Finally hope for Southern Africa seems to be here! After years and years of going through the El-Nino induced drought, the region is expected to receive normal to above normal rainfall for the 2020-21 cropping season, as per the latest report from the Global Agricultural Geo-monitoring Initiative (GEOGLAM).
GEOGLAM predicted greater chances of a La Nina, a weather pattern normally associated with wetter conditions.
According to this global outlook report, Southern Africa may receive more rainfall compared to the 2019-2020 farming season.
The GEOGLAM forecast, a Geneva-based satellite monitoring observation system, forecasted that: “El Nino-Southern Oscillation (ENSO) neutral conditions are likely to continue through summer 2020 ENSO and Indian Ocean Dipole (IOD) conditions are currently neutral and are expected to remain neutral through the northern hemisphere summer.
This is indeed great news for a region that has lost wild animals, people and crops to draught in the past years, but as hopeful as the situation might seem-there are important facts associated to the La Nina weather pattern that should be known.
- According to weather experts, La Nina is a coupled ocean-atmosphere phenomenon that is the colder counterpart of Elnino. The name Lanina originates from Spanish meaning “the girl”, analogous to Elnino meaning “the boy”.
- Global climate La Niña impacts tend to be opposite those of El Niño impacts. In the tropics, ocean temperature variations in La Niña also tend to be opposite those of El Niño. During a La Niña year, winter temperatures are warmer than normal in the Southeast and cooler than normal in the Northwest
- According to the National Geographic society (Nat-Geo), La Niña typically brings extreme weather to the same regions most affected by El Niño, where people’s coping capacities have already been eroded. La Niña causes opposite conditions to those associated with El Niño: areas now experiencing drought are likely to face flooding, and areas that have seen excessive rainfall are likely to experience drought.
- La Niña ordinarily lasts between 6 and 24 months. La Niña events have occurred for hundreds of years and occurred on a regular basis, during the early parts of both the 17 and 19th centuries. Since the start of the 20th century, La Niña events have been recorded in 1903-1904, 1906-07, 1909-1911, 1916-18, 1924-25, 1928-30, 1938-39, 1942-43, 1949–51, 1954–57, 1964-65, 1970–72, 1973–76, 1983–85, 1988–89, 1994–95, 1998–2001, 2005–06, 2007–08, 2008–09, 2010–12, 2016, 2017–18 as well as 2020.
WHAT ARE THE EFFECTS OF LANINA WEATHER PATTERNS?
Just like Elnino, LaNina has got its own effects
- Increased rainfall- LaNina events are associated with increased rainier-than-normal conditions.
- Catastrophic Floods- If history serves us well, Southern Africa might witness another version of sorrow in this coming season. LaNina events are also known to cause disastrous floods, for example following the strong LaNina in 2010, Queensland Australia experienced the worst floods ever. This is a clear indication of how devastating LaNina can be
- Drier than Normal Conditions- Studies from the National Geographic society indicates that LaNina is characterized by over normal pressure. This leads to reduced cloud formation and subsequently reduced rainfall in that particular region. However, this can be longer or shorter, depending on the severity LaNina.
- Severe Tropical Storms and Hurricanes- The strengthening of trade winds in La Nina events is associated with some of the incidences of serious typhoons, hurricanes and very cold weather in various parts of the world.