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Post by steve on Aug 25, 2009 9:50:57 GMT
I extent dropping. Less than 5.5 looking increasingly likely Yes, but I don't know who to trust anymore. Cryosphere is showing that ice isn't melting at all. Presumably they all use different ways of analysing the data. As long as each site remains consistent then the comparison may remain valid. Currently they're all showing roughly 1 million sq kilometres higher than the 2008 minimum. The original post linked to the JAXA data, so I assume most people's answers were based on that baseline. www.ijis.iarc.uaf.edu/en/home/seaice_extent.htm
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Post by robertski on Aug 25, 2009 10:12:54 GMT
Yes, but I don't know who to trust anymore. Cryosphere is showing that ice isn't melting at all. Presumably they all use different ways of analysing the data. As long as each site remains consistent then the comparison may remain valid. Currently they're all showing roughly 1 million sq kilometres higher than the 2008 minimum. The original post linked to the JAXA data, so I assume most people's answers were based on that baseline. www.ijis.iarc.uaf.edu/en/home/seaice_extent.htmMy understanding, although i cannot confirm, is that the Jaxa data is faulty due to i believe a technical issue. I am not sure of this however, but it may be worth investigating. Here is the article i am refering to... icecap.us/index.php/go/political-climate/nsidc_pulls_the_plug_on_arctic_sea_ice_graphs/Not sure if it is still relevent but i am hearing that people are discounting Jaxa at the moment.
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Post by woodstove on Aug 25, 2009 12:38:53 GMT
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Post by hunter on Aug 25, 2009 12:54:34 GMT
As predicted by many not infected with the AGW meme.
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Post by kiwistonewall on Aug 26, 2009 8:05:54 GMT
Jaxa (AMSR-E) isn't faulty, just (the algorithms are) badly calibrated, and skips all ice extent less than about 80-90% as I've shown many times. In fact, it appears to need Multiyear ice. This is well understood, as the older ice is denser, and has a different radar reflection than new ice. The huge area shown as ice north of Alaska ( pafc.arh.noaa.gov/data/ice/ice.png), but missing from AMSR_E is mainly new ice. The Alaskan data is accurate, the AMSR-E is just way out. Overlays to compare: i410.photobucket.com/albums/pp183/kiwistonewall/layer.gif
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Post by robertski on Aug 26, 2009 8:12:03 GMT
Jaxa (AMSR-E) isn't faulty, just (the algorithms are) badly calibrated, and skips all ice extent less than about 80-90% as I've shown many times. In fact, it appears to need Multiyear ice. This is well understood, as the older ice is denser, and has a different radar reflection than new ice. The huge area shown as ice north of Alaska ( pafc.arh.noaa.gov/data/ice/ice.png), but missing from AMSR_E is mainly new ice. The Alaskan data is accurate, the AMSR-E is just way out. Overlays to compare: i410.photobucket.com/albums/pp183/kiwistonewall/layer.gifThanks for that, explains it nicely. Either way, it needs to be disregarded as it is wrong for whatever reason.
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Post by poitsplace on Aug 26, 2009 8:41:28 GMT
Thanks for that, explains it nicely. Either way, it needs to be disregarded as it is wrong for whatever reason. Nobody's going to own up to the error for a while. They're treating the missing ice (most of which is actually there right now) as a sort of "smoking gun" for climate change.
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Post by glc on Aug 26, 2009 12:19:41 GMT
Posted by woodstove on Yesterday at 7:38am Whichever service's number is used, Arctic ROOS continues to have its own take on the current trend (albeit one day less recent than IARC-JAXA).Ok - so JAXA's no longer flavour of the month. However the relative decline (if not absolute numbers) are similar to Artic-ROOS. This link shows Artic ROOS long term observations. arctic-roos.org/observations/satellite-data/sea-ice/total-icearea-from-1978-2007See plots 2, 3 ...... .....also Plots 4 and 5. Sea Ice Extent Minimum down 7.467% per decade Sea Ice Area Minimum down 8.896% per decade Still looks like a recovery to me. It doesn't look like one to me.
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Post by poitsplace on Aug 26, 2009 13:54:05 GMT
Posted by woodstove on Yesterday at 7:38am Whichever service's number is used, Arctic ROOS continues to have its own take on the current trend (albeit one day less recent than IARC-JAXA).Ok - so JAXA's no longer flavour of the month. However the relative decline (if not absolute numbers) are similar to Artic-ROOS. This link shows Artic ROOS long term observations. arctic-roos.org/observations/satellite-data/sea-ice/total-icearea-from-1978-2007See plots 2, 3 ...... .....also Plots 4 and 5. Sea Ice Extent Minimum down 7.467% per decade Sea Ice Area Minimum down 8.896% per decade Still looks like a recovery to me. It doesn't look like one to me. The real problem here is we're not entirely sure how much warming was natural and how much (if any) was CO2. We're not sure how much ice melt was the natural cycle and how much is from the warming. Does it do this every time the ocean currents switch? Will it now be GAINING 8% per decade? We have very little information on the natural progression of the warming/cooling cycles.
