Wind-blown Sand Activity Intensity in Cuonahu Lake Section of Qinghai-Tibet Railway
Sand drift potential (DP) and sand transport amount are two important indices to reflect windblown sand activity intensity. The recorded wind data in Cuonahu Lake section of Qinghai-Tibet Railway from July 2009 to June 2010 are used to analyze the characteristics of sand-moving wind and to calculate DP. Results reveal that the change of sand-moving wind is obvious in different months, and west wind is the main wind direction from October to April of the following year, which accounts for more than 65% of the sand-moving wind frequency. From October to April of the following year, DP is high and the resultant drift direction (RDD) is west wind, and the direction variability rate is above 0. 9. From May to September, DP is low and wind directions are scattered, and the direction variability rate drops from 0. 61 in May to 0. 36 in September. The yearly drift potential in Cuonahu Lake is 491. 12 VU, so it has high wind energy (≥400 VU). The resultant drift potential is 445. 44 VU and the yearly direction variability rate (RDP/DP) is 0. 91 with RDD of 262. 54°. The monthly sand transport amounts range from 10. 5 kg in July to 119. 7 kg in November. The monthly sand transport amount increases with DP and mean wind velocity, and there is a power function relationship between monthly sand transport amount and monthly drift potential, and there is a linear relationship between monthly sand transport amount and mean monthly wind velocity.
sand-moving wind regimesand drift potentialsand transport amountthe Qinghai-Tibetan PlateauCuonahu Lake