Fabled Northwest Passage begins to re-freeze

By: Dr. Jeff Masters , 2:29 PM GMT on October 12, 2007

Share this Blog
3
+

This summer's dramatic loss of Arctic sea ice peaked on September 15, and the polar ice cap is finally beginning to re-freeze, according to a press release issued by the National Snow and Ice Data Center on October 1. Extent of the September polar sea ice fell 39%, compared to the 1979-2000 average. To put this loss in perspective, in one year we lost as much ice as we lost during the previous 28 years. Summertime Arctic sea ice is now at 50% of what it was in the 1950s (Figure 1). One may look at at graph and wonder, but what about sea ice loss in other seasons? It hasn't been nearly so severe. True, but it is the summer ice we care most about, since summer is when the thick, multi-year ice melts, which can then precondition the Arctic for much greater ice loss in future years. As sea ice melts in response to rising temperatures, more of the dark ocean is exposed, allowing it to absorb more of the sun's energy. This further increases air temperatures, ocean temperatures, and ice melt in a process know as the "ice-albedo feedback" (albedo means how much sunlight a surface reflects). There is an excellent chance that the summer of 2007 will be remembered as the "tipping point" for Arctic sea ice, when an irreversible ice-albedo feedback process firmly established itself.



Figure 1. Arctic sea ice extent since 1900, as estimated from satellite and ship reports compiled by Walsh and Chapman (2001). Image credit: University of Illinois cryosphere group.

Northwest Passage opens for the first time in recorded history
Long before the Panama and Suez Canals made commercial trading between the Atlantic and Pacific Oceans economically feasible, ships made the long and perilous trip around the African and South America continents. Explorers, traders, and world leaders looking for faster and less dangerous shipping routes to far-away areas of the world have long eyed two routes through the ice-choked Arctic Ocean--the fabled Northwest Passage, through the cold Arctic waters north of Canada, and the Northeast Passage, extending along the northern coast of Russia. The first recorded attempt to find and sail the Northwest Passage was in 1497, and ended in failure. The thick ice choking the waterways thwarted all attempts at passage for the next four centuries. Finally, in 1905, Roald Amundsen completed the first successful navigation of the Northwest Passage. It took his ship two-and-a-half years to navigate through narrow passages of open water, and his ship spent two cold, dark winters locked in the ice during the feat. More recently, icebreakers and ice-strengthened ships have on occasion battered their way through the ice-blocked route.



Figure 2. The Northwest Passage shipping route (red line) and Northeast Passage (green line) superimposed on an ice coverage map from August 22, 2007. The Northwest Passage was ice-free and navigable for 36 days between August 14 and September 18, 2007. The Northeast Passage was blocked by a narrow strip of ice most of the summer. Image credit: National Snow and Ice Data Center.

Times are changing. In 2001, the Bering Strait, a key portion of both the Northwest and Northeast Passages, was completely ice free. This was followed in 2005 by record-breaking sea-ice melt in the Arctic, leading to the first ever recorded opening of the Northeast Passage. The fabled Northwest Passage remained closed in 2005. Arctic ice recovered a bit in 2006, and both passages remained closed. But the unprecedented melting during the summer of 2007 saw the Northwest Passage become ice-free and navigable along its entire length without the need for an icebreaker as of August 14, 2007. Remarkably, the Northwest Passage remained ice-free for 36 days, finally refreezing over a small section on September 19. The Northeast Passage was blocked by a narrow strip of ice all summer. However, this strip of ice thinned to just 30% coverage on September 25 and 26, making the Northeast Passage passable for ordinary ships on those days.

When is the last time the Northwest Passage was open?
We can be sure the Northwest Passage was never open from 1900 on, as we have detailed ice edge records from ships. It is very unlikely the Passage was open between 1497 and 1900, since this was a cold period in the northern latitudes known as "The Little Ice Age". Ships periodically attempted the Passage and were foiled during this period, and the native Inuit people have no historical tales of the Passage being navigable at any time in the past.

A good candidate for the last previous opening of the Northwest Passage was the period 5,000-7,000 years ago, when the Earth's orbital variations brought more sunlight to the Arctic in summer than at present. Prior to that, the Passage was probably open during the last inter-glacial period, 120,000 years ago. Temperatures then were 2-3 degrees Centigrade higher than present-day temperatures, and sea levels were 4-6 meters higher.

Final thoughts
If we have reached the tipping point for Arctic ice, what are the implications? I'll discuss this more in a future blog. Sea ice is very complicated, and it is not a sure thing that we have reached the tipping point. For more on the complexities of sea ice, read wunderblogger Dr. Ricky Rood's latest blog.

NASA has posted a beautiful satellite image of the Arctic ice cap at the September 15 2007 minimum, showing the open water of the Northwest Passage.

