**5. Discussion**

This chapter is to use spatial data to comprehensively evaluate and analyze the vulnerability of major megalopolise, and to realize visualization in the map, which better reflects the distribution law of urban vulnerability, and proposes a response to urban vulnerability. In this chapter, the three megalopolise vulnerability show that the more developed the urban economy, the higher the vulnerability index. This is an interesting and very thought-provoking discovery. We think this research is valuable because we have seen the urban vulnerability in the most economically developed regions of China, where the core cities are connected to other cities by elements, industries and infrastructure. And the results show that the more developed the city is, the higher the vulnerability will be. Therefore, in the medium and long term development of China in the future, how to overcome the vulnerability and continuously enhance the resilience of megalopolise should be further put forward countermeasures. In fact, as infrastructure integration and city-to-city connectivity grow, so does vulnerability. From the perspectives of government, industrial layout, elements flow, wage and welfare, etc., it is also a question that needs further thinking about how to deal with the increasing risks in the future megalopolise in the form of layout, industrial (employment) structure and welfare growth.

Due to the limitation of data access, some descriptive indicators of urban vulnerability have not been introduced into the evaluation system, which limits the research conclusions. In the follow-up, multi-source heterogeneous data should be collected to strive for more accurate and comprehensive evaluation results.

The follow-up research needs to use regional climate simulation or statistical downscaling methods to predict regional climate change, and comprehensive simulation results provide suggestions for each city group.
