• Journal of Climate Change Research
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• v.7 no.4
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• pp.493-498
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• 2016

This study was conducted to investigate the effect of environment factors on full bloom stage and fruit width in four peach cultivars. The average temperature in March was the main factor to determine the date of full bloom in 'Kurakatawase'($-0.6871^*$) and 'Changhowon Hwangdo'($-0.5270^*$). The fruit growth curve after 35 days from full bloom was the double sigmoid shape in 'Changhowon Hwangdo' cultivar. Environmental factors affecting fruit width were mean diurnal range(BIO2) and temperature annual range(BIO 7) in 'Kurakatawase', growing degree days(GDD) after 30 days from full bloom and July precipitation in 'Yumyeong', and annual mean temperature(BIO1), BIO7, and July precipitation in 'Kawanakajima Hakuto'. Of these, major environmental factors affecting fruit width in more than two cultivars were BIO7 and July precipitation.

• Ocean and Polar Research
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• v.30 no.3
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• pp.335-345
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• 2008

In order to study spatial variabilities and major controlling factors, we measured fugacity of $CO_2(fCO_2)$, temperature, salinity and nutrients in surface waters of the North Pacific($7^{\circ}30'{\sim}33^{\circ}15'N$, $123^{\circ}56'E{\sim}164^{\circ}24'W$) between September$\sim$October 2007. The North Pacific and the marginal sea were distinguished by $fCO_2$ distribution as well as unique characteristics of temperature and salinity. There was a distinct diurnal SST variation in the tropical North Pacific area, and surface $fCO_2$ coincidently showed diurnal variation. In the North Pacific area, surface $fCO_2$ was mainly controlled by temperature, while in the marginal sea area it was primarily dependent on alkalinity and dissolved inorganic carbon concentrations. Air-sea $CO_2$ flux showed a large spatial variation, with a range of $-6.10{\sim}5.06\;mmol\;m^{-2}day^{-1}$. The center of subtropical gyre of North Pacific acted as a source of $CO_2(3.09{\pm}0.95\;mmol\;m^{-2}day^{-1})$. Tropical western North Pacific (i.e. the 'warm pool' area and the subtropical western North Pacific) acted as weak sources of $CO_2$($1.07{\pm}1.20\;mmol\;m^{-2}day^{-1}$ and $0.50{\pm}0.53\;mmol\;m^{-2}day^{-1}$, respectively). In the marginal sea, however, the flux was estimated to be $-0.68{\pm}1.17\;mmol\;m^{-2}day^{-1}$, indicating that this area acted as a sink for $CO_2$.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.3
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• pp.225-236
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• 2000

Diurnal variations of wind field and pollutant dispersion over the Yosu area under the insolation conditions of summer and winter were investigated by using the Regional Atmospheric Modeling System (RAMS). Initially, horizontally homogeneous wind field were assumed on the basis of sounding data at the Kwangju upper-air station for days whose morning wind speeds were below 2m/s. In these days, the sea breeze prevailed in summer while the land breeze lasted for a few hours in the morning; the effect of synoptic winds was strong in winter with some inclusion of wind variations owing to the interaction between sea and land. The predicted wind direction at the location of the Yosu weather station captured an important change of the sea-land breeze of the observed one. The predicted wind speed and the air temperature agreed with observed ones in a reasonable range. In the morning, both in summer and winter, winds around the source location were diverged and became weak between the mountainous area to the southeast and the Kwangyang Bay to the north. Winds, however, accelerated while blowing to the east and south and blowing on the mountainous area. Complicated wind fields resulted in high pollutant concentrations at almost all receptors considered. These high concentrations in the morning were even comparable to the ISCST3 calculations with the worst-case and typical meteorological conditions designated by USEPA(1996). On the other hand, in the afternoon, the wind field was rather uniform even in the mountainous area with development of mixing layer and the concentration distributions being close to the Gaussian distributions.

