摘要
基于国家气象信息中心发布的622个气象站点1960—2013年的降水量、气压、气温、水汽压和相对湿度等日数据及249个气象站点2013年8月25日至9月25日02、08、14和20时数据,利用中国气象局、Barnes和(Georgakakos的经验公式来计算抬升凝结高度从而近似降水云云底高度,归纳出中国降水云云底高度的时空分布特征。结果表明:(1)在整体、季节(除冬季外)、小时和降水量等级为Ⅰ级(P<10mm)、Ⅱ级(10 mm≤P<25 mm)时的空间分布特征基本一致,即自东南向西北逐渐增高,没有显著的年际差异。(2)区域差异显著,就四大自然区(北方地区、南方地区、西北地区和青藏高原地区)而言,青藏高原地区和西北地区的降水云云底高度高于平均云底高度,且除青藏高原地区外其他地区的云底高度呈逐年下降的趋势。(3)从季节差异看,春、夏季的降水云云底高度高,冬季的云底高度最低。(4)日变化明显,08时的降水云云底高度最低,14时最高。(5)利用三种算法算出中国降水云云底高度和降水量的相关系数分别是-0.47、-0.46、-0.44,中国云底高度和相对湿度的相关系数分别是-0.81、-0.81、-0.79,均呈负相关。
Based on daily data of precipitation, air pressure, temperature, average vapor pressure and average relative humidity in 622 stations released by the National Meteorological Information Centre of China during 1960-2013 and the data collected at 02:00, 08:00, 14..00 and 20:00 BT from 25 August to 25 September 2013 by 249 stations, the algorithms of China Meteorological Administration, Barnes and Georgakakos are applied to calculate the height of lifting condensation level to approximate height of precipitation cloud base, and then the spatio-temporal distribution characteristics of cloud base height in China are analyzed. The results indicate that (1) the spatial distribution of precipitation cloud base heights on the annual, seasonally and hourly bases show consistent with precipitation levelsⅠ and Ⅱ. The cloud base height gradually increases from southeast to northwest, and the interannual difference is not significant. (2) The regional difference is significant. In term of four nature zones in China (North, South, Northwest and the Tibetan Plateau), the precipitation cloud base heights of the Northwest and the Tibetan Plateau are higher than the national mean. The base height decreases gradually year by year except the Tibetan Plateau. (3) Seasonally, the precipitation cloud base height in spring and summer is higher, and the lowest is in winter. (4) Diurnal variation of the precipitation cloud base height is significant and the lowest at 08:00 and the highest is at 14.00. (5) By using the three algorithms, the correlation coefficients between the cloud base height and precipitation are -0.47, -0.46 and -0.44, and between the cloud base height and relative humidity are -0.81, -0.81 and O. 79, respectively.
出处
《气象》
CSCD
北大核心
2016年第9期1135-1145,共11页
Meteorological Monthly
基金
国家自然科学基金项目(41461003)
全球变化国家重大科学研究计划项目(2013CBA01801)共同资助
关键词
抬升凝结高度
云底高度
时空分布
地面资料
lift condensation height, cloud base height, spatio temporal distribution, surface observationdata