卫星遥感监测海南地区对流层CO2浓度时空变化特征

为了探索海南地区对流层CO₂浓度以φ(CO₂)计]时空变化特征，采用2002年9月—2012年2月AIRS反演的对流层中层CO₂产品，利用北半球全球本底站瓦里关站和飞机观测φ(CO₂)对该产品进行验证，结合统计分析方法对海南地区φ(CO₂)的月、季、年平均值的时空变化特征进行了研究.结果表明:AIRS反演φ(CO₂)与地基和不同纬度带海洋上空飞机观测数据对比均具有很好的一致性，并且与飞机观测验证偏差更小，二者相关系数均在0.9以上，总体月均值偏差小于2×10-6；全国φ(CO₂)呈现北高南低的分布规律，并且存在较为明显的分界线，形成4个高值中心(塔克拉玛干沙漠、塔里木盆地、内蒙古西部和东北平原)和2个低值中心(青藏高原西南部和云南地区)，海南地区平均φ(CO₂)为382.67×10-6，略高于云南低值中心的381.45×10-6；全国φ(CO₂)呈现明显逐年增加趋势，其年均增长速率为2.16×10-6，而海南地区亦呈现显著增加趋势，年均增长速率为2.11×10-6，低于全国水平；φ(CO₂)呈季节性波动特性，全国φ(CO₂)最高值出现在春季，而海南地区为夏季，最低值均出现在秋季；海南地区西部海域、陆地和东部海域上空φ(CO₂)年增长速率分别为2.09×10-6、2.14×10-6和2.11×10-6，表明海南陆地上空增速略大于海洋地区，西部和东部海域上空增长速率基本保持一致. 

Satellite Remote Sensing for Monitoring Spatial-Temporal Variations of Tropospheric CO2 over Hainan

The atmospheric infrared sounder (AIRS) mid-tropospheric CO₂ products from September 2002 to February 2012 were used to study the spatial-temporal variations of tropospheric CO₂ over Hainan. The products were separately validated with observations from a global ground-based station, Waliguan, and aircraft in the Northern Hemisphere. The results indicated that AIRS CO₂ products showed a high consistency with Waliguan and aircraft observations, especially for the aircraft. Both correlation coefficients were above 0.9, with monthly average deviations below 2×10-6. Mid-troposphere CO₂ concentrations over northern China were higher than over the southern areas with a distinct boundary. There were four centers with high CO₂ concentrations in Tarim Basin, Taklimakan Desert, western Inner Mongolia and Northeast China Plain. Two centers with low CO₂ concentrations were in southwestern Qinghai-Tibet Plateau and Yunnan Province. Hainan Province, with CO₂ concentration at 382.67×10-6, was slightly higher than Yunnan Province (381.45×10-6). The CO₂ concentrations increased from 2002 to 2012 over China; the annual average growth rate was 2.16×10-6 in mainland, with maximum value in spring and minimum value in autumn. CO₂ concentrations also increased over Hainan; Hainan was 2.11×10-6, with the maximum value in summer and minimum value in autumn. The annual growth rates over the western sea, land and eastern sea areas of Hainan were 2.09×10-6, 2.14×10-6 and 2.11×10-6, respectively. This result indicated that the growth rate in land area was slightly higher than sea areas in Hainan Province, and the sea areas were almost consistent.