Incidentally, your critique also applies to literally most science, including very good and obviously successful science.
Can you really prove to your students that Intel doesn't have magic pixie dust it uses to speed up its processors? Probably not without expensive equipment your classroom cannot afford.
And can you reproduce the LHC experiments? Of course not.
edit: Here's the EPA website: https://www.epa.gov/climate-change-science/future-climate-ch... There are 5 references, all larger reports which themselves link into the actual literature.
The National Climate Assessment in particular is presented in the form of a slick website with hundreds of citations into the literature for curious readers: http://nca2014.globalchange.gov/report
The information is there, in extremely digestible form, and at the top of google search results. Naturally, reproducing the results of literally hundreds of cited papers is going to take you a while, but in most cases, there's nothing actually stopping you...
And here's a list of climate models, some of which you can download. The others have links to contact info: http://www.easterbrook.ca/steve/2009/06/getting-the-source-c...
It's also worth noting that scientists are usually fairly transparent about when they're guessing WRT effects of climate change and when they're pretty certain. The near-term stuff (~hundred years) is largely guess work based on simulations -- we can't do much better. The most certain prediction is that weather will become harder to predict. The longer-term stuff (~hundreds to thousands of years) is much more well-understood because there're historical records relating GHG levels to climate.
The biggest greenhouse gas by far is water vapor, not CO2. So it makes no sense to call a plot of CO2 a plot of "greenhouse gas concentrations". This type of "information" is low quality and will only make people not trust them.
A full description of the methodology and what exactly is being plotted is available in papers linked to here: http://tntcat.iiasa.ac.at:8787/RcpDb/dsd?Action=htmlpage&pag...
Anyway you can deny what I am telling you, but it is usual for people to go to supposed authoritative site like that, then check wikipedia and see H20 is the biggest greenhouse gas.[1] As a result they just shrug and figure no one knows what they are talking about, since they can't get the story straight.
Unless you're planning on boiling an ocean or great lake some time soon, humanity isn't directly effecting the amount of H20 in the atmosphere at appreciable levels as a first order effect. It's not a parameter under variation.
C02 equivalents are a parameter under significant variation, and as a first-order effect of human action.
We are interested in the dynamics of the system as we vary a parameter that we can, and are, directly manipulating.
Larger atmospheric, oceanic and whole system models then incorporate H20 and other effects in a simulation as the parameter we actually control is varied.
If this were explained on the page, you'd complain it was too technical.
> Anyway you can deny what I am telling you, but it is usual for people to go to supposed authoritative site like that, then check wikipedia and see H20 is the biggest greenhouse gas.[1] As a result they just shrug and figure no one knows what they are talking about, since they can't get the story straight.
Is that really common? I mean, there are actually a large population of people who will read [1] but don't bother to click on the link right under the graphic and see how the graphed data is used in climate predictions?
I'm highly suspicious that there's actually a significant population of people who are open to being convinced but make such a sophomoric mistake in their reasoning.
Someone can always find reasons to be uncharitable and dismissive if that's their predisposition. People with that predisposition and willingness and disregard evidence for even the most superficial of complaints aren't going to be convinced anyways.
I don't know whats going on with that chart, whatever. I am just telling you the end result of showing it to me, and doubt I am alone.
I don't draw straight lines on all my plots relating constants to (in)dependent variables. Even fifth grade science experiments follow this convention in their plots. It's an extremely common practice. Water vapor isn't being varied, so isn't plotted. Again, nearly every fifth grade science fair project follows this convention in their plots. It really does count as basic literacy.
For someone with some basic scientific literacy, the author's intent is obvious and confirmable by reading the literature. OBVIOUSLY the authors are aware of water vapor concentrations, and you can confirm this awareness with a superficial investigation into how this metric is used in models.
Sorry, but I do not believe a non-antagonistic reader would jump to the conclusion that climate scientists are unaware of tyoical atmospheric H20 concentrations. That's so far from the realm of reasonability.
At some point, the readers' good faith must be assumed or the entire expository enterprise is pointless. I think this plot is by far on the correct side of that line.
This is another contradiction to what I've been told: "Satellites have observed an increase in atmospheric water vapour by about 0.41 kg/m² per decade since 1988." https://www.skepticalscience.com/water-vapor-greenhouse-gas-...
We aren't actively and directly melting large quantities of ice. It's a second-order effect of increased atmospheric C02.
One option is to allow it to vary but not as a first-order effect. Another option is to simply not let it vary to keep the model simple.
Unless it can be made accessible to even science graduates to actually reproduce the results from a critical point of view, it's always going to have a lot of sceptics. Not everyone has so much faith in scientists.