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Tropical cyclone (TC) induced precipitation (TCP) over Japan is evaluated with the rain gauge observation based gridded dataset APHRO_JP. The TC-influenced frequency reaches a maximum in the Nansei Islands and decreases monotonically with latitude. On the other hand, the distribution of TCP indicates different characteristics from the one of TC-influenced frequency. The largest annual TCP, 500 mm yr-1 or more, occurs over eastern Kyushu (E-Kyushu), southern Shikoku (S-Shikoku), and the eastern Kii peninsula (E-Kii), where it accounts for 15% or more of the total precipitation. The maximum daily TCP amounts to 200 mm d-1 in those three areas, which are all located on the eastern side of Japan and correspond to eastward or southeastward topographic inclines. A significant relationship is found between the amount of annual TCP and topographic incline, and the large amount of TCP concentrates in the eastward or the southeastward inclines. The extreme daily TCP once every 50 years is also evaluated. The extreme daily TCP is estimated to be 500 mm d-1 comparable to the climatological annual TCP in E-Kyushu, S-Shikoku, and E-Kii. These three areas appear to be the most hazardous part of Japan in terms of TCP. [ABSTRACT FROM AUTHOR]

As the Tibetan Plateau (TP) is an important Asian water resource, future changes in precipitation over the TP are an essential part of climate change assessments for the TP and surrounding regions. Here we investigate the water budget over the TP with a global 20-km grid atmospheric general circulation model. Future simulations are performed using CMIP5 multi-model ensemble mean sea surface temperature changes at the end of the 21st century under the RCP8.5 scenario. In the present climate, an east-west contrast in the water budget is noted: over the eastern TP, both moisture flux convergence and local evaporation contribute to summertime precipitation with comparable magnitude; on the other hand, over the western TP, contribution from local evaporation dominates. Under the future climate, precipitation increases over the TP. Contribution from increasing evaporation dominates that from increasing moisture flux convergence into the TP. A prominent east-west contrast is also found in future surface water budget changes. Over the western TP, surface temperature increases are higher, an increasing rate of precipitation is greater, soil moisture becomes wetter, and runoff increases more than over the eastern TP. This suggests that the east-west contrast in surface climate over the TP could become smaller in the future. [ABSTRACT FROM AUTHOR]

Background: Forecasting bud physiologic conditions can help 'Fuji' apple farmers manage their orchards more efficiently. Being able to determine the nature of a bud before bud burst is one such forecast that could be of use to these 'Fuji' growers. The aim of this research project was to determine if a device, a visible/near-infrared spectrometer, could be employed to determine whether a bud is a flower or non-flower bud without destroying the bud. Methods: Experiments were conducted on buds taken from a 'Fuji' apple tree, beginning on January 29 through to March 31, 2021, three days before bud burst. The data from the visible/near-infrared spectrometer clarified whether a bud was a flower or a non-flower bud. The Spectro data Classification Learner App proved to be an accurate classification method to analyze flower and non-flower bud Spectro data. Result: Three days before bud burst, the chlorophyll content levels of the non-flower buds were markedly higher (P≤0.05) than those of the flower bud, which explains why the visible border of the near-infrared spectrometer might have been changed by the chlorophyll content of buds. The visible and near-infrared bands of the buds showed that the Spectro data of the non-flower buds were higher than those of the flower buds when measurements were made three days before bud burst. Three days before bud burst Cubic KNN of KNN classifier analyzed flower and non-flower buds smoothly. Spectro data were labeled as accuracy 75.9%, sensitivity 86% and specificity 67%. The results that were obtained suggest that farmers could use a visible/near-infrared spectrometer to identify flower and non-flower buds in their orchards, without damaging the buds, three days before bud burst. [ABSTRACT FROM AUTHOR]

Typhoon Mireille (1991) caused devastation over Japan. Assessing the impacts of such an extreme typhoon under global warming is an important task to prevent and mitigate future natural disasters. This study investigated the influences of global warming on the strong winds of Typhoon Mireille by conducting pseudo-global warming (PGW) experiments with a regional model. Since significant damages to forest areas occurred in Kyushu and Tohoku, we compared the typhoon impacts in these two regions. It was demonstrated that on average the mean wind speeds induced by Typhoon Mireille become stronger in Kyushu and weaker in Tohoku under the PGW conditions than under the September 1991 conditions. The difference between the two regions in the future is due to the simulated typhoons under PGW being stronger at lower latitudes and weakening more rapidly at higher latitudes. Thus, the impacts of Typhoon Mireille under a warmed climate are considered to be more severe at a lower latitude and weaker at a higher latitude. [ABSTRACT FROM AUTHOR]

This study numerically investigates the influences of global warming on Typhoon Vera (1959) by conducting pseudo-global warming experiments. It was found that the intensity of Typhoon Vera will be stronger in warmed climate conditions than in the actual September 1959 condition not only at the time of the typhoon's maturity but also at the time of the landfall. Sensitivity experiments indicate that this projected increase in the typhoon intensity is robust, by taking into consideration the effects of the increase in sea surface temperature and temperature lapse rate under global warming. The examination of rainfall characteristics over the Kiso River and the Yodo River basin demonstrated that the maximum accumulated rainfall and the maximum hourly rainfall at a certain location within the region are more intensified in the PGW conditions than in the 1959 condition at their worst levels. Robustness and uncertainty of the projected changes in the typhoon impacts are discussed. [ABSTRACT FROM AUTHOR]

The article discusses the effects of the emissions of greenhouse gases on the change in climate and the plans of adjusting to global warming. Particular focus is given to the models and methods used for future climate changes, the high-resolution large ensemble's benefits, and the results of the study conducted.

Among marine toxins, tetrodotoxin (TTX) and paralytic shellfish poisons (PSPs) are known as notorious neurotoxins that induce serious food poisoning incidents in the Southeast Asia region. The aim of this study was to investigate whether TTX and PSP toxins are important issues of seafood safety. Paralytic toxicity was observed in mice exposed to 34 specimens from five species of gastropods using a PSP bioassay. Five species of gastropods, Natica vitellus, Natica tumidus, Oliva hirasei, Oliva lignaria, and Oliva annulata, were collected from the coastal seawaters in Nha Trang City, Vietnam, between August 2007 and October 2007. The average lethal potency of gastropod specimens was 90 ± 40 (mean ± standard deviation) mouse units (MU) for N. vitellus, 64 ± 19 MU for N. tumidus, 42 ± 28 MU for O. hirasei, 51 ± 17 MU for O. lignaria, and 39 ± 18 MU for O. annulata. All toxic extracts from the sample species were clarified using a C18 Sep-Pak solid-phase extraction column and a microcentrifuge filter prior to analysis. High-performance liquid chromatography coupled with fluorescence detection indicated that the toxins of the olive shell (O. hirasei, O. lignaria, and O. annulata) were mainly composed of saxitoxin (STX) (73–82%), gonyautoxin (GTX) 2, 3 (12–22%), and minor levels of TTX (5–6%). The toxins of N. vitellus and N. tumidus were mainly composed of STX (76–81%) and GTX 1, 4 (19–24%). Furthermore, liquid chromatography–tandem mass spectrometry analysis was used to verify the identity of the PSPs and TTX. Our evidence shows that these gastropods have novel toxin profiles. [ABSTRACT FROM AUTHOR]