• Asian Journal of Atmospheric Environment
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• v.9 no.3
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• pp.214-221
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• 2015

This study considers mean skin temperature to calculate expected temperature using the new heat balance model because the skin temperature is the most important element affecting the heat balance outdoors. For this, we measured the skin temperature in high temperature condition of Korea and applied it to calculate the expected temperature. The calculated expected temperature is compared with the result calculated using previous models which use the estimated mean skin temperature by considering metabolic rate only. Results show that the expected temperatures are higher when measured mean skin temperature is applied to the model, compared to the expected temperature calculated by applying mean skin temperature data calculated using metabolic rate like previous models. The observed mean skin temperature was more suitable for outside conditions and expected temperature is underestimated when mean skin temperature calculated by the equation using metabolic rate is used. The model proposed in this study has a few limitations yet, but it can be applied in various ways to facilitate practical responses to extreme heat.

• Journal of Environmental Science International
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• v.17 no.8
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• pp.907-918
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• 2008

In order to monitor the impact of high temperature which is seen frequently with climate change, we investigated the monthly change in globe temperature, air temperature, mean radiant temperature and effective radiant heat flow, because the four well reflect thermal radiation from bio-meteorological aspect. Both globe temperature and air temperature showed an increasing trend every month. Compared to air temperature, globe temperature had a wider range of temperature change and was more influenced by meteorological element such as precipitation. Diurnal trends of air temperature, globe temperature and the difference between their temperature had the lowest value before the sunrise and the highest around $1300{\sim}1500$ LST, showing the typical diurnal trends. Globe temperature and the difference between their temperature had a sharp increase around $1000{\sim}1100$ LST, maintained high value until 1700 LST and then reclined, though varied by month. The difference between globe temperature and air temperature was highly dependent on the amount of precipitation and clouds. The duration in which globe temperature was higher than air temperature was the lowest in July. Therefore the amount of precipitation was the most affecting, followed by the amount of clouds and wind. In order to find out the diurnal trends of temperature in city center and city outskirts, we assumed the roof of a concrete build ing as a city center, and the grass-covered observatory of the Gimhae International Airport as city outskirts. The diurnal trends of temperature in the two sites showed a strong correlation. The highest and lowest temperature also had the same trend.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.5
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• pp.523-537
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• 2008

In Korea, the global warming leads to more frequent high temperature region. increasing the need for research into physical damage caused by high temperature. We therefore analyzed the differences of mortality, caused by extreme heat, among gender and age. We also examined the trend of mortality from high temperature-sensitive diseases. Women are more affected by exposure to high temperature than are men; People over 65 years old have higher mortality rate (1.5 times) than under 65. As for high temperature-related diseases, cerebrovascular disease was the number one cause of death, and chronic lower respiratory disease and cardiovascular disease followed.

• Journal of the Korean Society for Precision Engineering
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• v.11 no.2
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• pp.173-181
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• 1994

A Cold spot temperature control system for the batch annealing furnace has been estabilished in order to reduce energy consumption to improve productivity and stabilize the propertics of products. Therefore we confirmed a relation between annealing cycle time and atmospheric gas, variation of coil cold spot temperature with time during heating and actual temperature measurements at mid-width of each coil during heating and actual temperature measurements at mid-width of each coil during soaking. The results of the tempaeature variation effect on the batch annealing are as follows. 1) Heating time is reduced to one half with increasing atmospheric gas flow rate and changing of atmospheric gas component from HNx to Ax gas, and annealing cycle time is reduced to 2.7 times. 2) In case of short time healing, the slowest heating part is the center of B coil, in case of long time heating, the low temperature point moves from the center of coil to inside coil. And the temperature in this part is higher than other parts when cooling. When finished heating, the cold spot is located 1/3 of coil inside in case of HNx atmospheric gas. But center of coil in case of Ax atmospheric gas. 3) The outside of top coil is the highest temperature point when heating, which becomes the lowest temperature point when cooling. So, this point becomes high temperature zone at heating and low temperature zone at cooling, It has relation according to atmospheric gas component and flow rate. 4) Soaking time at batch annealing cycle determination is made a decision by the input coil width, and soaking time for quality homogenization of 1214mm width coil must be 2.5 hours longer than that of 914mm width coil for the same ciol weight. 5) Annealing cycle time with Ax atmospheric gas is extended 1 hour in of slow cooling during 5 hours in order to avoid rapid cooling.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.3
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• pp.193-204
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• 2002

To investigate the relationships between the atmospheric concentrations of PCBs and temperature, quantity of both parameters was performed at an urban site in Korea from July 1999 to January 2000. The strength of correlations between total PCB and temperature was found to be significant (r = 0.752, p < 0.001). It hence indicates that total PCB contents were affected sensitively by temperature change during the sampling period. The ratio of PCB homologs and Deca-CB(PCB 209) also behaved quite similarly to the change of temperature (r>0.60, p<0.05). This may be inferable with the progress of the gas/particle partitioning to the gas phase, especially for fri-and tetra-CBs. Because they have high vapor pressure, they generally exist in the gas phase. The Clausius-Clapeyron equation was applied to the atmospheric PCB data, relating PCB partial vapor pressure to inverse temperature. This may essentially represent the temperature-controlled transition between condensed phase and atmospheric gas phase. The slopes of the resulting plot with International Council for the Explanation of the Seas (ICES) congener ranged from -2810 to -5887, with significantly steep slope and $R^2$(p< 0.005) It was inferred that the PCB atmospheric concentration was also affected by change in the surrounding conditions such as soil, lakes and trees.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.418-421
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• 2005

In this study, we analyzed surface temperature of lakes in the Han River system, using Landsat-5 and -7 time-series images. Surface temperature was extracted using NASA equation and compared with in situ 10m-depth temperature in Lake Soyang and surface temperature on five other dam lakes downstream. The 24 images out of 29 showed standard deviation of temperature difference less than $2^{\circ}C$, to which a novel statistical atmospheric correction could be applied. The correlation coefficients were 0.950 at Lake Soyang and 0.979-0.997 at the other lakes after atmospheric correction.

