Climate change in Chile: a national reality

08/04/2015

By Gianfranco Marcone Osorio, professor of agrometeorology and climatology. School of Natural Resources Duoc UC.

In recent years, Chile has been experiencing water deficits that already appear as permanent, as well as a change in the seasonality and distribution of rainfall, which cause phenomena such as the one that recently occurred in the north of the country.

Product of the drought, which has been dragging for several years, there are to March of this year 43 communes with decrees of water scarcity in force, between the regions of Atacama and Libertador Bernardo O'Higgins. This without considering the southern regions of our country, from La Araucanía to Los Lagos, which had the driest January of the last 55 years, according to the Chilean Meteorological Directorate, severely affecting agricultural activity in the area. This situation could be further aggravated if the rainfall this year does not reach at least normal levels.

With the water deficit on the one hand, the precipitations explode in places unthinkable by the other. This phenomenon, which occurred in the north, was due to the fact that the isotherm (height at which it begins to precipitate in the form of snow) was much higher than the historical average, therefore there was more precipitation in the form of water than snow, which drained quickly, dragging large amounts of soil, sediment and material accumulated by years of drought in the basins. Rescatable is the fact that some reservoirs have been filled, which is beneficial for having some water reserves.

This situation is particularly unusual and one-off, falling more than 20mm in 24 hours, in places where it falls less than 2mm in a full year. So much rain in such a short time does not benefit agriculture at all since there is no soil with the capacity to completely infiltrate that amount of water, causing the damage that we have seen in the press in recent days. Water, apart from being very necessary, needs to arrive with an adequate distribution during the year, a situation that has been changing dramatically in recent years.

The last year, at this same time, there was talk about the rather high probability that the El Niño phenomenon would arrive, which could come with intense characteristics, very similar to the one occurred in the 1998 year, when there were great floods in the area central of the country. What happened? As we talked about probabilities, those probabilities were decreasing with the passing of the months and the phenomenon never reached the 2014 year.

What's wrong with this 2015? The scenario is different, since now we are not talking about the probability of arrival of El Niño, but that this phenomenon is already installed in our country. Although it is of a weak nature, it should also cause a year within the normal ranges of rainfall, and could even be somewhat above normal. Does this help the drought? It probably does not solve the problem in the background, but it does allow it not to continue to escalate the problem.

Our country, before the scenario of Climate Change that we are living, is moving towards a desertification process in some northern areas, where the desert is expected to advance to regions such as Coquimbo and could even reach the Valparaíso region. For this reason, in some areas it is already experiencing the appearance of new species, which have lower water requirements and are adapted to drier climates, such as quinoa.

The water crisis is already a national reality, and although this year it is very likely that rainfall will be more abundant than in previous years, this crisis is here to stay. We are no longer talking about the climate change that will come, but about what we are experiencing now. The key at this moment is in the efficient and sustainable management of new technologies with respect to the use of water and in having new and better professionals and specialized technicians, who have the necessary skills for a good use of water resources and in the efficient management of irrigation systems.

Source: Fruit Portal