• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.51 no.2
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• pp.212-220
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• 2015

We examined the appearance of cold water in the southwest region of the East Sea, based on the sea surface temperature (SST) at the east coast of Korea and buoy data in Donghae ($37^{\circ}31$'N, $130^{\circ}00$'E, 80 km east away from Donghae port) and Pohang ($36^{\circ}21$'N, $129^{\circ}46$'E, 35 km east away from Ganggu port) from June to August in 2013. Also, the serial oceanographic data of National Fisheries Research and Development Institute (NFRDI) were used to see the oceanographic conditions for June and August in 2013. The SST anomaly at the east coast showed negative values in $3{\sim}6^{\circ}C$ from 2 July. At Janggigab, the SST anomaly showed negative value amount to $10^{\circ}C$ in 8 July. The negative values of SST anomaly continued to the middle of August at Janggigab. The wind speed was 6~11 m/s and the direction was south-southwestly in 1 July. The wind speed amounts to 6~16 m/s in 2 July. It means that the strong wind induced the upwelling effect by a day. The temperature was lower than normal at the depth in 20 m of the East Sea in June and August. The air pressure was 996~998 hPa in the beginning of July. It was the lowest air pressure during the studied period. The correlation was 0.3 between the SST anomaly and air pressure. It was suggested that the appearance of cold water in the East Sea was influenced by a stirring due to wind and low air pressure as well as coastal upwelling.

• Journal of the Korean earth science society
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• v.45 no.1
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• pp.37-47
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• 2024

In the summer of 2018, the Korea-Japan (KJ) region experienced an extremely severe and prolonged heatwave. This study examines the GloSea6 model's prediction performance for the 2018 KJ heatwave event and investigates how its prediction skill is related to large-scale circulation patterns identified by the k-means clustering method. Cluster 1 pattern is characterized by a KJ high-pressure anomaly, Cluster 2 pattern is distinguished by an Eastern European high-pressure anomaly, and Cluster 3 pattern is associated with a Pacific-Japan pattern-like anomaly. By analyzing the spatial correlation coefficients between these three identified circulation patterns and GloSea6 predictions, we assessed the contribution of each circulation pattern to the heatwave lifecycle. Our results show that the Eastern European high-pressure pattern, in particular, plays a significant role in predicting the evolution of the development and peak phases of the 2018 KJ heatwave approximately two weeks in advance. Furthermore, this study suggests that an accurate representation of large-scale atmospheric circulations in upstream regions is a key factor in seasonal forecast models for improving the predictability of extreme weather events, such as the 2018 KJ heatwave.

• Journal of the Korean association of regional geographers
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• v.2 no.2
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• pp.93-102
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• 1996

The Korean Peninsula is located on the east coast of monsoon Asia of the midlatitude, where the Pacific polar front moves. As a result variations of spatial and temporal distribution of precipitation occur. A great variation of precipitation during the summer months created frequent droughts and floods. The purpose of this study is to identify distributional characteristics and to analyze synopic characteristics of summer droughts in Korea. The research methods used are ; (1) to identify droughts based on the anomaly of monthly precipitation during summer of 1994. (2) to analyze correlations between drought and weather systems by using the calender of rain days. (3) to compare a synoptic mechanism of summer droughts with that of typical normal summer. The characteristics of summer droughts of 1994 may be summarized as follows ; 1) While most regions were affected by the droughts some regions displayed specific characteristics. The southern part of the Korean Peninsula was severely affected during the month of June. August droughts severely affected east part of the Sobek Mountains, thus showing that the droughts of June and August are highly localized. 2) In the pressure anomaly of surface field. the positive anomaly appears in June around Korean Peninsula, but in July when all parts of the South Korea were under severe droughts, the anomaly changes and becomes negative. 3) Extracyclones occurred less frequently in the summer of 1994. Those that did occur were located in areas far off the Korean Peninsula having little consequences on the drought patterns. 4) The trough of westerly wave at 500hPa height patterns in June is located far from the eastern sea of Korean Peninsula, but in July and August Korean Peninsula belongs to ridge of westerly wave. 5) In June the positive height anomaly at 500hPa surface appears zonally from Siberia to the western Parts of North Pacific Ocean, and in July and August, the strong positive anomaly appears around Korean Peninsula. As a result the zonal index of westerlies at during each month of summer in Korean sector has a large value, which in turn implies that drought will prevails when zonal flow is strong.

