Extreme precipitation (EP) has significant hydrological and environmental influences on the Chinese Loess Plateau (CLP) during the rainy season (June–September). In this study, we analysed the moisture sources for the EP events over the CLP during the rainy season. Three major moisture source patterns were identified through analysing the moisture source variability across the EP events with a newly developed method combining the Lagrangian moisture diagnostic and a clustering algorithm. South China and North China were determined as the most critical moisture source regions for the EP events over the CLP. The three moisture source patterns corresponded to three EP types, including the CLP‐A type with a high contribution from North China (23.55%, the relative moisture contribution) and a relatively low contribution from South China (13.77%), and the CLP‐B and CLP‐C types, which had limited contributions (10.64% and 13.28%) from North China in common, and exhibited moderately high (19.30%) and extremely high (30.59%) contributions from South China, respectively. The moisture transport pathways for the three EP types were quantitatively analysed in detail. The favourable circulation patterns for the three EP types were further illustrated to reveal the atmospheric conditions for the spatial variations in moisture source patterns. In addition, this study provides a new strategy to analyse the moisture source variability, especially when it is difficult to find an easily manipulated criterion to classify the precipitation events.

Anomalous poleward transport of atmospheric energy can lead to sea ice loss during boreal winter over the Arctic, especially in the North Barents–Kara Seas (NBKS), by strengthening downward longwave radiation (DLW). However, compared with the extensive studies of latent energy sources, those of sensible energy sources are currently insufficient. Therefore, we focus on the intraseasonal sea ice loss events from the perspectives of both energy forms. First, the contributions of latent and sensible energy to DLW and sea ice reduction are quantified using the lagged composite method, a multiple linear regression model, and an ice toy model. Second, a Lagrangian approach is performed to examine sources of latent and sensible energy. Third, possible underlying mechanisms are proposed. We find that the positive anomalies of latent and sensible energy account for approximately 56% and 28% of the increase in DLW, respectively, and the DLW anomalies can theoretically explain a maximum of 58% of sea ice reduction. Geographically, the North Atlantic, Norwegian–North–Baltic Seas, western Europe, and northeastern Pacific are major atmospheric energy source regions. Additionally, while the contributions of latent energy sources decrease with increasing distance from the NBKS, those of sensible energy sources are concentrated in the midlatitudes. Mechanistically, latent energy can influence sea ice decline, both directly by increasing the Arctic precipitable water and indirectly by warming the Arctic atmosphere through a remote conversion into sensible energy. Our results indicate that the Rossby waves induced by latent heating over the western tropical Pacific contribute to anomalous energy sources at midlatitude Pacific and Atlantic both dynamically and thermodynamically.

Temperature extremes have been related to anomalies in large-scale circulation, but how these alter the surface energy balance is less clear. Here, we attributed high extremes in daytime and nighttime temperatures of the eastern Tibetan Plateau to anomalies in the surface energy balance. We find that daytime high-temperature extremes are mainly caused by altered solar radiation, while nighttime ones are controlled by changes in downwelling longwave radiation. These radiation changes are largely controlled by cloud variations, which are further associated with certain large-scale circulations that modulate vertical air motion and horizontal cloud convergence. In addition, driven by a high-pressure system, strengthened downward solar radiation tends to decrease the snow albedo, which then plays an important role in reducing upward solar radiation, especially during winter and for compounding warm events. The results during winter and summer are generally similar but also present significant differences in terms of the contribution of variations in snow albedo, surface turbulent fluxes, and horizontal advection of cloud, which hence need further attention in simulating the high-temperature extreme events in the eastern Tibetan Plateau. Our work indicates the importance to attribute different temperature extremes separately from the perspective of energy balance.

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