• 대한지리학회지
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• 제39권1호
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• pp.13-26
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• 2004

본 연구는 상대적 날씨 스트레스 지수로 NET의 적용 가능성을 파악하고자 하였다. 기상청에서 예보하고 있는 기온, 습도, 바람 자료를 이용하여 NET 값의 시공간적 분포 특성을 분석하였다. 여름철 스트레스 지수인 일 최고 NET의 지역별 스트레스 기준값은 바람과 습도보다는 기온의 영향을 받으므로 일 최고 기온의 분포와 유사하다. 겨울철 스트레스 지수인 일 최저 NET의 스트레스 기준값은 산지 지역과 서울 이북 지역에서는 낮은 기온의 영향을. 해안 지역에서는 강한 바람의 영향으로 기준값이 여름철에 비하여 다양하게 나타난다. 스트레스가 강한 날의 발생 빈도는 여름철은 뚜렷한 연변화가 나타나지 않지만, 겨울철에는 1990년대 중반 이후 뚜렷한 증가 경향을 보인다.

• 한국농공학회논문집
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• 제61권3호
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• pp.1-14
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• 2019

North Korea has frequently suffered from extreme agricultural crop droughts, which have led to food shortages, according to the Food and Agriculture Organization (FAO). The increasing frequency of extreme droughts, due to global warming and climate change, has increased the importance of enhancing the national capacity for drought management. Historically, a meteorological drought index based on data collected from weather stations has been widely used. But it has limitations in terms of the distribution of weather stations and the spatial pattern of drought impacts. Satellite-based data can be obtained with the same accuracy and at regular intervals, and is useful for long-term change analysis and environmental monitoring and wide area access in time and space. The Evaporative Stress Index (ESI), a satellite-based drought index using the ratio of potential and actual evaporation, is being used to detect drought response as a index of the droughts occurring rapidly over short periods of time. It is more accurate and provides faster analysis of drought conditions compared to the Standardized Precipitation Index (SPI), and the Palmer Drought Severity Index (PDSI). In this study, we analyze drought events during 2015-2017 in North Korea using the ESI satellite-based drought index to determine drought response by comparing with it with the SPI and SPEI drought indices.

• 한국환경과학회지
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• 제26권12호
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• pp.1399-1405
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• 2017

We compared the spatial distribution of several heat stress indices (the Wet-Bulb Globe Temperature(WBGT) index, Environmental Stress Index (ESI), and Modified Discomfort Index(MDI)) for the heat wave of June 6~August 26, 2016, in Daegu. We calculated the heat stress indices using data from the high density urban climate observation network in Daegu. The observation system was established in February. 2013. We used data from a total of 38 air temperature observation points (23 thermometers and 18 automatic weather stations). The values of the heat stress indices indicated that the danger level was very high from 0900-2000h in downtown Daegu. The daily maximum value of the WBGT was greater than or equal to $35^{\circ}C$. The differences in the heat stress indices from downtown and rural areas were higher in the daytime than at nighttime. The maximum difference was about 4 before and after 1400h, and the time variations of the heat stress indices corresponded well. Thus, we were able to confirm that the ESI and MDI can be substituted with the WBGT index.

• 대한인간공학회지
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• 제36권1호
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• pp.23-36
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• 2017

Objective: This paper presents a study to evaluate the WBGT index for assessing the effects of a wide range of outdoor weather conditions on human responses. Background: The Wet Bulb Globe Temperature (WBGT) index was firstly developed for the assessment of hot outdoor conditions. It is a recognised index that is used world-wide. It may be useful over a range of outdoor conditions and not just for hot climates. Method: Four group experiments, involving people performing a light stepping activity, were conducted to determine human responses to outside conditions in the U.K. They were conducted in September 2007 (autumn), December 2007 (winter), March 2008 (spring) and June 2008 (summer). Environmental measurements included WBGT, air temperature, radiant temperature (including solar load), humidity and wind speed all measured at 1.2m above the ground, as well as weather data measured by a standard weather station at 3m to 4m above the ground. Participants' physiological and subjective responses were measured. When the overall results of the four seasons are considered, WBGT provided a strong prediction of physiological responses as well as subjective responses if aural temperature, heart rate and sweat production were measured. Results: WBGT is appropriate to predict thermal strain on a large group of ordinary people in moderate conditions. Consideration should be given to include the WBGT index in warning systems for a wide range of weather conditions. However, the WBGT overestimated physiological responses of subjects. In addition, tenfold Borg's RPE was significantly different with heart rate measured for the four conditions except autumn (p<0.05). Physiological and subjective responses over 60 minutes consistently showed a similar tendency in the relationships with the $WBGT_{head}$ and $WBGT_{abdomen}$. Conclusion: It was found that either $WBGT_{head}$ or $WBGT_{abdomen}$ could be measured if a measurement should be conducted at only one height. The relationship between the WBGT values and weather station data was also investigated. There was a significant relationship between WBGT values at the position of a person and weather station data. For UK daytime weather conditions ranging from an average air temperature of $6^{\circ}C$ to $21^{\circ}C$ with mean radiant temperatures of up to $57^{\circ}C$, the WBGT index could be used as a simple thermal index to indicate the effects of weather on people. Application: The result of evaluation of WBGT might help to develop the smart clothing for workers in industrial sites and improve the work environment in terms of considering workers' wellness.

