The upcoming "modern solar minimum"

[Turtlesteve]

I watched a presentation on climate and the upcoming solar minimum.  The short summary is that we're headed for a ~30+ year period of reduced solar activity starting in 2020.  The IPCC / global warming consensus tends to discount the impact, but the presenter believes that solar forcing has been underestimated, and we'll see severely colder temperatures in the next couple decades, potentially leading to crop failures and famine.

(2nd link is the presentation which is quite long but interesting)

https://www.livescience.com/61716-sun-cooling-global-warming.html

https://www.youtube.com/watch?v=M_yqIj38UmY

This certainly wouldn't fit with my long term gardening plans.

Steve

[Ed in Houston]

We had the coldest temps in 28 years at my place this past January. It sleeted a few days ago in Houston this which was the earliest ever recorded  for such an event in a winter season. Sunspots are getting sparser as they were during the Little Ice age.

 

The sun is always "acting up". Most have probably heard of variable stars that change in radiation emitted (heat) by a factor of 2-3 times in a few months. There are no completely stable stars but many like our sun are very stable and only change a few percent in heat out put over decades or millennia. Solar spots correlate to these cycles and are an indication solar heat. There are many cycles upon cycles the most frequent is the minor 11 year cycle. The there are much longer orbital parameters called the Milankovitch cycles which are long period and affect the heat reaching the Earth.

 

 

Currently we are in an inter glacial period within the ice age that began a few million years ago. Since entering the ice age  there have been about 20 inter-glacial warm periods that last about 10-15 thousand years and we are currently in one of these warm periods. These have huge temperature changes on the order of 10C degrees. Remember that the the polar ice caps extended south to St. Louis during the last glacial period ending 20 thousand years ago. We are about due to enter another Ice Age cold period again which would be a total disaster for civilization.

 

 

 

 

On a much shorter time span of hundreds of years the sun's radiation varies and sun spots are a reflection of the solar flux output. We entered the Maunder sunspot minimum and the the Dalton minimum a few hundred years ago and were in what was called the Little Ice age. During the Dalton minimum, the Mississippi river froze over at New Orleans and was spewing ice bergs into the Gulf off Mexico. There were also "frost fairs" on the Thames river during the Little Ice Age.

 

 

 

 

Some solar physicists have recently built models of the suns magnetic dynamos and are predicting another sunspot minimum coming in the next few years which if true would take our changing climate back to the temperatures of the Little Ice Age. Their hypothesis predicts that this will be apparent in temperatures realized by the year 2021 and the cooler temperatures will last for decades. If this hypothesis is true, the current subtropical climate of the Gulf Coast will be temperate and cities like Houston and New Orleans will regularly see 10F during the winters, sometimes colder, with yearly snow falls in Miami.

 

 

 

These short term variations above are minor compared to longer cycles of the ice age that we have been in for about 2-3 million years.  The ice age is bimodal having two conditions of stability. The Ice age conditions last about 125,000 years followed by a 10-15 thousand year warm period that we are at least 10,000 years into now. Then the cycle repeats again as it has for about 20 cycles so far. The warm interglacial period of the ice age that we are currently enjoying last about 10-15k years.

 

As you can see we have not yet reached the temperature that triggers the bimodal flip that takes us back to the deep Ice Age mode. We still have to warm about another 5 degrees F before the flip to the Ice Age occurs once again. The flip back to the Ice Age mode will occur regardless of Human's C02 emissions as the cycle has been established long before Human CO2 emissions. It is possible that Human C02 emissions will make returning to Ice Age conditions happen sooner as it is global warming that triggers the Ice Age!

 

Here is how the Ice Age has been triggered for the last couple of million years. The first indication that the flip to the Ice Age is about to occur is an ice free Arctic which we seem to be headed toward. An ice free Arctic adds an additional warming factor due to solar reflection/absorption parameter of ice versus water. This causes the Greenland ice sheet melting releasing huge amounts fresh water into the Atlantic ocean changing it's temperature and salinity and shutting down the Atlantic meridional overturning circulation.

 

"Atlantic overturning is not a static feature of global circulation, but rather a sensitive function of temperature and salinity distributions as well as atmospheric forcings. Paleoceanographic reconstructions of AMOC vigour and configuration have revealed significant variations over geologic time complementing variation observed on shorter scales. An AMOC shutdown would be fuelled by two positive feedbacks, the accumulation of both freshwater and heat in areas on downwelling".

 

 

Once the salinity of the Atlantic ocean is decreased sufficiently the Arctic circulation shuts down halting the warming of the Arctic and once again triggering the Ice Age mode. Historical data proxies indicate that Greenland melting occurs once the Arctic is ice free and about half of the Greenland ice sheet melts. This occurs when the temps are about 5 degrees F warmer that today. Sea levels in the past when the flip occurred were about 30 feet higher than today. Sea levels are already about 360 feet higher than at the end of the last ice cycle 20k years ago so we are almost there already with only 30 feet left to go. The fresh water ice melt dumping into the Atlantic and reducing the Atlantic salinity shuts down the Atlantic circulation. This cycle has been going on for a couple of million years and will happen again soon (hundreds to a few thousand years) even if Humans have zero C02 emissions as in the past.

 

One can expect the Arctic ice sheets to extend down the the central U.S once again. I am not worried in the least about how this will impact Human existence as in a few hundred years the progeny of Humans today will be so changed due to the evolution of AI/robotics, it will all be irrelevant.

 

Ed in Houston

 

 

 

 

 

[Matthew92]

The Showdown Begins in 2020

(excerpt) "A periodic solar event called a "grand minimum" could overtake the sun perhaps as soon as 2020 and lasting through 2070...

  The last grand-minimum event — a disruption of the sun's 11-year cycle of variable sunspot activity — happened in the mid-17th century. Known as the Maunder Minimum, it occurred between 1645 and 1715, during a longer span of time when parts of the world became so cold that the period was called the Little Ice Age, which lasted from about 1300 to 1850."

 

 

[sonoranfans]

Nice post Ed, the larger discussion on global thermals is rarely discussed in public.  I have read much of this before and as a scientist it puts a huge cloud over this chaotic system.  I guess public consumption is bite sized tweet science.  

[Funkthulhu]

And yet. . . .    Our anthropogenic carbon emissions have completely unbalanced these very subtle and delicate changes.  

There will be no new ice age.  Temperatures will continue to rise through 2020 and into the next century.

[mdsonofthesouth]

Considering we have seen earlier and earlier frosts and now snow in November! I have seen light flurries on thanksgiving ONCE in my life but never 3 inches of snow in mid November! We have the past few years seen colder and colder winters that seem to last longer each year, as well as false summers when May sees a chill to March or April temps. We are at January DEAD of winter temps for the foreseeable forecast and not even to thanksgiving. Snow near Houston before us and lets not discuss the 2018 event where we spent something like 250 hours bellow freezing with all time lows we haven't seen in decades. We have also seen Indian summer events and more days over 90F than ever, but also cool spells in September and as stated may.

 

So I could for sure see this hypothesis as possible. But NASA says it's part of an 11 year cycle and isnt as bad as yearly snow in Miami.

 

https://www.giss.nasa.gov/research/briefs/rind_03/

 

https://science.nasa.gov/science-news/news-articles/solar-minimum-is-coming

Edited November 16, 2018 by mdsonofthesouth

[Chester B]

On the west coast its the opposite.  Hotter and much drier.  Older homes here don't have AC as it was rarely needed, but things have changed.