• Journal of Chest Surgery
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• v.25 no.9
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• pp.925-929
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• 1992

Supravalvular aortic stenosis is relatively uncommon form of congenital heart disease and the most important lesion of this anomaly is various narrowing of the aortic lumen just above the sinus of Valsalva. We experienced a case of hourglass type of supravalvular aortic stenosis involving lcm from length from lcm above the sinus of Valsalva. The patient was associated with mental retardation, peculiar facies and dental anomaly. The diagnosis was confirmed preoperatively by retrograde left heart catheterization and left ventriculography. An incision was made in the ascending aorta and into the right coronary and noncornary sinus. Care was taken to protect the right coronary artery. A Y-shaped patch of Dacron was made to enlarge the stenotic portion of aorta. Postoperative pressure gradient between the aorta and left ventricle markedly reduced 36 mmHg in comparison with preoperative pressure gradient 150mmHg. The boy was discharged without any event.

• Korean Journal of Remote Sensing
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• v.11 no.2
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• pp.29-42
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• 1995

A typhoon center location and its intensity from the 54.96GMz channel of Microwave Sounding Unit(MSU) on board the NOAA satellite is analyzed. NOAA satellite MSU channel 3 data may delineate the development and dissipation of the upper tropospheric warm core associated with a typhoon. The typhoon warm core is related to microwave imagery of 250hPa temperature field (54.96GMz). The typhoon center intensity, surface center pressure and maximum wind speed at the eye well, correlate to horozontal Laplacian of an upper tropospheric temperature field. The typhoon center is found from the analysis of 250hPa temperature field. The excellent correlation is found between the horizontal Laplacian of an tropospheric temperature field and surface maximum wind speed, another correlation is found between the warm temperature anomaly and surface pressure anomaly.

• Journal of the Korean Geographical Society
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• v.45 no.3
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• pp.319-341
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• 2010

The purposes of this study are to classify heavy snowfall types in the Republic of Korea based on fresh snowfall data and atmospheric circulation data during the last 36(1973/74-2008/09) snow seasons and to identify typical surface synoptic climate patterns that characterize each heavy snowfall type. Four synoptic climate categories and seventeen regional heavy snowfall types are classified based on sea level pressure/surface wind vector patterns in East Asia and frequent spatial clustering patterns of heavy snowfall in the Republic of Korea, respectively. Composite analyses of multiple surface synoptic weather charts demonstrate that the locations and intensity of pressure/wind vector mean and anomaly cores in East Asia differentiate each regional heavy snowfall type in Korea. These differences in synoptic climatic fields are primarily associated with the surge of the Siberian high pressure system and the appearance of low pressure systems over the Korean Peninsula. In terms of hemispheric atmospheric circulation, synoptic climatic patterns in the negative mode of winter Arctic Oscillation (AO) are also associated with frequent heavy snowfall in the Republic of Korea at seasonal scales. These results from long-term synoptic climatic data could contribute to improvement of short-range or seasonal prediction of regional heavy snowfall.

• Journal of Chest Surgery
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• v.25 no.5
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• pp.469-479
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• 1992

Searching for the clinical effects of colloid solutions that used to increasing the oncotic pressure of priming solutions at the cardiopulmonary bypass, 29 patients [who were diagnosised as simple VSD around 10kg of body weight and scheduled to be operated from June 1990 to December 1990 at Sejong General Hospital] were divided randomly and prospectively to the two groups: A group [15] was received 4gm% albumin as addition to the priming solutions and B Group [14] the same amount of Ringer`s lactated solution. 34 clinical parameters [Body weight, sex, age, body surface area, Qp/Qs, pulmonary arterial pressure, cardiopulmonary bypass time, anesthetic time, intraoperatively infused crystalloid and colloid amount, hemoglobin, hematocrit, serum sodium concentration, serum osmolarity, urine osmolarity, urine specific gravity, serum concentration, serum osmolarity, urine osmolarity, urine specific gravity, serum protein, serum albumin concentration, urine output, central venous pressure, postoperatively infused colloid amount, immedediate post-operative peak inspiratory pressure, cardiac index, blood pressure and pump flow during cardiopulmonary bypass, inotro-pic assist, diuretics, extubation period, total drain amount, duration of ICU] were measured and compaired between the two groups. There were no differences of preoperative and operative clinical parameters. And postoper-atively, practically there were no nearly differences at the clinical outcomes between the two groups, but some parameters [cardiac index, PIP, BP and pumpflow during CPB, etc] contributed to being preferable to the Group A at certain times [P<0.05]. Conclusively, it might be thought that the priming solution of cardiopulmonary bypass added by colloid solution had some beneficial effects on the patients, especially younger and associated with complex anomaly to be expected taken longer time of cardiopulmonary bypass, and more studies about the neonatal and complex anomaly cases were needed in that points.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.992-996
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• 2008

