Climate change, when it comes to our our global dilemma referred to as "Climate Change," isn't the real issue. It is, ultimately, an effect.
Nor, by suggesting that "climate is changing" (which it does throughout geologic history) does it capture why it is a problem.
A far bigger problem with this phrase is it directly ties the problem, and our sense of it, to what we see in the climate around us. And, while climate scientists are always telling us to be concerned about the future, it invariably ties our sense of how "bad," or "major," the problem is, to the climate we are experiencing now. The rest is all "conjecture," or seems like it.
So what is the real problem?
Long lived atmospheric greenhouse gas levels are increasing. Everyone knows that, right? But that's not the problem either. The problem is almost never reported, and, probably as a result, is also not very widely known.
This is odd, on an issue that much of the world seems to have a very strong, often passionate, opinion on. (Whatever that opinion may be. And if you've made it to this blog/information site - or even if you haven't - you know those opinions vary. Greatly.)
It is also extremely problematic. For everyone. Because acting (or not acting) on bad or critically incomplete information, leads to the wrong kind of action (or non action), as well as the wrong kinds of discussions, arguments, and considerations to begin with.
The problem can be captured in a single sentence. But let's build up to it, with the basic reasons why that single sentence, almost never uttered or heard, is such a big issue.
Higher concentrations of long lived atmospheric greenhouse gases prevent more heat from escaping earth's atmosphere. More retained atmospheric heat, even if a minute amount, impacts several major direct earth systems which are heat energy responsive.
Most of these play a huge role in or otherwise drive climate: Such as snow cover, and what, along with ice, sand, water, deforestation, etc. it greatly affects, namely, earth's surface albedo, or measure of reflectivity; ice caps; sea ice; oceans; and atmospheric heat re-radiation - the initial driver of these affects - which when large enough is exacerbated or self reinforcing by extra melting, which in turn releases more trapped carbon dioxide and methane, two major greenhouse gases, which in turn of course creates more atmospheric heat re-radiation, causing more melting, etc; and of course - though secondary to any impact large enough to make fundamental changes in any of the basic drivers of or major influences upon climate - there is the increased average retained heat in the atmosphere itself.
(Atmospheric albedo, which is really just part of the earth's total albedo, or reflectivity, of course plays a large role also. But due to cloud formation and dissipation - a result of climate and not a driver of it - it is always changing. It also represents a generally positive - but still somewhat unclear - increased warming feedback loop: More cloud cover increases overall albedo and reflects back or diffuses more sunlight before it even his the earth. But the water vapor it is comprised of, due to high concentrations levels, acts as a very potent greenhouse gas. Both during the day, when the increased cloud cover is also simultaneously having a sunlight blocking, and cooling affect. And at night, when it is not.)
Note that painting the roof of your house white versus brown has the same type of impact. The white has a higher albedo, or reflectivity, so more heat is immediately reflected off instead of absorbed. And some of that goes into space, so there is an infinitesimally small (diminishing) impact upon total retained heat by our earth atmosphere system.
Climate is in fact ultimately a reflection of the energy input from the sun, which shifts a little but otherwise is usually within moderate ranges of output (which, though over a period of hundreds of millions of years, is very slowly increasing), and all of these things on earth, such as white roofs, tree cover, macadam, open water, ice, snow, tree cover, open fields, etc., that affect how much of that received sun energy is retained. (Making idiotic by this alone the initial question as to whether man kind was affecting the climate - though it has been repeatedly asked anyway.)
And which, before man came along and became moderately modern - chopping down a lot of forest and leading to a lessening of the major land sink for atmospheric carbon, and starting it all off - was, at least in comparison to our current best expectation, in shorter chunks of time at least, relatively stable. (At least, absent the occasional wild dust spewing and atmospheric blocking volcanic eruption, large meteor or asteroid impact (which ostensibly led to such major climate changes that it ultimately helped wipe out the dinosaurs, in of the great mass extinctions in earth history), or change in some other pattern that led to a large shift in greenhouse gas concentrations, or ice buildup.)
It is, pertaining to these things, of course a question of degree. (No pun intended.) And that degree, of late, and not just in modern terms, but more critically, in far broader, "geologic" terms, has been huge.
We're not particularly good with scope. Numbers scope. (Quick, visualize a pile of a million pebbles. Now visualize a trillion. Was your second pile really a million times larger than the first pile? What did it look like in comparison to the first?) Or, more generally, science scope.
But the scope of change in greenhouse gas levels - the same gases that are responsible for the earth not having an average temperature of below zero - have not, unlike say the shifting of color of your house or building's roof, been infinitesimally small, nor even minor; but, geologically speaking, they have already been radical.
That is, atmospheric concentrations of the long lived greenhouse gases that ultimately determine how much of the heat reaching the earth and re emitted gets re radiated back to the rest of the atmosphere and back downward, rather than out into space, have now reached levels not collectively seen on earth in several millions years. That, as stated in bold, is the problem. That, is the issue.
