of vulnerability. But his team considered two additional factors – how long a flood wave lasts and how fast a flood wave rises. Fast-rising flood waves do not give people time to adapt or escape. The analysis shows that the flood peak stage – the maximum height to which floodwaters rise – and flood volume will increase in future. The spells of intense daily rainfall are also expected to increase. It is the pre-monsoon showers, rather than the monsoon, which will increase because of global warming. The scientists say that the duration of floods will decrease, but the height to which floodwaters rise will increase. This means that more areas will be inundated. Says Dulal Goswami, former professor of environmental science at the University of Guwahati who has been studying the Brahmaputra floods for years, “So far, we were receiving generalised, long- term information that could not be factored into specific local projects. We need short-term, focused information that can be factored into developmental processes; as well as for river and water resources management.” The findings have huge implications for poor and marginalised farmers in the Brahmaputra riverine area, as their main agricultural activity is in the pre- monsoon season. Many poor farmers take to the riverine area in October and begin to grow crops, till the rain-triggered floods begin. Then the farmers shift in country-made boats to higher areas and wait for the waters to recede. A second fallout of shorter-duration flood waves during a spell of heavy rainfall is that most water flows away, leaving little water for the catchment area.
Meanwhile, the International Centre for Integrated Mountain Development (ICIMOD) in Kathmandu is testing its community-based flood early warning system (FEWS) to help local communities cope with smaller- scale floods in the Brahmaputra. ICIMOD installed three FEWS along the Jiadhal and Singora rivers in the eastern Brahmaputra sub-basin in 2014, after conducting a risk, hazard and vulnerability assessment of the area. Plans are afoot to install them at the end of July this year too. Discussions on extending the system across other rivers in the Brahmaputra basin, prone to incessant flooding, are also on.
The downside, however, is that the small ICIMOD systems get washed away in massive floods. But, says ICIMOD expert Nand Kishor Agrawal, there are other systems for massive floods, and “quite often people have to deal with small floods more frequently than massive floods. In such situations FEWS prove much more beneficial.” Source: Padma, TV (2015) ‘Beware Assam.’ The Telegraph , Calcutta, India [online], 27 July 2015. http://www.telegraph india.com/1150727/jsp/knowhow/story_33765.jsp (accessed 16 October 2015)
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