« Last post by Tor Bejnar on March 29, 2017, 11:55:59 PM »
...I say it does! The ice cap wasn't melting faster than it was expanding for a very long time, and now it is. (And what caused approximately 100% of this change, I'm sure, is AGW.)
The concept of "tipping point" does not apply to the Barnes ice cap.
What I attempted to communicate earlier is that changes in forces (e.g., CO2) within a system (e.g., the icy Arctic) affect different parts of the system (sea ice, ice caps) differently. Some things are like a canary in a coal mine - are affected obviously and quickly by certain changes - and others are not apparently affected. Ice caps are affected less than (or more slowly than) sea ice by AGW. (But a volcano erupting under an ice cap will melt more ice than a similar volcano erupting under the CAB.)
As to figuring out what non-AGW variability is affecting Arctic sea ice, there is "weather" - functionally good-for-melting seasons vs. good-for-keeping-ice-around seasons. The generic AGW conditions were similar, but the Arctic responses in 2007 and 2012 were very different from 2013 and 2014. If an 'average' season is half-way between these two pairs, what metric would one use to derive percentages (low points, high points, area, volume, some combination???)? My biggest problem with this approach is that weather patterns are changing because of AGW.