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I am sure you have seen headlines similar to this, Worlds glaciers disappearing – Polar icecaps melting
at an alarming rate –West Antarctica ice sheet breaking up –Greenland ice cap on the verge of collapse, and it goes on and on. Diminishing ice has been
the most consistent argument used as evidence of a warming climate although it does not automatically point to an anthropogenic component of warming.
This link will take you to a news site with the headline "glacier melt worldwide now caused mainly by humans." This is disturbing, as the article only suggests that melting
has been 25% the result of human activity, and does not seem to make predictions of future melting other than that melting will likely continue for decades. The headline is misleading and deliberately biased.
I don’t think that all of these assertions should be taken as fact or as proof of an anthropogenic impact. There are a number of questions that should be addressed. I will try to express these questions and
refer to credible sources (by link) for opinions.
Are the glaciers disappearing? Well, it is definitely
true that most glaciers have been shrinking, or in other words, they are losing more ice by melting than they are gaining by snowfall. Measurements of atmospheric temperatures point to a gradual and reasonably steady warming in the past,
so it follows that melting is the likely culprit rather than a decrease in precipitation.
Since it is obvious that glaciers have been retreating since the beginning of this interglacial, the real questions are as follows. Is the process accelerating? Is anthropogenic warming increasing the rate of melt? Is a faster melt a relatively
immediate danger to humans or the environment? Are there factors, natural
or anthropogenic other than CO2 induced warming, leading to an
increased melt? Will the glaciers continue to retreat and for how long?
Are the polar ice caps rapidly
disappearing? I think that is a rather difficult prediction to make. Some have tried. According to the gospel by Gore, the north polar ice cap should have already mostly
disappeared. Others are saying that a catastrophic collapse of both the Antarctic and Greenland ice caps is imminent.
Well, currently (January 1, 2017) North polar ice may be as much as 10 % lower than the 1981 to 2010 average, this is a long ways from completely gone, and this at the end of a particularly strong El Nino year. Should that be expected? Is a 29-year average really valid? Where would it be if no humans were on the planet? Should we be worried, and about what? North polar ice is for
the most part floating. Melting it should not affect sea level significantly. Is there any basis here for predicting next years results, with an expected La Nina for 2017? Keep track of the ice here.
The Antarctic peninsula which juts northward towards South America
has apparently warmed about 2.5oC since 1950 which would make it the fastest warming area on the planet. I am a little skeptical since as far as I
know there are no permanent weather observatories on the peninsula and extensive satellite measurements (if they actually took measurements that far south) only began about
1979. Even more difficult would be determining temperatures from 100 years or so previous to that for comparison. Starting points are important.
Recently there has been a lot of attention paid to the West Antarctic ice sheet (WAIS.)
Remember the difference between an ice sheet and an ice shelf. The melting of an ice sheet has the potential to cause a sea level rise whereas a melted ice shelf should have no direct effect. Some scientists are saying that the WAIS is unstable and destabilizing
further and that it could completely break up in as little as a few hundred years though more cautious predictions are 2000 to 10000 years. There is evidence that this
has happened before during the early Pliocene when the temperature was warmer than today. It is thought this could result in a sea level rise of as much as 20 feet
although I am pretty certain this would require considerable melting of other ice sheets during the same time period. For more information follow this link. It also illustrates the wide disparity
between various viewpoints.
James E. Hansen, a senior NASA scientist and
leading climate expert said, "Once a sheet starts to disintegrate, it can reach a tipping point beyond which
break-up is explosively rapid." That may be true of ice shelves but I don’t think anyone has ever seen that happen to an ice sheet. If Dr. Hansen has, I would like to see some documentation and supporting observations. Once again, ice shelves are floating and their melting or breakup would have little effect on sea level.
Dr. Hansen’s use of the term explosive is unfortunate. It implies hours, days, or weeks when even he is talking in periods of hundreds
of years and others suggest time spans up to 10,000 years for a complete collapse.
Lets put a little perspective on this. Suppose
this happened in as little as 300 years (this is about what the most pessimistic predictors say, but does not seem to be supported by models.)
300 years you will be long dead, as will your great-grandchildren, and likely their great-grandchildren. If you really think that your descendants that far in the future will be unable to look after themselves in a different world, then I suggest you have
yourself sterilized. You will have no reason to worry about the future, at all.
And if it happened in 1,000 years or 10,000, who could possibly
give a damn. Do you think that our ancestors of 10,000 years ago had any concept of the world that we survive in today, or that they even thought about it? I am pretty
certain their primary thoughts were about their survival and comfort in their present time. And that is where our priorities should lay.
Is the Greenland ice sheet in danger of imminent collapse? Some would like to convince you that it is. Of course, their definition of imminent may be from a thousand to several thousand years. It is pretty certain that Green land
has lost a significant portion of its ice and has warmed in recent years.
Here, again, we need to define significant.
Greenland, unlike Antarctica, has a long history of human exploration and even settlement. There is evidence of people who have lived on Greenland on and off since 2500 B.C. The first Europeans (Vikings)
settled there about a 1000 years ago and even practiced some agriculture. Agriculture seems to be possible again but seemed highly unlikely as little as 20 or 30 years ago.
