Ene Ben Noll zegt er dit over.
Sudden Stratospheric Warming (SSW) events, as they're called, are predictable weeks to months in advance, but we don't often get a signal seasons out. Well, in 2021-22, we are getting a signal and it's a pretty strong one! This is helpful with winter climate predictability.
In 28 years of seasonal ECMWF guidance issued in September, there was a signal (≥1&sigma
for an SSW in 4 Decembers before this year. An SSW happened in 3 out of 4 of those winters, but there were misses in the early 2000s. The signal in 2021-22 is the 2nd strongest of all cases
for an SSW in 4 Decembers before this year. An SSW happened in 3 out of 4 of those winters, but there were misses in the early 2000s. The signal in 2021-22 is the 2nd strongest of all cases 
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