first snowmaking, humidity changes are more obvious than change of temperature for the reinforcement of snowmaking. In the future climate projection by A1B scenarios, the length of ski seasons projected to decrease a 10 to 40 percent against the period of 1973-2008. The climate condition for the snowmaking projected to be poor, especially the due to increase of temperature.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.1
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• pp.102-109
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• 2008

This study was performed to obtain fundamental information on growth adaptability and isoflavone contents of soybean cultivars in highland area of Korea. For this study, we cultivated nineteen cultivars and investigated yield and isoflavone contents. In Jinbu-myeon located at altitude of 600 m, most of cultivars showed more than 2.5 t/ha seed yield except three cultivars, and the range of isoflavone contents among nineteen cultivars was 715 to $2,545\;{\mu}g/g$. Cultivars with both high seed yield and isoflavone contents were Manrikong, Sinpaldalkong2, Cheongjakong, and Cheongjakong2 in this area. In Daegwallyeong-myeon located at altitude of 800 m, the range of seed yield and isoflavone contents was 1.4 to 2.4 t/ha and 437 to $2,370\;{\mu}g/g$, respectively. Cultivars with both high seed yield and isoflavone contents were Ilpumgeomjeongkong and Dooyookong in this area. Cultivars selected on the basis of seed yield and isoflavone contents in 2004 and 2005 showed also similar results for yield and isoflavone contents at farmer's field in highland area in 2006. In conclusion, it could be expected to produce soybeans having both higher yield and better quality if the selected soybean cultivars are cultivated in highland area.

• Journal of the Korean Geographical Society
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• v.37 no.3
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• pp.237-246
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• 2002

This study classified wintertime bioclimatic zones of South Korea based on daytime and nighttime distribution of wind chill index calculated from climate data during the coldest month for latest 30 years (1971- 2000). The results show that the winter daytime and nighttime wind chill index were influenced by climatic factors such as elevation, land-sea breeze, topology, and sea currents etc. as well as climatic components such as temperature, wind speed, and sunshine, so that South Korea was divided into five bioclimatic zones; Cool day- cold night zone, Keen day- Cold night zone, Keen day-Very Cold night zone, Cold day and night zone, and Cold day-Extremely Cold night zone. Especially, coasts and island areas, except for south coast of Korea, shows Keen bioclimatic response during daytime and Very Cold bioclimatic response during nighttime. This indicates that coasts and island areas, except for south coast of Korea are affected by moonson and land-sea breeze. In addition, highly elevated Daegwallyeong shows Cold bioclimatic response during daytime and Extremely Cold during nighttime due to the influence of adiabatic temperature lapse rate and monsoon. This study offers basic data necessary to make decisions concerning insulation such as clothing and architect etc. by classifying winter bioclimatic zones of South Korea based on various daytime and nighttime distribution of wind chill.

• Korean Journal of Agricultural and Forest Meteorology
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• v.18 no.1
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• pp.55-63
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• 2016

Temperature lapse rate within the planetary boundary layer shows a diurnal cycle with a substantial variation. The widely-used lapse rate value for the standard atmosphere may result in unaffordable errors if used in interpolating hourly temperature in complex terrain. We propose a simple method for estimating hourly lapse rate and evaluate whether this scheme is better than the conventional method using the standard lapse rate. A standard curve for lapse rate based on the diurnal course of temperature was drawn using upper air temperature for 1000hPa and 925hPa standard pressure levels. It was modulated by the hourly sky condition (amount of clouds). In order to test the reliability of this method, hourly lapse rates for the 500-600m layer over Daegwallyeong site were estimated by this method and compared with the measured values by an ultrasonic temperature profiler. Results showed the mean error $-0.0001^{\circ}C/m$ and the root mean square error $0.0024^{\circ}C/m$ for this vertical profile experiment. An additional experiment was carried out to test if this method is applicable for the mountain slope lapse rate. Hourly lapse rates for the 313-401m slope range in a complex watershed ('Hadong Watermark 2') were estimated by this method and compared with the observations. We found this method useful in describing diurnal cycle and variation of the mountain slope lapse rate over a complex terrain despite larger error compared with the vertical profile experiment.

