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: 597 - 547

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

597. NRAamy
2:01 PM PDT on October 12, 2007
I live in Southern California...Tahiti is closer...


:)
Member Since: January 24, 2007 Posts: 317 Comments: 31946
595. kmanislander
8:59 PM GMT on October 12, 2007
crystal clear warm water, white sand beaches, and the best fresh food

same here but a lot closer LOL
Member Since: August 19, 2006 Posts: 0 Comments: 15816
594. Soloco2
8:51 PM GMT on October 12, 2007
NRAamy........you're a lucky gal, indeed!
Member Since: Posts: Comments:
593. pablolopez26
8:57 PM GMT on October 12, 2007
588. NRAamy 8:57 PM GMT on October 12, 2007
it was the most beautiful place I have ever been...crystal clear warm water, white sand beaches, and the best fresh food...


Oh yeah well galveston beach is better, with our toilet bowl water, black sand, and glass in the water, and flesh eating ebola virus from Mars...
591. brazocane
3:56 PM CDT on October 12, 2007
Since the tropics are so slow, I have to admit it could not be a more beautiful day here in Houston. Just hope the fish are bitting tonight.
Member Since: Posts: Comments:
590. kmanislander
8:53 PM GMT on October 12, 2007
Hi everyone

just checking in for the day
It looks as if the low just offshore the N Belize border with Mexico is drifting slowly E

Here in the Caymans we have just been inundated with rain today. Inches and inches of it and still it continues.

Would sure like a break for the weekend but that low off Belize looks like a spoiler in the making

here's the vis loop. Link
Member Since: August 19, 2006 Posts: 0 Comments: 15816
589. NEwxguy
8:57 PM GMT on October 12, 2007
good night all
Member Since: Posts: Comments:
588. NRAamy
1:56 PM PDT on October 12, 2007
it was the most beautiful place I have ever been...crystal clear warm water, white sand beaches, and the best fresh food...
Member Since: January 24, 2007 Posts: 317 Comments: 31946
586. NRAamy
1:55 PM PDT on October 12, 2007


the resort....
Member Since: January 24, 2007 Posts: 317 Comments: 31946
585. NEwxguy
8:54 PM GMT on October 12, 2007
amy,those a incredible pics
Member Since: Posts: Comments:
584. Hhunter
8:51 PM GMT on October 12, 2007
jp i will add something to what you said. there may be some enhancement by industrial age but also consider urbinazation and how that affects temp readings. More importantly look at the data that we have in ice core samples going out 100,000's of years. Also just look at temp data over the last 70 years. Very hot in the 30,40,50's cooler if not colder in the 60-70's then hot again....just a microcosm of the bigger cycle. When the atlantic ocean cools down again in the next couple of years we will be having this debate about ice ages....
Member Since: August 19, 2007 Posts: 0 Comments: 2973
583. pablolopez26
8:53 PM GMT on October 12, 2007
My hut in Tahiti....

:)


Thats it, your banned!!! LOL
582. NRAamy
1:52 PM PDT on October 12, 2007



My hut in Tahiti....

:)
Member Since: January 24, 2007 Posts: 317 Comments: 31946
580. Hhunter
8:45 PM GMT on October 12, 2007
lickety split your going down a dangerous path again if you want to try and convenience me that gw is fact. let me say this much when it is claimed that temp are rising with corrupt data and improperply located temperature monintoring stations and computer models that project out 50 to 100 years when they are not even right 5 days out then you are drinking the cool aide my friend. If we would look at facts it would be helpful...loooooooooool
Member Since: August 19, 2007 Posts: 0 Comments: 2973
579. pablolopez26
8:45 PM GMT on October 12, 2007
pablo...that's where I stayed in Tahiti....

:)


You suck!!! :) Totally unfair and illegal, you should be banned forever from this site for actually having visited there... :)
578. seflagamma
4:45 PM AST on October 12, 2007
amy, I thought those looked familiar. I remember your pictures of your vac in Tahiti.


such a beautiful place.
Member Since: August 29, 2005 Posts: 298 Comments: 40902
577. NRAamy
1:43 PM PDT on October 12, 2007
pablo...that's where I stayed in Tahiti....

