• Journal of the Korean earth science society
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• v.23 no.5
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• pp.436-441
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• 2002

This study is concerned with the sea breeze criterion and climatological characteristics of the short-time sea breeze in the Gangneung coastal area. The sea breeze criteria in this area are listed here. First, the fact of the sea breeze blowing was considered to be a change of wind direction from land to sea and vice versa without terrain effect like easterly wind. Second, the sea breeze of which continuous time 1-hour or 2-hour was selected. Then the climatological characteristics of the short-time sea breeze were analyzed using the meterological data from a 10-year(1988${\sim}$1997) period. The climatological characteristics which were analyzed for the short-time sea breeze consist of the frequency, onset time, wind direction speed and temperature. Finally, this study will be helpful in meteorological application through the climatological characteristics of sea breeze along the east coast as well as Gangneung Airport.

• Journal of Korean Society for Atmospheric Environment
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• v.4 no.2
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• pp.67-71
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• 1988

To estimate the probability of short term concentration of air pollution using long term arithmetic average concentration, the procedure was developed and added to Texas Climatological Model version 2. In the procedure, such statistical characteristics that frequency distribution of short term concentration may be approximated by a lognormal distribution, were applied. This procedure is capable of estimating not only highest concentration for a variety of averaging times but also concentrations for arbitrary occurrence frequency. Evaluation of the procedure with the results of short term concentrations calculated by Texas Episodic Model version 8 using the meteorological data and emission data in Seoul shows that the procedure estimates concentrations fairly well for wide range of percentiles.

• Journal of the Korean Geographical Society
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• v.31
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• pp.42-67
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• 1985

• Journal of the Korean Institute of Navigation
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• v.18 no.4
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• pp.155-169
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• 1994

The minimum temperatures are important element in the daily human life, the climatic classification, and so on. In this study, the authors aim to make an analysis the distribution characteristics of minimum temperatures of 95 weather stations in Korea by using the Climatological Standard Normals of Korea VolumeI, VolumeII, and the Climatological Standard Normals of North Korea. The important results are as follows 1) The daily, fifthly, and tenthly minimum temperatures show the highest rate of occurrance on 14th of January( Occurrance rate : 56.6% ), 16~20th of January( 37.6% ), and the middle ten days of January( 82.1% ) respectively. 2) In the regional distribution of minimum temperatures in winter, the values of northern part, inland area, and west coastal region are lower than those of southern, coastal, and east coastal regions respectively. And, bigger cities and industrial area( Seoul, Incheon, Daejeon, Daegu, etc. ) have larger values than the its vicinities. 3) When the daily minimum temperature is $0^{\circ}C$ and less, the days of northern part, inland area, and wests coastal region are higher than those of southern, coastal, and east coastal regions respectively.

• Journal of Environmental Science International
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• v.25 no.6
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• pp.897-904
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• 2016

We investigated the local climatological characteristics of the mountain adjacent the Dongyeong herb garden in Chilgok. We established one set of automatic weather system (AWS) on a hill where development of herb garden is in progress. The observations were continued for 2 years(2013. 07-2015.06). In this study, we analyzed the observed data comparing the data of Gumi meteorological observatory (GMO). The results showed that the air temperature(relative humidity) of Dongyeong herb garden were lower(higher) than those of GMO. Especially the differences are more during warm climate season. It means that the gaps of thermal environment between two points are mainly caused by the evaporation effects of forest. In addition, we analyzed the warmth indices(warmth index and coldness index) with the observed air temperature. The warmth and coldness indices indicate about 107 and -12, respectively. The values correspond to warm temperature climate.

• Atmosphere
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• v.18 no.4
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• pp.355-365
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• 2008

Synoptic and climatological characteristics of heat waves over Korea and Europe as well as their biometeorological impacts were compared. In July of 1994, excess deaths of about 2,388 in the population of South Korea are estimated by the modified excess death calculation algorithm ofKysely (2004). The excess deaths correspond to the net mortality increase of 12.5% in July of 1994 if we compare the estimated value to the expected number of deaths in this month (i.e., about 19,171). The comparative study of heat waves in Korea and Europe shows that the record-breaking heat waves in both regions are closely associated with prolonged droughts. In particular, reduction of soil moisture, precipitation and cloud cover and enhancement of insolation during the drought periods are very likely to be related to the increase in the intensity and the duration ofheat waves. Climate models predict that the frequency, intensity, and duration of heat waves in the 21 st century will be greatly enhanced in both areas. In order to reduce the biometeorological and socioeconomic impacts due to heat waves, not only the development of heat-related mortality prediction model that can be widely applied to many climate regimes, but also studies on the climatological association between extreme temperatures and abnormal hydrological cycle are needed.

• Journal of the korean society of oceanography
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• v.34 no.2
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• pp.59-72
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• 1999

Cavitating fluid sea ice model of Plato and Hibler (1992) is applied to the Southern Ocean with an idealized, circular Antarctica. Using climatological atmospheric forcing fields averaged in the zonal direction, we show that oceanic heat flux and ice velocity have major effects on the seasonal change of ice edge, as other studies showed. In our model results, there appears a zone of free drift that contains a polynya zone. Thermodynamic forcing functions make dominant contributions to daily increments of ice thickness and compactness, except the zones of ice edge and polynya. The dominant contributions are also shown in distributions of the temperature on ice surface and several to terms in surface heat balance equation, and are also confirmed by those obtained from the thermodynamic-only model with the different locations of ice edge.

