Water Quality Assessment of Purulia District, West Bengal, India Under Changed Climate Scenario

Sea level rise, droughts and hydrological floods are the most discussed impacts of climate change. In addition to quantitative aspects, climate change is also affecting the surface water quality around us. Pearson correlation was used to determine the relationship between meteorological parameters such as temperature and precipitation with surface water quality parameters such as pH, total dissolved solids, biological oxygen demand (BOD), chemical oxygen demand (COD), phosphate, nitrate, sulphate and ammonia were studied. The study was carried out for a period of 10 years (2012–2022) in the Purulia district of West Bengal, India. The results indicated a negative temporal trend in annual rainfall and positive trend in the average annual temperature. Rainfall had a strong inverse correlation with COD (−0.90). The average annual temperature had a strong positive correlation with COD (0.83), phosphate (0.71), ammonia (0.71), while having very low correlation of the temperature of surface water (0.28). BOD was also observed to have relatively strong correlation with phosphate (0.81) and ammonia (0.78). COD, phosphate and ammonia were proposed as sensitive water quality metrics to track the effects of climate change.