Thursday, May 01, 2008

Ethon revs up the transport module

As you may recall, Eli has a bet with Stoat on 2008 setting a new record for minimum Arctic sea ice. A small birdie who munches adaptive liver out in Boulder has passed the word that the odds are shifting in the Rabett's favor.

New University of Colorado at Boulder calculations indicate the record low minimum extent of sea ice across the Arctic last September has a three-in-five chance of being shattered again in 2008 because of continued warming temperatures and a preponderance of younger, thinner ice.

The forecast by researchers at CU-Boulder's Colorado Center for Astrodynamics Research is based on satellite data and temperature records and indicates there is a 59 percent chance the annual minimum sea ice record will be broken this fall for the third time in five years. Arctic sea ice declined by roughly 10 percent in the past decade, culminating in a record 2007 minimum ice cover of 1.59 million square miles. That broke the 2005 record by 460,000 miles -- an area the size of Texas and California combined.

"The current Arctic ice cover is thinner and younger than at any previous time in our recorded history, and this sets the stage for rapid melt and a new record low," said Research Associate Sheldon Drobot, who leads CCAR's Arctic Regional Ice Forecasting System group in CU-Boulder's aerospace engineering sciences department. Overall, 63 percent of the Arctic ice cover is younger than average, and only 2 percent is older than average, according to Drobot.

The National Snow and Ice Data Center has an interesting map of the height of ice and snow above the sea surface from satellite measurements. This is roughly proportional to ice thickness.


William M. Connolley said...

Ha ha, keep whistling in the wind. I haven't noticed any upsurge in takers recently and the bet is still open.

Unknown said...

Eli Time you closed down I'm afraid. Hope you are able to keep going in any case. It was fun while it lasted LOL

Gareth said...

I still have it at 50/50, but it's nice to see some advice on the current form.

What am I up to at the moment? £20? Let's make that £30... (and a book, and a drink next time William's in Christchurch).

Anonymous said...

Those freeboard maps are impressive -- and depressing. Note that ICEsat carries a laser altimeter, meaning that the bounce comes from the top of the snow.

Assuming the ice and snow to be packed to density 0.9, gives the formula:
thickness = 10 x freeboard,
i.e., 1.5-2 m for most of the Arctic in 2007, and 1-1.5 m for 2008. In reality these are upper bounds.


Unknown said...

Your bet's looking better:

Anonymous said...

But Boys, the ice is still there. Cool summer coming, the world is not going to come to an end. Disheartening for some, I realise, but I know you'll come up with some other pending/potential/may-be-about-to-end-all-life-as-we-know-it disaster.

Your weather friends have the small swirly cloud patterns as hurricanes all sewn up, unfortunately shooting themselves in the foot by total 2007 NA hurricane energy, you know that index thingy the boffins measure, was at a real low. Talk about bummer.

Dano will find some beetle that has moved the wrong direction, or a flower that bloomed a day too early.

Not much, but the best you all can hope for.

Regards to all