I thank Edalin Michael of the University of Michigan's School of Natural Resources and Robert Grumbine of NOAA's Sea Ice Group for their contributions to this blog.

References
Walsh, J.E and W.L.Chapman, 2001, "Twentieth-century sea ice variations from observational data", Annals of Glaciology, 33, Number 1, January 2001 , pp. 444-448.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 497 - 447

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24Blog Index

497. IKE
2:58 PM CDT on October 12, 2007
Here is the 12Z ECMWF and sure nuff...it is in line with the GFS 12Z run....

Link


The 12Z CMC is about the same.
Member Since: Posts: Comments:
496. Hhunter
7:56 PM GMT on October 12, 2007
lake shadow it's not that you riled people it is that you have drank from the algore global warming cool aide a little to much.. That is ok it is a free country and debate is healthy.
Member Since: Posts: Comments:
494. Floodman
7:56 PM GMT on October 12, 2007
487. hurricanehanna 7:55 PM GMT on October 12, 2007
Baroness, I think your picture is very pretty.
Don't put a cow up there.




Agreed...no bovines unless it really is a pic of you...
Member Since: August 2, 2006 Posts: 10 Comments: 9922
492. plywoodstatenative
3:55 PM EDT on October 12, 2007
I think our new low may have something else to interact with before the wave gets to it. Take a look at the rainbow loop southeast of Cuba. Something spinning down there that just might influence development and help the wave out once it gets along that axis. Also have a small spin off the coast of Florida. What it is I can't tell.
Member Since: Posts: Comments:
491. aubiesgirl
7:55 PM GMT on October 12, 2007
aubiesgirl 2:50 PM CDT on October 12, 2007
Ike are we still under red flag conditions?

Yes...

Statement as of 3:11 PM EDT on October 12, 2007

... A red flag warning remains in effect until 7 PM EDT/6 PM CDT
this evening for all of the Florida Big Bend and Panhandle areas due
to long durations of relative humidity below 35 percent...

... Red flag warning remains in effect until 7 PM EDT /6 PM CDT/
this evening...
... Red flag warning in effect from 2 PM EDT /1 PM CDT/ to 6 PM
EDT /5 PM CDT/ Saturday...

A red flag warning means that critical fire weather conditions
are either occurring now... or will shortly. The low relative
humidity will enhance fire growth potential.

well lol..no pit fire tonight...lol...I love the low humidty though..been great!!..so keep 94L away..lol
Member Since: Posts: Comments:
490. FLSWEDE
7:54 PM GMT on October 12, 2007
The 12Z model run of ECMWF shows the same low runing up the GOM and heading to the Big Ben area as the 12Z GFS did.
Member Since: Posts: Comments:
489. Floodman
7:54 PM GMT on October 12, 2007
481. hurricanehanna 7:52 PM GMT on October 12, 2007
Thanks Floodman. And some people say it's over.....



Only the trolls, dude, only the trolls
Member Since: August 2, 2006 Posts: 10 Comments: 9922
488. IKE
2:54 PM CDT on October 12, 2007
aubiesgirl 2:50 PM CDT on October 12, 2007
Ike are we still under red flag conditions?


Yes...

Statement as of 3:11 PM EDT on October 12, 2007

... A red flag warning remains in effect until 7 PM EDT/6 PM CDT
this evening for all of the Florida Big Bend and Panhandle areas due
to long durations of relative humidity below 35 percent...

... Red flag warning remains in effect until 7 PM EDT /6 PM CDT/
this evening...
... Red flag warning in effect from 2 PM EDT /1 PM CDT/ to 6 PM
EDT /5 PM CDT/ Saturday...

A red flag warning means that critical fire weather conditions
are either occurring now... or will shortly. The low relative
humidity will enhance fire growth potential.
Member Since: Posts: Comments:
487. hurricanehanna
2:54 PM CDT on October 12, 2007
Baroness, I think your picture is very pretty.
Don't put a cow up there.
Member Since: Posts: Comments:
485. ihave27windows
2:52 PM CDT on October 12, 2007
Imagine how boring this blog would be without the occasional cute troll.....

SE. Texas is beautiful, and I refuse to believe anything with a name will be in the GOM....at least not until next June. lol
Member Since: Posts: Comments:
484. Floodman
7:54 PM GMT on October 12, 2007
"...cure little trolls..."

LOL
Member Since: August 2, 2006 Posts: 10 Comments: 9922
483. DallasGumby
7:50 PM GMT on October 12, 2007
472. NEwxguy 7:48 PM GMT on October 12, 2007
((((sigh))) give it a rest,it really comes out like whinning


Is "whinning" a point half way between winning and whining?

LOL!