• Atmosphere
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• v.30 no.3
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• pp.249-256
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• 2020

We investigate regional differences in the characteristics of cold surges that occurred over the South Korea during winter season (December-February, 1981/1982~2017/2018). A significant regional contrast of cold surge characteristics exists and we found that this is closely related to the spatially inhomogeneous distribution of winter-mean climatological surface temperature in association with the complex topography of the Korean peninsula. For the regions of the temperature below -1℃ (Region1; R1), the frequency of cold surges is inversely proportional to the surface temperature almost linearly. In case of the regions above -1℃ (Region2; R2), cold surge frequency does not exhibit any clear dependency on the surface temperature. Duration and number of occurrences of cold surge between the two regions showed clear difference. Dynamical evolution of cold surges before the onset showed a sharp contrast between R1 and R2. In R1, cold surface air temperature (SAT) was already predominant over East-Asia before the onset and the cold temperature was sustained after the occurrence. On the contrary, warm SAT was predominant over East-Asia before the onset in R2. The SAT suddenly drops just after the cold surge occurrence. We present different origin of wave activity and propagation characteristics between the two types: Wave-activity flux (WAF) was relatively weaker and wave disturbances moved eastward in R1 along with the WAF mainly directing eastward. In case of R2, WAF was stronger and directing southeastward in the upstream of South Korea movement erasing predominant warmer air eventually causing sudden temperature drops over southern provinces over South Korea.

• Journal of Astronomy and Space Sciences
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• v.19 no.1
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• pp.75-88
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• 2002

The climatological characteristics of the polar ionosphere is examined in terms of the ionospheric conductance and electric field. For this purpose, 109 days of measurements from the Sondrestrom incoherent scatter radar are utilized. By combining these two quantities, it is possible to deduce the overhead ionospheric current distributions. The ionospheric current density thus obtained is compared with the corresponding ground magnetic disturbance. Also examined is the effect of the field-aligned current on the ground magnetic disturbance, particularly on the D component Several interesting climatological characteristics about the ionosphere over the Sonderstrom are apparent from this study. (1) The conductance distribution is mainly due to solar EUV radiation during day-time On the other hand, the conductance distribution during the night-time is very low. (2) The conductance distribution one. the polar cap region during the day-time is controlled mostly by the solar EUV radiation, while it is extremely low during night-time wish the Hall and Pedersen conductances being 1.6 and 1.2 siemen, respectively (3) The region of the maximum N-S electric field tend to locate in the dayside sector. The E-W component of the electric field is stronger than that over Chatanika (4) The E-W auroal inospheric current (J/sub E/) is more important in the sunlit hemisphere than the night hemisphere. And a strong southward current is noted in the prenoon sector (5) There is a significant correlation between the overhead ionospheric current and the simultaneously observed ground magnetic disturbance. However, the assumption for the infinite sheet current approximation is far from realistic, underestimating the current density. And the correlation between ${\Delta}H$ and J/sub E/ is higher than the one between ${\Delta}D$ and J/sub N/ , indicating that field-aligned current affects significantly ${\Delta}D$.

• Atmosphere
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• v.20 no.3
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• pp.239-246
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• 2010

In this study, the climatological characteristics of the landfall typhoons on North Korea are surveyed to estimate the frequency, the intensity, the track, and their damage. The data for the period of 1951-2008 are used from both RSMC (Regional Specialized Meteorological Center) Tokyo Typhoon Center and NCEP/NCAR (National Centers for Environmental Prediction/National Center for Atmospheric Research), EM-DAT (Emergency Events Database). There are the ten highest frequencies from 1961 to 1965 and is one frequency for the period of both 1966-1979 and 1976-1980 respectively. Even if a clear trend on the frequency of typhoon is not defined, it is noticeable the intensity has been weak since the frequency of TS (Tropical Storm) decreased. In order to figure out both the characteristic of intensity and the relation between the typhoon track and the expansion of North Pacific High (NPH), Typhoon's tracks are classified into three types as follows: (I) landing on the west coast of North Korea through the mainland of China, (II) landing on the west coast of North Korea, (III) landing on a central/eastern part of the Korean peninsula through South Korea. More often than not, the characteristic of Type (I) is the case of a landfall after it becomes extratropical cyclone. Type(II) and Type(III) show a landfall as TS grade, by comparision. On the relation between the typhoon's track and the expansion of NPH analyzed, Type (I) shows the westward expansion while both Type (II) and Type (III) show the northward expansion and development of NPH. This means the intensity of a typhoon landfall on North Korea is variable depending on the development of NPH. Finally, only two cases are found among total five cases in EM-DAT, reportedly that North Korea was damaged. And therefore, the damage by the wind of Prapiroon (the $12^{th}$ typhoon, 2000) and heavy rainfall with Rusa (the $15^{th}$ typhoon, 2002) landing on North Korea was analyzed. Moreover, it is estimated both Prapiroon and Rusa have done badly damaged to North Korea as the economical losses of as much as six billion and five hundred-thousand US dollar, respectively.