Study on wavy distribution of rainfall associated with typhoon Matsa (2005)

Abstract

An analysis is made to investigate the structure features of the extensive heavy rainfall left by typhoon Matsa, after its landfall in mainland China in August 2005, based on a range of observational results, including surface intensive observation data, TBB data from China's FY-2 satellite, and NCEP 1°×1° reanalysis data. The study tries to explore the interaction between atmospheric waves, 3-D atmospheric structures, and typhoon rainbands. Observational facts, diagnostic analysis, and atmospheric wave theory are used to look into the formation mechanism of distant typhoon rainbands. Results show that (1) Matsa rainbands have the features of noticeable wave train distribution and long distance propagation; (2) the typhoon rainbands extend as far as 2000 km northwardly from the typhoon center, with a wavelength of 500-1000 km and a wave period of 12-24 h; (3) the wave structure of Matsa rainbands is closely associated with the corresponding wave variation of the ambient 3-D atmospheric structures, including disturbance vorticity, divergence field, vertical motion field, water vapor flux divergence field, etc. (4) both observational facts and theoretical analysis show that the northward extending typhoon rainbands are associated with the mixed effects of atmospheric inertia wave and internal gravity wave; (5) only under proper atmospheric stratification and vertical wavenumber of gravity wave, can a typhoon stimulate such a wave being able to reach such a distance, and result in extending wavy rainbands.

The Role of Typhoon Songda (2004) in Producing Distantly Located Heavy Rainfall in Japan*

“…Previous studies have mostly focused on precipitation directly caused by a TC either over the open ocean (e.g., Wang and Holland 1996a,b;Rogers et al 2003;Atallah et al 2007) or approaching-making landfall (e.g., Li et al 2007;Kimball 2008;Chen et al 2006). These studies have shown that over the open ocean, the rainfall distribution in a TC is largely controlled by the vertical shear in the large-scale environmental flow and the translation speed of the storm itself; whoever, after landfall, both the rainfall intensity and the radial extent of the outer rainfall are also affected by the soil moisture of the underlying land surface.…”

Discriminant Genetic Algorithm Extended (DGAE) model for seasonal sand and dust storm prediction

“…In the study, cluster analysis [30] was employed to analyze the relationship between the seasonal/interdecadal variations and the abnormal variations in the polar vortex, in an attempt to develop an approach for evaluating and predicting seasonal and annual SDS intensity. Figure 1 shows 100 hPa anomalies where SDS weather occurred either in a raised or reduced number during the period 1980-2006.…”

Process Optimization of Reaction Nitrogen Arc Welding Cladding TiCN/Fe Metal Ceramic Composite Coating

“…With excellent wear resistance, corrosion resistant, thermostability, the TiCN ceramic composite material has been used to improve surface properties of the cutting tool and machine parts widely. The main preparation technology of TiCN coating such as plasma chemical vapor deposition (PCVD) [1], plasma spraying (PS) [2] and reactive electric spark deposition (RESD) [3][4][5] and so on, have some drawbacks in some degree, such as process complex, high cost and thickness thin. Reaction nitrogen arc welding cladding can be used to process TiCN coating with tungsten electrode as a cathode, metal substrate precoated graphite powder and titanium powder as an anode, and high purity nitrogen as protection and response gas [6].…”