January in North West Wisconsin? That's not cold, son. Back in my day.....
.....we lived on a snowball.
No, that's not really true. No one lived on a snowball.
But let me tell you a story.
Once upon a time, it was a dark and stormy night. Low pressure fronts kept coming in from where Canada would eventually be, and the jet stream shifted, drawing all the cold down to the south. The cold spell lasted for a long time. Tens of thousands of years, to be exact.
The cold caused more snow to fall in the north and south, near the poles. With a thicker snow pack, the temperatures didn't get as high in the warm months, which meant less snow melted. And colder winters meant more snow fell, which kept the summers cooler, which meant less snow melted, which kept the winters colder, which allowed more snow to fall, which kept it cooler which.....well, you get the idea.
It was the start of one of the many ice ages Earth has had.
As the years went by, the glaciers grew. And they expanded. And they kept expanding. And expanding. And expanding.
Something was terribly wrong. Always before, something called 'The Long Term Carbon Cycle', (that's a story for another day), would assert itself to fix the climate.
But, for whatever reason, this time, it didn't.
Well, the glaciers did eventually stop expanding. They had to. The ones from the north had met up with the ones from the south at the equator.
Earth was totally encased in ice.
Sounds like a good Hollywood disaster movie about what we're doing to the climate with all our pollution, right?
Unfortunately, this isn't a made up scenario. It has happened. A few times, actually.
It's a condition scientists call 'Snowball Earth'.
Some of you may remember me mentioning it in a previous post.
But, according to scientists, Snowball Earth is the greatest catastrophe to ever hit the planet. Some say it's even worse that the Thea Impact event. (again, story for another post).
It's most likely the closest life has ever become to be totally wiped out.
At the time of the last Snowball Earth, life consisted of mostly Cyanobacteria. You may remember them as the blue/green algae that spent billions of years filling the atmosphere with oxygen. They did this through photosynthesis. That's the process of eating a molecule of water, digesting the hydrogen and farting out the oxygen.
The conundrum science has is explaining how photosynthesis continued with a complete coverage of ice. You need sunlight to use photosynthesis. And, ice is opaque. Yes, some light can pass through thin layers of ice, but it's speculated that the ice at the equator was up to a mile thick.
The leading theory is that the planet wasn't 100% covered in ice. It's speculated there were hot spots caused by volcanic activity that kept small areas free of ice. This allowed life to go on.
After awhile, volcanic out gassing started melting holes in the ice. And these out gassings released copious amounts of carbon dioxide that had been trapped under the ice.
Fairly quickly, with in just a few thousand years, the ice receded.
In fact, it receded all the way. The carbon released caused hyper warming that would make todays climate change seem unnoticeable.
The last time we emerged from a Snowball Earth? About 600 million years ago.
As some of you will recall, that coincided with the phenomenon known as 'The Cambrian Explosion' about 560 million years ago. It's speculated that the sudden change from extreme cold to extreme heat, then climate moderation in, (relatively), quick succession, is what led to the sudden expansion of life from basic bacterial life to complex life.
So, keep in mind, while humans do affect the climate, and we should minimize our impact as much as we can, the planet is going to do what it wants to do.
And stop whining when there's a thin layer of frost on your windshield. It could be a mile thick sheet of ice.