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CPOM / UCL / ESA
CryoSat's detailed data have been used to generate this map of sea-ice thickness in the Arctic with data from January and February. Thanks to CryoSat's orbit, ice thickness close to the North Pole can be seen for the first time.
Scientists have long used satellite imagery to illustrate the shrinking extent of the Arctic sea ice. Now they've got satellite data that will provide regular updates on whether the ice is getting thinner as well.
The first ice thickness map from the European Space Agency's CryoSat spacecraft was released Tuesday at an air show in Paris. It was compiled with data collected in January and February.
The map shows, for example, the ice is thickest near the North Pole and off the coasts of Greenland and northeastern Canada. It thins as it stretches out towards Alaska and Russia.
Scientists expect the imagery to complement studies that show the Arctic sea ice extent is shrinking. This winter, for example, U.S. scientists reported the sea ice extent was among the smallest ever seen.
In recent years, scientists have consistently warned that the sea ice extent will shrink dramatically in the decades to come, primarily as a result of global climate change.
These warnings are based on models and observations of the sea ice extent — that is how much of the Arctic Ocean the ice covers. For a more robust understanding, scientists also need to know how thick the ice is.
The winds could, for example, push the ice out of one area but pile it up in another. This would mean the ice extent had diminished, but the volume remained the same.
CryoSat measures the thickness of the ice, providing a 3-D view, Walt Meier, a research scientist at the National Snow and Ice Data Center in Boulder, Colorado, told me today.
"Looking at the extent, we are just looking down at the surface, sort of the facade of the ice cover and you don't know exactly what it looks like underneath," he said. CryoSat, he added, will provide regularly updated pictures on the volume of sea ice.
Scientists have previously obtained ice thickness measurements, but only a few times a year with instruments such as NASA's IceSat, Meier noted. The new satellite provides continuous data. "It can show us how the ice changes seasonally and from year to year," he said.
The satellite obtains thickness measurements with a technique that bounces radar waves off the ice and the water in cracks which separate the ice floes. A calculation allows them to determine the sea ice thickness above the water.
Of course, about 90 percent of sea ice is actually underwater, "but if you measure the 10 percent above and know roughly what the density (of the ice) is, which tells you how much is above versus below, then you can calculate the total thickness," Meier said.
CPOM / UCL / ESA / Planetary Visions
For the first time, data from ESA's CryoSat mission have been used to map the height of the ice sheet that blankets Antarctica. CryoSat's ability to map the edges of the ice sheet is demonstrated by the detail that can be seen of the flow from east Antarctica onto the Ronne-Filchner ice shelf in the west. The outer white circle represents the limits of earlier missions and the inner circle shows that CryoSat is collecting data up 88° latitude.
For now, the thickness data shows the ice thickness in January and February. But in coming months more maps will be released and, over time, that allow scientists to see year-to-year changes in ice thickness.
"The data are exceptionally detailed and considerably better than the mission specification," the ESA writes in a news release. "They even show lineations in the central Arctic that reflect the ice's response to wind stress."
Meier cautioned, however, that the data is "fresh off the presses," more a proof of concept that the satellite can see sea ice and measure its thickness. "There are still a lot of things to work out ... it is too early to put a lot of stock in the absolute numbers."
In addition, the researchers have created a new map of Antarctica showing the height of the ice extent there. The data here is also preliminary, but shows CryoSat's ability to map the edges of the ice sheet in detail.
Understanding how ice sheets are changing at edges of Antarctica and Greenland is key, since change is happening fastest at the edges.
More on the Arctic sea ice:
- Arctic sea ice ties for smallest area this winter
- Arctic sea ice may be altering weather, expert says
- Inuit dog sleds help measure Arctic sea ice
- 2010 seeing hot temps, less Arctic sea ice
- Dramatic Arctic sea ice shrinkage predicted
John Roach is a contributing writer for msnbc.com. Connect with the Cosmic Log community by hitting the "like" button on the Cosmic Log Facebook page or following msnbc.com's science editor, Alan Boyle, on Twitter (@b0yle).
