Climate Change & Global Warming

[jz]

 

 

Death spiral? I don't think so.

 

 

Could you please give the source of your graph? Otherwise it is difficult for others to check the validity of your claim. Also I'm a bit concerned about the label of your y-axis, area in pixels? The Arctic ice really has shrunk

[crofter]

 

Could you please give the source of your graph?

 

http://www7320.nrlssc.navy.mil/pips2/archive/pips2_thick/

[jz]

^^

Thanks for that, your link actually points to a directory list, but if you go to

http://www7320.nrlssc.navy.mil/pips2/ this gives, I presume, the website you are referring to .

 

Now perhaps I'm being snobbish but tacky javascript snowfall, and a site which states "Note: This website best viewed with Internet Explorer 4.0 or better and screen size of 800 x 600 or better." does not inspire confidence.

 

Even if it is "an Official U.S. Navy Web Site".

 

Also your graph is only for the last 3 years; the data would be more robust if looked at over a longer time scale. The Met Office site would be a better, more scientifically worthwhile, source for climate change discussion.

[ArabiaTerra]

jz, this is the place I go to to get the latest on the Arctic ice situation:

 

http://nsidc.org/arcticseaicenews/index.html

 

The ice extent graph is updated daily.

 

As can be seen, the ice extent is currently below the record set in 2007 despite a late recovery due to a colder than average March.

 

This graph shows the ice volume situation which gives a truer representation of the situation compared to the ice extent data:

 

http://psc.apl.washington.edu/ArcticSeaiceVolume/images/SPIOMASIceVolumeAnomalyCurrent.png

 

from here

[ArabiaTerra]

This is an excellent laymans explanation of Ocean Acidification:

 

http://profmandia.wordpress.com/2010/06/06/the-800-lb-gorilla-in-the-ocean/

 

From one of the comments:

 

Anyone who saw the effects of acid rain knows what acid does to lime buildings/statues; the same will happen to calcium carbonate shells. Sure, carbonic acid is only weak, however unlike the rain, they’re bathing in it all the time. It will reduce the fitness of any shelled oceanic life form.

[crofter]

 

Also your graph is only for the last 3 years; the data would be more robust if looked at over a longer time scale.

 

Yes, I agree.

 

The Met Office site would be a better, more scientifically worthwhile, source for climate change discussion.

 

Had a look at that site but to my luddite eyes it is a bit modern and cluttered. If you could post the link to the met office directories of arctic ice extent/thickness/volume that would be appreciated.

[jz]

... If you could post the link to the met office directories of arctic ice extent/thickness/volume that would be appreciated.

Crofter, this is the nearest to your request http://hadobs.metoffice.com/hadisst/

[crofter]

Crofter, this is the nearest to your request http://hadobs.metoffice.com/hadisst/

 

Thanks for that. However:

 

The SSM/I satellite that is used to provide the data for the sea ice analysis in HadISST suffered a significant degradation in performance through January and February 2009. The problem affects HadISST fields from January 2009 and probably causes an underestimate of ice extent and concentration. It will also affect sea surface temperature in sea ice areas because the SSTs are estimated from the sea ice concentration (see Rayner et al. 2003). For the time being we will continue to process the data in the usual manner, but users should realise that the fields should be treated with caution.

 

Maybe the US Navy real actual measurements of arctic sst are more reliable.

[Carlos]

From my reading the US Navy site is using computer modelling?

As of July 1996, a coupled ice-ocean model, the Polar Ice Prediction System (PIPS 2.0), was implemented operationally by FNMOC

 

That might well be guided by real measurements, but I've not seen information on how/when/where.

Now the modelling might be good, and you'd hope it was, but there has been some suspicion of computer modelling of weather/climate effects voiced here before....

[Ghostrider]

(In fact, a credible source for all of the figures they quote would be good).

 

This is rather the crux of the whole debate though, is it not? Just how credible is credible, regardless what stance is taken on the subject?

 

Climate science is a relatively young science, and its an imprecise science as it contains too many variables, interactions and chain reactions to be anything else. Arguably the only credible figures are those for what has already occured, and even they're dubious as they're neither comprehensive or accurate enough, or cover a period long enough to give the full picture.

[ArabiaTerra]

This is rather the crux of the whole debate though, is it not? Just how credible is credible, regardless what stance is taken on the subject?

 

Climate science is a relatively young science, and its an imprecise science as it contains too many variables, interactions and chain reactions to be anything else. Arguably the only credible figures are those for what has already occured, and even they're dubious as they're neither comprehensive or accurate enough, or cover a period long enough to give the full picture.

 

By credible source, I mean from the scientists, not from some political organisation financed by the fossil fuel industry and which has a vested interest in denying reality. And I'm not sure what you mean by not covering a long enough period. Is 800,000 years not long enough for you? That's how far back the ice core data goes, and this data shows that today's CO2 levels are unprecedented.

 

In fact, we have climate data going back 542,000,000 years. Is that long enough for you?

 

http://upload.wikimedia.org/wikipedia/commons/thumb/f/f5/All_palaeotemps.png/800px-All_palaeotemps.png

 

Maybe the US Navy real actual measurements of arctic sst are more reliable.

Crofter, why don't you go to the NSDIC for your data? You've been quite happy to trust them in the past. Or are they now unreliable because what they're saying doesn't agree with how you would like things to be?

 

In May, Arctic air temperatures remained above average, and sea ice extent declined at a rapid pace. At the end of the month, extent fell near the level recorded in 2006, the lowest in the satellite record for the end of May. Analysis from scientists at the University of Washington suggests that ice volume has continued to decline compared to recent years.

 

http://nsidc.org/images/arcticseaicenews/20100608_Figure2_thumb.png

 

from here.

[paulb]

AT that chart is showing a higher level than 2006/7 and a near normal level for most of the winter. as this is ment to be an el nino sorry about the spelling. it would be valid to examine like for like years. looking at your larger graph its clear that the temp is just recovering from a cold period.

[crofter]

From my reading the US Navy site is using computer modelling?

As of July 1996, a coupled ice-ocean model, the Polar Ice Prediction System (PIPS 2.0), was implemented operationally by FNMOC

 

That might well be guided by real measurements, but I've not seen information on how/when/where.

Now the modelling might be good, and you'd hope it was, but there has been some suspicion of computer modelling of weather/climate effects voiced here before....

 

Yes, it's a model - although they do real measurements too. My point was that an organisation which needs to safely navigate nuclear submarines up there probably has better ice data than a bunch of boffins in Hadley with a broken satellite.

[crofter]

 

Crofter, why don't you go to the NSDIC for your data? You've been quite happy to trust them in the past. Or are they now unreliable because what they're saying doesn't agree with how you would like things to be?

 

 

I don't have a problem with that graph. As paulb says, it goes down and up. How did you get it shrunk so small?

[skaterboy]

What that shows AT is that temps are lower now than they have been for the majority of human existence.

Also if you keep the time to the same scale for the whole of the period temperatures now are doing pretty much the same as they have been doing for the last half billion years, changing erratically.

Thanks for that AT you have just proved without any shadow of a doubt that you and the rest of the climate change doom sayers are full of poop.