Moderated Global Warming Discussion

[Trakar]

This link of satellite evidence - specifically, Jason-1, Jason-2, Envisat, ERS2 - shows that sea levels have been declined from their peaks in 2009-2010. Envisat shows lower levels than the peak value in 2002.


Also, the web page claims that the Envisat is the "most sophisticated" sea level satellite.

I don't know why the other satellite data sets are not graphed past 2003-2006.

So we're back to international government conspiracies again?

 

[Reality Check]

This link of satellite evidence - specifically, Jason-1, Jason-2, Envisat, ERS2 - shows that sea levels have been declined from their peaks in 2009-2010. Envisat shows lower levels than the peak value in 2002.

You are right that link shows that sea levels have been declined from their peaks in 2009-2010.
What this web page neglects to tell its readers is that this is expected!
What this web page neglects to tell its readers is that this is still a trend of ~3mm/yr increase in sea level over climate appropriate time scales (multiple decades).

There was a change from El Nino to La Nina in 2010. La Nina causes more rainfall and snowfall on land and thus a drop in global sea levels.

See Why did sea level fall in 2010?

 

[metamars]

This link of satellite evidence - specifically, Jason-1, Jason-2, Envisat, ERS2 - shows that sea levels have been declined from their peaks in 2009-2010. Envisat shows lower levels than the peak value in 2002.

Sorry, Envisat shows lower levels than the peak value in 2005, not 2002. It starts in 2004.

 

[Pixel42]

What this web page neglects to tell its readers is that this is expected!
What this web page neglects to tell its readers is that this is still a trend of ~3mm/yr increase in sea level over climate appropriate time scales (multiple decades).

Why do some people find it so hard to grasp that there's a minimum amount of time for which you need to observe to detect any underlying trend, and that that minimum period depends on the size of the trend and the level of random noise?

If Nigel Lawson pointed out on April 11th that although there was a warming trend in the first quarter of the year there had been no further warming since April 1st, heavily implying that that meant that the warming had stopped and the basic physics which tells us that the Northern Hemisphere will warm for the first half of year was wrong, people would think he was a blithering idiot. Yet he can observe in his Radio Times article that although there was a warming trend in the last quarter of the 20th century there's been no further warming this century, and people will fall for the false implication in their droves.

Anybody who tries to attach significance to changes in global temperatures, sea levels, Artic sea ice extent or anything else connected with the climate over any period less than that for which any trend would be statistically significant (usually at least 15-20 years) can be instantly dismissed as either wilfully ignorant or deliberately misrepresenting the data.

 

[Trakar]

You are right that link shows that sea levels have been declined from their peaks in 2009-2010.
What this web page neglects to tell its readers is that this is expected!
What this web page neglects to tell its readers is that this is still a trend of ~3mm/yr increase in sea level over climate appropriate time scales (multiple decades).

There was a change from El Nino to La Nina in 2010. La Nina causes more rainfall and snowfall on land and thus a drop in global sea levels.

See Why did sea level fall in 2010?

or, if you prefer:

http://www.jpl.nasa.gov/news/news.cfm?release=2011-262

 

[lomiller]

This link of satellite evidence - specifically, Jason-1, Jason-2, Envisat, ERS2 - shows that sea levels have been declined from their peaks in 2009-2010. Envisat shows lower levels than the peak value in 2002.


Also, the web page claims that the Envisat is the "most sophisticated" sea level satellite.

I don't know why the other satellite data sets are not graphed past 2003-2006.

As already discussed, this is well within the normal range of water being exchanged between sea and land.

You need to treat any claims regarding trends that are based on very limited time periods with great scepticism. If someone is saying a trend has changed, you need to make sure they have done the math to find out if they have enough data to make statistically significant claims.

 

[Piggy]

So what's up with these stories going around in UK about the Russians finding hundreds of arctic methane vents up to 1000 meters across?

If we're looking at a large-scale methane dump, that's not a good thing.

But I'm only encountering this story in outlets I'm unfamiliar with or in places like the Daily Mail, so what's up here?

Shock as retreat of Arctic sea ice releases deadly greenhouse gas: Russian research team astonished after finding 'fountains' of methane bubbling to surface

Scientists worry about giant plumes of methane in Arctic Ocean

 

[AlBell]

Apparently they didn't light a match yet.

That would be a spectacular albeit frightening sight.

