基于1973-2015年间的全球综合无线电探空资料(IGRA),采用总体理查逊数(Bulk Richardson Number)方法,分析了北极扬马延岛43年间的大气边界层高度变化特征,并对其多年月均大气边界层高度变化以及年均大气边界层高度变化进行深入分析探讨.结果显示,扬马延岛白天对流边界层高度高于夜晚稳定边界层高度,夏季多年月均大气边界层高度远低于冬春季节的高度,夏季平均高度仅为262 m,而冬春季节高度在600 m附近.大气边界层高度的变化与地面相对湿度的变化呈现较好的反相关关系.由于受到墨西哥湾暖流的影响,岛屿全年温差较小,夏季的相对湿度较大,导致潜热通量较多,抑制了边界层内的对流过程,造成夏季大气边界层高度较低.此外,其年均高度在1973-1988年间出现波动下降,而后在1988-1995年快速上升,最后于1995-2015年间变化平稳.%Based on 43 years' data of twice-daily radiosonde observations, this study investigated the temporal variability of the planetary boundary layer height (PBLH) at Jan Mayen, Norway, based on the Bulk Richardson Number method. It was found that the PBLH during daytime was higher than at night for most months. In addition, the monthly averaged PBLH in summer (around 262 m) was found much lower than in spring or winter (about 600 m). The PBLH variations showed good anticorrelation with surface relative hu-midity. Because of the influence of the Gulf Stream, the annual temperature difference at the Jan Mayen sta-tion is quite small and the surface temperature shows little seasonal variation. Surface relative humidity ex-hibits considerable seasonal variation, with a maximum value in summer and a minimum value in winter. The higher humidity in summer causes higher latent heat flux that restrains the convective process in the boundary layer, which leads to the lower summer PBLH. The long-term changes in PBLH at the studied sta-tion also revealed some interesting results. The annual mean PBLH decreased from 1973 to 1988, increased rapidly between 1988 and 1995, and then fluctuated between 500 and 600 m after 1995.
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