利用沿河县2014年至2020年汛期(4~10月)含国家站在内的22个站点逐小时降水数据,统计分析沿河县汛期短时强降水时空分布特征,结果表明:1) 沿河县汛期短时强降水发生频次空间分布表现为西北和东南部高值区,中部低值区的特征,且存在三个高...利用沿河县2014年至2020年汛期(4~10月)含国家站在内的22个站点逐小时降水数据,统计分析沿河县汛期短时强降水时空分布特征,结果表明:1) 沿河县汛期短时强降水发生频次空间分布表现为西北和东南部高值区,中部低值区的特征,且存在三个高值中心,其降水强度空间分布表现为东强西弱,县东南部的高值中心主要以40 mm/h以上短时强降水为主;2) 沿河县汛期短时强降水高发期出现在6~7月,4月和10月为降水强度较弱月份,但平均降水强度却以5月和6月最大;3) 短时强降水日变化表现出明显的夜雨性:频发期主要集中在凌晨2时~次日早上9时,占总站次百分比的51%,且其强度分布表现为夜间降水大于白天;4) 60 mm/h以上强度的短时强降水主要出现在晚上21时~次日早上10时,累计站次达18站次,其余时次仅出现5站次,但早晨发生的短时强降水强度更大、站次更多,进一步表明沿河县短时强降水夜雨性的特征。Using hourly precipitation data from 22 stations including the national station in Yanhe County during the flood season from 2014 to 2020 (April to October), the spatiotemporal distribution characteristics of short-term heavy rainfall in Yanhe County during the flood season were statistically analyzed. The results showed that: 1) The spatial distribution of the frequency of short-term heavy rainfall during flood season in Yanhe County is characterized by high-value areas in the northwest and southeast, and low-value areas in the middle, and there are three high-value centers, whose spatial distribution of precipitation intensity is strong in the east and weak in the west, and the high-value center in the southeast of the county is mainly dominated by short-term heavy rainfall above 40 mm/h;2) The high occurrence period of short-term heavy rainfall in Yanhe County during the flood season occurred in June to July, and the rainfall intensity was weak in April and October, but the average rainfall intensity was the highest in May and June;3) The diurnal variation of short-term heavy rainfall showed obvious night rain: the frequent period was mainly concentrated from 2 am to 9 am the next day, accounting for 51% of the total station, and its intensity distribution was greater at night than during the day;4) The short-term heavy rainfall with an intensity above 60 mm/h mainly occurred from 21 pm to 10 am the next day, with a total of 18 stops, and only 5 stops in the rest of the day. However, the short-term heavy rainfall occurred in the morning with greater intensity and more stops, further indicating the characteristics of night rain of short-term heavy rainfall in Yanhe County.展开更多
通过近30 a逐日降水资料对印江、江口、松桃3县降水稳定性分析得出:(1)汛期降水的主要集中在5—7月;(2)汛期雨量在年际间表现不够稳定,雨涝年的汛期雨量是干旱年的2倍多;(3)按滑动10 d计算集中期,松桃降水集中期主要是6月1—10日、6月2...通过近30 a逐日降水资料对印江、江口、松桃3县降水稳定性分析得出:(1)汛期降水的主要集中在5—7月;(2)汛期雨量在年际间表现不够稳定,雨涝年的汛期雨量是干旱年的2倍多;(3)按滑动10 d计算集中期,松桃降水集中期主要是6月1—10日、6月22日—7月1日、7月10—19日;江口县降水集中期主要是6月29日—7月8日、6月1—10日、6月15—24日;印江降水集中期主要是6月18—27日、6月1—10日、7月15—24日。年际间降水集中期不稳定,需要常年做出预测。(4)印江、江口、松桃4月和10月有暴雨灾害出现,宜将当地的汛期定为4—10月。对长历时降水分析得出:(1)汛情的严重程度与4 d以内的长历时降水有较好的正相关,研究时长4 d以内的最大累积降水能反映汛情的基本情况;(2)依据经验频率,统计24 h、48 h、72 h和96 h共4个时长10 a 1遇、5 a 1遇、3 a 1遇的雨量情况,认为在无新增佐证的情况下,宜将3 a 1遇的降水量确定为长历时降水致灾风险阈值。展开更多
