Arctic sea ice bottoms out near all-time low; August was Earth's 4th - 8th warmest
Arctic sea ice extent hit its minimum on September 9 this year, falling to its second lowest value since satellite measurements began in 1979, according to the National Snow and Ice Data Center . More than one third (35%) of the Arctic sea ice was missing this summer, compared to the 1979 - 2000 average. This is an area about the size of the Mediterranean Sea. The 2011 sea ice minimum was very close to the all-time record low set in 2007; in fact, the University of Bremen rated the 2011 loss the greatest on record. For the fourth consecutive year, and fourth time in recorded history, ice-free navigation was possible in the Arctic along the coast of Canada (the Northwest Passage), and along the coast of Russia (the Northeast Passage.) Mariners have been attempting to sail these waters since 1497.
While the record low sea ice year of 2007 was marked by a very unusual 1-in-20 year combination of weather conditions that favored ice loss (including clearer skies, favorable wind patterns, and warm temperatures), 2011's weather patterns were much closer to average. The fact we pretty much tied the record for most sea ice loss this year despite this rather ordinary weather is a result of the fact that large amounts of thicker, multi-year ice has melted or been flushed out of the Arctic since 2007. As a result of the loss of this old, thick ice, both 2010 and now 2011 set new records for the lowest volume of sea ice in the Arctic, according the University of Washington PIOMAS model. Given the very thin ice now covering most of the Arctic, we can expect truly dramatic sea ice loss the next time 1-in-10 year or 1-in-20 year warmth and sunshine invades the Arctic. We are definitely on pace to see the Arctic virtually sea ice-free in summer by 2030, as predicted by several leading Arctic sea ice scientists. I expect we'll see more than half of the Arctic ice gone and the North Pole liquid instead of solid by the summer of 2020, and probably sooner.
Figure 1. Arctic sea ice extent in 2011 (blue line) compared to the record low year of 2007 (dashed green line) and average (thick grey line.) Image credit: National Snow and Ice Data Center .
When was the last time the Arctic was this ice-free?
We can be sure the Northwest Passage was never open for ice-free navigation--particularly ice-free navigation for multiple years in a row--between 1900 and 2000, as we have detailed ice edge records from ships (Walsh and Chapman, 2001). It is very unlikely the Passage was open between 1497 and 1900, since this spanned 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.
The Northwest passage may have been open multiple years in a row for ice-free navigation at some period during the Medieval Warm Period, between 1000 and 1300 AD. A better candidate was the period 6,000 - 8,500 years ago, when the Earth's orbital variations brought more sunlight to the Arctic in summer than at present. Funder and Kjaer (2007) found extensive systems of wave generated beach ridges along the North Greenland coast that suggested the Arctic Ocean was ice-free in the summer for over 1,000 years during that period. Prior to that, the next likely time was during the last inter-glacial period, 120,000 years ago. Arctic temperatures then were 2 - 3°C higher than present-day temperatures, and sea levels were 4-6 meters higher.
However, it is possible that the recent summer low-ice conditions in the Arctic are unprecedented for the past 800,000 years, according to a 2011 press release by Project CLAMER, a European group dedicated to climate change and European marine ecosystem research. They found that a tiny species of plankton called Neodenticula seminae that went extinct in the North Atlantic 800,000 years ago has become a resident of the Atlantic again, having drifted from the Pacific through the Arctic Ocean thanks to dramatically reduced polar ice. The 1999 discovery represents "the first evidence of a trans-Arctic migration in modern times" related to plankton, according to the UK-based Sir Alister Hardy Foundation for Ocean Science, whose researchers warn that "such a geographical shift could transform the biodiversity and functioning of the Arctic and North Atlantic marine ecosystems."
It is possible we'll have a better idea of historical ice-free conditions in the Arctic in the next few years. A new technique that examines organic compounds left behind in Arctic sediments by diatoms that live in sea ice give hope that a detailed record of sea ice extent extending back to the end of the Ice Age 12,000 years ago may be possible (Belt et al., 2007). The researchers are studying sediments along the Northwest Passage in hopes of being able to determine when the Passage was open during the past 12,000 years.
References
Belt, S.T., G. Masse, S.J. Rowland, M. Poulin, C. Michel, and B. LeBlanc, "A novel chemical fossil of palaeo sea ice: IP25", Organic Geochemistry, Volume 38, Issue 1, January 2007, Pages 16-27.
Funder, S. and K.H. Kjaer, 2007, "A sea-ice free Arctic Ocean?", Geophys. Res. Abstr. 9 (2007), p. 07815.
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.
