There is a “gap” in the global design that is not to be neglected, it is rather an earth-sized “hole” and it concerns the water and the global demand for food.
And this is because, in order to keep up with global food needs, the production of crops must increase by at least 50% until 2050. But even if we leave aside all the other problems, such as the effects of heat, soil degradation, plant diseases. plants, there is one which, without the help of any other cause, could prevent the nutrition of the world’s population: water.
A paper published in 2017 estimated that to match crop production with expected demand, irrigation water use would have to increase by 146% by mid-century. Here we have a little… problem: The water is already used up.
In general, dry parts of the world are becoming drier, partly due to reduced rainfall, partly due to reduced river flow as mountain ice and snow retreat, and partly due to rising temperatures causing increased evaporation and transpiration from plants.
The water needed to satisfy food is not available
Many of the world’s largest growing areas are now threatened by “flash droughts,” in which hot, dry weather saps moisture from the soil at an alarming rate. Some places, like the US Southwest, which is now in its 24th year of drought, may have moved into a permanent drought state.
Rivers are unable to reach the sea, lakes and watercourses are shrinking, freshwater species are disappearing at a rate approximately five times that of land-dwelling species, and major cities are threatened by extreme water stress.
In a planet plagued by warming and drought year after year, governments willingly ignore a looming crisis – that of water.
Already, agriculture accounts for 90% of global freshwater use. We pumped so much out of the ground, we changed the rotation of the Earth! The water needed to meet growing food simply isn’t there, experts say.
This 2017 article notes the British curator, should have given everyone an uneasy reaction. But as usual, it was ignored by policy makers and the media.
The case of Spain and the melting of the glaciers
Only when the problem reaches Europe do we recognize that there is a crisis. And while there is panic over the drought in Spain’s Catalonia and Andalusia, there is an almost complete failure among powerful interests to recognize that this is a single case of a global problem that should be at the top of the political agenda.
Although the drought measures have sparked protests in Spain, this is by no means the most dangerous flashpoint. The Indus River basin is divided by three nuclear powers – India, Pakistan and China – and several highly volatile and divided regions, already plagued by hunger and extreme poverty.
Today, 95% of the flow of the river during the dry season is extracted, mostly for irrigation. But water demand in Pakistan and India is increasing rapidly. Supply – boosted temporarily by melting glaciers in the Himalayas and the Hindu Kush (Indian Caucasus) – will soon peak and then decline.
Even under the most optimistic climate scenario, runoff from Asian glaciers is expected to peak by mid-century, and glacier mass will shrink by about 46% by 2100. Some analysts believe that competition for water between India and Pakistan is the main cause of the returning conflicts in Kashmir. But unless a new Indus waters treaty is struck, given dwindling reserves, these conflicts could be just the prelude to something much worse.
Measures to limit water consumption are not enough
There is a widespread belief that these problems can be solved simply by increasing the efficiency of irrigation: huge amounts of water are wasted in agriculture. And yet, there is a paradox in the effectiveness of irrigation. As better techniques ensure that less water is required to grow a given volume of crops, irrigation becomes cheaper.
As a result, it attracts more investment, encourages farmers to grow thirstier, more profitable plants, and expands over a larger area. This happened, for example, in the Guadiana river basin in Spain, where an investment of 600 million euros to reduce water use by improving irrigation efficiency increased it.
The paradox can be overcome by regulations: laws to limit both aggregate and individual water consumption. But governments prefer to rely only on technology. Without political and economic measures, however, it does not work.
Also, other technical means are unlikely to solve the problem. Governments are planning huge engineering projects to channel water from one place to another. But climate collapse and increasing demand risk drying up many of the water-bearing regions.
What can be done so that we do not call the water a little water?
Healthy aquatic ecosystems and improved water management can reduce emissions of greenhouse gases and provide protection against climate risks, the United Nations notes in its report “Water – at the center of the climate crisis”.
In addition, wetlands such as mangrove forests (a type of subtropical and tropical coastal forest dominated by salt-tolerant plants), seagrass meadows, swamps and marshes are very effective carbon sinks that absorb and store CO2, contributing to reducing greenhouse gases.
Wetlands also act as a buffer against extreme weather events. They provide a natural shield of storm protection and absorb excess water and rainfall. Through the plants and microorganisms they host, wetlands also ensure water storage and purification.
Early warning systems for floods, droughts and other water-related hazards provide more than a tenfold return on investment and can significantly reduce the risk of disasters: a 24-hour warning of an upcoming storm can reduce subsequent damage by 30%, as highlighted in an exhibition.
Suffice it to say that water and sanitation systems that can withstand climate change could save the lives of more than 360,000 babies every year.
Finally, climate-smart agriculture that uses drip irrigation (based on watering the plant/tree etc. rather than just irrigating the soil) and other means of more efficient water use can help reduce demand on fresh water reserves.