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Photo of the Chinese icebreaker Xue Long also beset in ice off East photographed from its own helicopter that evacuated 52 passengers from the Akademik Shokalskiy.

The Chinese icebreaker Xue Long (seen above) evacuated 52 passengers by helicopter from the research vessel Akademik Shokalskiy this week.

Photograph by Andrew Peacock, Aurora Photos

Marianne Lavelle

National Geographic

Published January 3, 2014

Drama continued to unfold Friday in the frozen sea around Antarctica as a Chinese ship that aided the trapped Russian vessel, M.V. Akademik Shokalskiy, found itself also stuck in the heavy ice. (Related: "Antarctic Ship Rescue: 5 Lessons From the Trapped-Vessel Drama.")

The struggles of the Chinese ship, Xue Long, or Snow Dragon, which had provided the helicopter used in the airlift rescue of 52 passengers aboard the Shokalskiy, raise new questions about icebreaking vessels and the limits of their capabilities.

The Australian Maritime Safety Authority (AMSA), which coordinated the rescue, said the Chinese ship was in no immediate danger but appeared to be trapped. The Australian icebreaker that is carrying the rescued passengers from the Russian ship, the Aurora Australis, was standing by to offer possible assistance, while officials assess whether changing conditions would free the ship. (Related: "Best Pictures From Dramatic Antarctic Ship Rescue.")

National Geographic talked to one of the leading experts on icebreaker technology, retired U.S. Coast Guard Rear Admiral Jeffrey M. Garrett, who served as the first commanding officer of the icebreaking cutter, the USCGC Healy, when it was delivered in 1999. Garrett served on a National Academies of Science committee in 2005 that urged that the United States invest in upgrading its icebreaking capability. (See "Arctic Shipping Soars, Led by Russia and Lured by Energy.")

Garrett spoke by telephone from Seattle, where he is now a private maritime affairs consultant.

What is an icebreaker?

It's a complicated question. There's a whole spectrum of ice capability for ships. There are ships with some extra hull protection and some extra protection for propellers and rudders that can go through very light ice, and it goes all the way up to strong and powerful ships that can go through just about anything. And there's not a real good terminology. It's like saying something is a "truck." Well, that can mean anything from a pickup to a huge semi. People ask, "What's an icebreaker like?" There are all kinds of them, and you've got to dig a lot deeper to know what it's capable of doing.

What about the Shokalskiy and the rescue ships in the Antarctic?

The Shokalskiy is an ice-capable ship, built in the Soviet era, and its main function is now expedition and tourism. The three ships that made attempts to reach it are all probably on the high end of the ice-capable scale, but I wouldn't classify them as icebreakers. (Also see: "Who's on That Russian Ship Stuck on Antarctic Ice?")

What's the metric that people use to tell the difference between an ice-capable ship and an icebreaker?

One of the rules of thumb is how many feet of ice could it break at a given speed. The U.S. has two of the most powerful non-nuclear icebreakers in the world, the Polar Sea and the Polar Star. They can break over 6 feet [1.8 meters] of ice continuously at [a speed of] three knots. [One of Russia's largest nuclear-powered icebreakers, considered the strongest in the world, could break] probably upwards of ten feet [three meters]. [A ship that is merely "ice-capable"] would break 3 feet [0.9 meter] of ice or less at that speed.

What is making conditions so hard for these ships in the Antarctic?

The toughest kind of ice is sea ice that's under pressure from wind. Ice has a rough texture, and wind will push an ice field close together and actually pile the ice up. I think this is essentially what happened to the Russian ship. The blizzard or heavy winds put the ice under pressure and jammed it up. (See your Antarctica photos.)

Aren't there forecasts or warnings that could help ships avoid such situations?

You can always 'Monday-morning quarterback' these things. Should they have gone in there? Well, clearly not, you can see now.

There is a lot of weather information available. The Antarctic, of course, [is] not as well covered. So sometimes forecasts are over such a wide area, you don't know how forecasts apply to localized areas. There's a lot of trash talk on the Internet about how they didn't look at the weather. But it's often tough to predict—especially in polar conditions, which can change quickly. You can always "Monday-morning quarterback" these things. Should they have gone in there? Well, clearly not, you can see now.  (See also: "Ship Stuck in Antarctica Raises Questions About Worth of Reenacting Expeditions.")

If Russia's nuclear icebreakers are so powerful, why wouldn't they be dispatched to help?

It's not like sending the AAA tow vehicle. It's a 20,000-mile [32,100-kilometer] journey. You're talking weeks and weeks. Also, the Russians are now in winter. Their icebreakers are all employed [in the Arctic]. We are in the Antarctic summer, so those ice conditions are probably going to get better. There's a very good chance the wind will die down or shift and they'll be able to get out.

