海平面上升对珠江三角洲洪潮水位影响的研究

Investi gation on the Effect of Rise of Sea Level on Flood and Tidal Stagein the Pearl River Delta

建立珠江三角洲及河口湾一、二维不稳定流连接数学模型 ,假定珠江河口治理规划已全面实施并完成 ,然后针对典型洪潮年的水文条件 ,分析计算海平面上升 10～ 3 0cm后珠江三角洲地区洪潮水位的变化。经过“94·6”洪水过程模拟计算 ,得出海平面上升后 ,珠江三角洲中下游地区洪水位将上升 5～ 2 9cm ,以河口附近地区上升值最大 ,向上游逐渐减小 ,同时潮流河口上升值大于径流河口。经过“93·9”、“74·7”台风暴潮模拟计算 ,得出海平面上升后 ,珠江三角洲中下游地区风暴潮水位将上升 11～ 3 4cm ,口门附近上升值最大。经过 3种洪潮年型最高水位组合模拟计算 ,得出海平面上升 3 0cm后 ,珠江河口八大口门除崖门和虎跳门外 ,其它 6个口门潮水位将高出 5 0年一遇潮水位 12～ 4 3cm。

The 1-and 2 -dnon -steadyflowconnectionmathematicalmodelforthePearlRiverDeltaandestuarinebayissetup . AssumedthattheimprovementplanofthePearlRiverEstuaryhasbeenimplementedandcompleted ,authorsanalizeandcalculatethe changeoffloodandtidalstageinthedeltaareaafterthesealevelraisesby 10～ 3 0cminaccordancewiththehydrologicconditionsof thetypicalfloodandtidalyear.BytheanalogcomputationoffloodhydrographoccurringinJune 1992 ,floodstageinlowerandmiddlereachesofthedeltawillraiseby 5～ 2 9cmaftertheriseofsealevel.Thevalueofrisewillbemaximuminareaneartheestuaryand decreasegraduallytowardstheupperreaches.Thevalueofriseintidaloutletswillbegreaterthanthatinrunoffoutlets.Bytheanalog computationoftyphoonsurgeoccurringinSeptember 1993andJuly 1974respectively ,windtidestageinlowerandmiddlereachesof thedeltawillraiseby 11～ 3 4cmaftertheriseofsealevel,withthemaximumvaluebeingintheareaneartheestuary .Bytheanalog computationofmaximumstageof3 patternsoffloodandtidalyears ,afterthesealevelrisesby 3 0cm ,floodstagein 6outlets (exclud ingYamenandHutiaomen)willbe 12～ 4 3cmhigherthanthatof 5 0 - yearfrequency .