Old_Man wrote:Why do we rule out rapid warming events yet want to include other rapid warming events?
I've already stated the reason for ruling out D-O events more than once.
Though typically a Dansgaard-Oeschger event takes 1500 yrs?
D-O events cause rapid warming on the decadal-century scale, and as such are the only natural events (should they prove to indeed reflect global increase) to come close to anthropogenic observed and projected rate of warming. Their periodicity is not the same as their rate of warming.
Please read the raw Vostok (or others) icecore data.
Don't do that.
Depth (m) 202-200
Sample ages 8226 to 8135 YBp (span of 81 years) Please note, the cores where taken in 1999 so another ~9 yrs should be added (not sure which month it was pulled).
Temperature changes from -0.87 deg C to + 2.06 deg C
An anomaly change of +2.93 deg C in a span of 81 years. I assume an 81 yr event counts?
If it isn’t an outlier... However, DOME C doesn’t show the same jump, meaning that such warming didn’t even extend across Antarctica itself let alone the globe. Looking at the range of temperatures before and after, it’s clear that the 8135 reading is an outlier that isn’t reflective of a meaningful trend.
EDIT to add:
And of course the idea that such warming was global is refuted by the numerous records suggesting an 8.2 ka NH if not global cooling event, likely related to a slowdown of the- what else- thermohaline circulation.
or am I cherry picking and this is a D-O event we should discount?
You don’t seem to understand the terminology you’re using.
.... 128357 YBp the temp was 3.23 deg C above 'norm' or 2.52 deg C higher than summer of 2007 anomoly (I picked it since it was a high anomaly).
I'm missing the extreme? I don't need to write a paper...the data is out there.
Yes, temperatures warmer than current are well known. However, the changes don't occur in less than 100 years. You have to go 1,000+ years in either direction to get a change of +3C. This is the point we keep having to drive home over and over. We could easily see +4C of warming by the end of 2100 without mitigation.
Paleoclimatologists theorize that it would take many years (decades?)of plus 2 degrees C to melt both ice caps. So I think we have a way to go.
Decades at least, yes. It’s not a done deal. That’s why mitigation is crucial. We still have enough time to prevent it.
Yes, CO2 is a greenhouse gas. I do not deny humans (as I stated before) have caused a plus 100ppm increase over the last 100 years.
And what is the resulting change to radiative forcing such an increase necessitates?
BUT temperatures are NOT following....thus I am dubious....
I don’t understand this. Based on what? Less than 5 years?
want to talk water vapor then we may have something
Water vapor acts as a feedback, not a forcing. Increased on its own, it precipitates out in a week. Some other forcing has to raise temps in order to increase water vapor influence over a meaningful time frame.
In the interest of not driving everyone insane with a discussion that really does not address the original purpose of this forum...I will shut up and let you have the last word....
Some people seem to be very interested in the subject. For their benefit, I’ll keep the discussion going as long as there are questions, comments, etc.