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Contradictions between population distribution and socio-economic development has been taken as a major topic regarding to the realization of coordinated growths of resource, society, economy and ecosystem, especially in city region. Water resources carrying capacity (WRCC) can reflect the quantitative relationship between the total regional population, economic scale and the volume of water resources, which can objectively demonstrate the regional water consumption level under a certain scale of population and economy. Indices of WRCC (WCC and WCCI) were applied to analyze the WRCC of Ningbo city, based on the relationship between population size and water resources of Ningbo city. WCC and WCCI can effectively solve the uncertainty among the total regional population, economic scale and the volume of water resources. Because of different trends in counties, there are different WRCC in these counties. Time-series and multi-scales of WRCC in Ningbo city were assessed using geographic information system (GIS) method. Also, the future WRCC and its regional variation of Ningbo city in 2020 and 2030 were analyzed based on the practical situations using scenario analysis method. Results showed that in the presence of water resources volume of Ningbo city fluctuated, affected by water resource endowment in the past 15 years, the entirety of Ningbo city of WRCC was from abundance to surplus, then surplus with relatively high, and when the flow year was from high flow years to normal flow years, then to low flow years. In terms of the differences of the WRCC among counties, the various WRCC grades of prefecture-level counties should need different kinds of strategies during different flow years to reach their stable states because that in average flow years, water resources existed surpluses beyond balance in Cixi (county-level) city and Ningbo city municipal district. In low flow years, critical overload happened in both Cixi city and Ningbo city municipal district. In the context of the year of 2020 and 2030, the overall WRCC of Ningbo city would stay in abundant levels, whereas the contradictive relationship between population and water resources would be fairly remarkable.

In this study, the performance of 33 Coupled Model Intercomparison Project 5 (CMIP5) global climate models (GCMs) in simulating precipitation over the Tibetan Plateau (TP) was assessed using data from 1961 to 2005 by an improved score-based method, which adopts multiple criteria to achieve a comprehensive evaluation. The future precipitation change was also estimated based on the Delta method by selecting the submultiple model ensemble (SMME) in the near-term (2006&ndash, 2050) and far future (2051&ndash, 2095) periods under Representative Concentration Pathways (RCP) scenarios RCP4.5 and RCP8.5. The results showed that most GCMs can reasonably simulate the precipitation pattern of an annual cycle, however, all GCMs overestimated the precipitation over TP, especially in spring and summer. The GCMs generally provide good simulations of the temporal characteristics of precipitation, while they did not perform as well in reproducing its spatial distributions. Different assessment criteria lead to inconsistent results, however, the improved rank score method, which adopts multiple criteria, provided a robust assessment of GCMs performance. The future annual precipitation was projected to increase by ~6% in the near-term with respect to the period 1961&ndash, 2005, whereas increases of 12.3% and 16.7% are expected in the far future under RCP4.5 and RCP8.5 scenarios, respectively. Similar spatial distributions of future precipitation changes can be seen in the near-term and far future periods under the two scenarios, and indicate that the most predominant increases occurred in the north of TP. The results of this study are expected to provide valuable information on climate change, and for water resources and agricultural management in TP.

Climate change affects regional agricultural development, but a quantitative assessment of large-scale impacts remains difficult. Northwest China has experienced considerable climate change during the last 40 years, and this study uses GIS technology to evaluate the impacts of that change on the agricultural water balance. Results show that over the last 40 years the climate has transitioned from a warm-dry to a warm-wet pattern in the northwestern area of Northwest China, while exhibiting a pattern of increasing aridity in other parts of the region since the 1980s. Through analysis of the spatio-temporal distribution of agricultural water balance using water cycle models that include climatic, crop and cropland layers, we found that the climate warming in the northwestern area of the region has led to a notable reduction in the agricultural water deficit. This reduction, however, still cannot significantly alleviate the water deficit. Finally, we argue that to make agricultural development sustainable in this area, both hard and soft approaches are needed to bring about efficient use of the limited water resources.