Why Third Year Arctic Ice Will Increase Next Year

2. At the other pole, NSIDC released an interesting statistic that Arctic ice "older than two years" reached a record low this winter.

So what happened to the three year old ice in 2009? The answer is simple. During the summer of 2007, almost all of the 1st year ice melted. Because of this, there was very little 2nd year ice in 2008, and 3rd year ice in 2009. The amount of second year ice in 2008 had to be less than or equal to the amount of first year ice at the end of the 2007 summer. Even if we had entered an ice age in 2008, there would not be much third year ice in 2009.

However, note in the NSIDC graph above that the amount of 2nd year ice (orange) approximately tripled in 2009 relative to 2008, from about 3% to 10%. The implication being that (barring a radical change in Arctic conditions) the amount of 3rd year ice will likely expand significantly in extent in 2010. Perhaps even triple in extent. Simply because the "terrible two" year old ice will be one year older. The red-brown portion of the graph should increase in height next year, as the 2nd year ice becomes more than 2 years old. The top of the orange should also move up significantly, as the red-brown region below it pushes it up.

No wonder people are pushing so hard for "climate legislation" in 2009. Graphs like the one below don't look very scary, with global sea ice area 683,000 km2 above normal, and Catlin reporting wicked cold - day after day.