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"Is Artic ice thinning"?
With a rise in global temperatures, what else can we expect? Just the other day, there was another msnbc article on how oceanic species are quickly moving to mass extinction because of over-fishing and climate change. We can debate, bicker, get political but can't do much. Mankind's future on Earth does look bleak. Sigh.
The very least I can do is go plant a tree.
Over 95% of all species that have ever existed on this planet are now extinct, with most of them going extinct prior to mans rise as an intelligent species. This is just part of the natural cycle (yes, exacerbated by man with pollution but not enough to completely cause this) so this does not worry me. Just within the last week they announced a new solar minimum approaching that could cause another mini-ice age like that of the 17th and 18th centuries, so if that happens as predicted (and the sun has a far greater impact on the environment than any human) we could very well see the complete reversal of the ice shrinkage and in fact see glacial growth.
It's nature folks, can't fight it.
The Navy has been keeping records on ice thickness for quite a while. Data shows that ice is getting thicker in recent years. Here are some links that shows the Navy data and even how it matches up with the data referenced in this article. That's right. Thicker ice.
http://stevengoddard.wordpress.com/2011/03/18/growth-of-thick-ice-since-2008/
http://stevengoddard.wordpress.com/2011/06/21/cryosat-agrees-with-pips/
http://stevengoddard.wordpress.com/2011/02/08/arctic-ice-volume-has-increased-26-over-the-last-three-years/
And that doom and gloom ocean mass extinction article listed above has a lot of ties to Greenpeace and other leftist liberal so called environmental groups.
http://www.climate-resistance.org/2011/06/a-deep-sea-mystery.html
http://www.climate-resistance.org/2011/06/the-fishy-wishy-washy-ipso-report.html
@economykiller,
Steven Goddard, a reporter for "The Register", withdrew that contention in August 2008.
Econ: You want me to trust a couple of junk blogs over the Lawrence Livermore National Laboratories? (https://www.llnl.gov/news/newsreleases/2009/NR-09-06-05.html).
I don't think so!!!
Oh, I assumed economykiller was Steven Goddard himself. Why else would he get all of his disinformation from the same blogger?
Dear lord, quoting Steven Goddard?
What, did Donald Trump not comment on this story yet?
I don't know and I won't go check.
Economykiller, people with double digit IQ's should shut up until they understand the difference between opinions and facts.
Can the ships travel through or make their ways through?
Arctic’s ice cap floats. Its position at any given moment is at the
whim of the ocean conveyors, continental boundaries and prevailing winds. The melting of the Arctic ice will be from calories given up by the ocean and not the atmosphere. Since this ice pack, if you add in ALL the mountain glaciers' ice totals, amounts to LESS than ONE per cent of Earth’s total ice pack the effects, if melted at the end of the summer season in the northern hemisphere, will be local only. The ebb and flow of these ice packs (Arctic + all glaciers) are a result of a regional climate, not global.
If ALL the ice from the Arctic and glaciers melted at the end of the summer the effect upon sea level would be negligible, nearly impossible to ascertain since the oceans of the world are subservient to wind
fetches and tidal gyrations from a few feet to many tens of feet. However, there is evidence that this fresh
water melt, augmented by the Greenland melt, did overlay the cold Arctic salt waters to the point that it shut down the Gulf Stream (GS) for 10 days in 2004. This indicates that this regional climate is very fragile from a thermal observation.
No scientist knows what caused the GS to stop flowing in 2004. According to the Scientists at Woods Hole, the stoppage event was described as “the most abrupt change in the whole (climate) record”.
Greeland's ice pack makes up more than 8 per cent of Earth's total and Antarctica's pack contains more than 90% of the total.
The biggest problem with a shrinking Arctic is not so much sea level rise, but the positive feedbacks from a lower planetary albedo, and melting permafrost which releases methane (a far worse greenhouse gas), with the net effect of increasingly accelerating global warming. Then there are the terrible results from changing sensitive ocean ecosystems.
