NT NETWORK
Panaji
Inconsistency in light and moderate rainfall over the last 100 years has threatened water security in the state, a study has said, predicting thAat water security will deteriorate further under climate change scenarios.
The draft Goa state action plan on climate change 2020 of the Goa State Biodiversity Board prepared through NABARD Consultancy Services has said that there is an increasing trend in the inconsistency of daily rainfall activity due to an increase in the frequency of extreme events in the global warming era, resulting in depletion of light rainfall events that nourish life-forms and ecosystems.
The researchers investigated climate projections in Goa in the 21st century based on high resolution regional climate models, and have found that exceptionally very heavy extreme daily rainfall events of 150mm and 200mm rains, which are rare and exceptional in today’s climate, will become commonplace in climate change scenarios of Goa.
The draft plan, which has been kept open for public inputs and suggestions till December 10, has shown that the rise in the frequency of extreme rainfall events over the last century has not only threatened water security in the state, but also made it more vulnerable to flooding.
Although in the observed climatology over 1901-2018 the mean annual rainfall in the state has increased, but the researchers have said
that it has not helped the water security scenario in the state as the moderate to light rainfall events that nourish ecosystems have declined; and very heavy and exceptionally heavy rainfall events that cause devastation and chaos to life-forms and ecosystems have increased.
The rainfall anomaly (percentage departure from the 1960-1990 mean) for the period 1901-2015 shows that mean annual rainfall in Goa has consistently increased over the last 100 years which means the number of rainy days experiencing heavy rainfall has increased by about 60 per cent and extreme rainfalls (very heavy and exceptionally heavy) have increased by more than 100 per cent.
It has also been mentioned that mean annual rainfall in Goa has increased by about 68 per cent over the last century and in North Goa is found to have increased from 3000 mm in 1901 to 5000 mm to 2015 (an increase of 66 per cent).
The study has shown that under future climate projection scenarios very heavy and exceptionally heavy rainfall events are likely to increase further. Also, losses from ‘evapotranspiration’ due to warmer climate are projected to increase; water security scenario in the state is likely to deteriorate further under climate change scenarios.
To ensure availability and sustainable management of water, the plan set a target of 2030 to substantially increase water-use efficiency across all sectors by placing a system of suitable water pricing to deal with increasing water scarcity in the future.
