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This study introduces a novel diagnostic method to assess tropical atmosphere‐ocean coupling, using a two‐dimensional plane defined by the 90‐day high‐pass‐filtered sea surface temperature (SST) and column water vapor (CWV). The method was applied to reanalysis data and high‐resolution coupled atmosphere‐ocean simulation data. In the Indo–Pacific warm pool region, the phase relationship between SST and CWV remained consistent across both reanalysis and simulation data sets. However, differences in the temporal evolution of these variables were observed in the central Pacific region. The heat budget analysis results indicate that the differences between the two data sets in the central Pacific are related to variations in the effects of atmospheric disturbances on SST. This study demonstrates the potential of our novel diagnostic method for evaluating atmosphere–ocean coupling in climate models. Weather disturbances in the tropics develop from the interaction between the ocean and the atmosphere. We can use climate models to investigate the impact of this interaction, but we need other methods to evaluate the interaction itself. In this study, we develop a new way to understand how the atmosphere and the ocean interact in the tropics. We achieve this by focusing on changes over time in the sea surface temperature and the amount of water vapor in the air. We found that these changes happen at different rates in different regions of the ocean. We also found that a climate model failed to capture these changes in some regions. Our new method improves our understanding of the atmosphere and ocean interaction and teaches us how to improve climate models. A novel analysis method was developed to illustrate regional differences in the atmosphere‐ocean coupling across tropical oceansThe application of this diagnostic method to the reanalysis and coupled model data revealed differences in the central Pacific regionThrough heat budget analysis, we proposed distinct processes by which atmospheric disturbances change the sea surface temperatures A novel analysis method was developed to illustrate regional differences in the atmosphere‐ocean coupling across tropical oceans The application of this diagnostic method to the reanalysis and coupled model data revealed differences in the central Pacific region Through heat budget analysis, we proposed distinct processes by which atmospheric disturbances change the sea surface temperatures

Extratropical cyclones, major contributors to precipitation in the midlatitudes, comprise mesoscale fronts and fine‐scale convective storms. Intense oceanic cyclones pose natural hazards, making reliable projections of their changes with global warming of great interest. Here, we analyze the first ever global climate simulations to resolve such mesoscale dynamics of extratropical cyclones. The present‐day structure, frequency, and precipitation of the oceanic extratropical cyclones compare well with reanalyses and new satellite datasets that resolve the multiscale cloud‐precipitation system. Simulated precipitation from intense oceanic cyclones increases at a rate of 7%/K1, following Clausius‐Clapeyron, with warming. The same scaling is apparent also in the interhemispheric contrast, suggesting that the latter could serve as a predictor of the former. Projected changes in precipitation from intense oceanic cyclones with warming may thus be testable using a reliable global observation network of precipitation in the present day. Precipitation in midlatitudes is strongly governed by extratropical cyclones. Its future change is of great societal concern for adaptation to a warmer world. In this study, we use a new kind of global model and a new satellite dataset to resolve fine‐scale and frontal features of cyclones and their changes with warming. The simulation shows that the amount of precipitation around the intense oceanic cyclones will increase due to global warming, and furthermore, the rate of precipitation change around the intense oceanic cyclones is closely related to the precipitation contrast between the northern and southern hemispheres in the present climate. This suggests that the future precipitation change associated with intense oceanic cyclones could be inferred from the difference between the northern and southern hemispheres in the present climate. The first global climate simulations to explicitly represent the mesoscale dynamics of extratropical cyclones are analyzedPrecipitation from intense cyclones scales with temperatures across hemispheres and with global warming following Clausius‐ClapeyronProjected change in precipitation from intense cyclones may thus be testable using global observations of precipitation in the present day

