This study (1) explored spatio-temporal population distribution patterns in Jeonju by using emerging hot spot analysis and (2) identified the influential factors to determine the spatio-temporal patterns by using multinomial logit model. The major findings are as follows. First, the results of emerging hot spot analysis indicated that the 100*100m grid in the urban area of Jeonju was found to have a category of hot spots, whereas most of the cold spot series was concentrated in the outskirts of the city. Also, new towns such as Jeonju Eco City, Jeonbuk Innovation City, and Hyocheon District were persistent or intensifying hot spots, Third, the results of multinomial logit model revealed that the factors influencing deterrmining the spatio-temporal patterns were accessibility to schools, hospitals, parks, and walfare services. This study offered a deeper understanding of urbanization and regional changes in Jeonju, and important information for urban planning.

이 연구는 팬데믹(pandemic) 전후 국제항공여객 운송시장을 대상으로 항공편 운항에 의한 CO2 배출 특성과 변화를 체계적으 로 파악하는 것을 주요 목적으로 한다. 이를 위해 2019년과 2021년 2분기 전 세계 국제여객 항공편 스케줄 데이터를 기반으로 ICAO(International Civil Aviation Organization)의 CERT(CO2 Estimation and Reporting Tool) 인벤토리를 이용하여 노선 단위의 CO2 배출량을 추정한 후, 노선의 대권 거리와 항공기의 크기를 기준으로 구분된 하부시장에 따른 CO2 배출량과 배출 효율성의 분포와 변화를 비교분석하였다. 주요 분석 결과는 다음과 같다. 첫째, 2021년 2분기 전 세계 국제항공여객 운송시장의 CO2 배출량은 약 31.6백만 톤으로 추정되었으며. 2019년 동 분기(117.95백만 톤) 대비 약 73.21% 감소하였다. 두 시기 모두 5,000km 이상의 장거리 시장, 그리고 100~400석 항공기 운용 시장에서의 배출량 비중이 높게 나타났다. 다만 팬데믹 기간에는 5,000km 이상, 그리고 400석 이상 항공기 시장에서 CO2 배출량의 감소가 두드러지게 나타났다. 둘째, 2021년 2분기 시장의 CO2 배출 효율성은 2019년 동 분기 대비 약 4% 향상되었다. 두 시기 모두 노선의 대권 거리와 항공기의 크기가 증가할수록 배출 효율성이 감소하는 경향이 존재하였으며, 팬데믹 기간 중 일부 하부시장에서는 구형 및 초대형 기종들의 운항 감축(혹은 중단)이 두드러짐에 따라 배출 효율성이 향상되기도 하였다. 마지막으로 팬데믹 전후 주요 국제노선들의 CO2 배출 효율성 변화를 탐색한 결과, 글로벌 허브 공항들을 연결하는 대륙 간 장거리 노선들을 중심으로 효율성이 낮게 나타난 반면, 차상위 계층 공항들과 연결된 일부 노선들, 그리고 동남아･동북아의 주요 공항들을 연결하는 역내 노선들은 상대적으로 효율성이 높게 나타났다. 본 연구는 팬데믹 전후 전 세계 국제항공여객 운송시장의 운영 실적과 CO2 배출에 대한 세부 특성과 변화를 실증적으로 분석했다는 점에서 의의가 있다.

We conducted a seasonal field survey to analyze the distribution patterns of a phytoplankton community and biological oceanographic characteristics in the Geum river estuary in 2018. The results showed that the phytoplankton community consisted of 58 genera and 116 species, showing a relatively simple distribution. It was controlled by diatoms at 70.2%, a low number of species in winter and spring, and a high number in summer and autumn. The phytoplankton cell density ranged from 10.0 to 2,904.0 cells mL-1, with an average layer of 577.2 cells mL-1, which was low in autumn and high in winter. The seasonal succession of phytoplankton dominant species was mainly centric diatoms from winter to summer, including Thalassiosira nordenskioeldii, Cerataulina bergonii, and Skeletonema costatum-ls in winter, S. costatum-ls and C. bergonii in spring, and Eucampia zodiacus and Th. nordenskioeldii in summer. However, the autumn species depended upon the regions, with the inner bay dominated by the centric diatom, Aulacoseira cf. granulata, the mixed areas by S. costatum-ls, and the open sea by the dinoflagellate, Lingulodinium polyedra. According to principal component analysis (PCA), the phytoplankton community was greatly affected by the inflow and expansion of freshwater, including high nutrients, which are introduced annually through the rivermouth weir in Geum river estuary. However, the estuary, which is strongly affected by annual freshwater, was limited to areas near Geumran Island, which is adjacent to the river-mouth weir.

