Arctic Sea Ice Melts More Each Year

Posted September 7th, 2012 at 10:38 pm (UTC-4)

This visualization shows the extent of Arctic sea ice on Aug. 26, 2012, the day the sea ice dipped to its smallest extent ever recorded in more than three decades of satellite measurements, according to scientists from NASA and the National Snow and Ice Data Center. (Image: NASA)

This graphic shows the extent of Arctic sea ice on Aug. 26, 2012, the day the sea ice dipped to its smallest extent in more than three decades of satellite measurements, according to scientists from NASA and the National Snow and Ice Data Center. (Image: NASA)

The Arctic sea ice cover has melted to its lowest extent since satellite observations of it began more than three decades ago, breaking a previous record low set in 2007.

NASA and scientists at the University of Colorado, Boulder report the Arctic sea ice extent  –  the amount of ice covering the sea surface – fell to 4.10 million square kilometers in Aug. 26, 2012.  And, with more days left in the summer melting cycle, they anticipate even more of a loss before the freeze cycle begins at the end of September.

“By itself it’s just a number, and occasionally records are going to get set. But in the context of what’s happened in the last several years and throughout the satellite record, it’s an indication that the Arctic sea ice cover is fundamentally changing,” said Walt Meier, a scientist at the National Snow and Ice Data Center (NSIDC) at the University of Colorado.

Sea ice in the Arctic goes through a regular yearly cycle of growing and melting. While it doesn’t raise sea level, says Meier, it does have an effect on the climate systems through how much energy gets absorbed from the sun.

Since the Arctic sea ice observational record began in 1979,  the trend of ice melt went from slow and steady to more significant as time went on.

Over the last 10 years, according to Meier, this trend quickly began to escalate, with record-breaking years of sea ice melt along the way. The significant drop in the amount of Arctic sea ice, says Meier, “is a kind of an exclamation point on the long term trend.”

Scattered ice floes are seen from the bridge of the USCGC Healy on August 20, 2012 northwest of Barrow, Alaska. Arctic sea ice fell to its lowest daily extent in the satellite record on Sunday, August 26, 2012. (Photo: U.S. Coast Guard)

Scattered ice floes seen from the bridge of the USCGC Healy on August 20, 2012 northwest of Barrow, Alaska. Arctic sea ice fell to its lowest daily extent in the satellite record on Sunday, August 26, 2012. (Photo: U.S. Coast Guard)

NSIDC officials say the previous record low, set back in 2007, happened because of a near-perfect summer weather for melting ice.

“The Arctic used to be dominated by multiyear ice, or ice that stayed around for several years,” Meier said. “Now it’s becoming more of a seasonal ice cover and large areas are now prone to melting out in summer.”

Because of this, he said, what’s occurring now is an overall thinning of the multiyear ice cover, as well as a decrease in the seasonal ice cover.

That thinning continues throughout the entire year because the ice in the wintertime is also thinner than it used to be, reflecting what Meier calls “another big change in the Arctic sea ice system.”

Meier worries about changes to the Arctic, and consequently Earth’s weather systems, should this trend of escalated sea ice melt continue.

The sea ice is very reflective, it’s white and reflects most of the sun’s energy, says Meier. Because there is continuous daylight during the Arctic summer, most of that solar energy is reflected back into space; it doesn’t warm things and helps keep the Arctic cool. Meier calls this process not only the Arctic’s “air conditioner,” but also the entire Earth’s “air conditioner” as well.

“As we lose that sea ice in the summertime,” says Meier, “it gets replaced by the ocean which is very dark relative to the sunlight. It absorbs most of that energy, reflects very little of it, and that energy then heats up the ocean, which heats up the atmosphere and makes the entire Arctic warmer than it normally would be without sea ice.”

Animals which have long resided in the Arctic, such as the polar bear, could be in danger if the current trend of Arctic sea ice melt continues (Photo: Yukon White Light on Flickr/Creative Commons)

This causes greater warming, taking what has been the globe’s air conditioner and kind of “draining out the coolant,” says Meier.  As a result, the ability and efficiency of that process to help cool the Earth is reduced as more and more sea ice is lost in the summertime.

There has been a sort of climate balance on Earth between cold in the polar areas and warmth in the equatorial regions. The contrast between the polar cold and the equatorial warmth, according to Meier, sets up weather patterns like the jet-stream, ocean currents, storm tracks and where, when and how much it rains.

Changes in either climate system  throw off this balance and disrupt weather patterns. There’s not enough data right now to say for sure what the exact impacts these weather changes will bring, but Meier  suspects areas that are dependent on predictable weather patterns – such as agriculture and other things needed to help sustain life on Earth – may be affected.  It’s possible, he says, that droughts may become harsher or that more flooding will occur.

Accelerated melting could also impact animals,  such as polar bears, who make their homes on the Arctic ice. Meier says some of these polar animals will find new habitats to live in, but others will be forced to either adapt to the changing climate conditions or face extinction.