Also, there's kind of an urban legend that Russian nuclear icebreakers can't go into warmer water because their cooling systems wouldn't be able to cool the nuclear reactors adequately. [Although we don't know if that's the case,] the Russians have never sent one of their nuclear [icebreakers] near the equator. Add to that the possible uproar about sending a nuclear ship into the pristine Antarctic, and it is not something the Russians are likely to do.

How different is an icebreaker from other vessels?

The question sometimes comes up of whether we can just retrofit existing ships—why don't we just put more steel in the hull and then it can go in ice?

But there's a significant difference in open-water vessels and ice-capable ships, and if you want an icebreaker it really must be built that way from the keel up.

You've got to protect things as mundane as the intakes where seawater comes in. [Intakes have to be screened] because ice can break into small pieces and enter the ship and clog the intakes.

You don't just take a normal ship's hull and make it into an icebreaker. The hull shape must be different. It has to have a bow that can crush ice, and the rest of the form has to be shaped in a way that it can go through ice efficiently. It's not just the size and thickness of the hull framing. It has to be very strong, but you also have to have all the ship systems strengthened so they can deal with cold weather: propellers, rudders.

What about power?

You have to have lots of horsepower and an ability to readily reverse and stop the direction of thrust quickly. The Polar-class ships have a very unique system, with two kinds of propulsion: a diesel-electric system for steaming over long distances, and gas turbines—like those on a commercial jet—that [provide extra power]. But the gas turbines burn a whole lot of fuel very fast. So the captain constantly has to make the decision on how much turbine power to use. [An icebreaker like the Polar Star would carry about 1.3 million gallons of diesel fuel aboard.]

How much does an icebreaker cost?

If you want something powerful, you are looking at almost $1 billion. You could probably design a more moderate ship that would meet most U.S. needs for something less, but you're talking about an expensive vessel.

Are we at the point where we need more ships with icebreaking capability, not just the U.S. but around the world?

The simplistic question you often get is, "With global warming, why do you need icebreakers?" But in the Arctic, you have more thinning and decrease in the ice pack, and that's making ice conditions more unpredictable. It's not like everything's getting easy. In some ways, global warming has increased the need for icebreaking and ice-capable vessels in both locations.

The Arctic is seeing a big increase in energy development and more shipping, and in the Antarctic you have more tourism. (Related interactive map: "The Changing Arctic.")

Now it appears that the Akademik Shokalskiy is not in immediate danger, but if a ship gets stuck and it gets dragged aground by the moving ice field, the hull could be punctured and this could have severe environmental consequences.

Follow Marianne Lavelle on Twitter.

Brian H.
Brian H.

With any luck, AGW is real. If we continue heading back to LIA conditions or worse, you won't like it. 
If we get back to Roman Warm Period ('Optimum') or better, it will be much nicer. 

Zord Lyng
Zord Lyng

btw, of course Climate Change is 'Real'. But Climate Change occurs even without man, so the AGW point is moot and to continue the argument shows their greed.. As I said CC disasters will occur regardless of mans contribution. We need not and cannot change the climate by changing our behaviour. What we can and must do is to change our behaviour to survive the evolving climate.

Zord Lyng
Zord Lyng

Freaking leave it to the Climate 'Zealots' to turn this into a climate debate. Stop proselytizing me with your scam.

Anthony Hills
Anthony Hills

I don't think there is much argument that there was global warming of about .5 deg C in the 30 yrs prior to 1998. 

The question has been what caused it. Man made Co2 has proven to be a minor factor that has not overcome the natural ocean cycle change in the Pacific. Also the cooling factors I mentioned in the previous post are hard to deny. 

The same thing happened 1945 to 1975 when Co2 was expanding rapidly in the post war expansion. Ocean cycles overcame the warming effect of Co2 . The 3 x forcing effect of cloud formation has been proven wrong by the climate itself and the clouds may actually be cooling instead.That is a complex subject that needs more research since the cooling Pacific may produce less clouds now.