:)
Member Since: January 24, 2007 Posts: 317 Comments: 31946
576. seflagamma
4:43 PM AST on October 12, 2007
rofl!!!

never fear!
that time of year I am never on this blog; just come here during 'cane season for updates.. I'm on my own or the other blogs rest of the year. LOL

Member Since: August 29, 2005 Posts: 298 Comments: 40902
574. NEwxguy
8:42 PM GMT on October 12, 2007
573. seflagamma 8:41 PM GMT on October 12, 2007
LOL,,, I will be worse around Feb when you've had ice and freezes and are desperate for our balmy 85 degree sunshine! YOu like "fresh" tomatoes in January???? LOL!

your going on my ignore list for DEC,JAN,FEB
Member Since: Posts: Comments:
573. seflagamma
4:40 PM AST on October 12, 2007
LOL,,, I will be worse around Feb when you've had ice and freezes and are desperate for our balmy 85 degree sunshine! YOu like "fresh" tomatoes in January???? LOL!
Member Since: August 29, 2005 Posts: 298 Comments: 40902
572. NEwxguy
8:40 PM GMT on October 12, 2007
569. jphurricane2006 8:39 PM GMT on October 12, 2007
see youradjuster what is funny about your post is you know you will get reaction

due to your post and the reactions to it, you put is more off topic then we were if you had just left it alone, kind of contradicted your own post with that result

all im saying about it

I was thinking the same thing
Member Since: Posts: Comments:
571. NEwxguy
8:39 PM GMT on October 12, 2007
gamma,cruel,your just cruel!!!!
Member Since: Posts: Comments:
570. Hhunter
8:38 PM GMT on October 12, 2007
Kumbaya..sp....lol
Member Since: August 19, 2007 Posts: 0 Comments: 2973
568. lickitysplit
8:38 PM GMT on October 12, 2007
I dont understand why Global Warming is not, for some of the people on this blog, a relevent topic...for this blog. GW will bring massive changes to the whole world (it already is) and that will affect the tropics too. In a big way.

I suspect that, instead of wanting to have a serious, intelligent discussion on HOW GW will affect the tropical weather patterns, many here still want to debate IF it is even happening.

What would be interesting to me is to leave aside the discussion of IF (because its not even relevent given the weight of the evidence)and instead talk about the systems, the possible affects on thos systems and so on.
Member Since: Posts: Comments:
567. seflagamma
4:36 PM AST on October 12, 2007
NEwxguy... I'm sorry! LOL

I suppose you don't want to hear the pool temp is near 90 either do you??? or we go swimming on Christmas Day afternoon.. have a pool party on New Year's Eve???

LOL!!!

(please don't bann me this is weather we are talking about) LOL
Member Since: August 29, 2005 Posts: 298 Comments: 40902
566. pablolopez26
8:36 PM GMT on October 12, 2007


Ladies ladies, please can we all stop with the whole rules thingie... Sometimes we will have off topic discussions, geez... Now this from Tahiti... Enjoy...
565. Hhunter
8:35 PM GMT on October 12, 2007
JPhurricane, I agree with you it pains me to say. Topics that can be tied back into the tropics IE global warming are discussable as long as we can stay somewhat civil which i believe we had. That being said. I do believe 94L is a problem more for Texas and LA than florida..

Member Since: August 19, 2007 Posts: 0 Comments: 2973
564. GBlet
8:33 PM GMT on October 12, 2007
Oh by the way,most of the systems that roll across my area somehow affect either the gulf coast or the east coast! So i'm stayin and posting!
Member Since: Posts: Comments:
563. CatastrophicDL
8:30 PM GMT on October 12, 2007
Adjuster, Dr. M discussed the re-freezing of the Northwest Passage this morning and ice levels. That is about as far away from the tropics as you can get. So does that mean I can't discuss the three and a half hours of measurable snowfall I had here midday on the 29th of September? We divide our time between Florida, Texas, Utah and California. This year the climate and weather in every location has been very different. The different patterns we are seeing impact many places, including the tropics.
Member Since: Posts: Comments:
562. seflagamma
4:35 PM AST on October 12, 2007
are we "debating" again????
Member Since: August 29, 2005 Posts: 298 Comments: 40902
561. pablolopez26
8:28 PM GMT on October 12, 2007
By the way, i think Karen will remain a TS JP, i dont think they will reclasify... Seems to me top winds speeds on her reached 70mph... I stand to be corrected perhaps...
560. NEwxguy
8:35 PM GMT on October 12, 2007
557. seflagamma 8:33 PM GMT on October 12, 2007
Our Temps in the Ft Lauderdale area as of 4:30pm EDT:

