One of the strongest El Ninos on record ended in May. A strong La Nina would normally follow. But that isn’t a sure bet this time around.
Brian Brettschneider is a climatologist in Anchorage who closely tracks Alaska climate data and trends. Alaska’s Energy Desk is checking in with him regularly as part of a new segment- Ask a Climatologist.
He says both El Nino and La Nina can have a significant impact on winter temperatures in Alaska, but if this La Nina materializes it may be a different story.
Brian: We’ve just come out of one of the strongest El Nino’s on record and that’s officially been declared over. And that’s reflected by sea surface temperatures in the central tropical pacific. Those are now below normal. If they stay below normal for an extended period of time we would then call that La Nina. There’s currently a 60% chance, is the latest forecast, that we would enter into an official La Nina.
Annie: What does it mean to be in a La Nina for Alaska?
Brian: If there’s a strong La Nina, Alaska typically experiences cooler temperatures, cooler with respect to normal. If there’s a weak La Nina, that relationship is much less pronounced. But if it is a weak La Nina, we might expect cooler temperatures but there’s so much warmth stored in the NOrth Pacific ocean it’s going to be really hard to dissipate that warmth, so I’d be surprised if we had a cooler than normal winter.
Annie: What would your guess be (for winter)?
Brian: I’ll defer to official guesses and those official guesses call for a warmer than normal winter- perhaps not record breaking warm, but certainly warmer than we would expect looking at the previous 30 years.
Annie: So some snow?
Brian: Snow is a different beast entirely. The precipitation patterns are much less correlated to the ocean state. So it can be really hit or miss. You know, last winter, as little snow as there was, it was actually quite a wet winter. And there were avalanches and fatalities and record snow in some spots in the mountains, but not so much down at sea level.