SST Ensemble Experiment-Based Impact Assessment of Climate Change on Storm Surge Caused by Pseudo-Global Warming: Case Study of Typhoon Vera in 1959

金沢大学理工研究域環境デザイン学系To evaluate future changes in storm surge caused by global warming, dynamical downscaling was conducted using the Weather Research and Forecasting model for Typhoon Vera under present- and future-climate conditions and storm surge simulation using the Coupled Model of Surge, Wave, and Tide. The present-climate experiment entailed dynamical downscaling using data from the Japanese 55-year Reanalysis project as the initial and boundary conditions, and the future-climate experiments entailed downscaling considering future changes simulated through sea-surface temperature ensemble experiments using the Meteorological Research Institute Atmosphere General Circulation Model. The characteristics of the downscaled typhoon agreed well with the Best Track, and the future changes in the typhoon characteristics were as follows: intensification of the central pressure, delayed decline in the high-latitude area, and westward track migration. Present-climate storm surge simulation executed using these downscaling results after correcting for the track error agreed with the observed surge, but the storm surges under future-climate conditions were underestimated because of differences in the typhoon track and surface roughness. Storm surge simulations were conducted using an empirical typhoon model; the results suggest a storm surge of 26cm (average of the ensemble) at Nagoya Port, which is located in the innermost region of Ise Bay. © 2017 World Scientific Publishing Company.Embargo Period 12 month

伊勢湾台風を対象とした高潮追算のためのJRA55再解析データの力学的ダウンスケール

金沢大学理工研究域環境デザイン学系Dynamical downscaling experiment of JRA55 for Typhoon Vera (Isewan Typhoon) using WRF was carried out. At First, the reproducivilities of five global reanalysis data for Typhoon Vera were compered, and it was shown that JRA55 has highest quality. There are some papers of the dynamic downscaling method for storm surge hindcast. In this study, domain size and resolution of the coarse domain were considered. The coarse domain size influences the typhoon route and central pressure, and large domain estimates large error of typhoon route and stronge typhoon. Threshold is whether the coarse domain fully includes the area of wind speed more than 15 m/s around the typhoon. On the other hand, the resolution of the coarse domain doesn\u27t affect the typhoon route, and affect the typhoon strength.伊勢湾台風を対象に，最新の全球再解析気象データJRA55を用いたWRFによるダウンスケール実験を行った．伊勢湾台風が発生した1959年を含む全球気象データは限られており，その再現性は低いことが知られている．そこで，5種の全球気象データから伊勢湾台風を抽出，比較して，JRA55の再現性の高さを示した．また，高潮追算の外力である海面気圧及び海上風を高解像度で計算するための領域気象モデルの台風経路から計算領域端までの幅と水平解像度について手法の検討を行った．計算領域サイズの設定は，台風経路と台風強度の両者に影響し，領域を広く設定するほど台風経路は誤差が大きく，台風強度は強く推定された．水平解像度の違いは台風経路への影響が小さく，高解像度ほど台風強度を強く推定することがわかった．以上の結果を踏まえて，高潮推算における領域気象モデルの検討手順を示した.出版者照会後に全文公

Low Surface Potential with Glycoconjugates Determines Insect Cell Adhesion at Room Temperature

Cell-coupled field-effect transistor (FET) biosensors have attracted considerable attention because of their high sensitivity to biomolecules. The use of insect cells (Sf21) as a core sensor element is advantageous due to their stable adhesion to sensors at room temperature. Although visualization of the insect cell-substrate interface leads to logical amplification of signals, the spatiotemporal processes at the interfaces have not yet been elucidated. We quantitatively monitored the adhesion dynamics of Sf21 using interference reflection microscopy (IRM). Specific adhesion signatures with ring-like patches along the cellular periphery were detected. A combination of zeta potential measurements and lectin staining identified specific glycoconjugates with low electrostatic potentials. The ring-like structures were disrupted after cholesterol depletion, suggesting a raft domain along the cell periphery. Our results indicate dynamic and asymmetric cell adhesion is due to low electrostatic repulsion with fluidic sugar rafts. We envision the logical design of cell-sensor interfaces with an electrical model that accounts for actual adhesion interfaces.Matsuzaki T., Terutsuki D., Sato S., et al. Low Surface Potential with Glycoconjugates Determines Insect Cell Adhesion at Room Temperature. Journal of Physical Chemistry Letters 2022 13(40), 9494-9500. DOI: 10.1021/acs.jpclett.2c01673. Copyright © 2022 American Chemical Society

伊勢湾台風の擬似温暖化実験による将来高潮の予測

金沢大学理工研究域環境デザイン学系Dynamical downscaling targeted typhhon Vera under pseudo-global warming (PGW) that was based on JRA-55 and SST ensemble experiments using MRI-AGCM3.2S was carried out. Future change parameter sensitivity analysis of SST, air temperature and air pressure gave results that PGW experiment by only SST made typhoon to strengthen excesively (decrease 40 hPa in minimum pressure) and taking air temperature and pressure in account made typhoon minimum pressure to dexrease 10 hPa. Every PGW experiment made typhoon route to shift to west. Storm surge simulation using empirical typhoon model estimated surge level raise of 26 cm on ensemble average.水平解像度20kmのMRI-AGCM3.2SによるSSTアンサンブル実験結果から海面温度，気温，気圧の将来変化量を見積り，JRA-55に将来変化量を上乗せすることで擬似温暖化環境を作成し，JRA-55と擬似温暖化環境を初期・境界値として伊勢湾台風を対象とした力学的ダウンスケーリングを行い台風と高潮の将来変化について検討した．その結果，海面温度を考慮するだけでは過度に強い台風（中心気圧で約40hPaの低下）を推定し，気温，気圧を考慮することで台風の中心気圧が現在気候に比べて約10hPa小さくなること，台風経路が西へシフトすることを確認した．ダウンスケーリング結果から台風情報を抽出して経験的台風モデルによる高潮計算を行った結果，将来気候下では平均して約26cmの高潮偏差の上昇が推定された.出版者照会後に全文公

Long-term impacts of ocean wave-dependent roughness on global climate systems

Ocean surface waves can play an active role in climate systems, but they are often ignored in Global Climate Models (GCMs). Wave-dependent surface roughness was implemented within the Atmospheric GCM (MRI-AGCM) using the spectral wave model WAVEWATCH III. Two types of wave-dependent roughness, due to wave steepness and to wave age, were considered. Climate simulations with wave-dependent roughness were compared to simulations with just wind speed-dependent roughness. In climate simulation with wave steepness-dependent roughness, the spatial distribution of roughness is correlated to that of swell dominance. In simulation with wave age-dependent roughness, the spatial distribution of roughness is correlated to that of wind direction stationarity. Both simulations show reduced roughness in the tropics, which leads to an enhancement of surface wind speeds by up to 15%; these enhanced wind speeds are closer to observations compared with the baseline simulation with just wind speed-dependent roughness. We find that the reduced roughness and the enhanced wind speeds in the tropics lead to significant changes in atmospheric circulation, as in Hadley circulation and precipitation. The characteristic responses of the Hadley circulation and precipitation to changing sea surface roughness are presented