There have been recent  factors like the ice recovery  this Winter and the greater amount of cold temperature records set last year compared to heat records. Climate scientists are not contesting the fact that the cooling Pacific PDO cycle has overcome the Co2 effect. This means that it also had strong warming effects starting in 1975 on top of 30 yrs of strong solar cycles. Sulphur dioxide emissions were greatly reduced during that time which let the sun in during that period which Asia is now reversing. One of the few warming factors left is the  Atlantic AMO cycle which is due to change to cool cycle in about 8 yrs. What are  the warming factors that will offset all of these cooling effects besides the proven to be very weak Co2? Carbon capture has proven to be prohibitively expensive and a threat to the world economy like in Europe where they supposedly spend 20% of their budget on climate change. I hear that 1.5 million people die there every year from the cold because they cannot afford the inflated energy prices to heat their homes. Hard to believe since one does not hear much about that in the media. It seems to be very elitist to say that we should drive energy prices to the moon as the President once suggested. I think he has changed his mind now that natural gas and oil fracking has been such a benefit to the economy and lower income people here? Industry is moving to the USA. Ironically natural gas has reduced Co2 emissions in the USA more than all the green energy efforts which amount to 1% of our energy mix. However I think  that we should continue to produce clean energy that makes economic sense like solar and perhaps wind but that does have issues with energy storage at non peak hours. Looking forward to the 49ers game but not sure how they will  fare at -13 deg and -30 windchill.

jim adams
jim adams

In spite of all the details everyone points to, the average temperature of the world has gone up significantly for the last 3 decades. So yes, there is a polar vortex coming down across the US and we have lower temperatures than we've had since 1998 (at least in my neck of the woods). Even with this cold snap figured in, the average temperature of the world measured in decades is still going up. And THAT is the real measure whether global warming is happening.

Arctic ice is at it's lowest level in the history of humanity .. and yes, it fluctuates. Some years there's less, and then it increases some, then it decreases more. The increase of sea ice however, is a one-year skim of ice, rather than a multi-year thick layer. The decade long pattern is for there to be less ice.  This is an unexpected "complication" (i'm being euphemistic here) of Arctic ice and permafrost melt. Wikipedia (Arctic Methane Release) says "not less than 1,400 Gt of Carbon is presently locked up as methane and methane hydrates under the Arctic submarine permafrost," A gigaton = 1 billion tons. Mathane is a greenhouse gas 20 - 25 times as active as CO2. Permafrost methane release is happening right now  tho we are still in the slow beginning stages.

And for Climate Deniers .. let me ask you: would you rather take actions NOW to shift this, or will you fight it until it is too late to make a difference -- i.e., once the methane starts coming out of the permafrost a little faster than it is now .. there will be nothing we can do. At that point we WILL get 15 to 20 feet of sea level (minimum) rise within several decades, world temperatures WILL increase much more rapidly, and several other equally important things. 

This .. as PlanetExtinction says, is the first really MAJOR tipping point in our relationship to Global Warming. A tipping point is where we would see a sign "Point of No Return". And .. something you should know: we can only know where tipping points are AFTER we've passed them. We can make good guesses, however. And tho the time from when we pass the tipping point to the time of a major tip -- may be a decade or several .. it will still be inevitable.

An example of a tipping point which a few have experienced: Imagine you are in a row boat, rowing down a river, your back to your future and facing your past. As you go downstream, you note a sign which says "point of no return" Nothing seems different so you ignore it. And you don't have to worry ----- for a while. You've got a quarter of a mile before the Niagara River turns vertical.

Anthony Hills
Anthony Hills

It seems reasonable to me that skeptics should think the way they do considering that they are told that global sea ice just hit a record high. Or that the Pacific Ocean has cooled owing to the PDO cycle. That Asia is pumping out huge amounts of cooling Sulphur Dioxide pollution. Or that there has been no warming for 12 to 17 yrs. That the Sun is in a cooler sunspot cycle. Co2 has proven to be less of a warming factor, admitted by the IPCC.  The climate models have been wrong. What happens when the Atlantic goes into the cooler AMO cycle in about 8 yrs? Is any of this not true? Do these things not count? I  don't see the need for name calling. 

James Simik
James Simik

I see there are still fools posting comments on here, global warming made the Arctic and Antarctic the hottest place on earth to explore, Oil, Gas Mineral, Fishing and the list goes on, Where once it was unthinkable to explore or extract oil/gas, it is now thinkable and yes the need is far greater for ice breakers

M Drummond
M Drummond

In some ways, global warming has increased the need for icebreaking and ice-capable vessels in both locations.


Mark Draskovich
Mark Draskovich

Yes. It is on the Great Lakes and smaller than the

Polar breakers or the Healy.

Eugene Whocares
Eugene Whocares

@M Drummond It's pretty simple really, the actual warming is barely perceptible, something less then a degree over the 20th century. The noticeable effects are those that stem from the tiny degree of warming... many weather effects depend on warm vs cold air interaction, adding more warm air intensifies the effects and that's what we're seeing (more severe hurricanes, tornadoes, typhoons, etc).

Some areas of our planet actually got colder over the same time frame. Global warming is a very complicated concept that involves a great number of systems that are not well understood. The fact that the "planetary" temperature went up a bit doesn't mean that every single place on the planet is now a jungle paradise.

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