ABSTRACT The urban population of the world houses almost 13% in low-elevation coastal zone (LECZ). Major cities with a population of more than 5 million, which account for almost two-thirds of the world's large cities, reside in low-elevation coastal zones. These areas house some of the most important socioeconomic activities, and they are also environmentally delicate. According to the IPCC 2007 report, there will be an 8–88 cm rise in sea level between 2000 and 2100 AD, which will have an unpredictable and massive impact on land up to 9 m elevation above MSL. This study discusses the rise in sea level, climate vulnerability, and future problems using elevation-based GIS analysis, accomplishing socioeconomic vulnerability and exposure. The statistics suggest that more than 26% of the population lies within a 9 m contour interval, whereas a 20 m contour accommodated 81% of the total population. In figures, it is estimated that over 1,632,200 people by 2011 which is expected to rise to 4,048,894 people by 2050 are exposed to 100-year flood events. Thus, the study clinched that a significant number of people in Surat confront flooding due to the extreme rise in water level during this period.