Air mass motion, temperature, and humidity over the Arabian Sea and western Indian Ocean during the INDOEX intensive phase, as obtained from a set of superpressure drifting balloons
Air mass motion, temperature, and humidity over the Arabian Sea and western Indian Ocean during the INDOEX intensive phase, as obtained from a set of superpressure drifting balloons
复制标题
从一组超压漂流气球获得的 INDOEX 密集阶段阿拉伯海和西印度洋上空的气团运动、温度和湿度
DOI：
10.1029/2001jd001120
复制
发表时间：
2002
影响因子：
--
通讯作者：
G. Viswanathan
中科院分区：
文献类型：
--
作者：
C. Ethe;C. Basdevant;R. Sadourny;K. Appu;L. Harenduprakash;P. Sarode;G. Viswanathan
[1] 在印度洋实验 (INDOEX) 强化现场阶段，从果阿发射了 17 个在对流层较低层漂流的超压气球，以采样源自印度次大陆的污染气团的运动和气象特征。正如预期的那样，质量流被吸引到热带辐合带（ITCZ），大约在 7 天后到达。连续的轨迹显示了流动状态变化的证据，与 Meteosat-5 图像一致并说明了马登-朱利安振荡。气球还显示了印度西海岸附近沿海反气旋环流的证据，这与高止山脉的地形和昼间沿海风中尺度风系统有关。这些中尺度环流对于人为或矿物污染物穿过海岸的输送可能很重要。气球上收集的气象数据与欧洲中期天气预报中心（ECMWF）每半小时在气球连续位置进行时间和空间插值分析进行系统比较。风速、温度和湿度方面的一致性总体良好。然而，在海洋边界层之上，气球数据似乎表明分析温度偏冷，水平风偏东北。所分析的风的变异性的低估可以部分地通过分析系统中的网格尺寸平滑来解释。
[1] During the Indian Ocean Experiment (INDOEX) Intensive Field Phase, 17 superpressure balloons drifting at lower tropospheric levels were launched from Goa to sample the motion and meteorological characteristics of polluted air masses originating from the Indian subcontinent. The mass flow, as expected, is attracted to the Intertropical Convergence Zone (ITCZ), which is reached in about 7 days. Successive trajectories show evidence of shifts in the flow regime, consistent with Meteosat-5 imagery and illustrative of the Madden–Julian oscillation. Balloons also show evidence of coastal anticyclonic circulations off the western coast of India, linked to both the orography of the Ghâts and the diurnal coastal wind mesoscale wind systems. These mesoscale circulations may be important in the transport of anthropogenic or mineral pollutants across the coast. The meteorological data gathered on board the balloons were systematically compared with European Centre for Medium-Range Weather Forecasts (ECMWF) analyses interpolated in time and space at the balloons' successive locations every half-hour. The agreement is generally good in terms of wind velocities, temperature, and humidity. However, above the marine boundary layer, balloon data seem to indicate a cold bias of analyzed temperatures and a northeasterly bias of horizontal winds. The underestimation of variability in the analyzed winds can be partly explained by mesh size smoothing in the analysis system.