In this study, changes in precipitation across South Korea during snow seasons (November-April) and their potential are examined. Current (1973/74-2006/07) and future (2081-2100) time series of snow indices including snow season, snow-to-precipitation ratio, and snow impossible day are extracted from observed snow and precipitation data for 61 weather stations as well as observed and modeled daily temperature data. Analyses of linear trends reveal that snow seasons have shortened by 3-13 days/decade; that the snow-to-precipitation ratio (the percentage of snow days relative to precipitation days) has decreased by 4-8 %/decade. These changes are associated with pronounced formations of a positive pressure anomaly core over East Asia during the positive Arctic Oscillation winter years since the late 1980s. A snow-temperature statistical model demonstrates that the warming due to the positive core winter intensifies changes from snow to rain at the rate of $4.7cm/^{\circ}C$. The high pressure anomaly pattern has also contributed to decreases of air-sea thermal gradient which are associated with the reduction of snow could formation. Modeled data predict that a fingerprint of wintertime global warming causing changes from snow to rain will continue to be observed over the 21st century.

• Atmosphere
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• v.22 no.4
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• pp.449-454
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• 2012

This study presents the long-term variability of spring precipitation over the Korean peninsula. It is found that the significant interdecadal change in the spring precipitation has occurred around year 1991. Over the Korean peninsula the precipitation for the post-1991 period increased by about 30 mm per year in CMAP and station-measured data compared to the precipitation prior to year 1991. Due to an increased baroclinicity during the later period, the low-level negative pressure anomaly has developed with its center over northern Japan. Korea is situated at the western end of the negative pressure anomaly, receiving moisture from westerly winds and producing more precipitation. Also, we estimate the change in the near future (years 2020~2040) spring precipitation using six best performing Coupled Model Intercomparison Project 3 (CMIP3) models. These best model ensemble mean shows that spring precipitation is anticipated to increase by about 4% due to the strengthened westerlies accompanied by the northwestern enhancement of the North Pacific subtropical high.

• Journal of the Korean association of regional geographers
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• v.4 no.1
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• pp.43-56
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• 1998

The purpose of this study is to identify distributional characteristics of climatic elements and to analyze synoptic characteristics on the pressure fields for spring droughts in Korea. In the distributions of minimum temperature during the spring droughts, positive anomalies and negative anomalies are mixed up, but in March the negative anomaly areas are widely distributed in Korea. It implies that the droughts of March have more frequent occurrences of the west-high, east-low pressure patterns. In the maximum air temperatures, the positive anomalies appear in Korea. It indicates that the spring droughts have rain days, cloud amount and humidities less than normal. As a result, the amount of evaporation is increased in Korea. In the pressure anomaly of surface pressure fields, the positive anomalies appear in the west, negative anomalies in the east in March, but in May the positive anomalies appeared zonally around the Korean peninsula. It indicates that March droughts have more frequent occurrences of the west-high. east-low patterns, but in May the Korean Peninsula has more frequent recurrences of the migratory anticyclone patterns. The height anomaly patterns of 500hPa pressure surface in spring droughts are similarly shown to those of surface fields. In March droughts, the positive height anomalies appear in the west, the negative height anomalies in the east, but in April the negative height anomaly areas are extended to the west part. In May the positive anomalies appear zonally around the Korean Peninsula, and strong positive height anomalies appear around the Kamchatka Peninsula and the sea of Okhotsk. These are the result of circulations that inhibit the eastward movement of westerlies and that has persistent anticyclone circulation patterns around the Korean Peninsula. As a result, the zonal indices of westerlies during March and April droughts are lower than normal, but higher in May. These data indicate that early spring droughts are associated with weak zonal flow, but the late spring droughts are obviously related with strong zonal flow. In addition, during early spring droughts the abnormally deep trough over the west coast of the North Pacific Ocean that accompanied the anticyclone was associated with frequent advection of air from the dry regions in the Central Asia into the Korean Peninsula. The atmospheric circulation patterns at the height of the 500hPa pressure surface in May was quite different from March and April circulation patterns. Instead of the abnormal ridge in the west and trough in the east, the circulation pattern in May was characterized by a much stronger than normal anticyclone over the Korean Peninsula. Also, the zonal indices of westerlies in May are higher than normal. The occurrences of drought in early spring, therefore, have mechanism different from those of late spring.