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Comment by tejohnso | Hacker News Reader

Makes me cringe a little bit when global warming presentations start out with a co2 vs global temperature chart. Especially if that forms the entire basis of the analytic part of the presentation. Because I know someone (most) is just thinking "correlation != causation" and dismissing the entire thing.

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But in this example we know that there indeed is a correlation between greenhouse gases and temperature. Of course you cannot restrict your argument to that, but at some point you start with some axioms.

Yes; interesting that they never bring up the chart showing we’re at the peak of a natural 125,000 year temperature cycle.

Source? The long temperature graphs I've seen look quite irregular, rather than cyclical.

Here's the smoking gun graph he's hosting: http://donath.org/Photos/TempChange.PNG

This is what he's talking about: https://en.wikipedia.org/wiki/Milankovitch_cycles

Here's a graph similar to his, hosted on German Wikipedia: https://de.wikipedia.org/wiki/Milankovi%C4%87-Zyklen#/media/...

Nobody brings it up, because scientists don't believe the observed changes in temperatures are due to Milankovitch cycles, since global warming is happening on the order of decades and not millenia.

Here's NASA's take: https://climate.nasa.gov/ask-nasa-climate/2949/why-milankovi...

Scaling the time axis sensibly will quickly reveal that the rising temperature and this cycle cannot explain the rise we see.

There are certainly overlapping effects, but the model would fail to predict temperatures.

> global warming is happening on the order of decades and not millenia

How do we know that temperatures inferred from ice-cores (or whatever) are not extremely smoothed due to natural phenomena? Can we really get resolution down to individual years such that they agree across different test sites and methods?

Well for one thing we don't have tens of thousands of years to wait for a natural ice age to counteract industrial warming that has happened within the past century or two.

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