El Niño is a natural climate phenomenon marked by warmer-than-average sea surface temperatures in the central and eastern Pacific Ocean near the equator, which occurs on average every 2-7 years. The higher-than-average sea surface temperatures over the Pacific Ocean alter the normal rainfall patterns of various global regions due to the interaction between the oceans and the atmosphere.    Over East Africa, it is often but not always associated with heavy rains and floods during the OND (October-November-December) season; the phenomenon may cause the OND season to extend to January. Conversely, the phenomenon is associated with drier than usual conditions over some parts of the globe, such as Indonesia, Australia and southern parts of Africa.

It is important to note that El Niño itself is not rain but rather an effect that can affect weather patterns and lead to heavier-than-normal rainfall in East Africa. While heavy rains are commonly experienced during El Niño events, it is important to keep in mind that other factors can also contribute to heavy rainfall events over the region.

Where El Niño is often associated with heavier than normal rainfall, like in Kenya, businesses can mitigate against its impacts by climate-proofing their physical infrastructure. This can be done by reinforcing the physical infrastructure to withstand the flooding extent and levels caused by rainfall of the highest magnitude ever experienced over the location of the business.   Additionally, businesses must keep up with updates issued by the local agency (Kenya Meteorological Department for Kenya) mandated to issue weather and climate forecasts in order to take preventive measures that could minimise impacts before the onset of any expected heavy rainfall event.  Since there is always a level of uncertainty in even the best forecasts, businesses should practise other risk management practices, such as insuring their property.

Risk assessment for businesses can be achieved by evaluating the historical impacts of previous extreme events. Ideally, this should be done by determining the level of damage caused by rainfall of various magnitudes during past events and calculating the return periods of such events. The assessment can be enhanced further by considering the future chance of occurrence of more extreme events by taking into consideration climate change projections. This entails close collaboration between businesses and meteorological agencies to foster information sharing and good record-keeping of impacts by businesses. 

One way that businesses can better prepare for El-Niño and the safety of their employees is by subscribing to warnings and alerts by the local meteorological agency and creating digital infrastructure, such as ensuring access to the internet and to business servers that can enable the employees to work remotely in case of an extreme rainfall event.   This should also include a channel of fast communication with all employees for emergency alerting.

Heavy rainfall events can interrupt the supply chain of a business abruptly and adversely affect the business. This can be mitigated partially by subscribing to weather alerts from the meteorological agency to enable swift decision-making on possible early actions (e.g. change of route)   to forestall undesirable consequences. Other useful measures that can be taken include prepositioning adequate supplies, having backup power sources and investing in cold rooms for perishables as well as ensuring an efficient communication network along the chain.  

 Dr. David Gikungu, KMD & Ms. Mary Kilavi