The La Nina test (and perhaps in the broader sense the solar minimum) may well have passed a ‘relatively short term’ test when it comes to global temperature over the last 12 months…

Here’s the 1st of 2 excerpts from my 2020-21 winter forecast issued early December 2020

Big test coming up

La Nina

As seen in the below SSTA chart, the current and already mature La Nina stands out.

The most important aspect to the La Nina is that this SHOULD have a cooling influence globally. However, that cool down appears to be delayed, perhaps denied by continued warmth in several if not many areas of the world. I can only hope that this La Nina has the ability to turn down earth’s climatic thermostat.

Then

Now

Difference in past 12 months.

North Atlantic

The atmosphere has indeed responded GLOBALLY to the ‘cooler ocean’. My understanding is this, El Nino’s release vast amounts of water vapor from ocean to atmosphere which traps in heat and lifts the global temperature. The opposite occurs with a La Nina. Less water vapor allows more heat release from atmosphere to space.

The below graphic shows the fall in temperature in response to both La Nina and cooling SST’s elsewhere.

February wound up 0.01C above normal globally for the 1991-2020 period. Coolest February for the planet since at least 2014.

Solar

Excerpt from winter forecast 2020-21

“When looking back to the end of the 21st century’s first decade, we ended cycle 23 and began cycle 24. Prior to the most recent solar minimum, the last occurred in 2008 and was followed, coincidentally or not, by the worst back to back spells of winter for the UK and Western Europe since 1978-79.

The big test comes either this winter or even more so next, whether the weaker solar cycles of modern times really do provide cooling influence on our climate the way some in the scientific community believe. I truly believed that the 2009-10 and first part of 2010-11 happened as a direct consequence to the solar minimum. But that being said, despite have supposedly the weakest sun in 200 years, why is our planet continuing to warm.

We are back to the same solar state/cycle/minimum as we close 2020 as we were in December 2009. Let’s see what this winter brings as solar minimums are meant to increase -AO/NAO’s, SSWE’s and harsher winters. We observed a record -AO/NAO during winter 2009-10. Solar minimum induced? If so, you’d expect another strong -AO/NAO this year or next.”

Result

So, winter 2020-21 DID indeed produce a firmly -AO and to a slightly lesser extent, NAO winter with a weak polar vortex and occurrence of an SSWE.

The counterbalance was of course the La Nina and while this has a global cooling effect, can provide quite the opposite type of winter for the UK and Western Europe as well as the Eastern US and Canada.

I believe we ‘may’ have actually seen a far worse winter in 2020-21 had the ENSO been neutral or positive. That being said, the solar minimum and it’s lag effect should in essence live on for perhaps the next couple of winters.

So, earth has cooled and though by no means a blockbuster, we did witness extreme winter weather in many areas of the Northern Hemisphere.

Despite record warmth during the 2nd half of February, the month of February wound up below average throughout Northern Eurasia and much of North America and about average Globally.

Interestingly many Northern land areas of the hemisphere not only recorded a cold February but recorded a colder-than-normal winter.

Following one of it’s hottest summer’s in 2020, Siberia was treated to one of it’s coldest winters in decades.

It’s of no coincidence that the US observed it’s coldest February since 1989.

The ‘big test’ this past winter came twofold. The 1st being a noticeable downturn in global temperature with the present La Nina, 2nd was the solar influence as we come off a new minimum in the midst of the quiest/weakest sun in 200 years. The question being, do we see a negative AO/NAO winter either producing a period of extreme cold or something resembling the long winters of 2000-01 and 2009-10 (the cold which followed the previous two solar minimums.

What Next?

While earth isn’t AS warm as it was in 2020, there’s nothing to state a new ice age is upon us. After all, the La Nina will eventually fade and another solar maximum will come along helping push earth’s temperature back up.

However, the question I ask is this, how significant is the current cooling? Is it a mere blip, what kind of summer can we expect as the ENSO heads neutral. Will SSTA’s remain leveled off or will they warm back to levels in the wake of the previous El Nino and last 12 months? I don’t care which side of the argument you’re on but these are questions no-one can truly answer. Only time will.

According to various model projections, the La Nina essentially fades during the 2021 summer but could make a return in the autumn and possibly next winter. That would be very interesting because that would mean we have a near 3-year La Nina and could support a ‘lingering’ pause or possibly fall in global temperature again.

The upcoming Northern Hemisphere summer is going to be most interesting to see what way the global temperature will go.

Tags: global temperature, La Nina, sea surface temperature, solar cycle, solar minimum, SST