Pantala flavescens is a dominant Odonata species in the rice fields in Korea. To determine the effects of different temperatures on its larval growth and emergence, field and laboratory experiments were conducted. Larval growth was also monitored in mono-cropping and double-cropping rice fields. The growth of larvae was monitored every week by measuring the head width. In the field experiment, no difference was found in larval growth and emergence between the control temperature and +1.9°C of the control temperature. The larval growth was greater at 23°C than at 20°C laboratory temperatures, and no emergence was recorded at either temperature after eight weeks of monitoring. There was a quadratic relationship between larval growth and temperature in an incubator at five temperature regimes of 15, 20, 25, 30, and 35°C. Midseason water drainage caused the extinction of the existing individuals and newly hatched larvae dominated after re-watering in the rice fields. Larval size was greater in double-cropping fields than in mono-cropping fields in late July but the tendency was reversed in early August. The results of this study suggest that temperature warming will directly promote the larval growth of P. flavescens and indirectly influence seasonal growth via changes in water management in rice fields.

The mean global surface temperatures have increased since the late 19th century by approximately 0.3-0.6 o C (IPCC, 2007). The linear warming trend over the last 50 years is nearly double that of the last 100 years. The impact of climate warming on insects was studied using the southern green stink bug Nezara viridula as a model insect. This bug is known as a cosmopolitan agricultural pest that damages diverse crop plants worldwide. Effects of climate warming on insects include distribution, abundance, phenology, voltinism, physiology, behaviour, and community structure. It should be noted here that climate warming affects insects not only directly but also indirectly through interaction of species in ecosystem. 1. Northward range expansion of N. viridula in Japan. Past and current limits of the distribution range of N. viridula were compared (Tougou et al., 2009). It was found that the climate warming promoted northward range expansion of N. viridula by providing favourable overwintering conditions close to the specie’s range limit. The past and the current limits of the distribution range of N. viridula in central Japan were investigated. In the early 1960s, the northern limit of the species’ range was in Wakayama Prefecture and was limited by a +5 o C isothermal line for the mean January temperature. Forty five years later (2006–2007), a new survey in Wakayama and five neighbouring prefectures demonstrated that this northern limit shifted northward by 85km, at a rate of 19.0km/decade. The shift northward was likely promoted by milder winter conditions. The mean January–February temperature in the region was 1.03–1.91ºC higher in 1998–2007 than in 1960–1969. In the 1960s, the mean January temperature exceeded +5 ºC only in Wakayama city, but by now it has surpassed +5 ºC in Osaka and Tsu cities, located further north (52 and 59 km respectively), which corresponds to the current distribution of N. viridula. The number of cold days (with mean temperature below +5ºC) also significantly decreased, while the annual lowest temperature significantly increased. N. viridula was found mostly at or close to those locations where (1) the mean January temperature exceeded +5ºC, (2) the mean number of cold days did not exceed 26 during January–February, and (3) where the mean annual lowest temperature did not drop below –3.0 ºC. The general linear model shows that the mean January temperature and number of cold days are the most important factors controlling the northern limit of distribution of N. viridula. All the climatic data suggest that over the last 45 years environmental conditions have become more favourable for overwintering of N.viridula at many locations in central Japan. This has likely promoted the northward spread of the species, representing the direct response of the species to climate warming. A sympatrically distributed congeneric N. antennata is responding to the warming by retreat from the ocean coast towards cooler elevated habitats, which might be a complex response to elevated temperature and interspecific mating with N. viridula. This range expansion of N. viridula is now accelerating the extinction of N. antennata by the infertile interspecific copulation. 2. Ecophysiological responses of N. viridula to simulated warming. The effect of simulated climate change on N. viridula was studied close to the species’ northern range limit in Japan (Musolin et al., 2010). Insects from the same egg masses were reared for 15 months in 10 consecutive series under quasi-natural (i.e. outdoor) conditions and in a transparent incubator, in which climate warming was simulated by adding 2.5ºC to the outdoor temperature. The warming strongly affected all life-history and phenological parameters. In the spring, the simulated warming advanced the timing of body colour changes and post-diapause reproduction. In the early summer, it increased egg production and accelerated nymphal development. In the late summer (the hottest season), the effect of the simulated warming was strongly deleterious: nymphs developed slowly, suffered higher mortality and had difficulties during final moulting; the emerged females were smaller, some exhibited abnormal cuticle, produced fewer eggs and had a decreased life span. Our current studies are going to clarify that such an adverse effect of high temperature is caused by the decrease in bacterial symbiont which is harboured in the midgut of stink bugs. As in many phytophagous heteropteran species, N. viridula possesses a number of sac-like outgrowths, called crypts, in a posterior section of the midgut, wherein a specific bacterial symbiont is harbored. In previous studies on N. viridula from Hawaiian populations, experimental elimination of the symbiont caused little fitness defects in the host insect (Prado, et.al., 2006, Prado et al., 2009). N. viridula from Japanese populations consistently harbor the same gammaproteobacterial gut symbiont. However, in this case, contrary to the previous works, experimental sterilization of the symbiont resulted in severe nymphal mortality, indicating an obligate host-symbiont relationship (Tada et al., 2011). Considering the worldwide host-symbiont association and those experimental data, N. viridula is considered to be generally and obligatorily associated with the gut symbiont, while the symbiont effect on the host performance may be different among geographic populations. In the autumn, the warming accelerated nymphal development, resulted in larger female size, affected the timing of the diapause-associated adult body colour change from green to russet and enhanced preparation for overwintering. Larger females had higher winter survival rate than smaller females. The warming strongly increased survival rate in both size classes and allowed smaller females to reach the same winter survival rate as larger females had under the quasi-natural conditions. The winter survival also differed between the green and dark-coloured females under the quasi-natural, but not under the warming conditions. However, under the warming conditions, green females survived the winter even better than dark-coloured females did under the quasi-natural conditions. Moreover, the warming shortened the life span of females from the summer generations and prolonged it in those from the autumn generation. It is concluded that even a moderate temperature increase (+2.5 ºC) in the future is likely to have a complex influence upon insects, strongly affecting many of their life-history and phenological parameters.

