The purpose of the thesis research is to determine how susceptible the ecosystems in the city of İzmir are to the effects of climate change and provide relevant data to policymakers so that they could develop more efficient climate change adaptation measures. İzmir city is facing challenges in addressing the vulnerabilities triggered by climate change. The biophysical components that contributed to ecosystem vulnerability in the city include the urban heat island effect, urban pluvial floods, and coastal floods. These components were evaluated using a stringent approach that utilized the most recent findings from scientific research and various technological instruments. The analysis results were provided to portray the parts of the city that were most susceptible to the effects of climate change, and the results were further evaluated to better comprehend the processes that contributed to intensifying the consequences of climate change for the vulnerable regions. A thorough investigation and in-depth inspections were carried out using representative tiles from the city, and the results showed that existence of tree and green areas, imperviousness density, Footprint Ratio, Floor Surface Index, and road ratio were the most contributing factors of climate change vulnerability. Following the process of analysis, a systematic of planning and planning parameters were developed that embraced nature-based solutions and a performance-based planning approach for enabling the adaptation of settlements to climate change. The findings contributed significantly to the expanding body of knowledge on how to adapt to the effects of climate change and provided suggestions for efficient measures to mitigate the related risks in İzmir. Keywords: Climate Change, Ecosystem Services, Nature-Based Solutions, Performance-Based Planning, Urban Heat Islands, Urban Pluvial Floods, Coastal Floods.