Towards a climate resilient transportation system : a case study in Hong Kong

Abstract

Urban transportation systems serve as crucial parts in people’s daily life by transmitting passengers and goods. Their performance can be affected by many factors including climate events. According to the historical data from the Hong Kong’s Observatory, the main impacts of climate change include the increase of temperature, precipitation and sea level; furthermore, extreme weather events such as extreme precipitation events, tropical cyclones occur more frequently and severely. Extensive studies have been done on the resilience of single mode transportation networks. However, climate resilience of a transportation system with multiple modes has not been examined in the literature. The goal of this thesis is to assess the climate resilience of a multi-modal transportation network and examine its potential recovery solutions under different extreme weather events. Three major works have been conducted to achieve this goal. First, the climate change’s impacts on Hong Kong’s transportation system have been examined, based on which a general framework for climate resilient transportation system is developed. Second, a simulation-based framework is proposed to examine the performance of multi-modal transportation systems with consideration of different situations and recovery solutions. Third, a scenario-based climate resilience analysis is conducted for a multi-modal transportation network in Hong Kong; different situations and recovery solutions are examined with the simulation results. Some conclusions can be drawn from the studies above. First, the climate change leads to more extreme weather events like tropical cyclones and rainstorms in Hong Kong, and the climate resilience of Hong Kong’s transportation system relies on the performance of Hong Kong’s transportation under these extreme events. Second, extreme weather affects the capacity of public transport (supply) and the needs of passengers (demand). In general, the extreme weather can degrade the performance of public transportation, while in some extreme conditions, the performance may increase due to the sharply decreased travel demand. Third, the origin transfer method can help improve the performance of public transport system under extreme weather events; transfer during the trip is able to enhance the performance of public transportation network significantly; but in some scenarios, it may not be as efficiency as origin transfer method. The contributions of this thesis are: 1) a general framework to analyze the climate resilience of multi-modal transportation systems, 2) a simulation-based approach to measuring the performance of multi-modal transportation systems, and 3) introducing cost incentives as a means of transportation guidance for implementation of recovery solutions under extreme weather events.