Yes, there can be no doubt that this planet of ours has gone through numerous cycles of extreme cold, with expanding glacial flows, and then followed by warmer climes with receding glacial flows etc.. etc..
The evidence is there for all to see. Striations in rock surfaces, valleys carved out, "preserved" forests uncovered, etc..
We've also, apparently, had this planet hit by large bodies from outer space which very likely caused enormous upheavals of physical debris which could also have affected the climate of that time.
So it seems that down the ages, be that hundreds, thousands, or hundreds of thousands of years, the climates, the oceans, the troposphere, the stratosphere have had their changes from diverse sources and influences. Cycles of one form or another came and went.
Now the question is .... in recent times there have been influences entering the system that were not there prior to the enormous amount of industrial activity that has taken place in the last 100 years or so. That activity has been increasing, it seems to me, at an exponential rate.
We, as a species, have been adding stuff to our environment at an enormous rate. And isn't much of that stuff unique in terms of the fact that it wasn't being added before ?
But that DOESN'T NECESSARILY MEAN that any "warming" or "cooling" or "deficiency" in food chains or plant life is being caused, SOLELY, by our actions.
Those causes can, to a large or whatever extent, still be caused by the very factors that you've mentioned in several of your posts. The retreat of glaciers may still be caused, to a large extent, by those factors that caused them to retreat millennia ago. But is it not possible that what we are adding or subtracting to our environment is also, to some degree or other, contributing to that retreat ?
And is it also not possible that the decrease in Phytoplankton content in our oceans is possibly also being adversely affected by what has been introduced into our environment in the last 80 to 100 years, apart from what you stated in your post ?
So maybe it's a case, as I alluded to in my previous post, that what is happening in our environment is a combination of natural occurrences PLUS what is coming about due to what has been added as a result of our exponentially increasing industrial outputs. |