The early Viking settlers seem to have been driven off or killed off by the onset of “the little ice age,” a period in the fairly recent recorded history of unusually cold weather. That is also the point in history from which many warming alarmists like to start their graphics data
to show increases in the Earths temperature.
So we know Greenland is warmer than it was during the little ice age but likely no warmer or perhaps not even as warm as an earlier period. Make of that, what you will. In the meantime, the residents of Greenland are certainly enjoying benefits of a warmer climate.
imminent collapse, the Greenland ice sheet has more in common with the East Antarctic ice sheet in that it is grounded on solid ground, mostly above sea level, and is, as thus, more stable than the WAIS.
It does seem that the earth's poles with the exception of parts of
Antarctica have warmed quite a bit and certainly much more than the tropics or the more temperate zones. If this continues, it does not bode well for the integrity of the world's ice.
what does this mean to us? Very few people live in the Arctic and virtually no one resides in the Antarctic. That suggests the direct effect on human civilization would be very small.
The effect on other life is uncertain. Most seem to have adapted to a near complete meltdown, and back again, of polar ice in the past.
Plants do not need a lot of time to change their range, but some might get crowded out as their niche becomes more favorable.
It is difficult to see how a somewhat warmer climate would have much effect on northern animals. They currently survive seasonal changes
in temperature that can easily exceed 100ºF or 40ºC.
Most seem to have adapted to a near complete meltdown, and back again, of polar ice in the past.
Of course, if all the ice were to melt in the next year or so, sea levels
could rise so fast as to have catastrophic consequences. Could that happen? Almost certainly not. Even the more dire predictions envision a period from one to several thousand years. Well, if mankind cannot adapt to a warmer world, and higher
sea levels, in that time, then we deserve to go extinct (unlikely considering our roots.)
The human species appeared and evolved during the current ice age (Quaternary glaciation, Pleistocene glaciation.) They survived and even thrived, as global temperatures changed as much as 10oC.
Of course, humans have done the best since temperatures warmed to near current levels.
And are there possible benefits? Of course, there are, but many seem to think that the negative aspects would outweigh them. I am not so certain the negative aspects would outweigh the negative consequences of a rapid withdrawal from the use
of fossil fuel.
My own conclusion is that indeed the globe has warmed, and the worlds ice coverage is shrinking?
Will this continue at a rapid rate? I rather think not. Already the warming seems to have slowed, although I wouldn’t count on either continued warming, a stable state, or near future cooling. We are probably still emerging from the last ice age (glaciation,) and it should not be too surprising if we eventually lost most of the ice on the globe. This may not require more warming. The ice in your drink melts even after the drink has cooled. I doubt the danger is imminent.
Of course, it
would be not at all surprising if we were to eventually descend into another major glaciation (ice age.)
are a few of us, old enough and with decent memories, who remember when (the 1970 decade) scientists were scaring us with predictions of a rapidly approaching return of an ice age. It seemed pretty plausible considering past glaciations. I am certain that scientists today are not any more intelligent, although they do have new methods
and tools to lead (or mislead) them.
My prediction is that nobody will be completely correct about the
future climate and that most will be spectacularly wrong.
A few quotes from learned folks (presumably smarter than me.)
Prediction is very difficult, especially if it's about the future. – Niels Bohr
I try not to get involved in the business of prediction. It's a quick way to look like
an idiot. – Warren Ellis
I've been wrong on
everything about Trump; I've been wrong about everything on the Republican side of the ledger. But allow me - with that caveat - to make the prediction that Donald Trump will not be the president of the United States. It just will not happen. – Cory Booker
The public is
led to believe that the fashionable scientific dogmas are true, and it may sometimes happen that they are wrong. That is why heretics who question the dogmas are needed. — Freeman Dyson
It is easy to obtain
confirmations or verifications, for nearly every theory—if we look for confirmations. Confirmations should count only if they are the result of risky predictions... A theory which is not refutable by any conceivable event is non-scientific. Irrefutability
is not a virtue of a theory (as people often think) but a vice. Every genuine test of a theory is an attempt to falsify it or refute it. — Karl Raimund Popper
So, is the melting ice a problem? Possibly it is, but the greatest effects are likely far in the future, giving us lots of time to adapt.
in the far distant future, if humans still exist, we may be faced with trying to prevent another glaciation in order to preserve civilization.
it be stopped or slowed? It seems the earth is already warm enough to melt back the ice and has been for most of the last 10,000 years or more. Stopping the warming would not stop the melting. The onset of another major glaciation is the only thing likely
to reverse the phenomenon. I think we should be very happy the ice is melting, as opposed to the opposite.
We should be concentrating on making preparations and changing to suit a changing environment, just as the human species has always done, It would be wise to reduce the damage that we
do to the atmosphere, but we need to be certain of the consequences of our actions. Perhaps we could also work a little harder to repair some of the obvious damage we have done to the earth's land surfaces and oceans. Right now, that seems to be getting lost
in the frenzy over climate change.
This link for life on earth in a much warmer age