• Korean journal of applied entomology
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• v.44 no.3 s.140
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• pp.225-230
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• 2005

This study was conducted to investigate the developmental characteristics of cabbage armyworm, Mamestra brassicae L. (Lepidoptera: Noctuidae) by different temperatures and its seasonal occurrence in pepper field. Under four constant temperatures, 15, 20, 22 and $25^{\circ}C$, developmental periods from egg to adult were 88.3, 63.0, 52.3, and 42.8 days, respectively, with egg periods being 9.2, 6.2, 5.0 and 3.9 days, and larval periods being 40.5, 30.1, 23.3 and 21.2 days, respectively. Developmental threshold and thermal requirement in degree-days (DD) were $7.9^{\circ}C$ and 69.4 DD for egg, $4.8^{\circ}C$ and 434.8 DD for larva and $6.7^{\circ}C$ and 344.8 DD for pupa. Fecundity of female increased as temperature increased laying 1262.1 eggs at $15^{\circ}C$, 1663.8 eggs at $20^{\circ}C$ and 1763.2 eggs at $25^{\circ}C$. Mean numbers of eggs per egg-mass were 99.4, 114.7 and 167.9 under the three constant temperatures, respectively. In Daegwallyeong highland area, this noctuid occurred from mid June to late August and has two generations a year reaching peak two times, one at late June and the other at early August.

• Atmosphere
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• v.28 no.4
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• pp.369-382
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• 2018

Planetary boundary layer height (PBLH), produced by the Local Data Assimilation and Prediction System (LDAPS), was verified using RawinSonde (RS) data obtained from observation at Daegwallyeong (DGW) and Sokcho (SCW) during the International Collaborative Experiments for Pyeongchang 2018 Olympic and Paralympic winter games (ICE-POP 2018). The PBLH was calculated using RS data by applying the bulk Richardson number and the parcel method. This calculated PBLH was then compared to the values produced by LDAPS. The PBLH simulations for DGW and SCW were generally underestimation. However, the PBLH was an overestimation from surface to 200 m and 450 m at DGW and SCW, respectively; this result of model's failure to correctly simulate the Surface Boundary Layer (SBL) and the Mixing Layer (ML) as the PBLH. When the accuracy of the PBLH simulation is low, large errors are seen in the mid- and low-level humidity. The highest frequencies of Planetary boundary layer (PBL) types, calculated by the LDAPS at DGW and SCW, were presented as types Ι and II, respectively. Analysis of meteorological factors according to the PBL types indicate that the PBLH of the existing stratocumulus were overestimated when the mid- and low-level humidity errors were large. If the instabilities of the surface and vertical mixing into clouds are considered important factors affecting the estimation of PBLH into model, then mid- and low-level humidity should also be considered important factors influencing PBLH simulation performance.

• Atmosphere
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• v.29 no.3
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• pp.311-324
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• 2019

We employed a Multi-Angle Snowflake Camera (MASC) to quantitatively analyze snow particles at the ground level in the Yeongdong region of Korea. The MASC captures high-resolution photographs of hydrometeors from three angles and simultaneously measures fallspeed. Based on snowflake images of the several episodes in 2017 and 2018, we derived statistics of size, aspect ratio, orientation, complexity, and fallspeed of snow crystals, which generally showed similar characteristics to the previous studies in other regions of the world. Dominant snow crystal habits of January 22, 2018 generated by northerly were melted aggregates when 850 hPa temperature was about $-6{\sim}-8^{\circ}C$. Average fallspeed of snow crystals was $1.0m\;s^{-1}$ though its size gradually increased as temperature decreased. Another snowfall event (March 8, 2018) was driven by the baroclinic instability as accompanied with a deep trough. Snow crystal habits were largely rimed aggregates (complexity ~1.8) and melting particles of dark images. Meanwhile, in the extreme snowfall event whose snow rate was greater than $10cm\;hr^{-1}$ on January 20, 2017, main snow crystals appeared to be heavily rimed particles with relatively smaller size when convective clouds developed vertically up to 9 km in association with tropopause folding. MASC also could successfully measure a decrease in snow crystal size and an increase in riming degree after AgI seeding at Daegwallyeong on March 14, 2017.