极端事件与影响评价:赞比亚干旱对其社会经济之影响(英文)

Objective--To investigate the effects of extreme events such as floods and droughts on social and economic activities in Zambia. Methods--The annual daily rainfall for stations, which have complete 40 years （1960-2000） time series of daily rainfall, is assigned to one of the five classes. class 1 （0-0.5 ram）, class 2 （0.5-5 mm）, class 3 （5-10 mm）, class 4 （10-25 ram） and class 5 〉25 ram）. Class 1 refers to dry days or nearly dry days where as classes 2 to 5 refer to wet days. Class 5 refers to high intensity rainfall days. The daily rainfall for the three Agro-Ecological zones is computed by averaging the daily rainfall of all the meteorological stations falling in each zone. Simple linear regression is performed to establish trends for the variables namely （i） annual number of days in each of classes from two to five, （ii） annual number of wet days and （iii） annual rainfall amount, for individual stations as well as for the three eco-climate zones. The student＇s t -tests are carried out to determine the significance of trends. The level of significance used in the trend analysis is set to 0.10. Results--This paper dwells on the drought trend in Zambia and its social and economic ramifications as it is exposed to the crises, stress and shocks arising from the fluctuating weather conditions. The food system in Zambia which has developed since the colonial period and has persisted even after the attain- ment of political independence in 1964 is increasingly becoming vulnerable to environmental shocks be- cause of the climate change and variability as maize the main staple food is more susceptible to extreme weather events as shown in this analysis of drought events. Trends for annual number of days in clas- ses three and four for all analyzed data are found to be negative indicating that days with rainfall intensity of 5-25 mm are decreasing at each of analyzed individual station and also in the three agro-ecological zones. Annual numbers of days of low intensity rainfall （0.5~-10 mm） in zone 1 are increasing pointing drier conditions. Annual number of days of high intensity rainfall （〉25 mm） are increasing in zones 2 and 3 indicating flooding conditions. Conclusion--Results have shown that drought can have dramatic deleterious effects on a country＇s socioeconomic, ecological as well as having some political ramifications as it affects stable flow of finances to government projects. For a small and intermediate economy like Zambia＇ s, it is very susceptible to draught episodes, because it is driven hy a large agricultural sector. That is, food availability and prices, employment, access to imports, government expenditures, availability of social services, and credit sources are all affected by drought.

Extreme events and impact assessment:social and economic impacts of drought in Zambia