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The South-East Asian boundary layer has witnessed alarming pollution levels in recent years, which even affects the trace gas composition in the southern hemisphere by inter-hemispheric transport. We use SF6 observations and the Lagrangian chemistry transport model CLaMS, driven by the ERA5 reanalysis data for the period 2010–2014, to assess the impact of the Asian monsoon (AM) region [15° N, 45° N, 30° E, 120° E] as a significant source of pollutants for the stratosphere, in particular in polar regions. We examine the contribution of transport from the AM region to the Northern Hemisphere polar region (NP) [60° N, 90° N] and to the Southern Hemisphere polar region (SP) [60° S, 90° S]. Despite the smaller geographical size of the AM region when compared to the Southern Hemisphere subtropics [15° S, 45° S] and tropics [15° S, 15° N], our findings reveal that the air mass fractions from the AM to the polar regions are approximately 1.5 times larger than the corresponding contributions from the Southern Hemisphere subtropics and roughly two times smaller than those from the tropics. The transport of air masses from the AM boundary layer to the stratospheric polar vortex primarily occurs above an altitude of about 450 K and over timescales exceeding 2 years. In contrast, transport timescales to the polar regions situated below the vortex are shorter, typically less than about 2 years. Furthermore, the transport contribution from the AM region to the polar regions exhibits distinctive inter-annual variability, significantly influencing the distributions of pollutants. Our analysis of detrended SF6 from ACE-FTS over the polar regions reveals a strong correlation with the fraction of relatively young air (less than two years old) originating from the AM, Southern Hemisphere subtropics, and tropics. Importantly, our reconstructed SF6 data indicates that approximately 20 % of SF6 in both the northern and southern polar stratosphere originates from the AM boundary layer. The largest fraction of SF6 in the polar stratosphere still originates from the tropical boundary layer, contributing about 50 % of SF6. [ABSTRACT FROM AUTHOR]

Enhancing the understanding and management of ecosystem services (ESs) supply and demand under the influence of global change is crucial for sustaining human well‐being and promoting sustainable development. However, the comprehension of changes in ecosystem service dynamics in the face of complex human disturbances remains limited. This study focuses on four representative ESs in the northern Liaodong Bay, a typical global estuary wetland, to elucidate alterations in the supply and demand of these ESs and comprehend the impact mechanisms arising from reclamation activities. The findings reveal the following key insights: between 1993 and 2020, the supply and demand for water yield disparity became increasingly pronounced, while the equilibrium between supply and demand for carbon storage shifted from surplus to balance. In contrast, the excess supply–demand of food supply and landscape esthetics remained relatively consistent. This study delves deeper into the non‐linear relationship between reclamation activities and ESs supply–demand relationships, with each ecosystem service exhibiting distinct patterns. As reclamation intensity rises, the supply–demand ratio of ESs exhibits varying trends: food supply and carbon storage demonstrate an inverted U‐shaped relationship, water yield follows a U‐shaped pattern, and landscape esthetics progressively decline. By identifying reclamation thresholds, different management strategies should be applied to areas exceeding and falling below these thresholds, with constraints and guidance being necessary for the former and the latter, respectively. These findings advance our understanding of ESs dynamics in the context of human‐driven changes and provide practical implications for sustainable ecosystem management in coastal areas. [ABSTRACT FROM AUTHOR]

Les trois caractères chinois: Shēng, Yīn et Yuè sont omniprésents dans les textes classiques chinois concernant la musique. En général, on pense que Shēng est une imitation du son naturel, et Yīn est le positionnement du son selon certaines règles. Pourvu de sens sociaux et rituels, Yuè représente souvent l’ensemble de la musique instrumentale, le chant et la danse. Toutefois, ces trois caractères reçoivent des sens très divers selon les contextes. Dans cet article, nous essayons d’analyser et discerner le sens des trois caractères chinois dans des textes classiques datant de l’époque pré-impériale, des textes significatifs de la pensée de la Chine antique ainsi que des évolutions de la technique musicale.