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Dust–cloud–surface radiation interactions are a complex nonlinear relation referring to the influences of both atmospheric dust and dust-on-snow on surface albedo. A ‘Tiramisu’ snow event occurred on 1 December 2018, in Urumqi, China, providing an excellent testbed for exploring the comprehensive effect induced by atmospheric dust and those deposited atop fresh snowpack on surface radiation. A detailed analysis indicates that the decrease of snow albedo by 0.17–0.26 (22%–34%) is contributed by the effects both the dust–cloud interactions and dust-on-snow at synoptic scale in this case. In particular, dust well mixed with ice clouds at altitudes of 2.5–5.5 km disrupted the ‘seeder–feeder’ structure of clouds and heterogeneous ice nucleation. Dust-induced changes in the low layer of ice clouds (3.3–5.5 km) under a low temperature of –20 °C resulted in a 31.8% increase in the ice particle radius and 84.6% increase in the ice water path, which acted to indirectly buffer the incident solar radiation reaching the surface. Dust particles deposited on the snow surface further caused snow darkening since the snow albedo was found to decrease by 11.8%–23.3%. These findings underscore the importance of considering the comprehensive effect of dust–cloud–radiation interactions in the future.

While there is considerable agreement in the scientific community about the intensification of tropical cyclones (TCs) in a warming world, that consensus does not exist for TC frequency. In order to shed new light on this uncertainty, we classified the global oceans into three pools based on SST percentiles: the (a) warm (≥90th percentiles), (a) moderate (65th–90th percentiles) and (c) cool (

The El Niño-Southern Oscillation (ENSO) pendulum swings back and forth between the El Niño and La Niña phenomena. To monitor the relative phase changes of the ENSO pendulum, 13 clusters are obtained based on the pattern of sea surface temperature anomalies (SSTAs) along the equatorial Pacific. The historical ENSO evolution can be effectively described by the alternation among those clusters. The zonal movement of SSTA loading during the ENSO evolution can also be captured by the changes in the clusters. One scheme was designed to monitor the ENSO pendulum based on those clusters as well the SSTAs in the Niño-3.4 region. When applied in practice to monitor historical ENSO events, including the 1997 El Niño and 2015 El Niño phenomena, the scheme tends be suitable for describing the ENSO pendulum between El Niño and La Niña, and it has the advantage of presenting both the ENSO amplitude and SSTA pattern.

In this paper, we analyze observational and reanalysis data to demonstrate that the Atlantic Multidecadal Oscillation (AMO) significantly modulates winter Eurasian surface air temperature through its impact on the shape, frequency and persistence of Ural blocking (UB) events that last for 10–20 d. This impact results from changes in mid-high latitude westerly winds over Eurasia associated with the warming in the Barents–Kara Seas (BKS) through the AMO-driven high sea surface temperature and sea-ice decline and resultant weakening in meridional temperature gradients. The BKS warming has a strongest positive correlation with the AMO at a time lag of about 14 years. During the recent positive AMO phase, more persistent northwest–southeast (NW–SE) oriented UB events are favored by weakened westerly winds in Eurasian mid-high latitudes. Through cold atmospheric advection and radiative cooling, such UB events produce a strong, persistent and widespread cooling over Eurasia and enhance BKS warming during 1999–2015. However, the positive AMO phase cannot directly produce the Eurasian cooling if the UB is absent. Thus, we conclude that the recent AMO phase change is a major cause of the recent winter cooling over Eurasia through its impact on BKS temperature and sea ice, which in turn affect the meridional temperature gradient, the westerly winds and the UB events.