When the Arctic sea ice is gone

How long do you think it will take for most sea ice in the Arctic to disappear? How much change in temperature you think this would result in? 

Below an educated guess from a member of the Arctic Methane Emergency Group. 

Paul Beckwith

Paul Beckwith, B.Eng, M.Sc. (physics),
Ph.D. student (climatology) and
part-time professor, University of Ottawa

My projections for our planet conditions when the sea-ice has all vanished year round (PIOMAS graph projects about 2024 for this; I forecast 2020 for this) are:

• Average global temperature: 22 °C (+/- 1 °C)
  (rise of 6-8 °C above present day value of about 15 °C)
• Average equatorial temperature: 32 °C
  (rise of 2 °C above present day value of 30 °C)
• Average Arctic pole temperature: 10 °C
  (rise of 30 °C above present day value of -20 °C)
• Average Antarctica pole temperature: -46 °C
  (rise of 4 °C above present day value of -50 °C)
• Water vapor in atmosphere: higher by 50%
  (rise of 4% over last 30 years, i.e., about 1.33% rise per decade)
• Average temperature gradient from equator to North pole: 22 °C
  (decrease of 28 °C versus present day value of 50 °C)
• Very weak jet streams (driven by N-S humidity gradient and weak temperature gradient as opposed to existing large temperature gradient)

- Result: very fragmented, disjointed weather systems

- Basic weather: tropical rainforest like in some regions; arid deserts in others with few regions in between

Note: This scenario would require significant emissions of methane from the Arctic. Without this methane, the scenario would still occur but would take longer. Disclaimer: Best guess and subject to rolling revisions!

http://arctic-news.blogspot.com/2012/06/when-sea-ice-is-gone.html