• Journal of Environmental Science International
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• v.12 no.4
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• pp.399-417
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• 2003

The seasonal variation and frequency of rainfalls of Korea peninsula in Changma period show strong local weather phenomenon because of it's topographical and geographical factors in Northeast side of Asia. Based on weather entropy(statistical parameter)-the amount of average weather information-and information ratio, we can define each area's weather representativeness, which can show us more constant form included topographical and geographical factors and seasonal variation. The data used for this study are the daily precipitation and cloudiness during the recent ten years(1990-1999) at the 73 stations in Korea. To synthesize weather Entropy, information ratio of decaying tendency and half$.$decay distance, Seoul's weather representativeness has the smallest in Summer Changma period. And Puyo has the largest value in September.

• Environmental Engineering Research
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• v.14 no.1
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• pp.13-18
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• 2009

In this study, specific pollutant releases during the Asian monsoon season were estimated and the information was applied to the non-point pollutant sources management from two forested watersheds of the Soyang Lake. The two watersheds are part of the 2,703 km2 Soyang Lake watershed in the northern region of the Han River. The outlets of the two watersheds were respectively analyzed for continuous water quality concentration and for discharge during various single rainfall events. Statistical power function methods are utilized to compare stream discharge and pollutant flux release during the study period. Based on the monitoring data during the study period, the specific load flux method using simulated discharge was conducted and validated in the two watersheds. The model predictions corresponded well with the measured and calculated pollutant releases. The modeling approach taken in this study was found to be applicable for the two forested watersheds.

• Journal of the Korean Institute of Landscape Architecture
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• v.21 no.4
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• pp.69-82
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• 1994

The purpose of this study is to estimate the probable period of the planting work in consideration of weather factors. The impact degree of weather factors on the control of planting schedule was measured by the possible working days on the basis of weather condition. To establish the weather standard, the researcher analyzed the questionnaires on the manager of planting work and also the meteorological data for 10 years(1983-1992) in Seoul. The results are as follows; $\circled1$ The possible period of the planting work is from March 17 to May 18 Spring and from September 26 to December 15 in Autumn during a year. $\circled2$ The problem working days of the planting work(106-130) days per year) are less than the building construction days(174 days per year), because of handling the living material of plants, specially in summer and winter.

• KCID journal
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• v.13 no.1
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• pp.82-90
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• 2006

The practical date of rice growing stages and the date for calculating the water demand in paddy field have differences. The causes are rice planting water requirement, nursery bed area and change of average temperature and so on. Some recent papers have shown the same results. So we have investigated the nursery period, rice transplanting period and mid-summer drainage and developed a system for estimating water demand. And we calculated the water demand by using the system. The result showed that calculation by using the new system is more appropriate than the calculation by using the established period. But because water losses in canals and crop coefficient are not determined appropriately, we can calculate the agricultural water demand more accurately by dstablishing canal losses ratio, crop coefficient and so on.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.14 no.2
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• pp.125-137
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• 1985

Standard weather data for Seoul has been developed for use in computer calculations for energy requirements, and the 8760 sequential hourly values for seven weather elements have been placed in magnetic tape and cards. Applying the method determining average month, developed by Japanese Society of Heating, Air-Conditioning and Sanitary Engineers, the standard year data have been selected from the monthly average values for three weather elements during the 10year period of 1971 through 1980. The followings are obtained. 1. The Test Reference Year, consisting of 12 months chosen from different calendar years, has been determined, and TRY tape which contains seven weather elements has been prepared. 2. The Typical Weather Year, which means a year close to the average value, is the year of 1978 during the above 10 year period. 3. During the period, Winter Season needs the maximum heating load is from Dec. 1976 to Mar. 1977 and Summer Season needs the maximum cool ins load is from Jun. to Sep, 1978.

• Weed & Turfgrass Science
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• v.6 no.2
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• pp.151-156
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• 2017

Summer patch is the most serious disease at turfgrass field or golf course established with Kentucky bluegrass during high temperature season in Korea. Nevertheless, chemicals for the summer patch control are not yet registered in Korea. We isolated the pathogens from the turfgrass showing typical summer patch symptoms and identified as Magnaporthiopsis poae by using the internal transcribed spacer ITS1 and ITS4 sequences of rDNA. The inhibition rates of the pathogen were investigated for 10 fungicides. As results, the pathogen growth was suppressed when chemicals concentration increased and negatively correlated with incubation period with the chemicals. In triazole group, all chemicals (metconazole, myclobutanil, propiconazole and tebuconazole) treated showed the inhibition rates by 100%. Thiophanate-methyl showed the next highest inhibition effect against a summer patch pathogen. In strobilurin group, pyraclostrobin was the highest suppression effect compared with azoxystrobin and trifloxystrobin. Inhibition effect of fludioxonil and fluxapyroxad on pathogen was similar to the trifloxystrobin. Based on the results, triazole and carboxamide groups are strongly recommended due to the highest inhibition effect on the summer patch pathogen, Magnaporthiopsis poae.

