Visualizing The Missing Ice

The map below shows the difference between National Ice Center ice (yellow) and NSIDC ice (red.)

NSIDC uses microwave emissions to spot ice, and they are missing lots of ice which is seen in visible light.

//ARCTIC.IO/OBSERVATIONS/8/2012-08-18/8-N76.083133-W160.925244

National Ice Center August 18 2012 vs August 18 2007.

About Tony Heller

Just having fun
This entry was posted in Uncategorized. Bookmark the permalink.

37 Responses to Visualizing The Missing Ice

  1. Andy DC says:

    It seems that measuring ice extent is highly subjective, thus prone to deliberate misrepresentation on the part of alarmist propagandists. According to them, if ice is broken up by a storm (or icebreakers for that matter), it no longer exists.

  2. Peter Ellis says:

    Almost right – NSIDC use microwave emissions, not reflections. There are satellites that use microwave reflection (or rather, scattering), e.g. QuickScat, but that’s not the ones used by NSIDC/IJIS/Bremen.

    Tell me, that ice you zoom in on in the top picture: does it look like a large volume to you? Concentration is certainly very low – near the borderline to count in extent, or perhaps even below. Healy’s webcam shows it to be very thin and sparse.

    http://icefloe.net/Aloftcon_Photos/index.php?album=2012

    The fact remains that when you compare like-for-like (i.e. compare NSIDC to NSIDC, Bremen to Bremen, IJIS to IJIS, National Ice Center to National Ice Center), this year is either a little below or a little above the corresponding date in August 2007.

  3. Travis says:

    NIC includes ice of all concentrations (including 0-15%) in their ice edge calculations. NSIDC follows a more common convention of using only 15% concentration ice and higher in their calculations, which is why NIC’s numbers are so much higher than other groups’ analyses. Most organizations use >15% because including ice of less than 15% concentration tends to end up including a fair amount of random “noise” where there clearly isn’t ice. That is why NIC uses a 3-day average in their analysis rather than doing a daily ice plot like most other organizations. DMI uses 30% as their minimum, which is why they show ice extent at a record minimum already with a few weeks to go yet in the traditional melt season.

    • NIC shows a lot more ice than they did in 2007.

    • Travis says:

      Steven,

      By all accounts, those winds from the recent storm served to spread out the ice pack rather than condense it. You know better than that. Think about it from your own words: if it the storm “broke up the ice” as you say, is the ice getting more condensed or more spread out? That’s a no-brainer.

      • I’m really tired of stupid straw man arguments.

      • Travis says:

        Then stop making them.

      • Travis says:

        Last point from Julienne Stroeve’s analysis that you so kindly linked to:

        “Storm rotation (counterclockwise) spread out ice over larger area”

        Thank you for providing even more evidence for my assertion.

      • Travis says:

        If it had all melted, we wouldn’t be having this lovely conversation. It was multi-year ice that the storm separated from the main ice pack, and as you have pointed out, it takes a while for multi-year ice to melt. As a result, we have large swaths of ocean that have very low concentrations of sea ice in them (less than 15%) that are slowly melting but are still significant enough to show up on visible-wavelength satellite images.

        As I pointed out, that was not the effect of the winds in 2007; the 2007 winds served to compact the ice pack, which meant there were few areas of low concentration sea ice (unlike the rather large area this year). That is why organizations that track sea ice area (rather than extent) like Cryosphere Today and DMI show the current sea ice area for 2012 to be very close to the minimum area for 2007, whereas most organizations that show only ice extent indicate there’s still a ways to go until we hit the 2007 minimum for extent.

        Given the situation, any organization (like NIC or the Canadians) that include ice of less than 15% concentration are going to show a much higher extent than those that don’t. I don’t see why this is so difficult for you to understand. I suspect it actually isn’t. Like your profile on this site says: you’re “Just having fun.”

      • Travis says:

        “The NIC graph shows a lot of ice covered water which the NSIDC map doesn’t.”

        Yes. Yes, it does. Apparently you don’t care why. And now we’ve come full circle. Good evening to you, Mr. Goddard.

  4. ntesdorf says:

    From the look of those ice extent maps, someone is lying to us. Could it possibly be NSIDC

Leave a Reply

Your email address will not be published. Required fields are marked *