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输沙势和输沙量是反映风沙活动强度的两个重要指标。利用青藏高原错那湖2009年7月—2010年6月的风速资料,统计并计算起沙风频次和输沙势。分析结果表明,起沙风的月际变化比较明显,10月至翌年4月风向单一,以西风为主,约占全年起沙风的65%以上。从10月到翌年4月输沙势值较高,合成输沙方向以西风为主,方向变率指数在0.9以上,属于高比率。5月到9月输沙势值处于年内低峰,风向比较分散,方向变率指数由5月的0.61降到9月的0.36,属于中比率。年输沙势为491.12VU,属于高能环境(≥400VU)。年合成输沙势为445.44VU,年方向变率为0.91,属于高比率,合成输沙方向为262.54°。对8个方位月输沙量分析显示,月输沙量变化在10.5kg(7月)～119.7kg(11月)之间,各月输沙量随输沙势和平均风速的增加而增加,其转化关系可以用近似幂函数和线性函数表达。
Sediment transport and sediment load are two important indicators of the intensity of sand blown. Based on the wind speed data of Lake Kerna in the Qinghai-Tibet Plateau from July 2009 to June 2010, the frequency of sand-blowing and the sand-transport potential were calculated and calculated. The analysis shows that the monthly variation of the sandstorm is obvious. The wind direction is single from October to April of the next year, with the westerly wind prevailing, accounting for more than 65% of the annual total. From October to April the following year, the value of sediment transport is high, and the direction of synthetic sediment transport is mainly westerly with the rate of change of direction of direction above 0.9, which is a high rate. During the period from May to September, the negative sediment transport value was at a low level during the year with a more dispersed wind direction. The directional variability index dropped from 0.61 in May to 0.36 in September, a medium rate. Annual sediment transport is 491.12VU, belonging to high-energy environment (≥400VU). The annual sediment transport potential was 445.44VU, and the annual rate of change was 0.91, belonging to a high ratio. The synthetic sediment transport direction was 262.54 °. The analysis of monthly sediment load in 8 directions shows that the monthly sediment load changes between 10.5kg (July) and 119.7kg (November), and the sediment load in each month increases with the increase of sediment load and average wind speed, The transformation relation can be expressed by approximate power function and linear function.