한강수계 남한강의 보 (강천보, 여주보, 이포보) 공사 후 수변부 여울 구간의 물리적 환경의 변화에 따른 유수성 저서동물의 군집 변화를 확인한 결과 다음과 같은 결론을 얻었다. 첫째, 보에 의한 여울구간의 소실은 유속, 하상 등 물리적 환경의 변화를 야기하여 수질요인과는 독립적으로 수생태계에 영향을 미칠 수 있다. 둘째, 남한강 보 구간의 수변부 물리적 서식환경의 복합적인 변화는 유수성 분류군의 군집구성에 영향을 미친 것으로 판단된다. 셋째, 저서성 대형무척추동물 유수성 지표 후보종 157 분류군은 수생태계 변화의 원인 분석을 비롯한 하천 수생태계 복원 및 재자연화 등에 유용한 지표로 활용될 수 있을 것으로 기대된다. 넷째, 향후 유속변화에 대한 수생태계 영향을 면밀하게 파악하기 위해서는 분류군별 유속에 대한 저항성 또는 선호도를 바탕으로 한 지표연구가 필요할 것으로 사료된다.

The purpose of this study is to elucidate the spatio-temporal characteristics of ultrafine dust generation in East Asia and the synoptic climate patterns related to its dispersal which has its adverse effects on public health across East Asia. To achieve this purpose, Level 3 monthly Aerosol Optical Depth (AOD) data extracted from MODIS satellite imagery (MOD08_M3) representing particle matters less than 2.5 micrometer (PM2.5) and the NCEP-NCAR reanalysis I upper-level climatic data associated with the exacerbation of ultrafine dust problem are analyzed for the recent 20-year (2001-2020) period. Analyses of long-term average MOD08 data show that high AOD value exceeding 0.5 or more frequently occurred in populous cities in East Asia but mainly in the vicinity of densely populated large rivers and the eastern lowlands in China between mid-winter and mid-spring, which is attributable to the accumulation effects of continuous fossil fuel consumption for heating and manufacturing. Despite the overall decreasing trend of ultrafine dust across China in the 2010s, the weakened westerlies in the warmer climate as well as its continuous generation from the densely populated industrial regions of China provide a favorable synoptic climate condition for frequent severe ultrafine dust problems across East Asia including South Korea. These results indicate that ultrafine dust from China is a long-lasting transboundary environmental problem across East Asia, which needs long-term international cooperation in developing the sustainable policies.

The purpose of this study is to explore spatio-temporal patterns of extreme low human-sensible temperature (HST) across Mt Halla (1,950m), Korea. To do this, decadal (2011/12-2020/21) averages of daily or hourly windchill index (WCI), which quantifies HST considering the combined effects of low temperature and strong wind, are calculated for 24 weather stations in Mt Halla. Time series of decadal average daily mean show that extreme low HST events with moderate risk level (-27~-10°C) occur in mid-winter (mid-January~early February) around the high mountainous areas of Mt Halla, while such risk does not exist in the low-elevated coastal regions of Jeju Island under subtropical climate. Strong wind around the subalpine climate belt lowers HST by 5°C than air temperature in mid-winter. In extreme cases when the advection of northerly cold wind is intensified by the west high-east low pressure pattern in East Asia, the HST around the peak of Mt Halla can be lowered to high risk level (-39~-28°C) in the early morning times of mid-winter days. These information about mountain bioclimate may help establish mountain extreme climate warning systems, which are needed to protect mountaineers from potential life-threatening accidents caused by extreme low HST events over high mountains such as Mt Halla.

In this study, the spatio-temporal patterns of summertime thermal environments in the two subtropical cities (Jeju and Seogwipo) of Jeju Island, Korea are examined. Long-term average data from Jeju and Seogwipo show that higher human sensible temperature (HST) than air temperature (T) due to the high humidity effects associated with warm sea surface temperature around Jeju Island is most distinct during mid-summer period (late July-early August). Comparatively, their trend analyses reveal that summertime intra-seasonal changes with more increasing HST than T are most obviously observed in late summer (late September-early October) and regionally in Seogwipo. According to the hourly temperature-humidity data measured at approximately 30 HOBO temperature-humidity sensors deployed in the two subtropical cities during 2019 summer, the greater HST than T during mid-summer period maximizes up to 6.2°C and 7.0°C across the urban areas of Jeju and Seogwipo, respectively in early afternoon, leading to consecutive inter-daily heat wave events. The examination of their spatial patterns demonstrates that bioclimatic heat waves in these two subtropical cities are affected primarily by the urban heat island phenomenon. However, it should not be overlooked that local moisture advection from the warm ocean adjacent to the subtropical cities can modify the stronger heat wave pattern toward urban cores. It is also notable that according to comparisons of local HST and T distributions between impervious urban cores and neighboring urban parks, not only the size of green space but also other ecological properties including species of vegetation may be crucial factors to the mitigation of hot thermal environments in subtropical cities during summers.