• Proceedings of the Korean Quaternary Association Conference
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• 2004.06a
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• pp.29-29
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• 2004

Long term observational analysis by climatologists has confirmedthat the global warming is no longer a topic of debate among scientists andpolicy makers. According to the report of IPCC-2001 (Intergovernmental Panelon Climate Change), the global mean surface air temperature is increasinggradually. The reported increase of mean temperature is by 0.6 degree in the end of twentieth century. This could represent severe threat for propertylosses especially due to increase in the number of extreme weather arising out of global warming. period of model integration from 2001 to 2100 using output of ECHAM4/HOPE-G of Max Planet Institute of Meteorology (MPI) for IPCC SRES (Special Report on Emission Scenarios). The main results of this study indicate increase of surface air temperature by 6.20C and precipitation by 2.6% over Korea in the end of 21st century. Simulation results also show that there is increase in daily maximum and minimum temperatures while decrease in diurnal temperature range (DTR). DTR changes are diminished mainly due to relatively rapid increase of daily minimum temperature than that of daily maximumtemperature. It has been observed that increase in precipitation amount anddecrease in the number of rainy days lead to increase of pre precipitationintensity.

• Journal of Environmental Science International
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• v.8 no.2
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• pp.145-150
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• 1999

To estimate the thermal effect of the vegetation canopy on the surface sublayer environment numerically, we used the combined model of Pielke's1) single layer model for vegetation and Deardorff's2) Force restore method(FRM) for soil layer. Application of present combined model to three surface conditions, ie., unsaturated bare soil, saturated bare soil and saturated vegetation canopy, showed followings; The diurnal temperature range of saturated vegetation canopy is only 20K, while saturated bare soil and unsaturated bare soil surface are 30K, 35K, respectively. The maximum temperature of vegetation canopy occurs at noon, about 2 hours earlier than that of the non-vegetation cases. The peak latent heat fluxes of vegetation canopy is simulated as a 600Wm-2 at 1300 LST. They have higher values during afternoon than beforenoon. Furthermore, the energy redistribution ratios to latent heat fluxes also increased in the late afternoon. Therefore, oasis effect driving from the vegetation canopy is reinforced during late afternoon compared with the non-vegetated conditions.

• Journal of Environmental Science International
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• v.8 no.3
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• pp.287-292
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• 1999

This study was performed to investigate the characteristics of nocturnal maxiumu ozone occurrence and the meteorological relevance using to hourly ozone data and meteorological data for 1995~1996 in Pusan coastal area. Kwangbokdong showed the highest occurrence of nocturnal maximum ozone as 36.9%, and Deokcheondong showed the lowest occurrence(9.2%) for research period in Pusan. The occurrence rates of nocturnal maximum ozone concentration were decreased toward land area. The low maximum temperature, high minimum temperature, low diurnal range, high relative humidity, high wind speed, high could amount, low sunshine and low radiation were closely related to the main meteorological characteristics occuring the nocturnal maximum concnetration of ozone. It was shown that normal daily variation of ozone concentration by strong photochemical reaction at the before day of nocturnal maximum ozone. The concnetration of nocturnal maximum ozone were occured by entrainment of ozone from the upper layer of developed mixing layer. There are no ozone sources near the ground at night, so that the nighttime ozone should be entrained from the upper layer by forced convection.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.1
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• pp.61-68
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• 2000

Gas-phase hydrogen peroxide(H2O2) concentrations were measured to investigate it's distribution in the ambient air in downtown Seoul(Kwanghwamum and Mullae-dong). These measurements were made during four season, from April 30, 1998 to January 29, 1999, using Cold Trap and HPLC. Measurements were also made of other photochemical oxidants and trace gases(O3, NO2, CO and SO2) and meteorological parameters(relative humidity, temperature, solar radiation and wind speed). The mean of all observations was 0.10 ppbv and the range measured was below the level of detection(>0.01 ppbv) to 0.47ppbv. The higher seasonal mean concentrations showed during the summer(0.21 ppbv) and concentrations of H2O2 showed a diurnal variation with maximum concentrations in the afternoon(12:30∼14:00). The results from the corrrelation analysis showed that the concentration of gaseous H2O2 is strongly dependent on the other air pollutants(NO2, CO and O3) and meteorological parameters(relative humidity, temperature and solar radiation.)

