The low lying Indian Sundarban delta (ISD) is highly susceptible to multiple coastal hazards and disasters. The increasing frequency and intensity of natural hazards have been influenced by global climate change and devised an additional burden for coastal dwellers to sustain their livelihood in such a hostile environment. Therefore, the identification of priority blocks in terms of the degree of vulnerability is very important for resilience building and disaster preparedness. In this context, the coastal vulnerability index (CVI) of ISD was assessed based on multi-criteria decision-making approaches (MCDA). Various vulnerability sub-indices like exposure, sensitivity and adaptation capacity index were calculated based on 22 indicators primarily considering physical, climatic and socio-economic variables. The CVI was constructed using both equal and unequal weightage methods. All variables were given equal importance in the simple average method whereas unequal weightage was assigned to the indicators depending on their relative importance with vulnerability applying the methods of analytical hierarchy process (AHP) and principal component analysis (PCA). Thereafter, the composite vulnerability ranking (CVR) was statistically quantified using vulnerability index derived by aforesaid three methods. In this study, the vulnerability index was calculated for different administrative units which are considered here as C.D. Blocks. The analysis revealed that the southern coastal C.D. Blocks of the ISD which have direct coastline with the Bay of Bengal are most vulnerable due to the potential impact of coastal hazards whereas northern C.D. Blocks are comparatively less vulnerable because of less exposure to coastal hazards, moderate sensitivity and high resilience to resist the adverse impact of hazards. This study will help to understand the comparative similarity and suitability of these three methods for assessing coastal vulnerability and this information could be used as a recommendation for other regions also.

地势低洼的印度桑达班三角洲（ISD）极易遭受多种沿海灾害和灾难的袭击。全球气候变化影响了自然灾害发生的频率和强度，并给沿海居民在这种不利环境中维持生计带来了额外负担。因此，根据脆弱性程度来确定优先级块对于恢复力建设和灾难准备非常重要。在这种情况下，ISD的沿海脆弱性指数（CVI）是根据多标准决策方法（MCDA）进行评估的。根据22个指标，主要考虑物理，气候和社会经济变量，计算了各种脆弱性子指数，如暴露度，敏感性和适应能力指数。CVI是使用相等和不相等的权重方法构造的。在简单平均法中，所有变量都被赋予相同的重要性，而根据指标的相对重要性，采用分析层次分析法（AHP）和主成分分析（PCA）的方法，对变量赋予了不同的权重。此后，使用通过上述三种方法得出的脆弱性指数，对复合脆弱性排名（CVR）进行统计量化。在本研究中，针对不同的管理单位计算了脆弱性指数，在这里将其视为CD块。分析表明，由于沿海灾害的潜在影响，与孟加拉湾有直接海岸线的ISD的南部沿海CD区块最为脆弱。相对而言，街区的脆弱性较小，原因是其较少受到沿海灾害的影响，中等敏感性和抵御灾害不利影响的高复原力。这项研究将有助于了解这三种评估沿海脆弱性的方法的相对相似性和适用性，该信息也可作为其他地区的建议。