This is Conrad Dunkerson's Typepad Profile.
Join Typepad and start following Conrad Dunkerson's activity
Join Now!
Already a member? Sign In
Conrad Dunkerson
Recent Activity
There are a few statements above to the effect that area must always be less than extent. While this is historically accurate it is not necessarily so from a mathematical viewpoint. Every year there is a portion of the ice pack below 15% concentration which is effectively treated as zero extent, but non-zero area. Thus, considering only that portion of the ice pack, area is greater than extent. Whether we will ever see a year in which a significant enough portion of the pack is at less than 15% concentration that the total area exceeds extent is an open question. I'd have said it couldn't happen, but this year is showing that it IS possible for large portions of the pack to exist as 'slush' with an effective extent of zero. Note that this also means the 'CAPIE' figures are in a sense overstated. If extent were calculated on >0% sea ice instead of >=15% sea ice the extent values would be larger and the CAPIE values correspondingly lower. However, since every identifiable speck of ice counts for area, but only >=15% counts for extent there is a degree of inspecificity in the factor. That is, identical CAPIE values can be reached for different ice concentration amounts. This divergence is probably very small... except in years like the current where there is a significant amount of <15% concentrated sea ice.
Toggle Commented Aug 15, 2011 on CAPIE hits record low at Arctic Sea Ice
Conrad Dunkerson is now following The Typepad Team
Aug 15, 2011