More importantly even, from our perspective anyway, the change has been super fast. And while the levels of one of these long lasting greenhouse gases - the major one, CO2 - was fairly high (in part due to where it happened to be under the generally far slower, undulating fluctuations over the minor eons, and in some part due to all the deforestation over Europe that had already occurred), all of this multi-million year change has occurred over a time span that represents well less than one one-thousandth of it: A couple hundred years; and much of that change, in the last half century alone. A half century equals 50 years. Several million equals (X)X,000,000 years. Big, difference.
That, is what the problem is. Along with, when it comes to being reasonably able to do anything about it, the fact that we are still adding to the level of these changes - making them ever more radical still - at still breakneck speeds.
Carbon Dioxide, the main (and most commonly known) Greenhouse gas, has already alone hit levels probably not seen on earth in three million years.) nitrous oxide, methane, and a far more sparse but still powerful long term greenhouse gas type, chlorofluorocarbons and hydrochlorofluorocarbons (both completely man-made and thus unprecedented), have also spiked, adding greatly to the overall collective effect.
For instance, here's a chart of atmospheric methane levels, going back almost a million years, which shows that the range was relatively small over the entire period, and then in geologic terms it has suddenly gone straight up (EPA).
Notice the very tail end of both geologic historic charts (the ones on the left) - they both go straight up. And the by far more radical of the two - methane - also happens to be the more important of the two, second only in importance to carbon dioxide. And, though relatively short lived (it breaks down into carbon dioxide though), methane is gaining in importance on carbon dioxide, as more and more carbon, trapped beneath long frozen but now slowly melting surface ice and snow, is released in the form of methane.
We don't have as precise readings on these levels beyond about 800,000 years, but while from deposit sink records methane levels have fluctuated highly well back in the geologic past, these are on the order of many million year fluctuations, and there has been nothing to indicate that methane levels (or nitrous oxides) have approached today's levels in a few to several or more million years.
But the more important point is that the main greenhouse gas, carbon dioxide, is at levels, and still fast rising, now likely not seen in three million years, (Though estimates vary from between two million, to ten million, years.) And it is unlikely that the collective affect of the other, lesser, but still important greenhouse gases (including the man made ones that of course didn't even exist) was even as high back then as it is today; meaning that the total collective level of long lived greenhouse gas concentrations in terms of their net heat re radiating affect, or atmospheric long lived heat trapping gas quotient, is probably higher than it has been at any point in the last several million years on earth.
As Bob Ward, policy director at the Grantham Research Institute on Climate Change and the Environment at the London School of Economics, reported in Bloomberg News, puts it, "We are in the process of creating a prehistoric climate that humans have no evolutionary experience of."
This is key – conditions were very different the last time the atmosphere had this much re-radiation intensity, and in particular were very different – and the REAL problem here - from the conditions under which we, and the species, we relied upon, evolved (and spread out over land above sea level, upon).
Ward goes on to point out, that three million years ago, "temperatures were 2 to 3 degrees Celsius higher than pre-industrial times, the polar ice caps were much smaller, and sea levels were about 20 meters (66 feet) higher than today."
Or at least 30 feet. They're both, however, bad. For us, anyway, and at least some of the species that currently share the planet with us. Not for the planet as a whole. (Which couldn't care less one way or another. It's a planet. Not a life form.)
If this, or at least some effect toward this end, is the likely result, you may wonder why we have not seen it. A powerful hint is found in those seemingly mundane charts just above. It is also found in a chart of Carbon Dioxide levels going back over the same 800,000 year level. Key in on the very last part:
On a geological scale, all these changes are all but immediate. The idea that we would see whatever result is going to occur within years of its cause, is based upon a naturally very man-centric sense of geologic and physical time; which might view 50 years as very long, whereas in geologic terms, it's next to nothing.
The affect of increased trapped heat is not immediate in terms of our perception, because there are multiple relatively stable stases conditions on earth - such as, in terms of our climate - the oceans, ice caps, and total surface albedo, mentioned above. All of which, increased re radiated ("trapped" heat in the atmosphere), over time, starts to alter. Slowly at first, then, more quickly, as the longer term climate stabilizing affects start to lessen as a result.
We are already starting to see the first signs of both patterns. Both the affect, and its beginning acceleration. Such as in the melting of Arctic ice, ocean warming, and slight, but also seemingly increasing, softening and melting of the Northern permafrost.
The issue is not "if," as it is often portrayed. But "when," and "how much," almost none of which can be prevented, other than possibly through massive atmospheric remediation. (Such as playing Frankenstein with the skies even more radically than we already have, albeit on purpose this time; and something we might one day have, and very likely will, to some degree try to resort to.)
The major problem now is that we are still adding to this, and rapidly. And for the same reasons briefly gone over above, each unit of increase will increase the problem by increasingly larger amounts. That is, more trapped atmospheric heat will only further lessen the earth's long term surface albedo, further reflecting less heat energy, and absorbing more of it directly into the surface, etc.
It's not a perfect equation, in fact no one knows the equation, or possibly can. But from the basic geophysics of the issue, it is, most definitely a compounding if not moderately exponential problem. Hence, continuing to add more to it now = really bad idea.
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