Distributions of ants are mainly dependent on temperature. Hence, global warming would lead to shifts of distribution and abundance in ants. We surveyed ants at 366 forest sampling sites in South Korea using pitfall traps to predict change of ant abundance. Abundances of ant species were projected on the projected temperature based on A1B climate scenario. Common species (> 10 % occurrence) were analyzed on the relationship between abundance and temperature, and 16 species of the common species were selected for projection of abundance owing to future climate warming. Abundance of the selected species were projected on 900 m2 grid cells in 2011 and 2060 using GIS tool. In the projection, 11 species are predicted to decrease in 2060, whereas 5 species are predicted to increase. Myrmica kotokui, a most dominant highland species is expected to decrease up to 2.5% of current abundance in 2060, whereas Pachycondyla chinensis is expected to increase up to 264%. This abrupt change of ants would lead to cascade effects on other organisms such as insects, plants, mushrooms, and birds, which would disturb various functions and services of forest ecosystems.

Insect occurrence is closed related to crop and environment. Global climate changes as environment factor influencing not only crops but also insects on their behavior, distribution, development, survival and reproduction. Insect life stage are most often calculated using accumulated degree days from base temperature and biofix point. Temperature is also main factor to changes in moisture humidity and CO2 that effect on crop and insect development. Precipitation is another climate change on consideration factor to insect survival. Therefore, the precise impacts of climate change on insects is somewhat uncertain because it may change favor some insects while others may inhibit their development. On predicting the impact of climate change on insect is very complex exercise and need closed cooperation with experts on modeling. Some generalized predictions can be made, based on current pest distributions and severity of insect outbreaks in individual regions. At the present in Thailand, some alien insect species often present by global trades as by climate change.

This study had two main objectives. We first investigated which weather phenomena people were most concerned about in the context of climate change or global warming. Then, we conducted content analysis to find which words were more commonly used with climate change or global warming. For this, we collected web data from Twitter, Naver, and Daum from April to October 2019 in the Republic of Korea. The results suggested that people were more concerned about air quality, followed by typhoons and heat waves. Because this study only considered one warm period in the year of 2019, winter-related weather phenomena such as cold wave and snowfall were not well captured. From Twitter, we were able to find wider range of terminologies and thoughts/opinions than Naver and Daum. Also, more life-relevant weather events such as typhoons and heat waves in Twitter were commonly mentioned compared to Naver and Daum. On the other hand, the comments from Naver and Daum showed relatively narrower and limited terms and thoughts/ opinions. Especially, most of the comments were influenced by headlines of articles. We found many comments about air quality and energy/economic policy. We hope this paper could provide background information about how to promote the climate change education and public awareness and how to efficiently interact with general audiences.

지난 25년간 지구온난화로 인한 국내 기후변화 양상은 지역 간에 차이가 있어, 고온지역은 평균온도의 증가를 보이지는 않았으나, 최저기온의 지속적인 상승과 그에 따른 열대야 발생을 확인할 수 있었다. 또한 그로 인한 젖소의 고온스트레스 발생, 섭취량의 감소 및 생산성 저하가 예상된다. 저온지역의 경우에는 여름철 평균온도 및 최저온도의 상승으로 인해 연평균기온이 유의적으로 상승한 반면, 겨울철에는 오히려 최저기온의 지속적인 하강이 관찰됨에 따라 동물의 저온스트레스가 가중될 것으로 예상된다. 착유우가 저온스트레스 상태에 있을 때는 에너지요구량과 건물섭취량이 증가하여 생산 효율이 떨어지며, 사료효율의 감소로 경제성은 감소되고 우유 생산비는 증가한다. 특히, 극심한 저온스트레스 또는 사료, 음수 및 우사바닥의 결빙은 섭취량 감소를 야기하며 이에 따른 생산성의 저하는 더욱 가중될 것으로 예상된다. 결론적으로 지구온난화로 인한 기후변화에 따른 지역별 영향은 다르며, 온도 스트레스에 의한 낙농우의 생산성 저하를 최소화하고, 동물의 복지와 건강을 증진시키기 위해서는 지역별 기후변화 특성에 맞춘 사양기술의 개발이 필요하다.