[billfor]

I'm just clarifying parent comment that "1200 years of data is climate" by saying that longer periods also are climate data. I could have posted a graph of the holocene as well (I don't know that it would materially change my point). I made two points. The other was that we are in an ice age.

[kurthr]

Normally, discussions of climate refer to the last 12k year interglacial period as having come out of an "ice age". You're using the broader geologic term referring to any presence of any polar ice cap as an "ice age", which would cover the last 3 Million years. So what you're saying is that in the 300k years homo sapiens have never existed outside of an "ice age" and that the our speciation (eg in savannahs of Africa) was driven by the many glaciations of this current Ice Age? Even homo habilis hasn't been around that long.

That's saying that since the continents and earth's currents haven't changed, we're in the same age, AMOC is a minor technicality, and the oceans would need to rise to the straight of Panama to be significant.

[Retric]

No, climate is based on consistent weather data over a long period. Across long enough periods the underlying assumptions that make climate a meaningful thing to talk about fail due to orbital mechanics etc.

Plate tectonics for example shows you can’t even assume an area’s latitude is consistent, just look at the fossil history of Antarctica. Humans have dumped so much carbon and methane in the atmosphere even 100 years ago was quite different.

[wk_end]

It very much reads like you feel like you need to offer those particular points here to try to diminish concerns about global warming informed by the 1200 year Kyoto cherry blossom record. Is that not the case?

[billfor]

Yes I am diminishing the case of global warming about the tree. The tree they kept records of 1200 years ago is not the cultivated one seen in many parks now. That tree is about a million years old. Article just says "Kyoto’s cherry trees", which would include the old and new ones. Importantly, the new cultivated ones bloom earlier.

This could be a case of trying to make a climate argument, when the underlying data is more nuanced. Maybe we should just say it's nice the trees are blooming earlier.

[rafram]

The trees are unambiguously blooming earlier because of climate change.