Translate

Saturday, September 23, 2017

Global Warming: Milankovitch Cycles

'Global warming skeptics' like to point out that previous interglacial periods achieved global temperatures a bit higher than what we have yet to experience. This is true. And interestingly, the probable reason that Earth has not experienced those higher interglacial temperatures this time around is the comet strike that induced  the 'Younger Dryas' mini-ice age 13,000 years ago which dampened the interglacial warming that had begun just before the comet strike. 

Since it's true that the higher previous interglacials' temperatures came about without the influence of artificially high CO2 levels, we know that these were the result of the natural Milankovitch cycle. 

We should note, however, that natural temperature changes induced by orbital variances do NOT occur so rapidly as what is occurring today.

We recognize now that the sudden current global temperature's rapid increase is being artificially fueled by CO2 releases. 

And because greenhouse gases endure for many centuries, we face the prospect of CO2 further amplifying any eventual natural temperature increases that the Milankovitch effect does induce.
https://en.m.wikipedia.org/wiki/Carbon_cycle

Unlike the last interglacial that saw hippos basking in England, they'll someday be able to enjoy the fjords of Norway. Am I joking? Only time will tell. But, almost certainly Montana will some day be semi-tropical after ocean currents begin to shift. Am I joking? No, I'm quite serious. 
Climate change and ocean currents:
http://oceanexplorer.noaa.gov/facts/climate.html

Milankovitch Cycles:
https://skepticalscience.com/Milankovitch.html