August 2011: Earth's 4th - 8th warmest on record
August 2011 was the globe's 8th warmest August on record, according to the National Oceanic and Atmospheric Administration (NOAA) National Climatic Data Center (NCDC). NASA's Goddard Institute for Space Studies rated August the 4th warmest on record. Land temperatures during August were the 2nd warmest on record, and ocean temperatures were the 12th warmest on record. Ocean temperatures in the Atlantic Ocean's Main Development Region (MDR) for hurricanes, from the coast of Africa to the coast of Central America between 10°N and 20°N latitude, were 0.8°C above average, the 4rd warmest August on record. Global satellite-measured temperatures for the lowest 8 km of the atmosphere were the 6th or 3rd warmest in the 34-year record, according to Remote Sensing Systems and the University of Alabama Huntsville (UAH). For more details on global extremes during August, see the details from weather historian Christopher C. Burt.
Figure 2. Departure of temperature from average for August 2011. Image credit: National Climatic Data Center (NCDC).
Maria hits Newfoundland
Hurricane Maria hit Newfoundland, Canada yesterday afternoon near 3:30 pm local time as a Category 1 hurricane with 75 mph winds. However, the hurricane's strongest winds were over water, and the storm brought very little in the way of strong winds or heavy rain to the island. Cape Race at the southeast tip of Newfoundland saw sustained winds of 41 mph, gusting to 54 mph at 3:30 pm Friday as the center of the storm passed. Winds in the capital of St. John's peaked at 37 mph, gusting to 46 mph, at 10:30 am local time. Maria's strike makes this Newfoundland's second consecutive year with a hurricane strike, something that has never occurred since hurricane record keeping began in 1851. Last year, Hurricane Igor killed one person on Newfoundland, and damage exceeded $100 million, making Igor the most damaging tropical cyclone in Newfoundland history.
Figure 3. Satellite image of Hurricane Maria taken at 12:15 pm EDT September 16, 2011. At the time, Maria was a Category 1 hurricane with 75 mph winds. Image credit: NOAA Environmental Visualization Lab.
Invest 97L
For the first day since August 18, we don't have a named storm in the Atlantic. However, we have a new area to watch. A tropical wave that moved off the coast of Africa Friday and is now 300 miles south of the Cape Verde Islands is moving west at 10 - 15 mph. The wave has developed a modest amount of heavy thunderstorm activity and spin, and has been designated Invest 97L by NHC. Wind shear as diagnosed by the SHIPS model is light, 5 - 10 knots, and is predicted to stay light to moderate through Tuesday morning. Ocean temperatures are 27.5°C, one degree above the threshold typically needed for a tropical storm to spin up. Water vapor satellite images show 97L is embedded in a moist environment.
Most of the models develop 97L into a tropical depression by Tuesday; NHC gave the disturbance a 20% chance of developing into a tropical depression by Monday in their 2 pm Tropical Weather Outlook. 97L should head west or west-northwest towards the Lesser Antilles over the next six days, and could arrive in the islands as early as Friday--though most of the models predict a later arrival. It is likely 97L will encounter the usual troubles storms this year have had with wind shear and dry air on the long trek across the Atlantic.
I'll have a new post on Monday, when I'll discuss the long-range hurricane outlook for the rest of September.
Jeff Masters
Reader Comments
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 — Blog Index
I suspect we got somewhere around half an inch of rain here this afternoon, there some more stuff coming in from Central Texas on I-10 but I'm not sure if it'll survive by the time it ends up getting here.
Right now we have two vorticity maximums imbedded in the monsoon trough/ITCZ off the African coast around 10 north. The first area is elongated between 30-40W, while the second area is slightly more consolidated around 20W (97L). Although 97L is slightly more consolidated, it is also smaller than the vort max around 30-40W and has less convection coverage and intensity. A third area of interest will be moving into the area in around three days as a tropical wave pushes off the African continent.
Exactly what the models do with each one of these areas of potential development varies greatly between all the models. Based off this spread its pretty hard to make any reasonable predictions on what exactly will happen. With the vort max around 30-40W, we could either see slight development into a tropical depression or weak tropical storm, or just a failure to organize and intensify all together causing the area of vorticity to gradually dissipate. In all cases, however, models remain pretty firm on keeping the storm weak. The only exception is the 12z GFS which tries to make it into a hurricane, but this is definitely an outlier solution. With regards to 97L, the most likely solution appears to either have 97L die out or join with the tropical wave coming off the African coast in the next 3 days. As far as the tropical wave, most models are in pretty good agreement on eventual development with this wave which has been looking good for the last few days now. Of course, that doesn't guarantee anything, we'll still have to wait and see.
The biggest issue for these areas of interest will be some dry air in the environment and lackluster SSTs. Consolidation will also be a significant issue for the elongated area of vorticity around 30-40W. Wind shear and upper divergence may become inhibitors later down the road, but at the moment they aren't significant issues.