 

[mike3]

The CRU doesn’t produce source data; rather it receives it from a variety of national weather services. The idea that they somehow broke into countries weather services and destroyed their data is a laughable conspiracy theory. If the person you are discussing this with is willing to believe that then no amount of fact or science will change their mind unfortunately.

It seems like there's a pattern here: warming advocates can point to impressive scientific arguments, while deniers point to conspiracy theories. Hmm.

 

[Trakar]

So what's up with these stories going around in UK about the Russians finding hundreds of arctic methane vents up to 1000 meters across?

If we're looking at a large-scale methane dump, that's not a good thing.

But I'm only encountering this story in outlets I'm unfamiliar with or in places like the Daily Mail, so what's up here?

Shock as retreat of Arctic sea ice releases deadly greenhouse gas: Russian research team astonished after finding 'fountains' of methane bubbling to surface

Scientists worry about giant plumes of methane in Arctic Ocean

This is one of the "tipping point" feedbacks that aren't included in existent IPPC projections.

 

[BenBurch]

Well, Piggy, if that is happening there will be amazingly rapid changes.

 

[Trakar]

"Strong atmospheric chemistry feedback to climate warming from Arctic methane emissions"
http://www.agu.org/pubs/crossref/2011/2010GB003845.shtml

"Quantification of seep-related methane gas emissions
at Tommeliten, North Sea"
http://users.ugent.be/~jgreiner/papers/Schneider_etal_2011_CSR.pdf

Commentary:
"Glacial demise and methane’s rise"
http://www.pnas.org/content/108/15/5925.full.pdf+html

"Large methane releases lead to strong aerosol forcing and reduced cloudiness"
http://www.atmos-chem-phys-discuss.net/11/9057/2011/acpd-11-9057-2011.pdf

"Permafrost carbon-climate feedbacks accelerate global warming"
http://www.acclimate-oi.net/sites/default/files/articlesdoc/étude permafrost CC_07.09.2011.pdf

"Estimating the permafrost-carbon feedback on global warming"
http://www.biology.ufl.edu/ecosystemdynamics/Reprints Final All/Schneider_2011.pdf

Just a handful of the many perspectives and considerations regarding methane emissions, released over the last year, all paint a serious and concerning backdrop to what is occurring in the current planetary climate change.

 

[bit_pattern]

So what's up with these stories going around in UK about the Russians finding hundreds of arctic methane vents up to 1000 meters across?

If we're looking at a large-scale methane dump, that's not a good thing.

But I'm only encountering this story in outlets I'm unfamiliar with or in places like the Daily Mail, so what's up here?

Shock as retreat of Arctic sea ice releases deadly greenhouse gas: Russian research team astonished after finding 'fountains' of methane bubbling to surface

Scientists worry about giant plumes of methane in Arctic Ocean

Andy Revkin has an interesting piece on this story, the researchers he spoke to say it's likely that we are just discovering more of these vents rather than that there are more appearing. Over the last decade methane level levelled off and have been dropping somewhat mysteriously, some researchers believe it's to do with changes in rice farming practices in Asia.

http://dotearth.blogs.nytimes.com/2011/12/14/methane-time-bomb-in-arctic-seas-apocalypse-not/

 

[aleCcowaN]

Shock as retreat of Arctic sea ice releases deadly greenhouse gas: Russian research team astonished after finding 'fountains' of methane bubbling to surface

They say that in an area of less than 10,000 square miles (not kilometres) they found more than 100 plumes some of them 1,000 metres wide or more, with concentrations more than 100 times above normal. [They didn't say they were 10 scientists with 100 assistants who took 10 weeks to find out]

They won't tell that in this business -within a time scale of a few generations- CO₂ is sort of a "stock variable" (for the sake of those who say "forget you" to the real-no-nominal knowledge of concepts like integral and derivative, and all one must know before starting to cast the shyest opinion about this whole subject) while methane is more of a "flux variable" (yuck!). Reason? Methane is degraded to CO₂ and water by natural means as it "decays", having an average life of 12 years.

This doesn't mean that methane is harmless, but we have to face the sustained release of many hundreds of millions of tons a year above "normal" levels or a confirmed pseudo-exponential trend during a long period before shouting "pack of wolfs".

Articles that start "As I was going to St Ives I met a problem with seven causes. Every cause had seven scientists researching them. Every scientist had seven papers published ...." are only good to inspire Hollywood script writers and not to enlighten the public.

They are almost as bad as those saying nobody is going to St Ives and having their own Hollywood scripts.

