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Based on the high-resolution data from April to October (the warm season) during the 2010 to 2020 timeframe provided by the FY-2F geostationary meteorological satellite, the classification and application evaluation of the eastward-moving southwest vortex cloud system affecting Zhejiang Province was conducted using cloud classification (CLC) and black body temperature (TBB) products. The results show that: (1) when the intensity of the eastward-moving southwest vortex is strong, the formed precipitation is predominantly regional convective precipitation. The cloud system in the center and southeast quadrant of the southwest vortex is dominated by cumulonimbus and dense cirrus clouds with convective precipitation, while the other quadrants are mainly composed of stratiform clouds, resulting in stable precipitation; (2) The original text is modified as follows: By using the TBB threshold method to identify stratiform and mixed cloud rainfall, we observed a deviation of one order of magnitude. This deviation is advantageous for moderate rain. However, the precipitation results from mixed clouds identified by the TBB threshold method are being overestimated; By means of the application of stratiform and mixed cloud rainfall identified by the TBB threshold method, an order of magnitude deviation was identified (3) The TBB can be consulted to estimate the precipitation, above which there is a large error. Moreover, the dispersion of precipitation produced by deep convective clouds is the largest, while the dispersion of precipitation produced by stratiform clouds is the smallest and has better predictability. Compared to CLC products, cloud type results based on TBB identification are better for convective cloud precipitation application.

To explore the influence of complex terrain on wind characteristics of the surface layer and to better develop and utilize wind energy resources of high-altitude regions in central and western China, two typical topographies: the Qiaodi Village in Sichuan (in western China, site 1) and the Nanhua Mountain in Shanxi (in central China, site 2), were selected for this study. The diurnal and monthly variations of the atmospheric stability were contrasted at the two sites, according to the Obukhov length calculated by the eddy covariance data. The energy exchange process between complex underlying surfaces and the atmospheric boundary layer can be reflected to a certain extent by investigating the diurnal variation differences of the turbulent fluxes at the two sites. The results show that: (1) the dominant boundary layer at site 1 during nighttime is the neutral boundary layer, while at site 2 it is the stable; (2) the horizontal wind speed at 10 m above the ground is the highest (lowest) in the neutral (unstable) boundary layer at site 1, while it is the highest (lowest) in the neutral and weak-unstable (stable) boundary layer at site 2, and (3) the momentum flux, sensible heat flux, and latent heat flux all show unimodal diurnal characteristics. There is a 1 h lag in the flux peak at site 1 compared to site 2.

The Tibetan Plateau (TP) vortex (TPV), one of the crucial weather systems triggering rainfall, plays a key role in modulating precipitation over TP and downstream regions. The role of atmospheric heat source in TPV development is explored by a case study in June 2016, using high-resolution ERA5 reanalysis, black-body temperature (TBB) obtained from the Fengyun-2E (FY-2E) satellite, and precipitation amount from the Tropical Rainfall Measurement Mission (TRMM). The evolutions of TPV can be split into three stages, i.e., generation, development, and pre-moving-off stage. The intensity of TPV increases with fluctuations, with weaker and shallower TPV in the generation stage, strongest in the development stage and deepest in the pre-moving-off stage. Importantly, the genesis of TPV is related to the surface warming center driven by surface sensible heating while its development is primarily dependent on the latent heat of condensation. The main contributor of the latent heat of condensation is further analyzed as a vertical transport of the water vapor that promotes TPV development.