5 ms·

This essay mentions the Younger Dryas but what it doesn't mention is that the Younger Dryas was a sudden return to glacial temperatures after the earth had alre

This essay mentions the Younger Dryas but what it doesn't mention is that the Younger Dryas was a sudden return to glacial temperatures after the earth had already warmed up at the end of the last glacial period. The magnitude of these swings in both directions are absolutely enormous and occur at much too rapid a speed to be attributable to trace greenhouse gas concentrations. Something else must have caused those swings. Either volcanic and geothermal activity or meteoric activity are the only likely culprits. https://en.m.wikipedia.org/wiki/Younger_Dryas https://en.m.wikipedia.org/wiki/Younger_Dryas There is evidence of Geothermal activity under the Antarctic ice sheet. Why is magma not on the table for glacial melting? See NASA article below: https://www.jpl.nasa.gov/news/news.php?feature=6996 https://www.jpl.nasa.gov/news/news.php?feature=6996 By the way the Antarctic ice sheet is currently at median levels (based on 1981-2010 baseline): https://nsidc.org/data/seaice_index/ https://nsidc.org/data/seaice_index/ The article also mentions 1m of sea level rise before 2100. There is no evidence of sea level rise acceleration. It is averaging 3.3 mm per year since 1993. Assuming there is not a cyclical downtrend in sea level (likely sometime this century, given grand solar minimum odds or chance of a major volcanic event), that would only amount to just under a foot per century of sea level rise. Source: https://climate.nasa.gov/vital-signs/sea-level/ https://climate.nasa.gov/vital-signs/sea-level/

bosswipe 6y ago
> Either volcanic and geothermal activity or meteoric activity are the only likely culprits. Another possibility is abrupt changes in the flow of large bodies of waters affecting ocean circulation causing climate changes. One hypotheses is as the glaciers retreated the waters of the Missisppi river switched to flowing out of the St Lawrence river affecting North Atlantic currents.
deleted 6y ago
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divbzero 6y ago
Why is it that the Antarctic ice sheet is currently at median levels while Arctic ice pack has changed so dramatically?
- roter 6y ago
  The southern hemisphere has not seen the same amount of polar "amplification" as the northern (b/c more land in the northern hemisphere). But still an active topic of research [0] [0] https://www.climate.gov/news-features/understanding-climate/understanding-climate-antarctic-sea-ice-extent https://www.climate.gov/news-features/understanding-climate/...
throwaway_pdp09 6y ago
> be attributable to trace greenhouse gas concentrations The use of the word 'trace' here seems to be weasel words. Doesn't matter if it's trace or not. Otherwise it's an interesting point. > There is no evidence of sea level rise acceleration As you back up all your other stats, why not this one. A bit of searching suggests you're wrong (multiple reputable sources are given in the article, from nasa + vims + noaa) "Of 32 tide-gauge stations in locations along the vast US coastline, 25 showed a clear acceleration in sea level rise last year" (and there's more there) https://www.theguardian.com/environment/2020/feb/03/sea-level-rise-accelerating-us-coastline-scientists-warn https://www.theguardian.com/environment/2020/feb/03/sea-leve... I'm getting tired of these posts. We're facing a threat to our very existence, facts matter.
roter 6y ago
> By the way the Antarctic ice sheet is currently at median levels (based on 1981-2010 baseline) Careful: ice sheet != sea ice. The formation of sea ice is strongly dependant upon underlying sea temperature & exposure to daytime sun & nightime radiational cooling. Ice sheets form on land due to snowfall. Most of the Antarctic sea-ice disappears every year in the southern hemisphere summer.

bosswipe 6y ago

> Either volcanic and geothermal activity or meteoric activity are the only likely culprits. Another possibility is abrupt changes in the flow of large bodies of waters affecting ocean circulation causing climate changes. One hypotheses is as the glaciers retreated the waters of the Missisppi river switched to flowing out of the St Lawrence river affecting North Atlantic currents.

deleted 6y ago

[deleted]

divbzero 6y ago

Why is it that the Antarctic ice sheet is currently at median levels while Arctic ice pack has changed so dramatically?

roter 6y ago
The southern hemisphere has not seen the same amount of polar "amplification" as the northern (b/c more land in the northern hemisphere). But still an active topic of research [0] [0] https://www.climate.gov/news-features/understanding-climate/understanding-climate-antarctic-sea-ice-extent https://www.climate.gov/news-features/understanding-climate/...

throwaway_pdp09 6y ago

> be attributable to trace greenhouse gas concentrations The use of the word 'trace' here seems to be weasel words. Doesn't matter if it's trace or not. Otherwise it's an interesting point. > There is no evidence of sea level rise acceleration As you back up all your other stats, why not this one. A bit of searching suggests you're wrong (multiple reputable sources are given in the article, from nasa + vims + noaa) "Of 32 tide-gauge stations in locations along the vast US coastline, 25 showed a clear acceleration in sea level rise last year" (and there's more there) https://www.theguardian.com/environment/2020/feb/03/sea-level-rise-accelerating-us-coastline-scientists-warn https://www.theguardian.com/environment/2020/feb/03/sea-leve... I'm getting tired of these posts. We're facing a threat to our very existence, facts matter.

roter 6y ago

> By the way the Antarctic ice sheet is currently at median levels (based on 1981-2010 baseline) Careful: ice sheet != sea ice. The formation of sea ice is strongly dependant upon underlying sea temperature & exposure to daytime sun & nightime radiational cooling. Ice sheets form on land due to snowfall. Most of the Antarctic sea-ice disappears every year in the southern hemisphere summer.