Impacts of El Niño-Southern Oscillation on surface dust levels across the world during 1982-2019

Impacts of February climate conditions in the Gobi Desert on March dust activities in the northern East Asia

Amid ongoing global warming, intense dust storms continue to plague regions despite efforts to understand and mitigate their impacts. This study explores the connection between surface temperature (ST) and precipitation (PRE) in the Gobi Desert (GD) during February and their subsequent effects on March dust concentrations across northern East Asia. Our analysis reveals a clear pattern: higher February ST combined with lower PRE in GD correlates with increased dust levels in March, with ST effects predominantly in northern areas of dust sources compared to PRE. The warming of the ST in February facilitates surface thawing, and the concurrently reduced PRE decreases soil moisture in GD. These conditions both contribute to the loosening of the soil, thereby creating favorable lower boundary conditions for the onset of dust activities in the subsequent March. Atmospheric dynamics play a pivotal role in the changes of ST and PRE. The preceding ST warming is closely tied to the weakening of the East Asian winter monsoon. Furthermore, the Eurasia teleconnection (EU) pattern is identified as a key circulation factor driving the changes of February PRE in GD. Additionally, sea surface temperature anomalies in the Barents Sea and the North Atlantic appear to influence these atmospheric circulation changes, altering ST and PRE in GD, and consequently, impacting March dust dynamics in northern East Asia. This study provides crucial insights into the climatic precursors that drive dust storm activities, which are essential for improving the accuracy of dust storm forecasting.

Dynamic Variability of Wind Erosion Climatic Erosivity and Their Relationships with Large-Scale Atmospheric Circulation in Xinjiang, China

Xinjiang has a serious wind erosion problem due to its fragile ecological condition and sensitivity to climate change. Wind erosion climatic erosivity is a measure of climatic factors influencing wind erosion; evaluating its spatiotemporal variations and relationship with the large-scale circulation pattern can contribute to the understanding of the climate change effect on wind erosion risk. Thus, this study quantified the wind erosion climatic erosivity and examined the connections between climatic erosivity and climate indices using trend analysis, geo-statistical analysis, and cross-wavelet analysis based on the observed daily meteorological data from 64 weather stations in Xinjiang, China during 1969–2019 (50 years). The results indicated that the climatic erosivity showed a significant downward trend at seasonal and annual scales over the past 50 years. Strong seasonality in the C-factor was found, with its highest values in the spring and summer and its lowest values in the winter. The average climatic erosivity was weaker during El Niño events than during La Niña events. The impact of El Niño events on climatic erosivity in Xinjiang continued from the beginning of the event to two months after the end of the events. The La Niña events had a lag effect on the climatic erosivity in Xinjiang, with a lag period of 4 months. From a statistical perspective, the El Niño-Southern Oscillation (ENSO), North Atlantic Oscillation (NAO), and Arctic Oscillation (AO) indices showed relationships to the climatic erosivity in Xinjiang in terms of their correlation and periodicity. The relationships between the climatic erosivity and ENSO were not clearly positive or negative, with many correlations advanced or delayed in phase. The NAO and AO indices showed a consistent in-phase relationship with climatic erosivity on significant bands, whereas the profound mechanisms involved in this require further study. The results of this study provide a preliminary perspective on the effect of large-scale atmospheric circulation on wind erosion risk in arid and semi-arid regions.