88.2 °F / 31.2 °C
Partly Cloudy
Humidity: 59%
Dew Point: 72 °F / 22 °C
Wind: 2.0 mph / 3.2 km/h / 0.9 m/s from the ENE
Wind Gust: 10.0 mph / 16.1 km/h
Pressure: 29.73 in / 1006.7 hPa (Steady)
Heat Index: 95 °F / 35 °


see that "cool" front didn't make it this far! LOL


please don't post the weather conditions down there,from up here in the northeast,that really gets me down.
Member Since: Posts: Comments:
559. NEwxguy
8:32 PM GMT on October 12, 2007
555. youradjuster 8:31 PM GMT on October 12, 2007
Yes and I follow rules when they have been set. If there isn't anything happening in the tropics to speak of there will just be less posts but all posts WOULD BE about the tropics

Well,that sounds exciting
Member Since: Posts: Comments:
558. zoomiami
8:33 PM GMT on October 12, 2007
I guess trolls come in all sizes
Member Since: Posts: Comments:
557. seflagamma
4:31 PM AST on October 12, 2007
Our Temps in the Ft Lauderdale area as of 4:30pm EDT:

88.2 °F / 31.2 °C
Partly Cloudy
Humidity: 59%
Dew Point: 72 °F / 22 °C
Wind: 2.0 mph / 3.2 km/h / 0.9 m/s from the ENE
Wind Gust: 10.0 mph / 16.1 km/h
Pressure: 29.73 in / 1006.7 hPa (Steady)
Heat Index: 95 °F / 35 °


see that "cool" front didn't make it this far! LOL
Member Since: August 29, 2005 Posts: 298 Comments: 40902
556. GBlet
8:28 PM GMT on October 12, 2007
YA, i did not read ANYWHERE in your post that says this blog is restricted to the tropics only. I believe it says to STAY ON TOPIC.
Member Since: Posts: Comments:
555. youradjuster
8:28 PM GMT on October 12, 2007
Yes and I follow rules when they have been set. If there isn't anything happening in the tropics to speak of there will just be less posts but all posts WOULD BE about the tropics
Member Since: Posts: Comments:
553. cattlebaroness
8:24 PM GMT on October 12, 2007
Britches, you know long pants. Don't want any trouble. I intentionally keep my comments clean, just think the other ones in my head. Just kidding. I appreciate hearing about everyone's weather. Kind of reminds you how diverse our country is.

Speaking of diverse, while yall are looking at the ocean, I have to go feed goats and tend to an injured horse. Will look in on yall later.
Member Since: Posts: Comments:
552. seflagamma
4:28 PM AST on October 12, 2007
I still think there will be one more named system at least... happens all of the time in Oct and/or Nov.
Member Since: August 29, 2005 Posts: 298 Comments: 40902
551. seflagamma
4:27 PM AST on October 12, 2007
are you for real adjuster???
Member Since: August 29, 2005 Posts: 298 Comments: 40902
549. amazinwxman
8:26 PM GMT on October 12, 2007
Will anything come from the 1004 MB low off of Belize? It was mentioned in 2:05pm Discussion.
547. pablolopez26
8:23 PM GMT on October 12, 2007
so final numbers to me will say

16 storms, 6 hurricanes, 2 majors


Ill be serving your crow medium well... :) Your calling for 2 more "Named" storms and 2 of those becoming cat hurricanes... I dont know man... I dont see it happening right now...

Viewing: 597 - 547

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

Scattered Clouds
58 °F
Scattered Clouds