文摘利用沿河县2014年至2020年汛期(4~10月)含国家站在内的22个站点逐小时降水数据,统计分析沿河县汛期短时强降水时空分布特征,结果表明:1) 沿河县汛期短时强降水发生频次空间分布表现为西北和东南部高值区,中部低值区的特征,且存在三个高值中心,其降水强度空间分布表现为东强西弱,县东南部的高值中心主要以40 mm/h以上短时强降水为主;2) 沿河县汛期短时强降水高发期出现在6~7月,4月和10月为降水强度较弱月份,但平均降水强度却以5月和6月最大;3) 短时强降水日变化表现出明显的夜雨性:频发期主要集中在凌晨2时~次日早上9时,占总站次百分比的51%,且其强度分布表现为夜间降水大于白天;4) 60 mm/h以上强度的短时强降水主要出现在晚上21时~次日早上10时,累计站次达18站次,其余时次仅出现5站次,但早晨发生的短时强降水强度更大、站次更多,进一步表明沿河县短时强降水夜雨性的特征。Using hourly precipitation data from 22 stations including the national station in Yanhe County during the flood season from 2014 to 2020 (April to October), the spatiotemporal distribution characteristics of short-term heavy rainfall in Yanhe County during the flood season were statistically analyzed. The results showed that: 1) The spatial distribution of the frequency of short-term heavy rainfall during flood season in Yanhe County is characterized by high-value areas in the northwest and southeast, and low-value areas in the middle, and there are three high-value centers, whose spatial distribution of precipitation intensity is strong in the east and weak in the west, and the high-value center in the southeast of the county is mainly dominated by short-term heavy rainfall above 40 mm/h;2) The high occurrence period of short-term heavy rainfall in Yanhe County during the flood season occurred in June to July, and the rainfall intensity was weak in April and October, but the average rainfall intensity was the highest in May and June;3) The diurnal variation of short-term heavy rainfall showed obvious night rain: the frequent period was mainly concentrated from 2 am to 9 am the next day, accounting for 51% of the total station, and its intensity distribution was greater at night than during the day;4) The short-term heavy rainfall with an intensity above 60 mm/h mainly occurred from 21 pm to 10 am the next day, with a total of 18 stops, and only 5 stops in the rest of the day. However, the short-term heavy rainfall occurred in the morning with greater intensity and more stops, further indicating the characteristics of night rain of short-term heavy rainfall in Yanhe County.
文摘通过近30 a逐日降水资料对印江、江口、松桃3县降水稳定性分析得出:(1)汛期降水的主要集中在5—7月;(2)汛期雨量在年际间表现不够稳定,雨涝年的汛期雨量是干旱年的2倍多;(3)按滑动10 d计算集中期,松桃降水集中期主要是6月1—10日、6月22日—7月1日、7月10—19日;江口县降水集中期主要是6月29日—7月8日、6月1—10日、6月15—24日;印江降水集中期主要是6月18—27日、6月1—10日、7月15—24日。年际间降水集中期不稳定,需要常年做出预测。(4)印江、江口、松桃4月和10月有暴雨灾害出现,宜将当地的汛期定为4—10月。对长历时降水分析得出:(1)汛情的严重程度与4 d以内的长历时降水有较好的正相关,研究时长4 d以内的最大累积降水能反映汛情的基本情况;(2)依据经验频率,统计24 h、48 h、72 h和96 h共4个时长10 a 1遇、5 a 1遇、3 a 1遇的雨量情况,认为在无新增佐证的情况下,宜将3 a 1遇的降水量确定为长历时降水致灾风险阈值。
