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Six dust storms that originated from Mongolia and moved to northern China in Spring 2021 are investigated by the anomaly variable‐based analysis method, which is compared to the traditional total‐variable based analysis method. Strong surface wind is a force to form dust storms as commonly known in current practice. However, dust area depicted by total‐wind model product analysis and operational forecast has a large bias to observation even for leading 24 hr. The analysis method of anomaly based variables showed that the domain of an airborne dust storm observed from satellite images is usually located between two neighboring convergence lines of 850 hPa anomalous winds. This connection of dust storm associated with the anomalous wind convergence extends southwestward from an anomalous cyclone and moves from Mongolia to northern China or Northeast China. It is thermodynamically associated with an anomalous thermal contrast, which has a spatial structure of wind, temperature, and geopotential height anomalies in the troposphere. We further found that numerical weather prediction products of the ECMWF model are able to indicate the anomalous wind pattern with lead times of 4–8 days by applying the anomaly based analysis approach. Therefore, this approach can not only depict dust area better but also reveal predictors much easier compared to the traditional total‐variable or full‐field‐based analysis method. Key Points: Dust storm can be well detected by the anomaly based analysis of atmospheric variablesA dust domain is located between two neighboring convergence lines of 850 hPa anomalous windsThe ECMWF model can predict the anomalous wind pattern for leading 4–8 days [ABSTRACT FROM AUTHOR]

It is well‐known that the increasing zonal‐mean trend of sea‐ice concentration (SIC) surrounding Antarctica is up to 2015 so this paper first summarized this trend with opposing regional trends in each season along the latitude band 60°–70°S during 1979–2015. The surface wind trends can partly explain the observed regional SIC trends. By analysing the surface wind, as well as the tropospheric geopotential height (GPH) and temperature trends, the study revealed that the increasing zonal‐mean SIC trend and opposing regional SIC trends surrounding Antarctica are vertically associated with GPH and temperature trends in the troposphere. This relationship is also found in extreme years for seven SIC maximum and four SIC minimum autumns from 1979 to 2015, particularly reconfirmed in the two SIC minimum autumns of 2017 and 2018, indicating that a positive regional SIC anomaly is vertically associated with an anomalously cold air mass centred around 850 hPa in the troposphere which is located beneath a negative GPH anomaly at the upper troposphere, and vice versa. [ABSTRACT FROM AUTHOR]

ABSTRACT In the summer of 2010, western Russia experienced extreme heat, which was noted for its exceptional spatial spread, long duration, high intensity and impacts. We use an anomaly-based approach to decompose atmospheric variables into daily climatic components and anomalies from two reanalysis datasets. We show that a surface heat wave event results from a downward extension of an anomalously warm air column below a centre of positive geopotential height anomalies in the upper troposphere. Therefore, we use this approach to analyse all summer regional heat wave events with spatial scales larger than 2000 km and durations greater than 5 days over western Eurasia from 1980 to 2014. Our results demonstrate that the rapid increase in regional heat wave events over western Eurasia since 2010 is a direct response to the increasing frequency of large-scale, quasi-stationary positive centres of maximum height anomalies in the upper troposphere. [ABSTRACT FROM AUTHOR]