• Atmosphere
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• v.23 no.1
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• pp.13-21
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• 2013

In this study, the effects of atmospheric stability and surface temperature on the microscale local airflow are investigated in a hydrological suburban area using a computational fluid dynamics (CFD) model. The model domain includes the river and industrial complex for analyzing the effect of water system and topography on local airflow. The surface boundary condition is constructed using a geographic information system (GIS) data in order to more accurately build topography and buildings. In the control experiment, it is shown that the topography and buildings mainly determine the microscale airflow (wind speed and wind direction). The sensitivity experiments of atmospheric stability (neutral, stable, and unstable conditions) represent the slight changes in wind speed with the increase in vertical temperature gradient. The differential heating of ground and water surfaces influences on the local meteorological factors such as air temperature, heat flow, and airflow. These results consequentially suggest that the meteorological impact assessment is accompanied by the changes of background land and atmospheric conditions. It is also demonstrated that the numerical experiments with very high spatial resolution can be useful for understanding microscale local meteorology.

• Journal of Biosystems Engineering
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• v.41 no.4
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• pp.337-341
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• 2016

Purpose: Evaluation of atmospheric conditions for proper timing of spray application is important to prevent off-target movement of crop protection materials. Susceptible crops can be damaged downwind if proper application procedure is not followed. In our previous study, hourly data indicated unfavorable conditions, primarily between evening 18:00 hrs in the evening and 6:00 hrs next morning, during clear conditions in the hot summer months in the Mississippi delta. With the requirement of timely farm operations, sub-hourly data are required to provide better guidelines for pilots, as conditions of atmospheric stability can change rapidly. Although hourly data can be interpolated to some degree, finer resolution for data acquisition of the order of 15 min would provide pilots with more accurate recommendations to match the data recording frequency of local weather stations. Methods: In the present study, temperature and wind speed data obtained at a meteorological tower were re-sampled to calculate the atmospheric stability ratio for sub-hour and hourly recommendations. High-precision evaluation of temperature inversion periods influencing atmospheric stability was made considering strength, time of occurrence, and duration of temperature inversion. Results and Discussion: The results indicated that atmospheric stability could be determined at different time intervals providing consistent recommendations to aerial applicators, thereby avoiding temperature inversion with minimal off-target drift of the sprayed liquid.

• Proceedings of the KSRS Conference
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• v.2
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• pp.864-867
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• 2006

Thermal infrared images of Landsat-5 TM and Landsat-7 ETM+ sensors have been unrivalled sources of high resolution thermal remote sensing (60m for ETM+, 120m for TM) for more than two decades. Atmospheric effect that degrades the accuracy of Sea Surface Temperature (SST) measurement significantly, however, can not be corrected as the sensors have only one thermal channel. Recently, MODIS sensor onboard Terra satellite is equipped with dual-thermal channels (31 and 32) of which the difference of at-satellite brightness temperature can provide atmospheric correction with 1km resolution. In this study we corrected the atmospheric effect of Landsat SST by using MODIS data obtained almost simultaneously. As a case study, we produced the Landsat SST near the eastern and western coast of Korea. Then we have obtained Terra/MODIS image of the same area taken approximately 30 minutes later. Atmospheric correction term was calculated by the difference between the MODIS SST (Level 2) and the SST calculated from a single channel (31 of Level 1B). This term with 1km resolution was used for Landsat SST atmospheric correction. Comparison of in situ SST measurements and the corrected Landsat SSTs has shown a significant improvement in $R^2$ from 0.6229 to 0.7779. It is shown that the combination of the high resolution Landsat SST and the Terra/MODIS atmospheric correction can be a routine data production scheme for the thermal remote sensing of ocean.

• Proceedings of the KSRS Conference
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• v.1
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• pp.250-252
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• 2006

The land surface temperature (LST) can be defined as a weighted average temperature of components which constitute a pixel. The coefficients of split-window algorithm for MTSAT-1R were obtained by means of a statistical regression analysis from radiative transfer simulations using MODTRAN 4.0 for a wide range of atmospheric, satellite viewing angle (SVA) and lapse rate conditions. 6 types of atmospheric profile data imbedded in the MODTRAN 4 are used for the radiative transfer simulations. The RMSE is clearly larger on warm and humid profiles than cold and dry profiles, especially when the satellite viewing angle and lapse rate are large. The derivation of LST equations according to the atmospheric profiles clearly decreased the RMSE without regard to the SVA and lapse rate. The bias and RMSE are decreased as the more controls factors included. This preliminary result indicates that the characteristics of atmosphere, SVA and lapse rate should be included in the LST equation.