The frontal system we faced yesterday brings new hope in the midst of the desertification process our country has been facing for 15 years. Were the rains a solution or simply an illusion of normality? Uncertainty persists, so it is important to carefully examine this phenomenon in the context of climate change to understand the measures we must adopt to effectively confront it.
Rain is, without a doubt, a precious commodity in a country affected by water scarcity. Its arrival offers a respite from a critical situation, especially in central-northern regions and provinces such as Elqui, Limarí or Choapa, which have been dramatically affected by the lack of water. However, it is important to bear in mind that the intensity, duration and distribution of these rains are determining factors, in addition to the fact that the isotherm 0 remains low (elevation 1000) to avoid negative effects, such as floods or landslides.
It is not certain that the recent rains will be able to alleviate the water deficit, and although every drop that falls from the sky is welcome, we cannot continue to depend on them to guarantee the supply of water to cities and productive activities as important to our economy as mining and agriculture. We need a winter with “normal” and homogeneous rains, accompanied by an accumulation of snow in the mountains to ensure an effective recharge of our water resources in the ecosystems and also in the reservoirs.
To illustrate this, in Santiago the climatological period between 1991 and 2020 had an average of 285 mm accumulated per year, a sum lower than the previous climatological value 1981-2010 which was 342 mm, and in these last 15 years of megadrought, where the average is 188 mm. If this year it could accumulate in the central zone of the order of 250 to 300 mm, it could be a good year that benefits the accumulation of water.
The expected amount of rain is crucial to determine its impact on the drought. Water is essential for all our activities, from food to agricultural and industrial production. If this rainfall is insufficient and the deficit continues for a couple of years, the situation could be dramatic. Thousands of people could face water rationing and be forced to migrate to wetter areas in search of subsistence.
Among the measures that must be adopted to take advantage of the rains are the restoration and conservation of our water ecosystems, the efficient use of agricultural irrigation, the reuse of urban wastewater and the development of rainwater harvesting systems. In addition, seawater desalination is emerging as a complementary solution that could diversify our water sources and increase our resilience to drought. Indeed, we already see how in the Antofagasta region, where rainfall has historically been practically zero and contributes little to the usual way of subsistence, today, thanks to desalination technology, water consumption for the population is guaranteed, regardless of weather conditions. We need a comprehensive approach that combines efficient water management, ecosystem conservation and the development of innovative technologies. Only in this way can we guarantee long-term water security and build a sustainable future for all.