I'm no published scientist with a degree in anything, so my following views are just that, my views from my own personal research. You do your own to either validate or not the following information.
Depending on your point of view, you can/will collect data to support that view. VERY seldom will someone unbiasedly collect and report data as it stands on its on. That's just human nature. This is why you should take articles that support different views on a subject with a grain of salt. Concerning climate change, do your own independent study of whether the climate is getting warmer. Records exist of temperatures that go back a good number of years. Research that and average each year out from various places throughout the world and see where we stand now in relation to then. I did and found out that in a little over a 100 years, the temperature now as opposed to then, is on average 1 degree higher. However, I did no research in determining whether this change is/was due in part to our effecting the global environment or just a natural change not related to anything we have caused. One thing that I've observed personally is that when I was a teenage boy (40 years ago), we had noticeable seasons. I mean there was actually a noticed spring and fall. The last several years (where I live) it's went almost straight from winter into just about summer with hardly any spring in between. You don't need to be a scientist to know that something is causing this.
Analysis of climate "cause & effect" scenarios are a way we military-environmental-civil-engineers arrive at conclusions. Many scientists look for data to support their foregone conclusions.
Another significient component of the "natural" world climate is dust.
DUST: There is always a thin layer of dust circling the Earth in the upper reaches of the
atmosphere. Beautifully colored sunsets are clues, especially after a volcano
eruption. Thousands of tons of dust are blown off Earth’s deserts each year. Dust is one
of the regulators of Earth’s temperatures. Water vapors, which cannot occur in the atmosphere without dust
particles, are the main players in climate control. In fact every drop of participation, rain, snow or ice, must have a speck of dust around which to form. Without dust the humidity below 300% will not condense. Above 300% humidity water will condense on objects including humans.
Let’s look at the record storms of 2011 that occurred in the south and Midwest of the USA. The thousands of wild fires burning in the southwestern part of the USA produced many tons of dust into the atmosphere. This dust contributed to the volatility of these storms. No weather model used in forecasting nor did the meteorologist presenting these forecast mention in their interpretation of conditions the possible quantity impact that dust, as an input, from these wild fires had any effect upon what was happening weather wise.
Without dust from the Sahara Desert the Atlantic hurricane season would not exist. The Caribbean Islands
would consist of grey rock without dust from the Sahara, which produced the Island’s layers of top soil.
Dust may turn out to be the most important thermal climate regulator of all the culprits that science has assigned that roll.
Everything on Earth, alive or not, is in a constant state of entropy, thus turning into dust. The millions of tons released into the atmosphere each year have an enormous effect upon Earth climates, from participation to becoming filament to absorb and retain calories/heat.
Read: Holmes, Hannah, “The Secret Life of Dust”, John Wiley & Sons, 2001
Science needs to determine the "cause & effects" of Nature not of the "world" that we have created!
FairTax Fan wrote: "...This is just part of the natural cycle (yes, exacerbated by man with pollution but not enough to completely cause this) so this does not worry me. Just within the last week they announced a new solar minimum approaching that could cause another mini-ice age..."
You are obviously NOT a scientist. I am. This is NOT a part of a natural cycle and NO serious scientist I know claims it is. Even the poster-boy scientist of the anti-Global Warming movement, Mojib Latif recently said on National Public Radio, "My middle name is Global Warming: of course I believe in it." The smoking gun is the joint U.S.-French-Russian Vostok study of air bubbles trapped in Antarctic Ice shows max. CO2 of 294 ppm over the last 420,000 years. Spot-checks show the same for 21,000,000 years. It's 385 ppm right NOW. Tell us how that is "cyclical"? Or don't you need to be confused by the FACTS since you know it all?
And who are "they" who say a solar minimum could cause another ice age? And WHEN? You a great example of how a little bit of information can lead someone to make huge errors if they assume they know enough to form valid conclusions.