Member Since: Posts: Comments:
482. NotAnotherHURRICANE
7:50 PM GMT on October 12, 2007
Hope it doesn't rain tomorrow in Miami. Been waiting a lobgtime to see the Miami Hurricanes vs. Georgia Tech. Hopefully this year we have an answer for them. GO CANES!!!
Member Since: Posts: Comments:
481. hurricanehanna
2:49 PM CDT on October 12, 2007
Thanks Floodman. And some people say it's over.....
Member Since: Posts: Comments:
480. Floodman
7:48 PM GMT on October 12, 2007
471. IKE 7:47 PM GMT on October 12, 2007
hurricanehanna 2:44 PM CDT on October 12, 2007
Afternoon, man, this blog gets pretty interesting sometimes. Hey JP, or Aubie, or Flood or Ike -
what is going on with old 94L? Is it back over the water?

It's right at the coast...click NCEP fronts...



Ike, I think 94L is spinning SW of the low on the coast...inland, just south of the Mexican border...
Member Since: August 2, 2006 Posts: 10 Comments: 9922
479. cattlebaroness
7:46 PM GMT on October 12, 2007
I am sitting here dying laughing. I think I will change mine to one of my cows. Also JP are you suggesting we are all old (sort of) and ugly. That hurts. By the way, love led zep and jerry garcia...mine would have been somewhere along the lines of Seals and Crofts, Joan Baez, Joanie Mitchell, etc.

Back to tropics, before I am ignored by everyone. So maybe by Monday we will have a named system in the GOM? that would certainly heat up this blog and keep those cute little trolls away.
Member Since: Posts: Comments:
478. aubiesgirl
7:49 PM GMT on October 12, 2007
Ike are we still under red flag conditions?
Member Since: Posts: Comments:
477. weathers4me
7:46 PM GMT on October 12, 2007
What is an avaitar?? Is it something like a chupacabre??
Member Since: Posts: Comments:
476. pablolopez26
7:47 PM GMT on October 12, 2007
I guess all people that post on a weatherblog are either fat, ugly or look like a nerd

guess no attractive people can post here lol


Nope im not saying that either, all what im saying is, they are doing it for another purpose... Go back and review what she posted in regards to the weather and all... Come on JP, wake up...
475. hurricanehanna
2:48 PM CDT on October 12, 2007
Thanks Ike. So, what is it supposed to do when it jumps in the water?
Member Since: Posts: Comments:
474. IKE
2:47 PM CDT on October 12, 2007
cattlebaroness 2:46 PM CDT on October 12, 2007
NEwx, I saw one of the links that showed 2 lows over Yuc., 2 systems? Also IKE would that increase in precip for TX be related to a possible system moving into the GOM?


That 6-10 day outlook calls for below normal over the "lone-star" state....it's above normal east of there.
Member Since: Posts: Comments:
473. Floodman
7:46 PM GMT on October 12, 2007
465. hurricanehanna 7:44 PM GMT on October 12, 2007
Afternoon, man, this blog gets pretty interesting sometimes. Hey JP, or Aubie, or Flood or Ike -
what is going on with old 94L? Is it back over the water?



It, or somethinglike it, is sitting over Gautemala...there's another feature half on and half off the coast, testing the water in the Carib...
Member Since: August 2, 2006 Posts: 10 Comments: 9922
471. IKE
2:45 PM CDT on October 12, 2007
hurricanehanna 2:44 PM CDT on October 12, 2007
Afternoon, man, this blog gets pretty interesting sometimes. Hey JP, or Aubie, or Flood or Ike -
what is going on with old 94L? Is it back over the water?


It's right at the coast...click NCEP fronts...

Link
Member Since: Posts: Comments:
469. cattlebaroness
7:43 PM GMT on October 12, 2007
NEwx, I saw one of the links that showed 2 lows over Yuc., 2 systems? Also IKE would that increase in precip for TX be related to a possible system moving into the GOM?
Member Since: Posts: Comments:
468. Floodman
7:43 PM GMT on October 12, 2007
Sorry, off topic, but I am rolling on the floor. I love watching this blog for the great tropics info. Love the links to the great graphics (which I normally don't understand), but I am surprised at the majority of you folks who do not realize anyone can post any picture on their avaitar or whatever. Maybe I should shop for one also.



No, really baroness...I AM the cartoon caricature of Jerry Garcia...LOL
Member Since: August 2, 2006 Posts: 10 Comments: 9922
465. hurricanehanna
2:40 PM CDT on October 12, 2007
Afternoon, man, this blog gets pretty interesting sometimes. Hey JP, or Aubie, or Flood or Ike -
what is going on with old 94L? Is it back over the water?
Member Since: Posts: Comments:
464. IKE
2:42 PM CDT on October 12, 2007
cattlebaroness 2:42 PM CDT on October 12, 2007
Sorry, off topic, but I am rolling on the floor. I love watching this blog for the great tropics info. Love the links to the great graphics (which I normally don't understand), but I am surprised at the majority of you folks who do not realize anyone can post any picture on their avaitar or whatever. Maybe I should shop for one also.


