# Evaluation of Urban Transportation Resilience under Extreme Weather Events
## 5 Results
### Comparison between Different Rainstorm Levels in the Same Subareas  
As can be seen in Figure 11, there was a significant difference in the perturbation of the transportation performance caused by different levels of rainstorms in the same subareas. During the red rainstorm warning, the rainstorm occurred during the daytime and there was an average delay of 4 h between the beginning of the rainstorm and the beginning of performance perturbation. In contrast, during the yellow rainstorm warning, the rainstorm occurred during the night and there was an average delay of 1 h. This implies that the urban transportation was more resilient during the day than at night. The reason for this may be that it was easier for transportation managers to mobilize resources during the daytime compared to the night. Second, the night rescue and relief teams were not well-dispatched and implemented.  
In addition, it can be seen from Table 2 that the recovery time for the transportation performance in the Cangshan and Jinan subareas during the yellow rainstorm warning was 5 h 5 min and 10 h 15 min, which was significantly longer than the 2 h 30 min and 1 h during the red rainstorm warning. The possible reason for this could be the relatively small number of emergency transportation managers and personnel in the Cangshan and Jinan subareas at night, and the lack of effective countermeasures to mitigate the effects of a rainstorm. Comparing the transportation resilience for different rainstorm levels in the three subareas, it can be seen that the transportation resilience in the Cangshan, Gulou, and Jinan subareas was 0.69, 0.82, and 0.83 during the red rainstorm warning, which was significantly lower than 0.93, 0.95, and 0.86 during the yellow rainstorm warning. This implies that the higher the rainstorm's level, the lower the transportation resilience in the three subareas.  
Notably, during the red rainstorm warning, the slope of the disruption phase and the lowest point of perturbation in the Jinan subarea were \(-\)0.23 and 0.72, which were more than those of \(-\)0.36 and 0.53 during the yellow rainstorm warning, which indicates that the disruption speed in the Jinan subarea was faster during the yellow rainstorm warning. Secondly, during the red rainstorm warning, the transportation resilience in the Jinan subarea was the highest among the three subareas, while during the yellow rainstorm warning, it was the lowest among the three subareas. This was probably because the rainstorm caused a large impact on the transportation in the Jinan subarea during the yellow rainstorm warning. The yellow rainstorm event attracted the attention of the Jinan District government, who formulated an emergency plan and took better countermeasures during the red rainstorm warning, such as cleaning the drainage outlet of Dengyun Road and unclogging the drainage pipes, taking traffic restriction control of Helin Road, and filling the drainage pipes on Chongan Road to reduce the impact of the rainstorm on the transportation. This proves that the transportation performance in the Jinan subarea during the red rainstorm warning was improved by 36% compared to the yellow rainstorm warning by formulating an emergency plan and taking mitigation measures.