Laut dem Geophysiker Klaus-Peter Knupp verschlechtern sich die Regenaussichten.
ENSO News
Yesterday’s (12th of September) El Nino Southern Oscillation forecasts (pages 6-8) show:
a. A weak La Nina is still in place at the moment, but rapidly disappearing from December onwards and heading into neutral territory and beyond by about May 2023. All by its own, this would translate into a wetter ‘small’ rainy season (Oct – Dec), but a normal-to-drier main rainy season (Jan – May). Note though that the ‘small’ rainy season is itself very unpredictable and can sometimes fail altogether (more below).
Today’s (13th of September) Indian Ocean Dipole forecast (page 9) shows:
b. That currently the IOD is strongly negative and recovering to neutral by February. So the IOD is not supportive of rain until at least February.
Added together, the negative IOD is likely to put a damper on the ‘small’ rainy season (which might fail as a result), while the dissipating La Nina puts a damper on the main rainy season, even though we are fortunately not quite moving into El Nino territory as yet. Overall my estimate would be an average to below-average 2022-2023 rainy season for Namibia.
Lets count ourselves fortunate tough that we have been spared a true El Nino now for three rainy seasons in a row (the last El Nino being 2018 -2019). An El Nino event releases enormous amounts of heat into the atmosphere and brought us both heat and drought in the 2018-2019 season. Given that the last three La Nina’s have given us relatively cool and wet summers, we need to both mentally and physically prepare for the next El Nino, when it decides to come. Climate change is likely to exacerbate the heat we must prepare for in this event.
