Spring sand-dust weather distribution in Hunshandak Sandy Land in relation to vegetation and wind in 2000-2023
By using long-time series remote sensing observations,surface meteorological observations,and air quality monitoring data,the underlying surface improvement of Hunshandak Sandy Land and the characteristics of spring sand-dust weather since the implementation of the Beijing-Tianjin Sand Source Control Program were analyzed.The results showed that compared with the years 2000 to 2009,the vegetation coverage significantly increased in over 22%of the Hunshandak Sandy Land from 2010 to 2022.The sand-dust weather in the Hunshan-dak Sandy Land mainly occurred under the influence of westerly winds,showing a trend of first decreasing and then increasing..The period from 2000 to 2006 was a period of frequent occurrence of sand-dust weather.From 2007 to 2014,the number of sand-dust days decreased,and the number of sand-dust days increased again from 2015 to 2023.The trend of the sand-dust days was consistent with the trend of strong winds above level 6.The de-crease in the number of strong winds combined with the decrease in the frequency of sand formation had led to a significant decrease in the proportion of sand formation times under the influence of strong winds above level 6,from nearly 80%at the beginning of this century to around 30%-40%in recent years.As a result,the sand-dust weather under lower wind speeds had seen a significant increase.From 2012 to 2023,the impact of sand-dust weather from overseas was becoming increasingly significant in the Hunshandak Sandy Land.Compared to local sand-dust weather,the impact range of sand-dust weather from overseas was larger.
Hunshandak Sandy Landvegetation coveragesand formationtemporal and spatial distribution characteristicsregional sand-dust weather