拉萨市近50年大气压变化及对人体的影响

The variation characteristics of atmospheric pressure and its influence on human body in Lhasa in nearly 50 years

气压与人的身体健康、海拔高度等有着密切联系.众所周知,拉萨市地处青藏高原中部,平均海拔高,气压值低,在低压环境中氧气含量少,低氧会致使人体产生一系列不良反应(失眠、心肌缺氧等高原反应),这对进入高原的援藏职工、旅游爱好者、科研工作者等适应当地环境造成了极大的麻烦与困扰,为了降低低氧对人体造成的影响,更好地了解气压与人体健康的关系,本文采用1970到2018年拉萨市气象站点逐日平均气压监测数据,利用回归系数法、Mann-Kendall(M-K)非参数检验法、Morlet小波分析等方法分析了拉萨市近50年来大气压在时间尺度上的变化特征,研究结果表明:①拉萨市近50年平均气压和四季气压均呈现出上升趋势,其中春、夏两季平均气压与年平均气压上升趋势最为显著,秋、冬两季平均气压变化趋势较为平缓.②Mann-Kendall(M-K)非参数检验显示,拉萨市近50年平均气压分别在1978年和1985年发生突变,四季平均气压均在1970-1998年、2007-2014年这两个时间段内出现多个交点,且交点均通过了a=0.05显著性检验,表明突变显著.③从小波系数图(实部、模、模方)和小波方差图可以看出,近50年拉萨市大气压变化特征主要存在28年时间尺度的主周期.

The atmospheric pressure has a close relationship with altitude,health and so on.As is known to all,Lhasa is located in middle of the Tibetan plateau,the altitude is high and the pressure is low,Not only that,but the oxygen content is less in the low-pressure environment,Some symptoms,such as headache,insomnia,loss of appetite so tired breathing difficulties and other common plateau reaction caused by low oxygen levels.It is difficult for researchers,workers,residents,visitors to adapt to the local environment better.In order to weaken the impact of hypoxia on human body and furture understand the relationship between the atmospheric pressure and health.Based on observations recorded at automatic weather stations in Lhasa from 1970 to 2018,we studied the characteristics of atmospheric pressure variation at multiple time scales using the linear regression analysis,Mann-Kendall mutation test,morlet wavelet analysis and so on.The results showed that:(a)The annual mean pressure shows an upward tendency at a rate of 0.013hPa/a for the recent 50 years.Variation trends of mean pressure in different seasons were similar to that of annual mean pressure,but the variation range is bigger in spring and summer seasons than that in winter and autumn seasons.(b)By means of Mann-Kendall mutation test,we found that the annual mean pressure mutated in 1978 and 1985,respectively.There were several crossing points for seasonal mean pressure between the UF and UB curves in Lhasa from 1970 to 1998 and from 2007 to 2014,and passed the reliability test of significance levelα=0.05,this means there were abrupt changes and the variations were significant.(c)The maximum peak appeared in the temporal scale of 28years in Lhasa based on the real part isogram of wavelet transform coefficients and wavelet variance chart,it is explained that the first primary period is 28 years.The second primary period appeared in the temporal scale of 22 years.