Mines legit....Plant, Page, Jones and Bonham...aka...Led Zeppelin! They did and still do exist.

EDIT>>> Except for John Bonham...RIP.
Member Since: Posts: Comments:
463. NEwxguy
7:42 PM GMT on October 12, 2007
454. tampabayfish 7:39 PM GMT on October 12, 2007
Alright, everyone have a great weekend! Sox in 5! Pats by 14! ...And I'm out!

lol,now thats an exit
Member Since: Posts: Comments:
461. NEwxguy
7:41 PM GMT on October 12, 2007
449. cattlebaroness 7:34 PM GMT on October 12, 2007
NEwx, Thanks. I am a little behind in looking at the sat., is 94 back over water?

Not yet,but some models are saying it will reenter the carribean,opinions are split on what it does from there.
Member Since: Posts: Comments:
460. DallasGumby
7:34 PM GMT on October 12, 2007
362. tampabayfish 6:55 PM GMT on October 12, 2007
NE... Its game time, beer thirty, . . . Brady for 400 and 4 TD's... Oh its gonna be a good weekend!


I can't resist.

Give it a rest, you Pats fans. You're not playing the Jets this weekend, a team about which you have hours of videotape of the defensive coaches giving the defensive signals.

LOL!!!

I can't wait for Sunday. If the 'Boys lose, it's no big deal, the media says they're supposed to lose anyways, and they're still in first in the best division in football. If the 'Boys win, the shock coming from the northeast will be priceless.

And, believe it or not, this post is about the weather. Kickoff at 3:15 Sunday, it's supposed to be sunny with temps in the mid-80s.
Member Since: Posts: Comments:
459. cattlebaroness
7:34 PM GMT on October 12, 2007
Sorry, off topic, but I am rolling on the floor. I love watching this blog for the great tropics info. Love the links to the great graphics (which I normally don't understand), but I am surprised at the majority of you folks who do not realize anyone can post any picture on their avaitar or whatever. Maybe I should shop for one also.

Back to weather, gamma, what is considered cool weather in Fl? I am in TX and the days are still hot, but evenings are hitting low 60's, high 50's. Feels like fall.
Member Since: Posts: Comments:
458. IKE
2:39 PM CDT on October 12, 2007
6-10 day outlook...

Link

Above normal rain for the extreme eastern USA...94L?

Member Since: Posts: Comments:
457. pablolopez26
7:40 PM GMT on October 12, 2007
I say Indians in 5!!!! Go Tribe!!! Josh Beckett vs Sabathia!! Wow!!!
455. groundswell
7:38 PM GMT on October 12, 2007
AS HIGH SETTLES SOUTHWARD OVER THE CAROLINAS...LIGHTER WINDS WILL BE IN STORE (early in the weekend) OVER THE WATERS WITH SPEEDS GENERALLY AROUND 10 KNOTS. GRADIENT TIGHTENS ONCE AGAIN NEXT WEEK WITH NAM12 INDICATING POSSIBLE SCA CONDITIONS (by late in the weekend). WILL BLEND FOR NOW WITH THE LESS AGGRESSIVE GFS WHICH RESULTS IN GENERAL 15 TO 20 KNOT (onshore) FLOW over the offshore waters late weekend into early next week).

rideable windswell on Sunday.
Member Since: Posts: Comments:
454. tampabayfish
7:39 PM GMT on October 12, 2007
Alright, everyone have a great weekend! Sox in 5! Pats by 14! ...And I'm out!
Member Since: Posts: Comments:
453. Floodman
7:38 PM GMT on October 12, 2007
431. LakeShadow 7:28 PM GMT on October 12, 2007
yeah, jp but the rush limbaugh comment didnt go over very well...
my bad. Its just soooo recited. like being 16yrs again and listening to my parents' lecture #368
you know?


Rush Limbaugh?!?! Slowly I turned...step by step...

Member Since: August 2, 2006 Posts: 10 Comments: 9922
449. cattlebaroness
7:30 PM GMT on October 12, 2007
NEwx, Thanks. I am a little behind in looking at the sat., is 94 back over water?
Member Since: Posts: Comments:
447. weathers4me
7:30 PM GMT on October 12, 2007
Hows it goin gang? Anything brewing? I see we got diverted a bit earlier. Focus people. Lord knows some of these pics doesn't make it easy with a bunch of weather guys (and gals) LOL. Looks like a nice weekend weather wise for the SE. Have a good one.
Member Since: Posts: Comments:

Viewing: 497 - 447

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24Blog Index

Top of Page

About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.

Local Weather

Overcast
29 °F
Overcast