[Yetanfou]

You use terms like climate denial and climate science as if they mean something. You also simply state that we are right and they are wrong as well as give an emphasized hint that the data supports your claims.

If you read what these people (and many others with them) say you'd see that they also claim their position is staved by the data. They call for an opportunity to discuss these matters in public, without being shunned in the way you just did. If their ideas are as faulty as you seem to think they are your side would have nothing to lose by going into this discussion.

This rhetoric is part of what makes the 'climate change' movement look like a religion. Blind discipline, a statement of fact which can not be discussed, shunning of those who dare to differ, making a clear us versus them distinction with terms like climate science versus climate denial. You can even buy off you sins by paying for climate compensation.

Yes, the climate is changing as it has been doing for as long as there is a climate. Human activity has influence over the climate in many ways ranging from soot deposits on snow and ice fields (which warms them up) through local warming by direct emission to the emission of IR-active gases like CO₂ and CH₄. The role of CO₂ is disputable, it is not a strong 'greenhouse gas'. CH₄ is a strong greenhouse gas, as is water vapour. Condensed water (in the form of clouds) has the opposite effect by raising the planet's albedo (reflection coefficient). The amount of CO₂ in the atmosphere has risen since the end of the little ice age, partly due to human activity by burning fossil fuels, partly due to the increase in sea water temperature. How much of the rise is due to human activity is unclear, estimates range from 15 ppm (i.e. hardly anything) to nearly everything. The models used by the IPCC are incomplete (as all models are) and the predicted rise in global temperature turned out to be overstated by a large margin.

In 1972 a group of scientists at Brown University decided the science was clear on the fact that (I quote) the present rate of the cooling seems fast enough to bring glacial temperatures in about a century, if continuing as the present pace and sent a letter to then-president Nixon to warn him of the consequences of a global deterioration of climate, by order of magnitude larger than any hitherto experienced by civilized mankind. They were right in that a new ice will come but they were not correct in their estimate on when that would happen - Nixon did not have much to worry over in that respect.

There was no global public internet in 1972, there were no social media, there was no opportunity for celebrities to signal their social engagement and virtue by standing up and proclaiming that the time had come for all good men and women to act now or risk freezing in the impeding global climate catastrophe. The ice age scare largely was confined to a group of scientists with a few articles popping up here and there about increasing glacial masses and early winter snows. Had there been a global public internet in the early 70's and had Joan Baez, Sly and the Family Stone, Jimi Hendrix, Crosby, Stills, Nash and Young, Joni Mitchell and all the others spoken up... who knows what this would have led to. Imagine a second Woodstock 'for the climate', the public chanting 'no snow no snow no snow' instead of their previous rain-obverse incantation. Just imagine.

Also, don't treat this subject like a religion. It isn't. It is an important subject which should be subjected to all the rigours of the scientific method. That method does not tolerate dogma nor the shunning of differing voices. It is the observation which disproves your hypothesis you want to look for, not the opposite.

[Beltiras]

It's not a religion. We not only have data we also have the visceral reactions when confronted with real-world examples of what climate change is doing right now.

I was a bit shocked when I heard that the Greenland glacier is melting from the bottom. Arctic waters are feeding energy under it. It is melting at a higher rate than ever recorded before [1].

Here's a fun fact. Last 5 years are the hottest on record [2].

Tuvalu is sinking [3].

This isn't theoretical anymore. The change is coming, fast.

[1] https://www.economist.com/graphic-detail/2019/06/17/the-gree...

[2] https://www.nationalgeographic.com/environment/2019/02/2018-...

[3] https://edition.cnn.com/interactive/2019/05/world/tuvalu-cli...

[Yetanfou]

Glaciers always melt from the bottom (or at least appear to do so) since that is where the water goes. Parts of Greenland's glaciers are actually growing [1].

Here's a strange fact: the last 5 years are only the hottest on record when compared to recent historical temperature data. Compared to previous historical temperature data (over the same period) the last 5 years are comparable to but not as extreme as the hot period in the mid-30's. This discrepancy started when meteorological institutions in parts of the world started 'correcting' their historical temperature records. The claimed reason for these corrections - which lower past temperatures while raising recent ones - is that they are necessary to make historical measurements comparable to recent and current ones. This claim has been tested and found wanting in the case of the Dutch meteorological office, KNMI [2 (in Dutch)]. NOAA in the US does the same type of corrections which are being criticised for being excessive but I have not yet found an impartial and detailed report laying out where exactly they went wrong.

Finally: Tuvalu is growing, not sinking [3].

[1] https://www.nationalgeographic.com/environment/2019/03/one-p...

[2] https://klimaatgek.nl/document/De%20homogenisatie%20van%20De...

[3] https://phys.org/news/2018-02-pacific-nation-bigger.html

[Oletros]

In the 70s, the scientific consensus was global warming, not cooling.

