A Study Of The Complex And Nonlinear Investigation Of Climatological-hydrological Process In The Tarim River Basin

Global warming has currently accelerating in the troposphere and one of the consequences that derived from climate change is the chaotic variations of weather and water cycle on the earth surface. Extreme weather events have been observed all over the world, particularly for the pattern and intensity of climatological-hydrologic-al process. The Tarim River Basin, a typical arid area, is a sensitive area of climatological-hydrological change; many researchers have launched a lot of research and discussion about it. It seems evident that the understanding of the complex dynamic characteristics of climatological-hydrological process can contribute to developing advanced techniques for climatological-hydrological forecasting. The accurate forecast can help to develop effective warning strategies to reduce impacts on climatological-hydrological environment.Climatological-hydrological system is composed by several subsystems, and by the interaction of multi spheres, multi factors, multi scale. One or more ways can be internal or external interaction among subsystems, which result in interaction structure of more complex form not only in the time, but also in the space. The results form complex-huge system with oppression outside and nonlinear dissipative inside, and the whole show its complexity. There are many influence factors of climatological-hydrological system, for example, human activities, geographical location, complex surface characteristics and so on. But these factors are not independent of each other, but there are nonlinear interactions at various spatial and temporal scales. These reasons result in which the time evolution process of climatological-hydrological process shows inherent nonlinear and external complex characteristics.For the above question, the author has introduced the fractal theory, chaos theory, complex network theory and GIS technology to study complexity and nonlinear characteristics of regional climatological-hydrological process. On this basis, the authorinvestigates the temporal evolution dynamics of the process further. At last, the author sets up the self-organized critical theory of regionalclimatological-hydrological factors, and interprets the fractal structure of regional climatological-hydrological process.The main works and conclusions in this study are as follows:1. Firstly, the long memory and scaling properties of average daily temperature, precipitation, relative humidity, evaporation and daily runoff of Kaidu River are investigatedby rescaled range analysis (R/S), detrended fluctuation analysis (DFA) and spectral analysis. The results show that the temporal scaling behaviors in the five series all exhibit two different power laws. In shorter temporal scaling, all series indicate thesimilar persistence corresponding to the annual cycle. However in longer temporalscaling, the trends are different for the five series, which reflect the different inherentdynamic nature of various climatological-hydrological factor series. The fluctuations of Hurst exponent, DFA exponent and power spectrum exponent with increasing the threshold magnitude are analyzed. Secondly, long-range cross correlations between each pair of five indices are revealed by the Detrended Cross-Correlation Analysis method (DCCA). We find that the double logarithm curve F2(s)～s two or even three scale-invariant regions are presented. Lastly, Supported by the GIS technical and based on the CoKriging method, the space distribution for the degree of long memory for climatological-hydrological process in Tarim River Basin is analyzed.2. According to chaos theory, through reconstructing the phase-space for the series of average daily temperature, precipitation, relative humidity, evaporation and daily runoff of Kaidu River in Tarim River Basin, and calculates their three characteristic quantities, including the maximum Lyapunov exponent λ1, Kolmogorov entropy K and the correlation dimension D, with Rosenstein and G-P algorithm respectively. All results show obvious chaotic and fractal characteristics in the five series, which are the result of the evolution of non-linear chaotic dynamic system. The climatological-hydrological process in the Tarim River basin also has deterministic and stochastic characteristic. Supported by the GIS technical and based on the CoKriging method, the space distribution for the degree of chaotic and complexity for climatological-hydrological process in Tarim River Basin is analyzed. We find that the bigger for the values of three characteristic quantities is, the stronger the chaotic and complexity are in region with complicated climate change is, runoff and higher altitudes. However, the values of three characteristic quantities are smaller in desert hinterland, which the chaotic and complexity is weaker. Furthermore, the lower (higher) the correlation dimension D, the higher (lower) the level of the system, and the more obvious (less obvious) the trend. The different the maximum Lyapunov exponent λ1indicate that there are significant differences for five series in the the maximum forecasting scale. Specifically, the bigger λ1, the longer the scale