What is the phenomenon of El Niño, and how it affects Latin America

Centuries ago fishermen of the northern coast of Peru noticed, close to Christmas, the appearance of superficial waters that were relatively warmer than normal. They called this phenomenon the El Niño current, in allusion to the arrival of Baby Jesus.

The phenomenon of El Niño and subsequently La Niña (The Boy, and The Girl), currently known as El Niño Oscilación Sur (ENOS) (El Niño Southern Oscillation), is a recurring hydro-meteorological event that appears in an irregular manner every 2 to 7 years. The ENOS is the interaction between superficial waters in the Tropical Pacific Ocean and the atmosphere, affecting the water balances in the surface and leading to extreme situations. In its warm phase it is known as El Niño, and in its cold phase as La Niña. El Niño also generates changes in the wind, pressure, and temperature patterns, and if its intensity is severe, it may impact the 5 continents. 

The electric sector in the region is exposed to the effects of this phenomenon and, consequently, it endangers the productive development of the countries. Following is a brief description of the main risks of the phenomenon of El Niño for the electric systems of the region. 

The deficit of rain leads to droughts, severely impacting the hydrologic basins. The most noticeable effect on the electric sectors of those countries is that the lack of water in the dams significantly affects their capacity to generate hydroelectricity, the main source of generation in Colombia, Brazil, and Venezuela. In addition, the high erosion levels and the lack of water, facilitate the generation of fires affecting large extensions of vegetation, mainly in places where the infrastructure for the generation, transmission, and distribution of electric energy are located.  

For example, in the Caribbean coast of Colombia there have been severe periods of droughts for over one year. However, it has not only impacted the low hydrology scenario. This situation produces increases in thermoelectric generation based on fossil fuels, which in turn pressures the prices of electricity, leading to an insufficiency in the logistic capacity to import and store enough fuel to address the people's electric and mobility needs.  

In the southern end of the South American subcontinent, El Niño produces an extreme increase in rain, resulting in a strong growth of the water levels. For example, the Parana River, one of the largest in Latin America, which has two of the most important dams, Yacyretá and Itaipú, doubled its average flow in 2015, affecting families and leading to a state of alert within the population.   

These rains represent a risk for the physical vulnerability of the infrastructure such as housing and highways by the river's banks. In addition, the degree of saturation of the ground (maximum capacity of the ground to absorb water) may lead to landslides, mud avalanches, electric discharges, wind bursts, floods in machine rooms, loss of transmission towers, distribution posts, and impact on substations, clogging of dams, and the need to alleviate the maximum avenues that could generate impacts on the near-by populations and the electric energy generation infrastructure. 

In general, it may be stated that the risks for countries affected by floods during the development of the event, is the destruction of the existing infrastructure, which represents a loss of investments. This reality creates great concern when taking into account that the ENOS is a recurring event.