Jiyang Zhang

Date of Award

January 2023

Document Type


Degree Name

Doctor of Philosophy (PhD)


Earth System Science & Policy

First Advisor

Haochi Zheng


Flood has caused tremendous life and economic losses over the past few decades and is expected to cause more in the future under the effects of climate change and socioeconomic development. With limited resources, cost-effective adaptation policies are urgently needed to minimize the economic and social impacts of future floods. The increasing flood losses and recent catastrophic flood events around the world expose two major issues of current flood adaptation schemes: 1) Flood risks are not well captured and predicted under climate change, leaving many communities unprepared for potential extreme flood events; 2) Current flood adaptation measures focus on the reduction of economic losses that mainly consists of property damages, and do not give adequate consideration to the social impacts in equity and human risks.

Focusing on the United States, this research aims to fill in the research gaps of the two flood adaptation issues mentioned above. First, an examination of observed snowfall trends from 1961 to 2017 in central North America shows that snowfall has increased in low-temperature areas in the northern part of the plains and high-elevation areas in the mountain regions, indicating that the interplay of climate change and topography can lead to increased flood risks in cold regions that should not be underestimated. Then, land acquisition, an emerging flood adaptation measure with high economic potential, is investigated for its economic and social performance under future flood risks for both itself and when combined with flood insurance. As a result, this research shows acquisition can be guided towards the low-income and highly populated areas to benefit the poorer populations, and can be further shifted towards areas with high flood insurance costs to reduce the total societal cost and the poorer homeowners’ cost of flood recovery. Together, these findings provide valuable implications on how flood adaptation approaches can be cost-effectively designed to tackle both economic and social challenges of future flood risks under changing climate.