Walt Meier joins us this weekend on the radio edition of Science World.  Check out the right column for scheduled air-times or listen now to the interview below.

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Rick Pantaleo
Rick Pantaleo maintains the Science World blog and writes stories for VOA’s web and radio on a variety of science, technology and health topics. He also occasionally appears on various VOA programs to talk about the latest scientific news. Rick joined VOA in 1992 after a 20 year career in commercial broadcasting.

17 responses to “Arctic Sea Ice Melts More Each Year”

  1. Alexandra says:

    wow!! I am doing a project on this for school!! Current events, and a huge poster board!! Thank you mrs. miller!!

  2. […] change, but is also a massive contributor to it. In perhaps an overly simplistic nutshell, …Arctic Sea Ice Melts More Each YearVoice of America (blog)Arctic ice melt 'like adding 20 years of CO2 emissions'BBC […]

  3. […] Peter Wadhams has told BBC Newsnight. White ice reflects more sunlight than open water, …Arctic Sea Ice Melts More Each YearVoice of America (blog)UK ice boffin: 'Arctic melt equivalent to 20 years of CO 2 […]

  4. Data Don says:

    t just occurred to me that the earth, in order to exist for 4.5 billion years, must has great survival instincts. Also I have been observing the sun current and lit’s long term activity. Currently the sun has had the lowest activity in hundreds of years. Particularly, it is similar to the maunder era when we had a very cold phase and severe freezing.

    With these thought in mind, I began to wonder if the earth is preparing itself for the cold era. What I mean is this….If the ice cover reflects the sun, it would be an advantage for the earth to reflect the sun back to space. I understand that is the current fear. Conversely, the oceans, without the ice cover, will absorb the suns rays and how the heat that it absorbs. Now if the earth and mother nature, God or whatever, knows that a cold phrase is upcoming, wouldn’t it be an advantage to have the oceans to have the ability to store as much heat as possible.

    Maybe we are looking at this all wrong. After all, humans are, by nature, fearful of change and we usually apply whatever knowledge or fearful thoughts we have. I think that this could be a instinct that we are endowed with so that we protect ourselves but , as we all know, sometimes it doesn’t always work to our advantage.

    As the current phraseology would put it…..I’m just saying!

    • DSL350 says:

      Data Don–

      An interesting Gaia-related idea. However, the 600,000 years has been one long glacial period punctuated by a few short interglacials. If the Earth is storing up energy to provide balance, why didn’t it happen (or work) the last few times?

      Also, we know what atmospheric CO2 does. We’ve measured the effect directly. The radiative properties of CO2 have been tested for over a century, and non-climate related applications based on our understanding of CO2 have been in use for decades. If the Earth is managing its own temp, then we’re puppets, because our CO2 is definitely part of the equation. Interestingly, several studies have found that glacial inception will not begin with atmospheric CO2 concentration greater than 280ppm (see Tzedakis et al. (2012)). We’re at 395ppm and climbing rapidly. In other words, we may skip the next ice age.

      Finally, advantageous to whom? Does the Earth need life? Does life provide the Earth with anything we would recognize as “good,” and if we are unable to recognize “good” and “bad” from the point of view of the Earth (if such a point of view exists), then there’s no use in wasting thought on it.

  5. Data Don says:

    Sorry, but the cooling that I am talking about is what many presume that is going to happen with the upcoming solar activity, or should I say, inactivity for the next 30 to 50 years. But as far as the past is concerned, I don’t assume to have enough knowledge to know what or why the earth did what it did in the past, but it did survive. Maybe it took billions of years to fine tune itself to support life as we know it now and that is why we are able to survive on earth and now earth has developed methods to, such as the storage of energy to survive cold spells, which just so happens to be in a temperature range that we can also survive. Who knows?

    From what I understand, C02 concentration, some estimate that the human share of atmospheric carbon dioxide is as small as 3 percent. I did read this:

    “According to David J. C. MacKay, professor of natural philosophy in the Department of Physics at the University of Cambridge, the burning of fossil fuels sends seven gigatons (3.27 percent) of carbon dioxide into the atmosphere each year, while the biosphere and oceans account for 440 (55.28 percent) and 330 (41.46 percent) gigatons, respectively.”

    I also read that during our current Phanerozoic era had C02 levels way, way higher than exist now. I read levels as high as 6500ppm. The average was about 2500ppm. So with that in mind the earth has really calmed down and what the hell will our measly 11.85 ppm (3% of 395) contribution going to affect if the earth supports C02 levels of 6500ppm?

    The advantage that I spoke of related to the earth’s advantage to store warmth during a cold period. If storage energy is a part of a cycle of life, I think that it would be an advantage to store energy to survive as the state earth is in now. I mean, isn’t everyone worried about saving the planet? I just put forth the idea that maybe the earth is way ahead of us and we don’t know how to interpret what it is doing.

