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721.
722.
Data from high-resolution satellites were used to evaluate the spatial and temporal distribution of mesoscale convective vortices (MCVs) in central and east China and the western Pacific Ocean region. The monthly variation in MCVs was significant. From May to October, MCVs were clearly affected by large-scale environmental conditions, including the South Asian summer monsoon, subtropical high and solar radiation, which resulted in clear changes in MCV spatial distributions from strengthening and weakening processes. Based on the analysis of diurnal MCV variations and the precipitation rate from May to October, MCVs were found to occur more frequently over the ocean than over land. MCVs near the Sea of Japan and northern South China Sea occurred during all types of weather. Ocean occurrences near land, such as the Ryukyu Islands, were categorized as morning-active MCVs. The hilly regions of southeastern China and North China Plain were characterized by afternoon-active MCVs. Limited to topography and the urban heat island effect, the Beijing-Tianjin-Tangshan area had evening-active MCVs, while Changbai Mountain had nocturnal MCVs. 相似文献
723.
724.
L. J. Janssen P. Woitke O. Herbort M. Min K. L. Chubb Ch. Helling L. Carone 《Astronomische Nachrichten》2023,344(10):e20230075
The first JWST observations of hot Jupiters showed an unexpected detection of SO in their hydrogen-rich atmospheres. We investigate how much sulfur can be expected in the atmospheres of rocky exoplanets and which sulfur molecules can be expected to be most abundant and detectable by transmission spectroscopy. We run thermochemical equilibrium models at the crust–atmosphere interface, considering surface temperatures 500–5000 K, surface pressures 1–100 bar, and various sets of element abundances based on common rock compositions. Between 1000 and 2000 K, we find gaseous sulfur concentrations of up to 25% above the rock in our models. SO , SO, H S, and S are by far the most abundant sulfur molecules. SO shows potentially detectable features in transmission spectra at about 4 m, between 7 and 8 m, and beyond 15 m. In contrast, the sometimes abundant H S molecule is difficult to detect in these spectra, which are mostly dominated by H O and CO . Although the molecule PS only occurs with concentrations ppm, it can cause a strong absorption feature between 0.3 and 0.65 m in some of our models for high surface pressures. The detection of sulfur molecules would enable a better characterization of the planetary surface. 相似文献