• International Journal of Highway Engineering
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• v.15 no.5
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• pp.195-202
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• 2013

PURPOSES : This study analyzed the regional dew possibility in road sign using meteorological data. METHODS : Four years of meteorological data such as temperature, humidity, dew point, wind velocity were collected and analyzed. As a result of literature review, dew was frequent in large diurnal range, high humidity and weak wind. So, dew possibility was analyzed by (temperature-dew point ${\leq}1^{\circ}C$ and wind velocity ${\leq}$ 1.5m/s). RESULTS : The possibility was analyzed for each meteorological observation point and the point of Suncheon and Bonghwa were selected as the most likely points of dew in road sign. The area of East Coast, Kyungbuk and Kyungnam were relatively low potential. CONCLUSIONS : Alternative with high effect of preventing dew should be selected in high possibility dew area despite of low economics.

• 보존과학연구
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• s.24
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• pp.169-184
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• 2003

Yearly mean temperature and relative-humidity of the Seokguram Grotto was measured $19~23^{\circ}C$, 40~44% from May, 1998 to December,2002. The measurement has little differences comparing to the optimum guideline (temperature : $20^{\circ}\pm2^{\circ}C$, relative-humidity : $50^{\circ}\pm5%$). It is necessary to increase humidity in the Seokguram Grotto during winter because of heating and decrease the temperature during summer because of a higher temperature of outside. In addition, the diurnal range keep in $4^{\circ}C$ of temperature and in 10% of relative-humidity. Yearly mean concentration of $CO_2$(carbon dioxide) was measured538~658ppm that is higher than concentration of normal atmosphere(360 ppm). The $CO_2$ has an cumulative effect on the surface of stone cultural properties as a form of carbonic acid($H_2CO_3$) after reaction with water. HVAC (Heating, Ventilation and Air Conditioning) system should be operated to maintain ideal state for the preservation according to the optimum guideline. Also, the entrance into the Seokguram Grotto should be controlled to prevent a sudden fluctuation of humidity and temperature. Human could carry small particles like a microdust, microbe, etc., into the Seokguram Grotto and also could damage the surface by a direct touch.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.6
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• pp.451-461
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• 1997

The soil NO flux measurements in Korea were made from 17 May 1997 to 16 June 1997 on grass land at Kunsan National University in southwestern Korea by using flow-through chamber technique. The experiment was conducted in an effort to determine the role of natural emissions of NO on rural atmospheric photochemistry, and to understand the soil NO emission mechanism with respect to soil parameters. Soil NO fluxes were measured every minutes and averaged in every 15 minutes as well as soil temperature. Soil samples were analyzed for $NO_3^-, NH_4^+$, and moisture in soil. Soil nitrate was not detected in most times, and total N-containing was limited in site soils. There was a optimum range of soil moisture and temperature for soil NO flux. The overall average of soil NO emission rates were found to be 1.30 $\pm 0.92 ngNm^{-2}s^{-1}$ (n=1219), and ranged from 0.01 ngNm^{-2}s^{-1}$ to 5.62 ngNm^{-2}s^{-1}$. Diurnal variation of soil NO emission was typical, which was in higher level during daytime, and was in lower level over the night. NO flux showed a strong soil temperature dependence $(r^2=0.78)$, but not with soil moisture and soil N-containing during this experimental period; NO fluxes increased exponentially as soil temperature increased. In order to assure the relevant relationship between soil NO flux and the soil parameters, long-term soil flux measurement on different types of land use should be planned and conducted continuously.