During the Transport and Chemical Evolution Over the Pacific (TRACE‐P) period in the spring of 2001 we launched an ozonesonde at three Chinese sites: Kunming (102.68°E, 25.03°N), Hong Kong (114.17°E, 22.31°N), and Linan (119.75°E, 30.30°N). The sites extend from subtropical southwestern China close to the Southeast (SE) Asian border, to the southeastern Asian coast, and to the edge of the middle latitudes of central eastern China, respectively. The aims of the study are to provide ozonesonde data within the source regions of the Chinese mainland, to investigate the source of tropospheric ozone (O3), and to investigate to what extent SE Asian biomass burning emissions impact both tropospheric O3 over the subtropical Chinese mainland and O3 outflows to the Pacific. The results show that there are substantial variations in vertical O3 distributions over these sites, with low O3 values in the upper troposphere of Hong Kong, high O3 values in the middle and upper troposphere of Linan, and frequent O3 enhancements in the lower troposphere of Hong Kong and Kunming. The low values in the upper troposphere over Hong Kong in the spring of 2001 were not usually observed from 1993 to 2000 and are the result of the transport of O3‐depleted air from the intertropical convergence zone of equatorial SE Asian regions following the eastern Asia local Hadley circulation. Such transport processes do not affect the higher latitude at the edge of the middle latitude of Linan, where stratospheric O3 is the major contributing source to middle and upper tropospheric O3. The O3 enhancements over the lower troposphere of Kunming and Hong Kong are caused by SE Asian biomass burning emissions. Such enhancements are frequently observed over Hong Kong, less often over Kunming, and scarcely ever over Linan. Our analysis shows that biomass burning emissions from SE Asia in the spring of 2001 mainly affected the southern parts of the subtropical Chinese region.

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During the Pacific Exploration of Asian Continental Emission (PEACE) phase A mission in January 2002, we launched ozonesondes in subtropical southeast China at Hong Kong (114.17°E, 22.31°N), middle latitude northeast China at Beijing (116.47°E, 39.81°N), and northwest China at Xining (101.45°E, 36.43°N) in order to study long‐range ozone (O3) transport from Eurasia, tropospheric O3 sources in China, and O3 outflow to the Pacific. Tropospheric O3 showed a complex vertical distribution with average tropospheric O3 columns of 39 ± 4, 23 ± 3, and 30 ± 6 DU in Hong Kong, Beijing, and Xining, respectively, which accounted for 17 ± 2%, 7 ± 1%, and 10 ± 1% of the total O3 column. The lower tropospheric and boundary layer (BL) O3 over Xining and especially Beijing exhibited low values, suggesting negligible O3 formation in middle latitudes of China during the winter season. The results also revealed frequent propagation of enhanced O3 layers from the lower stratosphere to the upper troposphere over Xining and especially Beijing, suggesting that stratospheric O3 is an important source of O3 in the upper troposphere of northern China. This “natural” O3 is transported downwind by the prevailing westerly wind and acts as a source of O3 to the east Asian coast and northwestern Pacific. We observed elevated O3, with a maximum mixing ratio up to 111 ppbv, at 1.5 km in the upper BL over Hong Kong. The elevated O3 was resulted from transport of pollutants from northwest‐central or southwest China and regional O3 formation and accumulation in south China including the Pearl River Delta and Hong Kong. We also observed enhanced O3 (>95 ppbv) in the middle and upper troposphere over Hong Kong in air masses transported along the subtropical jet from tropical and subtropical East Africa, south Asia, and Southeast Asia. The O3 enhancements were most likely due to intrusion of stratospheric O3 into the troposphere in the Indo‐Burmese region of tropical Southeast Asia, where substantial downward motion had been observed.

Featuring excellent coherence and operated parallelly, ultracold atoms in optical lattices form a competitive candidate for quantum computation. For this, a massive number of parallel entangled atom pairs have been realized in superlattices. However, the more formidable challenge is to scale-up and detect multipartite entanglement due to the lack of manipulations over local atomic spins in retro-reflected bichromatic superlattices. Here we developed a new architecture based on a cross-angle spin-dependent superlattice for implementing layers of quantum gates over moderatelyseparated atoms incorporated with a quantum gas microscope for single-atom manipulation. We created and verified functional building blocks for scalable multipartite entanglement by connecting Bell pairs to one-dimensional 10-atom chains and two-dimensional plaquettes of 2 × 4 atoms. This offers a new platform towards scalable quantum computation and simulation.

Tropospheric ozone (O 3 ) profiles over the east China coast at LinAn (30.30 • N, 119.75 • E) were measured by electrochemical concentration cell ozonesondes in the spring of 2001. The measurement revealed that extremely high O 3 with mixing ratios up to 1200 ppbv sometimes penetrated deeply into 8.5-16 km above sea level as a result of lowering of the tropopause across the East Asia strong subtropical jet stream. In addition, high O 3 in the 75-150 ppbv range penetrated into the upper and middle troposphere following the extreme O 3 regimes and caused an overall high O 3 mixing ratio in these regions. The occurrence of the high O 3 regimes followed the propagation of dry air with low relative humidity and high potential vorticity suggesting that the O 3 is of stratospheric origin. High O 3 episodes with O 3 mixing ratios in the 75-100 ppbv range were observed in the lower troposphere and especially in the boundary layer. Trajectory analysis suggested that the O 3 -rich air masses had passed through the industrialized and urbanized zones of the Pearl River Delta region of south China, northeast China coast and Yangtze River Delta region of east China. The O 3 is probably of anthropogenic origin resulting from photochemical formation from pollutants emitted from these regions. Our analysis thus revealed that over the east China coast at LinAn, stratospheric O 3 is still the predominant source of O 3 in the middle and upper troposphere, while anthropogenic sources caused a high O 3 pollution episode in the boundary layer.