How prepared are water and agricultural sectors in Sri Lanka for climate change?: a review

Climate is changing world wide, and the science community in Sri Lanka have come up with ample evidence to suggest that the country\u2019s climate has already changed. During 1961- 1990 it\u2019s mean air temperature has increased by 0.016 0C per year (higher than the global average of 0.013 0C), and mean annual rainfall- decreased by 144 mm (7%) compared to the period 1931-1960. In addition, mean annual daytime maximum and mean annual night-time minimum air temperatures increased. However, the bigger question of national importance is what Sri Lanka\u2019s climate will look like in 50 or 100 years and how prepared is the country to face it. Apart from the IPCC projections at the coarse global scale, few studies attempted to project future climate scenarios for Sri Lanka and to identify climate change impacts on agriculture, water resources, the sea level, the plantation sector, the economy and health. Vulnerability and adaptation to climate change are the least studied areas. The paper reviews the status of climate change research/activities in Sri Lanka with respect to future climate predictions, impacts, mitigation and adaptation, and identifies existing knowledge gaps. Messages emerging from this review suggest that Sri Lanka\u2019s mean temperature during the North-East (December-February) and South-West (May-September) monsoon seasons will increase by about 2.9 0C and 2.5 0C respectively, over the baseline (1961-1990), by the year 2100 with accompanying changes in the quantity and spatial distribution of rainfall. Extreme climate events are expected to increase in frequency. These changes will bring about widespread impacts on the country\u2019s agriculture and economy. For example, a 0.5 0C increase in temperature can reduce rice yield by approximately 5.9%; extended dry spells and excessive cloudiness during the wet season can reduce coconut yield so that annual losses can range between $32 and $73 million. Pilot studies in the Galle District suggest that sea level rise could inundate about 20% of the land area of coastal district secretariat divisions. Adaptation measures already undertaken in the agricultural sector include development of low water consuming rice varieties and use of micro-irrigation technologies. Tools have been developed for predicting seasonal water availability within the Mahaweli Scheme and for predicting annual national coconut production. However, Sri Lanka is yet to undertake a comprehensive national study on the vulnerability of its water resources and agriculture to climate change. Formulation of detailed and reliable future climate scenarios for the country is and urgent need in this regard.