Extreme El Niño events affect the number of intense tropical cyclones (ITCs) over the western North Pacific (WNP). In 1997 and 2015, both extreme El Niño years, ITC numbers were above normal in the WNP. In order to clarify how, and to what extent, sea surface temperature anomaly (SSTA) distributions control the ITCs genesis, the authors conducted 50‐member ensemble simulations using a high‐resolution global nonhydrostatic model that explicitly simulates ITCs. The ensemble simulations showed a clear relationship between the number of ITCs and their genesis locations in the WNP. However, the authors found that the simulated numbers of ITCs in the WNP were also closely related to the strength of the monsoon trough, which varies under given SSTA conditions. This indicates that reliable seasonal forecasting of ITCs depends on our ability to accurately reproduce the monsoon trough, whose strength is modulated mainly by internal atmospheric variability but also by SSTA. Tropical cyclone has a potential to cause great loss of life and damage to infrastructure. Accurate prediction of tropical cyclone activity can reduce these loss and damage. However, deterministic prediction of tropical cyclone is difficult. Development of tropical cyclones is affected by sea surface temperature and its geographical distribution (e.g., El Niño). To evaluate variability of intense tropical cyclone activity, we conducted 50‐member simulations under an identical sea surface temperature condition. Although the simulation shows the number of intense tropical cyclones differs among members despite the identical sea surface condition, the number is strongly related to the atmospheric response to the sea surface temperature. Over the western North Pacific, the monsoon trough is strongly contributing to tropical cyclone genesis and its genesis location. The simulated number was correlated with the strength of westerly wind associated with the monsoon trough. The response of the monsoon trough to the sea surface temperature itself also shows variations. However, the response was partially predictable by the sea surface temperature. This study shows that the reproducibility of the monsoon trough plays a key role in reliable seasonal forecasting of intense tropical cyclones. Fifty‐member ensemble simulations of 1997 and 2015 assessed the impact of El Niño on intense tropical cyclones in the western North PacificThe intense tropical cyclone numbers substantially varied among ensemble members, despite their use of identical sea surface temperatureThe strength of westerly wind associated with the monsoon trough played a key role in predicting the number of intense tropical cyclones

We applied multiple relayed COSY and 2D homonuclear Hartman-Hahn spectroscopy to globoside, a glycolipid purified from human red blood cells. The subspectra corresponding to individual sugar components were extracted even from overlapping proton resonances by taking the cross sections of 2D spectra parallel to the F 2axis at anomeric proton resonances, so that unambiguous assignments of sugar proton resonances were accomplished.

We applied ID homonuclear Hartmann-Hahn (1D-HOHAHA) and difference NOE experiments to determine the chemical structure of Forssman's antigen, a glycolipid purified from sheep red blood cells. The subspectra corresponding to the individual sugar components were extracted from overlapping proton resonances by selective excitation of the anomeric proton resonances, so that unambiguous assignments of the sugar proton resonances were accomplished. Then, difference NOE experiments were performed to determine the linkage of the sugar units. The present procedure was found to be useful for the structure determination of glycoconjugates and also reduces the amount of samples and machine time.

We applied multiple relayed COSY and 2D homonuclear Hartman‐Hahn spectroscopy to globoside, a glycolipid purified from human red blood cells. The subspectra corresponding to individual sugar components were extracted even from overlapping proton resonances by taking the cross sections of 2D spectra parallel to the F2axis at anomeric proton resonances, so that unambiguous assignments of sugar proton resonances were accomplished.

We applied ID homonuclear Hartmann‐Hahn (1D‐HOHAHA) and difference NOE experiments to determine the chemical structure of Forssman's antigen, a glycolipid purified from sheep red blood cells. The subspectra corresponding to the individual sugar components were extracted from overlapping proton resonances by selective excitation of the anomeric proton resonances, so that unambiguous assignments of the sugar proton resonances were accomplished. Then, difference NOE experiments were performed to determine the linkage of the sugar units. The present procedure was found to be useful for the structure determination of glycoconjugates and also reduces the amount of samples and machine time.

The coverage dependence of desorption behavior of n-alkanethiol monolayers on Au(111) has been studied using thermal desorption spectroscopy (TDS) together with scanning tunneling microscopy (STM) to investigate the molecule−substrate interactions. STM observations indicated four different phases during the growth. We present for the first time evidence for a drastic coverage-dependent change of desorption species, which is parallel with a structure change from a low-density phase to a denser phase:  while the thiolates in the latter phase bimolecularly desorb as disulfides, those in the former phase unimolecularly desorb as thiolate radicals.