.[1] We examine the direct effect of anthropogenic sulfate aerosol from China on the sea surface temperature (SST) variability in the North Pacific, especially focusing on the Pacific Decadal Oscillation (PDO) using a coupled general circulation model (CGCM). We conduct two long-term simulations, i.e., the Exp_Asia and the Exp_Asia_2x. Anthropogenic sulfate aerosols are prescribed in China only in the Exp_Asia. The conditions for the Exp_Asia_2x simulation are the same as in the Exp_Asia simulation, except the concentration of the anthropogenic sulfate aerosols in China is two times higher than that of the Exp_Asia simulation. It is found that the spatial structure of the PDO changes slightly despite an increase in the anthropogenic sulfate aerosol in China. In contrast, the temporal structure of the PDO is significantly altered between the two simulations. The variance in the PDO index in the boreal winter (December-JanuaryFebruary) and spring (March-April-May) is enhanced for the Exp_Asia_2x on low-frequency timescales (>10 years) compared to that of the Exp_Asia simulation. Upon further analysis, the results of our study indicate that the change in the PDO index from the Exp_Asia to the Exp_Asia_2x is associated with the change in the mean SST in the Kuroshio-Oyashio Extension (KOE) region through the modification of atmospheric circulation. The change in SST in the KOE region is primarily associated with a wave-like temperature structure forced by the diabatic cooling in the low-level atmosphere in China through the modification of atmospheric circulation, which is caused by an increase in the anthropogenic sulfate aerosols. Therefore, it is possible for the temporal structure of the North Pacific SST variability (i.e., PDO) to be altered through the mean SST change in the North Pacific Ocean caused by an increase in regional sulfate aerosols in China.

We examine the meteorological responses due to the probable eruption of Mt. Baekdu using an off-line Climate-Chemistry model that is composed of the National Center for Atmospheric Research (NCAR) Climate Atmosphere Model version 3 (CAM3) and a global chemistry transport model (GEOS-Chem). Using the aerosol dataset from the GEOS-Chem driven by GEOS-5 meteorology, experiment and control simulations of the climate model are performed and their meteorological differences between the two simulations are analyzed. The magnitudes of volcanic eruption and column injection height were presumably set to 1/200 of the Mt. Pinatubo eruption and 9 km, respectively. Significant temperature drop in the lower troposphere (850 hPa), which is mainly due to a direct effect of prescribed volcanic aerosols from Mt. Baekdu, has been simulated up to about −4 K. The upper atmosphere (150 hPa) right above the volcano, however, shows significant warming due to the absorption of the infrared radiation by volcanic aerosols. As a result of the volcanic eruption in the climate model, wave-like patterns are shown in both the geopotential height and horizontal wind. The changes in the lower atmospheric temperature are well associated with the modification of the atmospheric circulation through the hydrostatic balance. In spite of limitations in our current simulations due to several underlying assumptions, our results could give a clue to understanding the meteorological impacts from Mt. Baekdu eruptions that are currently attracting considerable public attention.

Yacon (Smallanthussonchifolius) is a root crop that contains high amounts of fructo-oligosaccharides (FOS). FOS has a sweet taste, is low in calories, and is known to promote intestinal tract health. In this study, various yacon concentrates were substituted for sugar in white pan bread to obtain healthy benefits from the use of FOS. The quality characteristic changes during storage of the white pan breadswith 0, 25, 50, 75 and 100% of added yacon concentrates instead of sugar were investigated. During storage, the water contents and water activities of the breads made with high amounts of yacon concentrates changed less than in those made with only sugar. The hardness and chewiness of the breads made with high amounts of yacon concentrates had lower values than those made with only sugar. Thus, bread made with yacon concentrates might exhibit increased moisture retention and decreased aging velocity. The substitution of yacon concentrates for sugar in pan bread improved the bread quality.