• Journal of Animal Science and Technology
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• 제65권2호
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• pp.324-335
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• 2023

Korea, located in East Asia in the northern hemisphere, is experiencing severe climate changes. Specifically, the heat stress caused by global warming is negatively affecting the dairy sector, including milk production and reproductive performance, as the major dairy cattle Holstein-Friesian is particularly susceptible to heat stress. Here, we collected artificial insemination and pregnancy data of the Holstein and the Jersey cows from a dairy farm from 2014 to 2021 and analyzed the association between the conception rate and the temperature-humidity index, calculated using the data from the closest official weather station. As the temperature-humidity index threshold increased, the conception rate gradually decreased. However, this decrease was steeper in the Holstein breed than in the Jersey one at a temperature-humidity index threshold of 75. To evaluate the effects of heat stress on the oocyte quality, we examined the nuclear and cytoplasmic maturation of Holstein (n = 158, obtained from six animals) and Jersey oocytes (n = 123, obtained from six animals), obtained by ovum pick-up. There were no differences in the nuclear maturation between the different conditions (heat stress: 40.5℃, non- heat stress: 37.5℃) or breeds, although the Holstein oocytes seemed to have a lower metaphase II development (p = 0.0521) after in vitro maturation under heat stress conditions. However, we found that the Holstein metaphase II oocytes exposed to heat stress presented more reactive oxygen species and a peripheral distribution of the mitochondria, compared to those of the Jersey cattle. Here, we show that weather information from local meteorological stations can be used to calculate the temperature-humidity index threshold at which heat stress influences the conception rate, and that the Jersey cows are more tolerant to heat stress in terms of their conception rate at a temperature-humidity index over 75. The lower fertility of the Holstein cows is likely attributed to impaired cytoplasmic maturation induced by heat stress. Thus, the Jersey cows can be a good breed for the sustainability of dairy farms for addressing climate changes in South Korea, as they are more resistant to hyperthermia.

• 한국수자원학회논문집
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• 제36권5호
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• pp.839-849
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• 2003

가뭄은 주요 자연 재해 중의 하나이다. 가뭄 파악을 위하여 주로 강우량과 같은 기상자료를 주요 입력 자료로 활용하여 분석하고 있으나 이러한 기상 자료는 한정된 기상 관측소로부터 얻어진 점자료에 해당된다. 따라서, 기상자료를 이용한 분석에서는 시간적 혹은 공간적으로 원하는 자료의 제공이 원활하게 이루어지지 않을 수 있다. 원격탐사 자료는 가뭄분석을 위하여 기상자료에서 포착할 수 없는 이러한 문제점을 보완하기 위한 자료로 활용될 수 있다. 따라서, 본 연구에서는NOAA 위성에 탑재되어 있는 AVHRR 센서로부터 얻어지는 자료를 이용하여 가뭄 파악을 위한 분석을 실시하였다. 특히 본 연구에서는 NOAA/AVHRR로부터 얻어진 식생지수(NDVI)와 이로부터 얻을 수 있는 식생상태지수(VCI)를 이용하여 가뭄 분석을 실시하였으며, 이들 지수는 가뭄으로부터 기인된 식생 스트레스를 파악하는데 유용하게 이용될 수 있음을 알 수 있었다. 본 연구를 통하여 가뭄에 대한 시간적, 공간적 특성을 파악하는데 위성자료가 유용하게 이용될 수 있음을 알 수 있었으며, VCI를 통하여 가뭄 지역도 작성이 가능함을 보여주고 있다.