>Yes, the climate is changing as it has been doing for as long as there is a climate

This is irrelevant for the current trend

> The role of CO₂ is disputable,

I suppose you have data to back this claim, isn't? > The models used by the IPCC are incomplete (as all models are) and the predicted rise in global temperature turned out to be overstated by a large margin.

I suppose you have data to support this claim, isn't?

[Yetanfou]

> In the 70s, the scientific consensus was global warming, not cooling.

Consensus is irrelevant here, in the 1800s the consensus was that radiation travelled through the aether. This did not make it true even though it was the consensus.

> This is irrelevant for the current trend

Of course it is relevant for the current trend, it is those historical events which can be used to check climate models. This goes for both recent history (where direct measurements exist) as well as ancient history (where measurements need to be derived indirectly).

> I suppose you have data to back this claim, isn't?

Why, yes, there are many examples. There are many articles pointing out that CO₂ concentration seems to lag behind temperature changes instead of the other way around:

[1] "Temperature and atmospheric carbon dioxide are significantly correlated over the past thirty years. Changes in carbon dioxide content lag those in temperature by five months."

[2] "High-resolution records from Antarctic ice cores show that carbon dioxide concentrations increased by 80 to 100 parts per million by volume 600 ± 400 years after the warming of the last three deglaciations."

[3] "The lag was calculated for which the correlation coefficient of the CO2 record and the corresponding temperatures values reached a maximum. The simulation yields a lag of (1200 ± 700) yr."

[4] "The start of the CO2 increase thus lagged the start of the [temperature] increase by 800 ± 600 years."

[5] "Over the full 420 ka of the Vostok record, CO2 variations lag behind atmospheric temperature changes in the Southern Hemisphere by 1.3±1.0 ka"

[6] "The sequence of events during Termination III suggests that the CO2 increase lagged Antarctic deglacial warming by 800 ± 200 years and preceded the Northern Hemisphere deglaciation."

More on the 'greenhouse potential (GWP)' of CO₂ (and other IR-active gases like CH₄ and N₂O) in "Analyses of IPCC’s Warming Calculation Results" [7] et al.

As to the overestimation of the temperature increase all it takes is a look at the average temperature development versus the predicted temperatures to see the discrepancy. Some articles detailing this discrepancy:

[8] "Actual temperature measurements of 1958-2017 from three weather balloon datasets were compared to all 102 model runs. ... The mid-tropospheric warming trends in the models are caused by increasing water vapour in response to rising CO₂ levels due to flawed moist convection thermodynamic parametrization. Correcting the parametrization to match the temperature and water vapour amounts would greatly reduce the model’s climate sensitivities by reducing the water vapour feedback net of the smaller lapse rate feedback."

[9] "Why models run hot: results from an irreducibly simple climate model"

There are many more articles which pose questions around the accuracy and/or validity of the models on which the climate catastrophe hypothesis is based.

[1] http://www.nature.com/nature/journal/v343/n6260/abs/343709a0...

[2] http://www.sciencemag.org/cgi/content/abstract/283/5408/1712

[3] http://www.agu.org/pubs/crossref/2000/1999GL010960.shtml

[4] http://www.sciencemag.org/cgi/content/abstract/291/5501/112

[5] http://dx.doi.org/10.1016/S0277-3791%2800%2900167-0

[6] http://www.sciencemag.org/cgi/content/abstract/299/5613/1728

[7] http://www.jcbsc.org/admin/get_fileenv.php?id=110

[8] https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/201...

[9] DOI 10.1007/s11434-014-0699 (Sci. Bull. (2015) 60(1):122–135)

[eesmith]

Consider this through the lens of Young Earth Creationism vs. evolution.

The supporters of YEC claim their position is supported by data.

I think YEC's are flat-out wrong, and the physical evidence is so highly weighted in favor of old-Earth evolution that it's fantastical that they can maintain their position.

YEC's "call for an opportunity to discuss these matters in public, without being shunned". However, their positions have long since been demonstrated to be without basis. What YECs are looking for is fame, and influence, which they get by having a public debate 1) where the premise is that there is an argument, when there isn't, and 2) where people aren't permitted to call out the ridiculousness of their arguments.

You say the efforts of "the 'climate change' movement look like a religion". YECs say that evolution is also a religion.

Supporters of evolution have demonstrated that the YECs arguments are invalid. YECs repeat those arguments to new people, which shows they are not interested in the actual validity of those argument.