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Post by woodstove on Aug 26, 2009 14:44:52 GMT
Posted by woodstove on Yesterday at 7:38am Whichever service's number is used, Arctic ROOS continues to have its own take on the current trend (albeit one day less recent than IARC-JAXA).Ok - so JAXA's no longer flavour of the month. However the relative decline (if not absolute numbers) are similar to Artic-ROOS. This link shows Artic ROOS long term observations. arctic-roos.org/observations/satellite-data/sea-ice/total-icearea-from-1978-2007See plots 2, 3 ...... .....also Plots 4 and 5. Sea Ice Extent Minimum down 7.467% per decade Sea Ice Area Minimum down 8.896% per decade Still looks like a recovery to me. It doesn't look like one to me. As others have asked, do you require the ice to rebound in a single year in order to see a recovery? Do you, by the way, reject NOAA's ice map (provided above by Kiwi) showing far more widespread ice in the Chukchi Sea and Beaufort Sea than JAXA, Arctic ROOS, and NSIDC? We're still waiting, with bellies ready to laugh, for your explanation regarding the 2007 yin-yang of sea ice in the two hemispheres, i.e. all-time record in the Antarctic (which has shown a slow, relatively steady increase of area during the satellite era). Please explain how the increase in Antarctic sea ice is in keeping with theories regarding co2-related global warming.
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Post by steve on Aug 26, 2009 15:59:35 GMT
If Roos is flavour of the month, then my wild guess - of a reversion to trend - can still be tested. Well, it looks like it will be below the 30-year trend line, so I'll likely be off with my guess.
My next year's prediction is that Roos will be out of favour for showing too little ice.
On that note, I'm going to take Woodstove's advice from another thread, and get away from my computer screen and see some nature for a bit. Anyone living in Colorado fancy a beer?
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Post by sigurdur on Aug 26, 2009 16:22:18 GMT
If Roos is flavour of the month, then my wild guess - of a reversion to trend - can still be tested. Well, it looks like it will be below the 30-year trend line, so I'll likely be off with my guess. My next year's prediction is that Roos will be out of favour for showing too little ice. On that note, I'm going to take Woodstove's advice from another thread, and get away from my computer screen and see some nature for a bit. Anyone living in Colorado fancy a beer? Steve, Take a drive to ND and enjoy nature. I think they still have beer up here, if not that, then I will feed ya some new spuds.
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Post by magellan on Aug 26, 2009 16:27:00 GMT
If Roos is flavour of the month, then my wild guess - of a reversion to trend - can still be tested. Well, it looks like it will be below the 30-year trend line, so I'll likely be off with my guess. My next year's prediction is that Roos will be out of favour for showing too little ice. On that note, I'm going to take Woodstove's advice from another thread, and get away from my computer screen and see some nature for a bit. Anyone living in Colorado fancy a beer? I have no flavor of the month and don't know enough about the methods and procedures to form an opinion, so say let them all hash it out and may the best product prevail. I don't drink, but you're welcome in Michigan for a visit. We have horses, ATV's and room to ride them. I gave up the city life 30 years ago; never looked back.
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Post by glc on Aug 26, 2009 16:36:54 GMT
As others have asked, do you require the ice to rebound in a single year in order to see a recovery? No I don't - but I do require more evidence than the fact there is more ice now than during the massive loss in 2007. Do you, by the way, reject NOAA's ice map (provided above by Kiwi) showing far more widespread ice in the Chukchi Sea and Beaufort Sea than JAXA, Arctic ROOS, and NSIDC?Dunno - I haven't looked. You seem happy to flit from source to source depending on which gives the preferred result. Both Arctic Roos and Jaxa have been fairly consisent over the last few years but because Arctic Roos tends to report more ice than Jaxa, I can see it's attraction. Now you bring another source which supposedly shows more ice than the rest. But what was it showing last year or 10 years ago -what is it showing in other regions. This is exactly the sort of thing Michael Mann did with the H-S. He used different data sources to show that 20th century warming was unprecedented. We're still waiting, with bellies ready to laugh, for your explanation regarding the 2007 yin-yang of sea ice in the two hemispheres, i.e. all-time record in the Antarctic (which has shown a slow, relatively steady increase of area during the satellite era). Please explain how the increase in Antarctic sea ice is in keeping with theories regarding co2-related global warming.Now I'm not a great fan of climate models but to give them their due the predictions for the key climate indicators do tend to be in the right direction, e.g. temperatures and arctic ice to name two. There is also this from the IPCC TAR (2001). For the change in annual mean surface air temperature in the various cases, the model experiments show the familiar pattern documented in the SAR with a maximum warming in the high latitudes of the Northern Hemisphere and a minimum in the Southern Ocean (due to ocean heat uptake) evident in the zonal mean for the CMIP2 models (Figure 9.8) and the geographical patterns for all categories of models (Figure 9.10).See www.grida.no/publications/other/ipcc%5Ftar/?src=/climate/ipcc_tar/wg1/351.htm
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Post by woodstove on Aug 26, 2009 16:38:23 GMT
If Roos is flavour of the month, then my wild guess - of a reversion to trend - can still be tested. Well, it looks like it will be below the 30-year trend line, so I'll likely be off with my guess. My next year's prediction is that Roos will be out of favour for showing too little ice. On that note, I'm going to take Woodstove's advice from another thread, and get away from my computer screen and see some nature for a bit. Anyone living in Colorado fancy a beer? Have fun, Steve. Sleep overnight in the back country, if you can, or the closest thing to it that you can get.
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