It is an assessment tool which is used for calculating the vulnerability of a region of a place to climate change.

Recognition of climate change as a significant global environmental challenge is of recent origin. Studies on meteorological data throughout the world in the past century demonstrate that climate is seldom constant. As per WMO, climate change is a general term that encompasses all forms of climatic inconsistency regardless of their statistical nature (or physical causes) and this includes climatic discontinuity, climatic fluctuation (variation) and climatic trend. Climatic fluctuation would accommodate both climatic oscillation and climatic vacillation either with rhythm or with periodicity.

Whatever might be the nature of climate change that bound to occur in a region, the out come would be permanent displacement of normal human activity. Attributed reasons for climate change are obvious, but the main reason is accumulation of green house gases in the atmosphere. Because of population growth beyond a threshold level, there would be greater demand for food, water and energy. This competition would degrade the existing water resources, agriculture and forest cover which are very sensitive to climate change.

Vulnerability assessment of a region for this sector would provide an opportunity to develop a proactive agenda to meet the challenge from climate challenge. This vulnerability assessment to climate change employs varieties of methods and tools and these include expert judgement, empirical modelling, quantitative modelling, predictive modelling and use of GIS remote sensing and experimentation. As each of these tools has their own merits and demerits a good strategy would be using some of these in combination.

Scientists (T.N. Balasubramanian, A. Arivudai Nambi and Diya Paul) working at M.S. Swaminathan Research Foundation, Chennai on ‘Vulnerability assessment and Enhancing the Adaptive Capacity’ project under the Climate Change Program have developed a statistical tool to assess the existing vulnerability of a region to climate change in terms of the current level of degraded resources. A few carefully chosen indicators representing the physical, biological, social and socio-economic scenarios of the region are used for this purpose.

Based on the discussions with the in-house experts, 15 indicators that are sensitive to climate were chosen. Each indicator was assigned an optimum value based on the performance of that particular indicator at the National/State, mostly reflecting the average value of the indicator. The value below or above the chosen optimum mark signifies the level of sensitivity expressed in terms of severe vulnerability, moderate vulnerability and light vulnerability scales.

These 15 indicators are further sub classified in to three groups. First group (Group 1) consists of six indicators, viz; population density, forest cover, water resources / water bodies, rate of food production, area under irrigation and level of literacy which would have severe impact in a region on account of climate change. If the value of the each indicator of the group quantifies as severe (S) according to the assigned scale against each, 100 points/weight age/marks are awarded. Similarly, for moderate (M) and lesser (L) category, 50 and 25 points are awarded respectively. The second group (Group 2) consists of three indicators, viz; rate of population growth, ground water position and poverty per cent, which are considered to have lesser or moderate impact as a result of climate change as compared to the indicators grouped under the first category. For the indicators grouped in the second category, 75 points are assigned for severe vulnerability, and 38 points for moderate vulnerability and 19 points for lesser vulnerability category.

The third group (Group 3) consists of six indicators, viz; per capita income, income source, seasonal dry spell, pest and disease out break, land holding size and intensity of soil degradation, which are considered to be relatively less important in terms of their impacts resulting from climate change and in comparison with the chosen indicators under group 1 and 2. The severe vulnerability category in Group 3 carried 50 points, while moderate and lesser category carried 25 and 12.5 points respectively. Thus, the points awarded to each indicator, under the three groups based on values obtained from the collected data serves as the ‘Main Factor Effect’. Alternatively points assigned to severe, moderate and lower categories for the indicator given in the first, second and third group could also be derived by the experts based on the expected damage to the system. An interaction table for 2025 (15x15x9) interaction points is arrived at based on the assumptions elaborated already relating to interactions between main factors in Group 1 and Group 1,2,3; between Group 2 and Group 1,2 and 3; between Group 3 and Group 1,2 and 3 as nine combinations of s x s; s x m; s x l; m x s; m x m; m x l; l x s; l x m; l x l (s=severe, m=moderate, l=low). Based on the direct and outcomes resulting from interaction points, weightage obtained for a particular area, the vulnerability scale of a region/area could be arrived at. This could be classified as below:

Severe : 4101 points Moderate to severe : 1591 to 4100 points Moderate : 1590 points Low to moderate : 282 to 1589 points Low : < 282 points