On the PIOMAS website the following is written:
The 2014 ice volume reached its annual maximum in April with 22,900 km3 which is just slightly below the long term trend and is the second lowest on record; just 400 km3 above the previous April minimum which occurred in 2011. However, variations over the last 4-years are well within the error bars of the volume estimates so that inter-annual variability over this period may be due to errors in the sea ice reanalysis.
Looking at the data I see that modelled volume reached 23,104 km3 on April 15th, which is slightly more than the 22,900 mentioned. Maybe the folks over at the PSC calculated the max differently.
Either way, it's the second lowest maximum in the PIOMAS record, more than 200 km3 below 2012 and 2013, and 427 km3 above 2011. At the end of April this has changed again (the Arctic cooled off slightly in the second half of April) with 2014 now in third spot, 658 km3 and 112 km3 above 2011 and 2013 respectively.
All of this is clearly visible on the PIOMAS graph produced by Wipneus (click for a larger version):
The anomaly trend line is still more or less in the same position relative to the linear trend line:
Interestingly enough average thickness is now virtually tied with 2012, probably because CT sea ice area numbers haven't decreased very fast. Remember, I crudely calculate ice thickness by dividing PIOMAS (PI) volume numbers with Cryosphere Today (CT) sea ice area numbers. This in itself doesn't say that much, could be off by a lot, but is interesting nonetheless as a comparison to previous years calculated in the same way:Here's average thickness for April 30th in metres, with change from last month between brackets:
- 2005: 2.16 (+0.18)
- 2006: 2.12 (+0.20)
- 2007: 2.01 (+0.14)
- 2008: 2.04 (+0.20)
- 2009: 2.03 (+0.19)
- 2010: 1.94 (+0.18)
- 2011: 1.90 (+0.20)
- 2012: 1.88 (+0.20)
- 2013: 1.90 (+0.21)
- 2014: 1.89 (+0.16)
If you want to have a look at the data yourself, you can download the spreadsheet I use and update from GoogleDrive.
The Polar Science Center thickness graph looks a lot different this month, with 2014 jutting out a lot more above the other post-2010 years. It has something to do with how they calculate average thickness, but I forgot the details:
Allow me to repeat what I wrote last month:
The recovery in volume seems to have disappeared due to a warm winter (see 2013/2014 Winter Analysis). A priori this would imply that the 2014 melting season could go every which way, as 'high' as 2013, or as low as 2012, depending on weather and distribution of volume across the ice pack.
It's all back to zero now. Could've been better, but could've been worse as well.