Good news for the Andes, not so much for southern Africa. She’s back. La Nia has developed for the second consecutive year and is expected to last into early 2022.
"According to the National Geographic society (Nat-Geo), La Nia typically brings extreme weather to the same regions most affected by El Nio, where people’s coping capacities have already been eroded. La Nia causes opposite conditions to those associated with El Nio: areas now experiencing drought are likely to face flooding, and areas that have seen excessive rainfall are likely to experience drought.
La Nia ordinarily lasts between 6 and 24 months. La Nia 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 Nia 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.
La Nina Weather Patterns: What Southern Africa Should Know (farmingportal.co.za)
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