Climate Change

Data collected and analysed by the India Meteorological department for Assam for the period 1951 to 2010 across 6 Stations for temperature and 12 Stations for rainfall, indicates that the mean temperature in the State has increased by +0.01oC/year, with an increase in seasonal temperatures across seasons with pronounced warming in post monsoon and winter temperatures. The annual rainfall has also decreased by -2.96 mm/years during the same period. The southern part of Nagaon district in central Assam valley and adjoining parts of Karbi Anglong form a rain-shadow zone where annual rainfall is as low as 800-1200 mm. Rainfall in this zone is decreasing slowly as found in Lumding where rainfall is on the decline at a rate of 2.15 mm per year .
District level climate projections for the period 2021–2050 for Assam indicate rising temperature trend which may increase by 1.7-2.0oC wrt to base line. Only the western part of the State will experience slight decrease in rainfall but the rest of Assam is projected to have increase in rainfall. There is likely to be increase in extreme rain fall event by 5 to 38% wrt to base line. Droughts weeks are going to rise, with Southern districts showing marginal reduction in drought weeks but rest of the district show an increase by more than 75% wrt BL. As regards floods, they are going to rise by more than 25% in the southern parts of Assam.
As Assam becomes warmer, the change in weather pattern will effect the state’s flora and fauna, where species that are less adaptable, may perish, affecting the state’s overall environment wealth. Moreover, communities who depend on certain species will also be affected, as they will need to change their traditional patterns of living. For example, due to impact of climate change, farmers are moving to different local rice varieties, like ahu dhan and bao dhan instead of adhering to certain varieties of rice like khali dhan which are traditionally eaten during the monsoon season. Climate change is spreading the growth of weeds like Parthenium, causing the disappearance of local vegetables like kola kosu, dhekia xaak, maimuni etc and increasing bronchial and skin allergy. Spurt of invasive weeds like Dicanthium, which is also resistant to weedicide, is causing a havoc in the tea sector, cornerstone of the state’s economy. Seasonal vegetables are losing their taste and popular indigenous rice varieties are witnessing a drop in grain quality.