Melting glaciers are going to affect food security

Glaciers are melting due to climate change. Along with changing rainfall, this can have major effects on how farmers farm. Starting with the Himalayas: by the end of this century, half of the ice there may have melted. "The Himalayas are sometimes called the Third Pole: they store the largest amount of snow and ice after the North and South Poles," says Hester Biemans. She, along with Wouter Smolenaars (PhD) and Fulco Ludwig (Chair of Water Systems and Global Change) are doing research for WUR into the possible effects of changing in meltwater on agriculture in Asia. "About a dozen rivers originate in the Himalayas," she says. "The Ganges, the Indus, the Yangtze. Two billion people live around those rivers. Not much research is being done into the impact of melting glaciers 'down the river,' for the people who are so dependent on this water."

130 million farmers dependent on meltwater

The time when meltwater is expected is going to change. "If it gets warmer, the glaciers and snowpacks will melt earlier in the year. Or there may not be a peak at all if there is little to no snowfall. We see such things happening when we calculate different climate scenarios, even in case of more positive climate scenarios. Farmers will have to start taking that into account in their water use and cropping patterns."

Through these models, the scientists want to gain insight into how less water and changing peak discharge times affect agriculture and food production. "We estimate that 130 million farmers in Pakistan and India depend on meltwater. They mainly use that water to produce rice, cotton and sugarcane. If the meltwater flows down from the mountains earlier, they will have to extract more groundwater later in the year, unless they can better retain the meltwater. This is because the growing season in summer is very hot and dry until the Monsoon rains begin. Farmers in Pakistan already pump a lot of groundwater for growing rice, cotton and wheat, and the population there is growing rapidly. The groundwater is dropping deeper and deeper and the accessibility of groundwater is under pressure. The same thing is happening in northern India."

Water conservation or other forms of agriculture

In cooperation with local institutes, Biemans and her group are looking at ways to start anticipating. "This ranges from innovative measures to fairly extreme changes in agriculture," Biemans says. "The first thing that springs to mind is water storage, which includes water from Monsoon rains, by building reservoirs. Another option is water conservation. One approach for this is flattening the land so, when irrigation is used, the water spreads more effectively. Other options include innovative techniques to grow rice with less water, or to grow other crops." Rigorous choices may have to be made. "It may become difficult to maintain food production given the mounting water shortage. Pakistan could think about growing less cotton to leave more water for food. This scenario is already being looked at, obviously in coopeation with local institutions. One of our PhD students works partly at the Pakistan Agricultural Research Council. The solutions we want to calculate do not come out of the blue."

Biemans may want to expand her research to look at the importance of mountain ranges and glaciers for global food security. "This needs more attention. It's typically WUR to look at the whole system, and that's what we hope to do."

Considering water a scarce commodity in Europe

In Netherlands, we can also start to notice the effects of glacier melting, namely in the Alps. There too, the volume of Swiss glaciers has halved in the past eighty years, says Arjan Budding, programme leader Sustainable water at WUR. In addition to rain, the Rhine is fed by meltwater. "We see it happening right now: this year, there is very little snowfall in the Alps. If there is also very little rain later this year, it can become dry again in the summer. The glaciers have no accretion and the base runoff will be small. This could make us completely dependent on rainfall, and that is a concerning prospect."

Last summer, low water levels in the Rhine were mainly due to insufficient rainfall. The Rhine has an important transport function, and this has far-reaching consequences: in the eastern Netherlands, there was a fuel shortage because, due to low water levels, Shell could no longer use river transport to supply their tranfer station. In Europe, discussions must intensify on how to better retain and divide the scarce water, Budding says. "We are now working together in a Rhine consultation with Germany, France and Switzerland, but that is mainly about water quality and excessive water levels and peak discharge during crises. It is now also important to work together within the Rhine basin at low water levels, and to start talking about water distribution in the entire river basin. The Netherlands is a delta, and we are situated at the end of the river. Our interests are great, but we are also very dependent on our upstream neighbors."

Indeed, the Rhine is one of our largest freshwater suppliers, particularly in the western part of the country. "Fresh water is important for drinking water and agricultural land. If the Rhine does not supply enough fresh water, salinisation occurs as salt water creeps into the land. Farmers in the province of Zeeland already notice this; the water is sometimes too brackish to use." Water should be considered a scarce commodity, Budding says. "We also have to prepare for other forms of agriculture, or a different distribution. For example, grow less corn and more grain on the higher sandy soils. The latter is less sensitive to drought, so more water is left for other functions in the area, or downstream areas. What type of agriculture is suitable where? Water and soil must become guiding factors in spatial planning. This is also a promise in the coalition agreement from the Dutch government. As WUR, we are involved in translating this into concrete measures. In the Netherlands, we have focused on maximisation and production-optimisation-oriented agriculture, and that everything is possible; "make-able". That got us far - "God created the earth, but the Netherlands is made by the Dutch" (I often heard abroad) - but it now needs to be done differently; our focus needs to shift to more sustainable food systems, by making water a priority in our thinking."

Internationally, the geopolitical components of drought are also becoming apparent. "Turkey has built reservoirs in the Euphrates and Tigris rivers, which is resulting in less water in Iraq. The same goes for the Grand Ethiopian Renaissance Dam at the border between Sudan and Ethiopia and its impact on available quantities of Nile water in Egypt." Food for thought at the UN waterconference, to be held in New York, March 22-24.