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Comment by gwbas1c | Hacker News Reader

Based on where we are in the Milankovitch cycle, should we be getting warmer or colder?

(I keep checking the comments of this article hoping that someone knowledgable can explain how this impacts the climate.)

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NASA to the rescue: https://earthobservatory.nasa.gov/Features/Milankovitch/

Basically it's not measurable within a lifetime and the signal of human interaction with the climate is magnitudes higher.

It is extravagant and ludicrous to claim that the signal of human influence (CO2 ppm?) on the climate is magnitudes higher than that of the Milankovitch cycles -- which have been driving the regular glaciations and interglacials over the last 3 million years.

That said, we do use ice cores from periods that would cross multiple of these cycles. If these cycles change how we estimate those values, then the statistical models we’ve built based on them will need to adjust accordingly. So, it’s not that it doesn’t have an impact, just that the impact probably doesn’t change the trend line.

Do the math...

PBS space time did an episode about the cycle

https://www.youtube.com/watch?v=ztninkgZ0ws

There are multiple cycles in that theory, not just one, so the influence on our climate depends on the periods of all these cycles, and involves potential amplification due to their harmonies. The largest observed signal in the geological record of the last 3 million years is a ~100k cycle of interglacials within an Ice Age.

Accordingly we should expect the current interglacial to end "soon" and enormously thick ice sheets shall grow again -- we're 12k years into the Holocene; the last interglacial lasted 15k years.

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