• 대한원격탐사학회지
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• 제38권2호
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• pp.179-188
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• 2022

지구온난화는 기후변화를 야기하며 전지구적으로 이상기상 현상을 유발하고 있다. 우리나라에서도 폭염, 가뭄과 같은 이상기상 현상이 증가하고 있는 상황이다. 이상기상 감시를 위하여 지표면온도(Land Surface Temperature, LST), 온도상태지수(Temperature Condition Index, TCI), 식생활력지수(Normalized Difference Vegetation Index, NDVI), 식생상태지수(Vegetation Condition Index, VCI), 식생건강지수(Vegetation Health Index, VHI) 등의 위성자료가 활용되고 있다. TCI와 VCI를 이용하여 계산되는 VHI는 온도, 강수와 같은 기상 요인에 의한 식생 스트레스를 나타내며, 기후변화 상황에서 가뭄 평가에 주로 활용되고 있다. TCI, VCI는 날짜 및 장소에 따른 LST, NDVI의 과거 평년치를 참조해서 산출되기 때문에, 아직 2년여의 자료밖에 없는 천리안위성 2A호(GK2A) AMI (Advanced Meteorological Imager) 자료로부터 TCI, VCI, VHI를 산출하는 것은 현재로서는 쉽지 않은 일이다. 본 연구에서는 대안적인 방법으로 VIIRS (Visible Infrared Imaging Radiometer Suite) 센서의 LST, NDVI를 이용하여 GK2A의 VHI 산출 가능성을 모색하였다. GK2A와 VIIRS의 LST, NDVI는 상당히 높은 상관성을 보이기 때문에, GK2A에 존재하지 않는 과거 평년치를 VIIRS 자료로 대체하는 방식을 택하였다. 8일 간격으로 GK2A 격자에 해당하는 LST, NDVI의 최소·최대값 조견표를 구축하여 TCI, VCI, VHI를 산출하였고, 최근 우리나라 이상기상 현상에 대한 해석을 수행하였다. GK2A VHI는 2020년 3월과 6월의 폭염, 4월과 7월의 저온, 8월의 폭우 등으로 인한 식생 스트레스의 변화를 잘 표현하는 것으로 나타났지만, 미국 해양대기청(National Oceanic and Atmospheric Administration, NOAA)의 VHI 산출물은 그렇지 않았다. 본 연구에서 제시한 GK2A VHI는 향후 LST, NDVI의 과거 평년치에 대한 통계적으로 엄밀한 보완을 거친다면 폭염, 가뭄으로 인한 식생 스트레스 감시에 활용될 수 있을 것으로 사료된다.

• 한국안전학회지
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• 제15권1호
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• pp.112-120
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• 2000

We have compared the regulations of hot environment workpaces between Korea and ACGIH, then pointed out some insufficiences of Korean regulations for occupational hygiene and safety. And investigated the heat stress characteristics of laboratory, lathe and foundry working. The metabolic heat loads of those workplaces were obtained as 120, 300 및 660 kcal/hr based on WBGT index. WBGT index could be depended on weather condition, therefore useful for controlling working and rest times etc, but Belding-hatch index was represented by strength of working, definitely this would be convinient result for arranging countermeasures of workers in hot environments by estimating metabolic heat and signs of fatigue.

• 한국농공학회논문집
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• 제62권5호
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• pp.85-91
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• 2020

In order to calculate the Crop Water Stress Index (CWSI), it is necessary to collect weather data (air temperature, humidity, wind speed and solar radiation) and canopy temperature. However, it is not always available to have necessary data sets for CWSI calculation. Therefore, this study was aimed to develop an easy and simple CWSI equation (CWSI_EE) using only two data, air and canopy temperatures. Infrared sensors and weather sensors were installed on apple and peach trees and nearby a study area and every ten-minute data were collected from June to October in 2018 and 2019, respectively. A relationship between air-canopy temperature difference and CWSI was statistically analyzed and used to develop CWSI_EE using the three dimensional Gaussian model. The performance of CWSI_EE against original CWSI showed R² and NSE to 0.780 and 0.710 for apple trees and R² and NSE to 0.884 and 0.866 for peach trees. This study found that the level of crop water stress could be easily calculated using CWSI_EE with only air and canopy temperature data.

• 한국대기환경학회지
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• 제26권3호
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• pp.253-264
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• 2010

This study investigates the relationship between daily mortality and heat stress in Seoul, using perceived temperatures (PT) derived from a heat budget model. During the summer season, observed PT intensity showed the biggest magnitude of summer heat stress from the middle 10 days of July to the first 10 days of August. The elderly (65 and above) were found to be the most vulnerable to heat stress. The threshold PT, with a significant increase in excess mortality, was $38^{\circ}C$. No time lagged effect was observed with summer heat stress, while a high correlation was observed between anomalies in PT and relative deviation of mortality. A comparison of the heat index and the discomfort index with excess mortality revealed that the discomfort index underestimated excess mortality, whereas the heat index could not appropriately explain the increase in excess mortality correlated with the increase in excess heat. In contrast, PT was found to be the weather element that best represents excess mortality due to heat stress, and is thus expected to serve as a more reliable forecast index of human biometeorology.