In any case, what the models do agree on is that we could see 1-2 more storms out of this region of the world in the next week from our 3 areas of interest. They also agree that any development in the region will be pretty slow and whatever storm results from this, will not be particularly intense (at least for the next week, none of the models are showing any hurricanes).
Funny? Seriously? :
There, but for the grace of God, go I.
Easy to be a comedian,this side of the fence.
Apologies.
nice!
Can you explain the logic behind using the average ice temperature from 1979 - 2000 and not some other time? Like why are we not comparing this year's ice to the average temperatures from 1979 - 2009? This would at least give us more points of data to average. While I recognize it is unique to have the Northwest passage open, I am confused at the arbitrary selection of data points for statistical comparison. I am just trying to understand here.
Thanks
Theresa 8-)
A BROAD AREA OF LOW PRESSURE HAS DEVELOPED OVER THE CENTRAL TROPICAL
ATLANTIC ABOUT MIDWAY BETWEEN THE LESSER ANTILLES AND AFRICA.
THUNDERSTORM ACTIVITY IS DISORGANIZED AND FURTHER DEVELOPMENT...IF
ANY...OF THIS LARGE DISTURBANCE SHOULD BE SLOW TO OCCUR AS IT MOVES
WESTWARD AT 10 TO 15 MPH. THIS SYSTEM HAS A LOW CHANCE...10
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.
Another yellow circle :)
Yellow all around.
Bout time for Mom Nature to rear her ugly head again. Activity is picking up across the basin, including the Caribbean. Something is going to pop soon.
why you lit into me earlier. He's my buddy.
The one I refer to will whine, call me a troll if he returns and tell you to put me on ignore.
Well it is September. XD
Most models agree that in 48hrs we should have two lows very close or at TD status.
Enjoying the lull in activity :-). Indeed September, ATL is priming.
Big storms like Irene & Maria tend to take hold of things if you know what I mean, their circulations were massive.
Correct to add Irene.
Agreed. Looks like the final push to the end of the season is here.
In no way that shows a Katia, similar track to Maria, yes, Katia, no.
Hard to imagine we are only one storm behind 2005 ATM.
Might end up one storm ahead/even soon at this rate.
Yeah, I started using it a few months after it came out and have preferred it every since. Firefox is good too but I just find that after it has been up for a while with a few tabs open it leaks like crazy. I have had a Firefox browser session consuming over 1gb of RAM within 12 hours of being opened.
Chrome is also nice in that it shows a chrome.exe process for each tab which means better memory management.
That I agree with.
Philippe (2005) weakened because of an ULL to its west, similar to where the ULL is now.
I think we'll see Philippe by the 27th.
I'm thinking we could see a late season boom, like last year.
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 PM EDT SAT SEP 17 2011
FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...
1. AN ELONGATED AREA OF LOW PRESSURE LOCATED A FEW HUNDRED MILES SOUTH AND OF THE CAPE VERDE ISLANDS (?what?) IS PRODUCING LIMITED SHOWER ACTIVITY.
HOWEVER...SOME SLOW DEVELOPMENT OF THIS SYSTEM IS POSSIBLE DURING
THE NEXT COUPLE OF DAYS AS IT MOVES WESTWARD AT 10 TO 15 MPH. THIS
SYSTEM HAS A LOW CHANCE...20 PERCENT...OF BECOMING A TROPICAL
CYCLONE DURING THE NEXT 48 HOURS.
2. A BROAD AREA OF LOW PRESSURE HAS DEVELOPED OVER THE CENTRAL TROPICAL
ATLANTIC ABOUT MIDWAY BETWEEN THE LESSER ANTILLES AND AFRICA.
THUNDERSTORM ACTIVITY IS DISORGANIZED AND FURTHER DEVELOPMENT...IF
ANY...OF THIS LARGE DISTURBANCE SHOULD BE SLOW TO OCCUR AS IT MOVES
WESTWARD AT 10 TO 15 MPH. THIS SYSTEM HAS A LOW CHANCE...10
PERCENT...OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.
LOL! Looks like Stewart had a little problem doing some copy/paste. XD
LOL...they forgot west XD
right? lol
ROFL!
AL, 97, 2011091800, , BEST, 0, 115N, 235W, 20, 1010, LO, 34, NEQ, 0, 0, 0, 0, 1012, 200, 75, 0, 0, L, 0, , 0, 0, INVEST, S,
You're not really rolling on the floor laughing, are you? You'll get dirty....
Something is bound to stir up sooner or later in the Caribbean. Just hope it remains weak also.
lol
the mb did go up one from 1009mb to 1010mb
-- Jeff Masters
Its been 1010 mb. since it was declared as an invest.
Viewing: 301 - 351
Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 — Blog Index