In this paper, concurrent/colocated measurements of seismometers, infrasonic systems, magnetometers, HF‐CW (high frequency‐continuous wave) Doppler sounding systems, and GPS receivers are employed to detect disturbances triggered by seismic waves of the 11 March 2011 M9.0 Tohoku earthquake. No time delay between colocated infrasonic (i.e., super long acoustic) waves and seismic waves indicates that the triggered acoustic and/or gravity waves in the atmosphere (or seismo‐traveling atmospheric disturbances, STADs) near the Earth's surface can be immediately activated by vertical ground motions. The circle method is used to find the origin and compute the observed horizontal traveling speed of the triggered infrasonic waves. The speed of about 3.3 km/s computed from the arrival time versus the epicentral distance suggests that the infrasonic waves (i.e., STADs) are mainly induced by the Rayleigh waves. The agreements in the travel time at various heights between the observation and theoretical calculation suggest that the STADs triggered by the vertical motion of ground surface caused by the Tohoku earthquake traveled vertically from the ground to the ionosphere with speed of the sound in the atmosphere over Taiwan.

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Aircraft and airborne cloud radar data are used to describe the vertical structure of the convective boundary layer (CBL) during cold-air outbreaks over Lake Michigan in January 2004. Two days with mesoscale cloud street structure and a day with cellular organization are contrasted. The radar reflectivity and vertical velocity structure of the CBL, as well as the radar-inferred topography of the CBL inversion, are collected along flight legs normal to the cloud streets. High-resolution horizontal and vertical transects of the dual-Doppler airflow field capture horizontal convective roll circulations on one day. Coherent structures within the CBL are analyzed as echo plumes, updraft plumes, and CBL domes. Only updraft plumes have the characteristics of buoyant thermals. Updrafts are narrower, weaker, and less buoyant on the no-roll day, but the differences in characteristics between two cloud street days are larger than those between the no-roll day and the two cloud street days. The lack of a clear buoyancy signal in echo plumes and under CBL domes is attributed to a temporal phase shift between maximum buoyancy, maximum ice particle size, and maximum overshooting in thermals, and the transience of convective updrafts.

Green product certification (GPC) is an important means of eliminating the asymmetry of information between consumers and manufacturers in the context of sustainable development. This study examined the critical risk factors in GPC and provided relevant suggestions for managers to reduce risk and ensure the correctness of the process. First, 18 risk factors were summarized along four dimensions: the certification institution, the entrusting enterprise, the certification business, and the implementation of the certification. Second, the Delphi method was used to determine the formal research framework, and the decision-making trial and evaluation laboratory (DEMATEL) method was applied to analyze the causal relationships among the risk factors to identify the ones driving risk and those representing the outcomes of GPC. This was used to construct a causality diagram of the risks related to green certification. Finally, the analytic network process (ANP) method was used to calculate the weight of each risk factor, and the weighted prominence of each is calculated to identify the critical factors. The results showed that the working life and experience of the certification institution were the critical driving risk factors in GPC. Corresponding countermeasures were also proposed to mitigate these risk factors.