    I don’t know what the hell you were talking about with your references to earth needing life or the good and bad from earths point of view. Sounds like you are thinking too much or you have some pretty good weed. However, I think you summed it up best when you stated “there’s no use in wasting thought on it!”

  6. Merc says:

    Data Don,

    That 3% figure is per year. The ocean and the trees suck up 2% of that. So that leaves 1% per year extra. But CO2 is a long lived gas. It stays there. So add that 1% to last years 1% and keep adding to way back to when the industrial revolution began in mid 19th century. Pre-Industrial CO2 was less than 300ppm. After about 150 years of adding tiny percentages the amount gradually increases to close to 400ppm

    So man is responsible for 25% of the atmospheric CO2 because

    a) it is a very stable long-lived gas*
    b) we add a little bit every year

    * as opposed to methane which burns up every time lighning strikes, but methane is a much stronger greenhouse gas so its swings and roundabouts.

  7. Data Don says:

    You can’t add percentiles like you do apples. If it is 3% in one year, it remains 3% because the other 97% remains also. The facts remain that we had much higher C02 levels in the past and the earth survived. What counter steps that earth naturally may have taken, if any, to survive, I don’t know. What I put forth is that I think that it is possible that the earth is depleting its ice caps to store heat in our oceans to counter an anticipated upcoming slow period of solar activity that will drop temperatures for the next 30 to 50 years.

  8. Merc says:

    You’re overthinking this. Just think about that 275 ppm before the industrial revolution. We keep adding to that.

    As for those other levels you were talking about, I have also read about levels of 8000 ppm about 500 milions years ago. But that was a different Earth orbiting a different sun. A different sun because it is gradually getting hotter, 500 mya it was only 97% of the radiance it supplies now. A different Earth because continental drift means that the continents were in different positions, I don’t think that Antarctica was even at the South Pole. There were different ocean currents, so forget the Gulf Stream. So CO2 built up to 8000ppm before it balance was achieved with the various long and short carbon cycles. So its very hard to make comparisons.

    • Data Don says:

      Well, again, you are showing that the earth has a way to react and prepares for changes that are brought upon itself. That is exactly what was my original thought….that maybe the depletion of the ice caps are a defensive mechanism between the earth and sun that helps prepare the earth for the next cyclical bout of low activity on the sun. With less ice that reflects heat back into the atmosphere and more water to absorb and store heat energy, would the earth be more prepare for a downturn in temperatures? Wouldn’t it be able to keep a more constant temperature if the sun, in fact, becomes less active? Which, in fact, it already has and we are a step behind the earth in thinking that we are getting warmer without a cause. In this scenario, I am discounting the MMGW as having a MAJOR role in GW. It may have contributed some but, I feel and it a matter of dispute, it is not the driving force. As you probably, or should, know that the sun has experienced one of the most active periods in the past fifty years which could count for most of the rise in temperatures.

      “Just think about that 275 ppm before the industrial revolution. We keep adding to that.”

      Do you think that the earth stopped producing it own C02 once the industrial revolution started?

      As I stated earlier,3.27% of the total C02 in the atmosphere is the current contribution of C02. That leaves 96.73% of natural causes. Of course, we should strive to lower that contribution (that is why I use a manual push mower…funny thing is my kids won’t use it but they believe in MMGW more than I do). However, we shouldn’t scare people into thinking that the sky is falling if nature is largely at work and there is nothing that we can do about that. And, as I am trying to put forth, just maybe we are seeing earth preparing for a coming cold spell and, again, are crying about something that we are not truly understanding….that is mother nature at work.

  9. praful says:

    researchers r predicting ice free summer, but we r predicting ICE AGE in the nearby years….think…

  10. Jnan Bora says:

    The Arctic ice is melting more every year. So,the Antarctic ice also is gonna follow the suit pretty soon. Likewise. The ocean level is rising more every year. What does it mean ? How will it be like when the Arctic moves to the Middle East and the Antarctic goes to the Middle West ? And vice verce . Will it be not possible ? The Holy Scripture says that everything is possible. But not to man , only God . It says that when God speaks, things happen and events take place in the universe. Well, who is God ? Absolute One . True One. Many people introduce the Devil as god to one another either knowingly or unknowingly.How can one know God ? Everybody knows some sort of god. Even an atheist worships some kind of god unknowingly or unconciousely or indirectly . Now there are so many signs that denote the possible creation of the New Heaven and the New Earth . Will the prophecies of Isaiah and Revelation come true indeed ? Who is going to take the people of this earth to the New Earth for safety ? Oh , someone says God will take His followers to the new earth . But the problem is how one can know God in spirit and truth. Maybe, the wealthiest of the world are planning their escapes to other planets and their moons by space vehicles. Is there any possibility to create environment for sustenance of life there?