Is the Earth warming? Sure. Well, I guess it would be more accurate to say “probably” as we are talking about probabilities. We are, after all, still emerging from the last ice age. Just using the past as a guide, the Earth should get gradually warmer until it peaks in about 40 thousand years. At that time, it should turn around and head into the next ice age.
This, of course, ignores any catastrophic events which could impact this timetable, such as the super-volcano at Yellowstone blowing or an asteroid strike from space.
One thing we don’t have to worry about is CO2 levels. History shows no significant correlation between CO2 and temperature levels. They happily make wide swings up and down quite independent of each other. This is actually to be expected. While CO2 is a greenhouse gas, at about 1% of the total greenhouse effect, its contribution is trivial.
These are rather mundane, boring facts (except for the catastrophic events which can be fairly scary if you dwell too much on them).
But, all in all, we are at a pretty good place in Earth’s environmental history. We are much better situated being 15 thousand years after the last ice age than 15 thousand years before the peak of the next ice age. Life thrives during the inter-ice age warming periods as it much prefers warmth over cold.
Stories such as this [Carbon pollution] try to scare us. It does so by any number of underhanded ways. Let’s explore a few.
First, it warns us that “humans are re-creating the conditions that led to the worst-ever extinction” of marine life, the Permian-Triassic Boundary extinction. We humans are doing this “by combining oxygen loss with ever-worsening ocean warming and acidification…” There is a link provided to a story [Greatest Extinction] about this event. Please click the link and read the cited story.
There you will find that the environment, particularly the oceans, had already been placed “under pressure” due to a drop in oxygen levels and increase in temperature. The cited story [Greatest Extinction] doesn’t discuss what caused these conditions, but we can find out very easily that is was not because of high CO2 levels. At this time, and starting millions of years earlier, the CO2 levels were at historic lows.
Whatever the cause, the environment had already been stressed for many thousands of years. Then volcanoes started releasing vast amounts of CO2. How much? According to the cited story, it “was probably greater than today’s fossil fuel reserves.”
Meaning that if we dug out all the oil, coal, natural gas and peat moss available to us today and burned every last ounce of it, we couldn’t release that much carbon.
The shock to the already stressed environment was too much. Over the next 60,000 years, 90% of ocean life and 33% of land life perished.
So now the author of the Carbon Pollution story ties the Permian-Triassic Boundary extinction conditions to the present. Oh, wait. No he doesn’t. I guess we are just to assume the connections.
Okay, let’s make the connections ourselves.
The temperature was high and the oxygen level was low.
Granted today’s temperature is supposed to be high and getting higher but, even so, the temperature during the Great Extinction was 7–8° (C) higher than today. That’s a quite significant difference, but actually this was only about 4° higher than “normal” (over the preceding few hundred million years). Our present temperature is quite cool using the same “normal” but also for a norm averaged over a long enough period to include the last few ice ages. These differences are much too great to make a connection of any kind.
As for the reduced oxygen, let’s take a look at that. There is a world map, copied from another cited story [Decades of Data] which shows changes in oceanic oxygen levels over the last 60 years. The map show some areas where the O2 levels have increased (red) and some areas where O2 levels have decreased (blue). The text of the story implies the net result has been a decrease.
What is the concern of these authors? Is ocean life dying out or showing signs of stress? The article mentions a “potential to impact” marine life and refers to “more frequent ‘hypoxic events’” but supplies no figures. “More frequent” can mean double or triple or an increase of 0.0001%. Which is it? Is there any other negative or worrisome effects that have been found? No, nothing mentioned here either?
The main point of concern for these authors seems to be the fact that the change in these O2 levels “is about two to three times faster than what we predicted…” Oh. Well, how much did you predict? If you predicted a decrease of 0.00001% and the result was 0.00002% then, yes, that’s twice what you predicted but the question is: is it significant?
And how accurate are your predictions, anyway? Oops. I’m probably not supposed to ask that question.
The drop in O2 levels during the Great Extinction was around 50%. Yes, half the Earth’s oxygen supply had vanished. This can’t be compared in any way to changes measured in fractions of micromoles.
Finally, the author of Carbon Pollution refers to another story from the same organization.
Climate Change And Overfishing Are Driving The World’s Oceans To The ‘Brink Of Collapse’
This title is in the form of a logical fallacy that really irks me whenever I see it. “Cause A and Cause B are driving Effect E.”
The critically important question here is, “How much?” As in, “How much of the effect is caused by A and how much by B?”
Consider the headline “Torrential rains and automatic lawn sprinkling leads to massive flooding.”
The headline is true, as far as it goes. Lawn sprinklers that come on while it is raining would contribute, trivially, to any subsequent flooding, but the effect would not be noticeable or even measurable. The headline, while true, is misleading.
So is the story title also misleading? Difficult to say. But there is one statistic quoted in the Overfishing story: “Populations of the Scombridae family of fish, which includes tunas, mackerels and bonitos, have fallen by 74 percent due to overfishing.”
Does that mean the other 26% was cause by climate change? It doesn’t make that claim. Nor can it. There are many causes of falling populations, all of which will have greater significance than climate change. So why does the title group together the most significant cause, overfishing, with the least significant, if even measurable, cause, climate change?
To scare us.
This is not science. This is propaganda.
