Re: Data in context
>'because of man-made global warming'? Near-hysterical speculation! That was where I stopped reading.
Your indignant response with "Near-hysterical speculation" to people that know what they are talking about prompted my indignant response.
I'm sure you wouldn't dismiss a recommendation for heart bypass op as "hysterical speculation" if 98 of 100 heart specialists said you needed one, while your car mechanic says don't worry, "ignore it", or "it's just stress", "it's happened before", "look squirrel!", "pain is good for you".
We don't know 'exactly' what is wrong with the climate, but we'll nail it in the autopsy.
Climate scientists know their stuff in their fields as well as any other professional does in their respective fields, and their advice should be taken seriously.
Imagine you're writing a program... some oik of a manager comes up to you and says that input validation is unnecessary because it'll cause a dev budget overrun, and that no-one would possibly enter an input combination that could compromise the system... I think you would have something to say on the subject because this is your profession, and you know what you are doing. However, they won't listen to you because they can't comprehend risk - that a breach could bring down the entire company, and anyway, validation is a liberal thing that may lead to validation taxation. (I'm sure there's a better metaphor but I can't think of one now!)
> To state that the Arctic sea ice has shrunk dramatically over the last several decades, because of
> man-made global warming is at best misleading and at worst a lie.
*No* other explanation comes close, other than a massive injection of anthropogenic GHGs, mainly CO2, and there is 40% more of it in the atmosphere since we industrialised.
Even with a solar minimum over the last couple of decades, global temperature has been rising, and disproportionately at the poles due to polar amplification.
There is no other heat source than the sun, and warming doesn't happen by itself, so it must be because the reradiation of excess heat is being impeded, by a change in atmospheric composition. An extra 40% of a known GHG, CO2, is a significant change. To infrared, CO2 absorbs infrared as ink absorbs light.
The concentration of CO2 is small, but considering the thickness of the atmosphere, it represents a layer of CO2 about 4m thick, or a couple of millimetres as a solid. This is enough to significantly block IR radiation from the Earth, and we have increased it by 40%. Satellites measure the increase in nocturnal ground temperatures, and the decrease in stratospheric temperatures because less IR radiation from the Earth is reaching it.
Difference represents about 0.6W per square metre, but there are trillions of square metres, and this delta adds up to an astronomical amount of energy that is not being dissipated to space.
Over many years, things start happening, as we are observing now.
> However, to state that the shrinking of the Arctic ice is consistent with global warming would perhaps be accurate.
>These two statements are worlds apart and mean very, very different things.
Pedantically true, however, jumping off a tall building and decorating the pavement would also be consistent with the existence of gravity.
The rising energy budget of the Earth cannot be explained without our CO2, there is nothing else and 90% of this energy is going into the oceans to reappear many years later.
>Or do you really believe that global warming always equates to 'man-made global warming'?
That is silly. Of course not. Climate changed very much over geologic time-scales since the planet's birth, but that was not *our* world. The evolution of life, and the planet's biosphere and climate was also causally interdependent, but proceeded at a pace that allowed a fair proportion of species to adapt in time. Lucky for us.
All life here is adapted to the finely-balanced climate we have now. It is naturally comfortable and we can't easily imagine any other, but its scope is still a fraction of the range of climates possible with just tiny tweaks in parameters.
Fortunately there have never been any sudden events that completely extinguished life, or boiled away the oceans - yet.
It is a complicated system, with many balances, annual and multidecadal responses to inputs, negative and positive feedbacks, with known and unknown latencies and states. A "known unknown" is the massive deposits of methane clathrates, currently stable, but only because of a few degrees - a few extra degrees to cause a massive and rapid outgassing would lead not to climate change, but to climate destabilization, which doesn't bear thinking about - I really don't think it is something we should be dismissing out of hand with "global warming is a hoax" stupidity, when it is absolutely the most serious threat that mankind faces, in addition to eating itself out of house and home (search for "mouse plagues" on you tube - the logical hyperbole, but our civilization would collapse back to the stone ages before anything on that scale would happen)
However we have had a monumental impact over the last century and particularly the last 50 years, by burning fossil fuels as fast as it can be extracted, and deforestation as fast as humans can cut and process, with a population explosion and massive resource depletion.
There is no other explanation for the incredible Arctic melt - it is our CO2 - don't dismiss it out of hand - there are thousands of peer-reviewed papers on the subject, of which I'm sure you are aware, if you are really interested in the subject.
I just watched this, and recommend it for you if you have an hour and can afford popcorn - Professor Robert Manne is spot-on with his analysis:
It is only in English speaking countries that AGW denialism is so rampant - the fossil fuel companies, right-wing think-tanks, opportunist hacks and Murdoch funded news disinformation campaigns have been spectacularly successful in subverting knowledge, public opinion and democracy, and I venture to suggest that you and many here are victims, or even complicit. (I am at a loss to comprehend why the general attitude here is uncharacteristically denialistic, considering IT professionals like myself are intelligent and pragmatic)
Personally, I have been an out of the rat-race expat in a non-English speaking country for many years, and not exposed to their bias, so I could educate myself with real information.
The jury is in on AGW, the evidence is overwhelming and unequivocal, and I am still gobsmacked that there are people denying it.
It's like a Pythonesque Dead Arctic Canary sketch, an affront to sanity except it is deadly serious without any element of humour.