• Journal of Environmental Science International
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• v.23 no.10
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• pp.1719-1729
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• 2014

This study is carried out in order to bridge the gap to understand the relationships between South Asian and East Asian monsoon systems by comparing the summer (June-September) precipitation of Nepal and South Korea. Summer monsoon precipitation data from Nepal and South Korea during 30 years (1981-2010) are used in this research to investigate the association. NCEP/NCAR reanalysis data are also used to see the nature of large scale phenomena. Statistical applications are used to analyze these data. The analyzed results show that summer monsoon precipitation is higher over Nepal ($1513.98{\pm}159.29mm\;y^{-1}$) than that of South Korea ($907.80{\pm}204.71mm\;y^{-1}$) and the wettest period in both the countries is July. However, the coefficient of variation shows that amplitude of interannual variation of summer monsoon over South Korea (22.55%) is larger in comparison to that of Nepal (10.52%). Summer monsoon precipitation of Nepal is found to be significantly correlated to that of South Korea with a correlation coefficient of 0.52 (99% confidence level). Large-scale circulations are studied to further investigate the relationship between the two countries. wind and specific humidity at 850 hPa show a strong westerly from Arabian Sea to BOB and from BOB, wind moves towards Nepal in a northwestward direction during the positive rainfall years. In case of East Asia, strong northward displacement of wind can be observed from Pacific to South Korea and strong anticyclone over the northwestern Pacific Ocean. However, during the negative rainfall years, in the South Asian region we can find weak westerly from the Arabian Sea to BOB, wind is blowing in a southerly direction from Nepal and Bangladesh to BOB.

• Journal of Korea Water Resources Association
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• v.44 no.5
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• pp.339-350
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• 2011

This study developed a climate informed Bayesian nonstationary frequency model which allows us to forecast seasonal summer rainfall at Nakdong River. We constructed a 37-year summer rainfall data set from 10 weather stations within Nakdong river basin, and two climate indices from sea surface temperature (SST) and outgoing longwave radiation (OLR) were derived through correlation analysis. The selected SST and OLR have been widely acknowledged as a climate driver for summer rainfall. The developed model was applied first to the 2010-year summer rainfall (888.1 mm) in order to assure ourself. We demonstrated model performance by comparing posterior distributions. It was confirmed that the proposed model is able to produce a reasonable forecast. The forecasted value is about 858.2 mm, and the difference between forecast and observation is about 30 mm. As the second case study, 2011-year summer rainfall forecast was made using an observed winter SSTs and an assumed 50% value of OLRs. The forecasted value is 967.7 mm and associated exceedance probability over average summer rainfall 680 mm is 92.9%. In addition, 50-year return period for summer rainfall was projected through the nonstationary frequency model. An exceedance probability over 1,400 mm corresponding to the 50-year return level is about 73.7%.

• Journal of the Korean Institute of Landscape Architecture
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• v.35 no.1 s.120
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• pp.88-93
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• 2007

Since the 1990s, the application of Kentucky bluegrass cultivars has increased in newly-constructed Korean golf courses as opposed to the previously-used zoysiagrass. However, there have been few reports studying the selection and characterization of these Kentucky bluegrass cultivars under Korean weather conditions. A total of 12 Kentucky bluegrass cultivars were tested for their adaptability in environmental stresses during summer conditions in Korea in order to select the best Kentucky bluegrass cultivars for use in Korean golf courses. This study found that two Kentucky bluegrass cultivars ('Midnight' and 'Bluestone') maintained their green throughout the summer season and had a high degree of root density, as compared to the other cultivars tested. These two cultivars also had a good rate of coverage in the early growth period. These characteristics make them suitable for application on sports fields and golf courses, which receive many divots and the frequent replacement of turfgrass sod caused by both biotic and abiotic stress. Two other cultivars, the 'Ginney' and 'Nuglade', also displayed good visual quality and high rate of coverage under summer conditions. In conclusion, the 'Midnight' and 'Bluestone' cultivars performed well in areas including the maintenance of their green color, the number of roots and the rate of coverage during the summer months. These characteristics are necessary for golf courses sports fields, which receive many divots and requirethe frequent replacement of turfgrass. further research on a range of Kentucky bluegrass cultivars, including a sensitivity test for many pathogens and recovery rates from a variety of stresses, is required in the near future.

• Atmosphere
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• v.27 no.4
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• pp.435-444
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• 2017

By analyzing Asian Precipitation-Highly-Resolved Observational Data Integration Towards Evaluation (APHRODITE) from May to September for 1951~2007, this study investigates impacts of two dominant boreal summer intraseasonal oscillation (BSISO) modes on precipitation over Monsoon Asia including Korea and long-term change of 10~20-day and 30~60-day ISO over Korea. It is shown that BSISO strongly modulates rainfall variability over the many part of Monsoon Asia including Korea. Korea tends to have more (less) rainfall during the phases 3~5 (7~8) of BSISO1 representing the canonical northward/northeastward propagating 30~60-day ISO and during the phases 6~8 (3~5) of BSISO2 representing the northward/northwestward propagating 10~20-day ISO. It is found that the 10~20-day ISO variability contributes to summer mean rainfall variability more than 30~60-day ISO over Korea. For the 57 years of 1951~2007, the correlation coefficient between the May to September mean precipitation anomaly and standard deviation of 10~20-day (30~60-day) ISO is 0.71 (0.46). It is further noted that there is a significant increasing trend in the 10~20-day and 30~60-day ISO variability in the rainy season during the period of 1951 to 2007.