长江三角洲背景地区CO2浓度变化特征研究

通过分析2009年1月~2010年12月临安区域大气本底站在线观测获得的CO2浓度,研究地面风向、地面风速、气团输送等因素对长江三角洲背景地区CO2浓度的影响.结果表明,临安站CO2浓度的日变化分布表现为单峰型形态,下午低、凌晨高,浓度日变幅在9.5′10-6~44.3′10-6 (V/V)之间;季节变化特征表现为冬春季高,夏季低,浓度年较差为10.1′10-6 (V/V).通过分析地面风向、地面风速和气团输送等因素对临安站CO2浓度的影响表明,引起CO2浓度升高的地面风向夏季主要为NW~NNE,冬季主要为NNE~ESE;地面风速越大,CO2浓度越小;气团远距离输送的影响主要取决于气团途径区域的CO2排放情况.

Study on the concentration variation of CO2 in the background area of Yangtze River Delta

Atmospheric CO2 concentration was continuously measured from January 2009 to December 2010 to study the effects of surface wind direction,surface wind speed and air mass transport on CO2 concentration at Lin’an regional atmospheric background station.The results revealed that the diurnal variation of atmospheric CO2 concentration showed the single-peak pattern at Lin’an regional background station.The diurnal concentration of CO2 varied from 9.5×10-6(V/V) to 44.3×10-6(V/V),with the lowest value observed in the afternoon and the highest at dawn.The difference between maximum and minimum monthly mean CO2 concentrations was 10.1×10-6(V/V),with the highest concentration observed in winter and spring and the lowest in summer.Study on the effects of surface wind direction,surface wind speed and air mass transport on CO2 concentration showed the dominant wind directions were NW～NNE in summer and NNE～ESE in winter,which could bring on higher CO2 concentration.The CO2 concentration turned lower with higher surface wind speed.The impact of long-range transport of air masses on CO2 concentration depended on the source strength of CO2 in the pathway.