[ Objective] The research aimed to study climatic characteristics of hail and dsk zoning of its disaster factor in Anhui Province. [Method] Based on the hail-day records from 82 weather stations in Anhui Province, Chi...[ Objective] The research aimed to study climatic characteristics of hail and dsk zoning of its disaster factor in Anhui Province. [Method] Based on the hail-day records from 82 weather stations in Anhui Province, Chinese Meteorologica/Disaster Dictionary （1951 to 2005） and The Yearbook of Meteorological Disaster in Anhui Province （2006 to 2009）, we discussed the climatic characteristic and dsk zoning of hail disaster in Anhui Province. [Result] The hail days exhibited significant interdecadal variability, and it had a significant negative correlation with annual mean minimum temperature. The hail usually occurred from March to August, most frequently in June but less in autumn and winter. It most likely took place from aftemoon to sunset. The spatial distribution showed that the hail occurred more in northeast of Huaibei, south of Dabie Mountain and some areas of Huangshan Mountain, but less in Jianghuai region. The index of hail intensity was defined by three factors, the diameter, duration and gust grade, and the percentile method was used to grade the intensity of the hail disaster. This work provided a possibility for quantitative assessment of the intensity of hail disaster. The results of hail disaster risk zoning in Anhui Province showed that high dsk zones were concentrated in northeast of Huaibei, and low risk zones were mainly in south of Huaihe River. Finally, vedfied by historic disaster, it showed that the results of risk zoning had a certain rationality and feasibility. Conclusion The research could provide reference basis for hail disaster defense and assessment.展开更多
The objective here is to assess the atmospheric evaluations with respect to the perilous hailstorm phenomenon in Tehran. To accomplish this study, the available data regarding 9 (WW) present weather codes that reveal ...The objective here is to assess the atmospheric evaluations with respect to the perilous hailstorm phenomenon in Tehran. To accomplish this study, the available data regarding 9 (WW) present weather codes that reveal the hailstorm phenomenon with different intensities in 3 hrs observations for 6 meteorological stations of Tehran and vicinity for the period between 1985-2015 are applied. It is revealed that hail occurrence in Tehran is at its maximum in transition seasons of spring and fall between the hrs. 6 - 18 (UTC). It is found that the instability indexes intensify in the afternoon with a higher atmospheric flotation indicative of the possibility in occurrence of thunder hailstorm. Synoptic assessments point to the fact that the synoptic pattern created this thunder storm due to expansion of two: low-pressure cores over Arabia and North-Europe and the cold high-pressure over South Russia with a NS orientation have developed an intense pressure gradient over Tehran province. The study area being located at the left exit of sub-tropical jet stream has made a Baroclinic atmosphere condition on Tehran province. Access to great humidity resources of Mediterranean and Black seas and a drastic decrease of temperature at the upper level of the cloud verifies the hail occurrence on March 30th of 2015 in Tehran.展开更多
基金Supported by Special Project of Science Research in Public ServiceIndustry(Meteorology),China(GYHY200906019)
文摘[ Objective] The research aimed to study climatic characteristics of hail and dsk zoning of its disaster factor in Anhui Province. [Method] Based on the hail-day records from 82 weather stations in Anhui Province, Chinese Meteorologica/Disaster Dictionary （1951 to 2005） and The Yearbook of Meteorological Disaster in Anhui Province （2006 to 2009）, we discussed the climatic characteristic and dsk zoning of hail disaster in Anhui Province. [Result] The hail days exhibited significant interdecadal variability, and it had a significant negative correlation with annual mean minimum temperature. The hail usually occurred from March to August, most frequently in June but less in autumn and winter. It most likely took place from aftemoon to sunset. The spatial distribution showed that the hail occurred more in northeast of Huaibei, south of Dabie Mountain and some areas of Huangshan Mountain, but less in Jianghuai region. The index of hail intensity was defined by three factors, the diameter, duration and gust grade, and the percentile method was used to grade the intensity of the hail disaster. This work provided a possibility for quantitative assessment of the intensity of hail disaster. The results of hail disaster risk zoning in Anhui Province showed that high dsk zones were concentrated in northeast of Huaibei, and low risk zones were mainly in south of Huaihe River. Finally, vedfied by historic disaster, it showed that the results of risk zoning had a certain rationality and feasibility. Conclusion The research could provide reference basis for hail disaster defense and assessment.
文摘The objective here is to assess the atmospheric evaluations with respect to the perilous hailstorm phenomenon in Tehran. To accomplish this study, the available data regarding 9 (WW) present weather codes that reveal the hailstorm phenomenon with different intensities in 3 hrs observations for 6 meteorological stations of Tehran and vicinity for the period between 1985-2015 are applied. It is revealed that hail occurrence in Tehran is at its maximum in transition seasons of spring and fall between the hrs. 6 - 18 (UTC). It is found that the instability indexes intensify in the afternoon with a higher atmospheric flotation indicative of the possibility in occurrence of thunder hailstorm. Synoptic assessments point to the fact that the synoptic pattern created this thunder storm due to expansion of two: low-pressure cores over Arabia and North-Europe and the cold high-pressure over South Russia with a NS orientation have developed an intense pressure gradient over Tehran province. The study area being located at the left exit of sub-tropical jet stream has made a Baroclinic atmosphere condition on Tehran province. Access to great humidity resources of Mediterranean and Black seas and a drastic decrease of temperature at the upper level of the cloud verifies the hail occurrence on March 30th of 2015 in Tehran.