is and the smaller λ1, the shorter the scale is. And the average degree of butterfly effect of climatological-hydrological factor system shows average daily relative humidity> average daily temperature>daily precipitationdaily evaporation, as for annual runoff, Hotan River>Yerqiang River>Akesu River(?)Kaidu River.3. Multi-fractal methods (multi-fractal box counting method) has been applied to analyze the five climatological-hydrological factor series. It shows that the method can not only identify the scaling invariance but also explain the scaling behavior of the probability distributions in the factor time series. Multifractal characteristics of the five factor series can be described by three multi-fractal parameters, namely B,△α and△f. Further, multifractal characteristics changes of every age are analyzed, combining with the climate and hydrological changes of the Tarim River basin. Lastly, Supported by the GIS technical and based on the CoKriging method, the space distribution for the degree of multifractality of climatological-hydrological process in Tarim River Basin is analyzed. 4. To analyze the dynamics of the climatological-hydrological process in Tarim River Basin, using homogenous partition of coarse graining process, the series of average daily temperature, precipitation, relative humidity, evaporation and daily runoff of Kaidu River is transformed into symbolic sequences consisting of5characters{R, r, e, d, D}. The vertices of the Temperature fluctuant network (TFN), Precipitation fluctuant network (PFN), Relative humidity fluctuant network (HFN), Evaporation fluctuant network (EFN) and Runoff fluctuant network (RFN) are1253-symbol strings (i.e.,125fluctuation patterns in durations of3days), respectively, linked in the networks’topology by time series. They contain integrated information about interconnections and interactions between fluctuation patterns of temperature, precipitation, relative humidity, evaporation and runoff in networks’topology. We calculate the dynamical statistics of the degrees and the distribution of degrees, clustering coefficient and the shortest path length, and compared the difference of these five series from the view point of network. The result shows that the five factor fluctuant networks have good clustering characteristic with obvious characteristic of community structure and shorter average path length. TFN and RFN are scale-free and small-world network with degree distribution obeying a three and double power law, respectively, and with obvious characteristic of local community structure. PFN, HFN and EFN are also scale-free and small-world networks with obvious characteristic of scale-free and small-world effect.We also find some vertices’ degrees are remarkably high, for example, there are more RRR, dRR, ReR..., which shows these occurrence probabilities of the climatological-hydrological factor fluctuation represented by these5nodes, is greater. Furthermore, the main vertices of each one of TFN, HFN and EFN generally contain the2characters R and r, and the main vertices of both RFN and PFN generally contain r and e, which shows that all the five factors are is mainly ascending, however, the temperature, relative humidity and evaporation are rising faster than the precipitation and runoff of Kaidu river. Futher, some vertices in the five factor fluctuant network have high betweenness centrality (BC),4%,3.2%,3.2%,0.8%and3.2%of vertices bear19.71%,19.71%,13.64%,3.4%and13.88%of betweenness centrality of networks, respectively, these vertices of importance in topological statistics are helpful to understanding the inherent law and information transmission.Lastly, supported by the GIS technical and based on the Geostatistics theory, the space distribution for the degree of complexty by the average daily temperature, precipitation, relative humidity, evaporation fluctuant networks of climatological-hydrological process in Tarim River Basin is analyzed. From the distribution graph of the average degree of these5nodes in all the23meteorological stations, we define them by the symbols as the Tarim River Basin wide model, the first-level-degree area, the second-level-degree area and the third-level-degree area. The distribution of the average degree, similarity coefficient, cluster coefficient and average shortest path have a regional characteristics, which provide us with the feasibility for analyzing the regional climatological-hydrological characteristics intheory.5. Firstly, the frequency-intensity distribution of five climatological-hydrological factors suggest there are inherent dynamical connection between small factor change and extreme weather events. Then, a numerical sandpile model with decay coefficient is constructed to revealinherent dynamic mechanism of climatological-hydrological process revolution. In this model, changing the number value of decaycoefficient, the frequency-intensity distribution of various factor values can be simulated. And all results are consistent with the actual data very well. Simulating computation shows that the factors act as dynamically self-organized systems and it is the self-organized criticality of the climatological-hydrological processes that results in the temporal variation of the processes.