大连市气候变化适应度评价

An Assessment of Adaptation to Climate Change in Dalian

选取大连市1960年-2009年月平均气温和降水量资料,运用线性倾向估计和Morlet小波分析探讨了近50a大连市气候变化特征,表明50a来年均气温显著上升,其中冬、春季的增幅最大,降水量总体上呈下降趋势,基本经历了"减少-增加-减少-增加"的变化过程。在此背景下,根据系统之间的动态耦合原理,选取社会、经济、农业和资源环境系统作为大连市气候变化适应度的评价子系统,利用主成分分析法,确定2000年-2009年气候系统与评价系统的综合发展水平,然后运用模糊数学中的隶属度函数,判定大连气候变化的适应度。结果表明:2000年-2009年大连市气候系统的综合发展水平波动性较大,但总体上处于上升态势,评价子系统的发展水平也显著提高,而且两者具有明显的阶段性特征;2000年-2009年大连市气候变化的适应度总体上呈微弱的下降趋势,尤其是从2007年开始,下滑程度较大。

Climate change in Dalian was examined by the linear trend method and wavelet analysis based on mean monthly temperature and precipitation data during the period 1960-2009.It was found that annual mean temperature increased obviously at an overall rate of 0.28℃/10a over recent 50 years,with the rising amplitude greater in winter and spring.Precipitation generally decreased at a rate of 23.27 mm/10a in terms of inter-decadal changes which exhibited a trend of ＂decreasing-increasing-decreasing-increasing＂.In terms of the principle of dynamic coupling among systems,society,economy,agriculture,resources,and the environment system were taken as the subsystem for assessment of adaptation to climate change.Firstly,comprehensive development levels of the climate system and subsystems during the period 2000-2009 were calculated by principal component analysis（PCA）.Then the adaptation degree of climate change in Dalian was determined by the function of membership grade in fuzzy mathematics.Results show that the comprehensive level of the climate system fluctuated greatly but generally increased.The development levels of the assessment subsystem also showed rising trends.Moreover,notable stage characteristics were observed.The comprehensive level of the climate system and four assessment subsystems were all lower,but the former was higher than the latter during the period 2000-2004.The development level of all increased prominently,but the former was lower than the latter during 2005-2009.The adaptation degree of climate change in Dalian relative to evaluation subsystems fluctuated,exhibiting a generally decreasing trend relative to the society development and the environment quality,yet an increasing trend relative to agriculture and economy development before 2007 and then rising rapidly.However,the adaptation degree of economy, society,agriculture,and the environment subsystem relative to the climate system generally decreased,with descending amplitudes of 0.7,0.8,0.9,and 1.1,respectively.On the whole,the adaptation degree of climate change showed a marginally declining trend during the period from 2000-2009.The major reasons are as follows.There were 6 years with shortage of rainfall since 2000,which significantly threatened industrial and municipal use of water and agricultural production.Because of continuous drought,graduate increases in the amount of exploited groundwater led to declining ground water levels and expanding of the area of seawater invasion. In addition,rising winter temperature would be good for insects to live through winter,which could result in increasing number of insects of incoming summer and more use of pesticide and herbicide.Finally,various extreme weather events would become more frequent under climate warming.