Your 1972 Brown University example parallels that structure. As https://skepticalscience.com/What-1970s-science-said-about-g... points out:

>> A persistent argument designed to discredit the field of climate science is that scientists predicted an ice age in the 1970s. So popular in fact that it ranks an impressive #7 in the most cited skeptic arguments. The logic goes that climate scientists got it completely wrong predicting global cooling in the 1970s (it started warming instead). Hence climate science can't be trusted about current global warming predictions. Setting aside the logical flaws of such an ad hominem argument, was there any consensus among 70s climate scientists predicting global cooling? ...

while a study of the scientific consensus in the 1970s shows:

>> in fact, the large majority of climate research in the 1970s predicted the Earth would warm as a consequence of CO2. Rather than climate science predicting cooling, the opposite is the case.

You write "The ice age scare largely was confined to a group of scientists with a few articles popping up here and there". While the evidence is quite the opposite - from the same link:

>> a 1975 Newsweek article The Cooling World that suggested cooling "may portend a drastic decline for food production ... A 1974 Times Magazine article Another Ice Age? painted a similarly bleak picture

It appears that the popular press did more to raise an ice age scare than the peer-reviewed scientific press.

Since you want "the rigours of the scientific method", surely you should apply that rigor to your own statements. Was the consensus of climate models of the 1970s really that of global cooling? Or are you repeating an argument long shown to be wrong?

What is the basis of your understanding of the 1970s climate models? Was it a cherry-picked minority viewpoint selected by climate change denialists more interested in fame and influence than the validity of their arguments?

[Yetanfou]

The comparison between YEC and evolution falls flat on its face because of the actual physical evidence in support of evolution where creationists have to call upon acts of god to support their hypothesis. It was god who put the dinosaur fossils in the soil to test the faith of his flock, it was god who twisted the laws of physics in such as way as to make it possible for cosmic background radiation to appear to show the universe as it looked ~14 billion years ago, etc. This dichotomy does not exist in the debate between the proponents of a climate catastrophe and those who do not hold with this hypothesis. Both sides call upon what they see as evidence for their stance, in this case the evidence mostly consists of models. Those models are both coarse-grained and limited in the factors they take into account. When tested against historical data the models have shown to grossly overstate the warming effect, they also leave out some important factors like cloud cover where a ~2% increase in cloud cover can negate the calculated warming effect so it is definitely a factor which should be included.

Creationists are driven by religion. They may claim that evolution is also a religion but that is just playing with words and has no relation to the stand-off between those who support the climate catastrophe hypothesis and those who don't. In the former case religion was the main driver from the start, in the latter the movement got its start based on scientific studies. The current climate catastrophe hypothesis is not the first, there have been several predecessors. Some of these got some traction - the global cooling scare of the early '70s is one of these - while others languished. The religious undertone only became a factor in the current climate catastrophe hypothesis when it was picked up by mass media, celebrities, politicians and business interests who latched on to some parts of the IPCC reports and ran with it. Where the normal discourse in science, although heated, still remains open for discussion and by necessity for falsification, the non-scientific proponents of the climate catastrophe hypothesis had and have no such qualms. It is from there the claims of '97% of all scientists agree' and 'we only have 10/12/15 years left' arise, is is that group which coined the label 'climate denier'. The involvement of political groups in positions of power has made it a potentially career-limiting (or rather 'funding-limiting' but it comes down to the same thing) proposition to openly go against what is now becoming the dogma of the looming climate catastrophe.

This is not how science works. When a model has been proven to give the wrong results you adjust the model, you don't base policy on it. The models used by the IPCC have shown to overestimate warming by a large degree so they clearly are not showing the whole image. The reasons for the over-estimation can be several, most likely though is that the models don't take a limiting factors into account, cloud cover being a possible candidate. Instead of silencing those who follow the normal scientific method by falsifying a hypothesis these results should be taken into account and weighed for their validity, even when they come from a group which is ideologically opposed to yours.

Climate change is a real thing in the past and present, there is hardly anyone who denies this. Catastrophic climate change is a hypothesis. Anthropogenic catastrophic climate change is another hypothesis. The path from hypothesis to theory goes through attempted falsification, there is no other valid way. When presented with what is claimed to be a successful falsification the reaction should be to test it and when found valid lead to something like "well that is interesting, it looks like we missed something" instead of "go away heretic, we don't need your type around here". The former leads to better science, the latter to Lysenkoism.

[eesmith]

Creationists say there is actual physical evidence in support of creationism.

Your "test the faith" example for the dinosaurs is at best incomplete. https://www.icr.org/article/how-do-dinosaurs-fit-in/ is an example of a YEC justification which does not use that argument.

My point was to say that your arguments are weak, because they apply equally well to those who defend creationism.

You again write "the global cooling scare of the early '70s is one of these".

As I pointed out, this was primarily a scare in the popular press of the time, while the general consensus in scientific literature was that increased CO2 would lead to global warming.

What you are spreading is, and I quote again, "#7 in the most cited skeptic arguments", and demonstrated to be an invalid argument.