By combining observations from three meteor radars and a mesosphere‐stratosphere‐troposphere radar arranged along the 120°E meridian with reanalysis data from 20 February to 20 May 2015, we study the stratospheric final warming (SFW) in 2015 spring and planetary wave activities from the troposphere to the mesosphere and lower thermosphere (MLT) at different latitudes. There are two successive warming events with the polar mean temperature rises of 24 and 9 K at 10‐hPa level. By means of the two warming events separated by only several days, the mean temperature increases by nearly 20 K, and the mean zonal wind decreases from more than 30 m/s to about −10 m/s; thus, seasonal transition of the polar circulation is completed. The investigation shows that the quasi 10‐ (Q10DW) and 16− (Q16DW)day waves occur around the SFW. In the troposphere, their amplitudes are close to 10 m/s in the wind field. At 10‐hPa level of the stratosphere, the strong wave activities arise before the SFW, while in the MLT, the waves are amplified following the SFW with the amplitude peaks about 10 days after the SFW onset. The wave amplitude in the MLT tends to increase in the zonal wind but decrease in the meridional wind with decreasing latitude, which is roughly consistent with the Hough modes. Hence, the Q10DW and Q16DW in the MLT are distinct from those in the stratosphere, and they are likely to be generated and strengthened in situ in the upper stratosphere and MLT.

Purpose – This paper aims to solve the disadvantages of content-based domain ontology (CBDO) and metadata-based domain ontology (MDO) and improve organization and discovery efficiency of library resources by resource ontology (RO). Design/methodology/approach – The paper constructed an RO model. Methods of informetrics are utilized to reveal semantic relationships among library resources. Methods of ontology, ontology-relational database mapping (O-R mapping) and relational database modelling are utilized to construct RO. Take author co-occurrence for example, the paper demonstrated the capability of RO model. Findings – RO not only revealed the deep-level semantic relationships of metadata of library resources but also realized totally computer-automated processing. RO improved the efficiency of knowledge organization and discovery. Research limitations/implications – Semantic relationships revealed by RO are limited to simple metadata, which makes it difficult to reveal fine-grained semantic relationships. Ongoing research focuses on the revelation of semantic relationships based on the title and abstract. Practical implications – The paper includes implications for utilizing methods of Informetrics to construct ontology. Originality/value – This paper proposed a standardized process of ontology construction in library resources. It may be of potential interest for anyone who needs to effectively organize library resources.

There are few reports on quasi 6‐day wave (Q6DW) during stratospheric sudden warming (SSW) events, especially the eastward propagating one. By using observations from three meteor radars and three radiosondes combined with reanalysis data from January to March 2016, we study the eastward propagating Q6DWs during the SSWs from the troposphere to the mesosphere and lower thermosphere (MLT). There are SSW and stratospheric final warming (SFW) events around February and March in the northern hemisphere, respectively. The polar mean temperature rises by about 45 and 36 K at 10‐hPa level and the mean zonal wind decreases by about 38 and 49 ms−1 during the SSW and SFW, respectively. Large‐scale zonal wind reversal happens during the SSWs. Radar observations and reanalysis data show that two Q6DWs corresponding to the SSWs are robust from the troposphere to the MLT. They are eastward traveling waves with zonal wavenumbers 1–2. The Q6DWs propagate downward in the stratosphere and upward in the MLT, implying that the source of the Q6DWs is in the mesosphere. The meridional gradient of quasi‐geostrophic potential vorticity and Eliassen‐Palm flux divergence show that the instabilities possibly occur in the mesosphere, which likely in situ excite and strengthen the Q6DWs. The instabilities are also found in the stratosphere and may amplify the Q6DWs in the stratosphere at the three stations especially during the SSW.