In the recent controversy over the retreat of Himalayan glaciers in which the UN's climate science body acquiesced that it was an error to assert that they would disappear by 2035, in fact now water availability has emerged as a key issue with even more uncertainty.
The Himalayan glaciers grabbed immediate headlines as they feed the major rivers in South Asia and some parts of Southeast Asia, which is home to a worth proportion of the planet's population.
The question surrounding the big minds is that if the glaciers significantly retreated or if they disappeared, it would be a calamity and an issue of life and death for many millions of people who depend on these rivers.
But now that the Intergovernmental Panel on Climate Change (IPCC) has just said that it was a mistake to say the glaciers will be gone in a matter of decades, does that really mean that water is not a worrying issue any more?
Majority of the scientists believe it is - even more so more given the uncertainty surrounding the future impacts of climate change in a region of not only high population, but one of high population growth also.
The broader consensus is that the glaciers themselves are indeed retreating, although the rate of the recession can be treated as debatable.
However, not forgetting that there are other climate-influenced factors that affect river flows, such as changes in precipitation, snowfall and regional temperature.
Uncertainty of Time
Mats Eriksson, a senior hydrologist with Nepal-based International Centre for Integrated Mountain Development (ICIMOD) says that there has been too much focus on glaciers whereas there are other factors like precipitation and snowfall that affects the levels of waters in rivers downstream the eastern Himalayas, Just below the eastern part of the Himalayas are flowing the major rivers like the Ganges and the Bramhaputra, as well as their tributaries.
And these are the vital lifelines for millions of people in India, Bangladesh, Nepal, Bhutan and Tibet.
World Bank's recent study has shown that the volume of water resulting from glacial melt in Nepal makes up less than 5% of the flows of rivers leaving the country and contributing to the Ganges downstream.
"That means, about 95% or more of the river flow is the result of rain and melting seasonal snow," said report co-author Richard Armstrong, a glaciologist from the University of Colorado at Boulder in the US.
If that is considered to be genuine, then rivers downstream of the eastern Himalayas will hardly be affected, even if the glaciers recede or disappear.
However, the question is whether the other contributing factors to the rivers' flow, like precipitation and snowfall, remain the same in the changing era of climate?
NO, quotes the scientists, but nobody knows that whether that will lead to rise or fall of rivers' levels - and by how much it will and when - are the questions still waiting to be answered.
It is quite agreeable with Dr Eriksson saying "We are seeing some changes in the monsoon".
"For example Last year, the monsoon arrived one full month late in Nepal and then some places saw 80mm of water in a day during the delayed rainy season.
"But the problem is that there has been no consistent measurement of precipitation and temperature and there is a huge lack of proper studies."
Are these flows Rising or falling ?
Some of the scientists say increasing temperature has meant that glaciers don't get enough snowfall during winter and therefore river flow during summer is dwindling.
Professor Mohammad Sultan Bhat of Kashmir University says"We have seen the decline in the flow of the Indus, Chenab and Jhelum rivers".
"We have recorded a decrease of 40% in the flow of Jhelum's tributary river… that is fed by the receding Kolahi glacier."
With the glaciers offering such complex pictures and attributes, combined with precipitation and temperature patterns becoming more and more complicated, the region's river systems that depend on all these factors cannot be simpler.
Politics and geography, experts say, have made understanding the situation even more difficult.
"Some countries in the region are not willing to share water-related data because they regard it as confidential," said Dr Eriksson of ICIMOD.
Since it is really difficult to access them, so proper studies on water availability still remain a major challenge.
Source: BBC News
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