 

[Gwynpaine]

Metamars says in item 4060 above:

Originally Posted by Gwynpaine View Post

T

he evidence from -satellites and tide gauges shows that mean ¬global sea levels are now rising by 3mm a year.

This link of satellite evidence - specifically, Jason-1, Jason-2, Envisat, ERS2 - shows that sea levels have been declined from their peaks in 2009-2010. Envisat shows lower levels than the peak value in 2002.


Also, the web page claims that the Envisat is the "most sophisticated" sea level satellite.

I don't know why the other satellite data sets are not graphed past 2003-2006.

The Gwynpaine referred to cannot have been me. I dont know anything about it. It would be interesting to know in what sense the Envisat data of metamars link is more "sophisticated" than the others. It shows a gentler slope of growth over the short data period between 2004 and 2010 than the longrun gradient established by tho other sources. But it still looks too steep for comfort. It seems that the post-2110 data can be explained as outliers.

 

[aleCcowaN]

It seems like there's a pattern here: warming advocates can point to impressive scientific arguments, while deniers point to conspiracy theories. Hmm.

What begs the questions of why there is some sort of a "debate" in this thread and why somebody is saying "sea level dropped lately" and other is pointing to the right reasons for it in a context of global warming.

The right reply for "sea level dropped lately" is "yes, we are currently in a period of global warming" and/or "how do you believe such a fact relates to a no-warming long-term trend", and let them hang themselves from their own tongue.

It's as simple as caring and educated people who find a flaw in a theory do pounce repeatedly on the same point by means of a strong and consistent argumentation until the theory falls instead of throwing everything they find to the wall in the hope that something will stick. Who said "the seal level dropped lately" had half his/her job done just by getting a reply as if that fact challenges a global warming trend.

Everybody should stop providing free completion for what are just half-baked layman-like short remarks, because who answer such questions are the ones who are providing the challenging part for free.

 

[CapelDodger]

The Gwynpaine referred to cannot have been me. I dont know anything about it.

It's a quoting mess-up. The first part is a quote from the Monbiot extract you posted, of course, the rest is from something else entirely. I do think people should take a little more care with such things, if only so that we know where to lay the blame .

 

[Trakar]

Andy Revkin has an interesting piece on this story, the researchers he spoke to say it's likely that we are just discovering more of these vents rather than that there are more appearing. Over the last decade methane level levelled off and have been dropping somewhat mysteriously, some researchers believe it's to do with changes in rice farming practices in Asia.

http://dotearth.blogs.nytimes.com/2011/12/14/methane-time-bomb-in-arctic-seas-apocalypse-not/

I consider Revkins advice to be good.

He mentions that one should not mistake science for what one gets from popsci articles, of course he makes this claim in a popsci article.

I tend to dismiss or leave unread such popsci fluff, including Revkin's.

 

[Piggy]

Andy Revkin has an interesting piece on this story, the researchers he spoke to say it's likely that we are just discovering more of these vents rather than that there are more appearing. Over the last decade methane level levelled off and have been dropping somewhat mysteriously, some researchers believe it's to do with changes in rice farming practices in Asia.

http://dotearth.blogs.nytimes.com/2011/12/14/methane-time-bomb-in-arctic-seas-apocalypse-not/

Thanks. I sure as hell hope that's true.

 

[CapelDodger]

What begs the questions of why there is some sort of a "debate" in this thread and why somebody is saying "sea level dropped lately" and other is pointing to the right reasons for it in a context of global warming.

I think it's worthwhile explaining why this particular observation is unremarkable in the context of AGW. Not everybody is uneducable, after all.

The right reply for "sea level dropped lately" is "yes, we are currently in a period of global warming" and/or "how do you believe such a fact relates to a no-warming long-term trend", and let them hang themselves from their own tongue.

I'm not above playing "Gotcha!" myself (far from it), but it's not really educational. If the commenter goes quiet and then pops up with the latest from WattsUpMyButt down the line we'll start to get a picture of their thinking, and soon enough the "latest final nail in the coffin" will be sea-levels dropping again, at which point the picture beomes pretty damn' clear.

It's as simple as caring and educated people who find a flaw in a theory do pounce repeatedly on the same point by means of a strong and consistent argumentation until the theory falls instead of throwing everything they find to the wall in the hope that something will stick. Who said "the seal level dropped lately" had half his/her job done just by getting a reply as if that fact challenges a global warming trend.

If a point really does challenge a global warming trend we should (as sceptics) pay attention to it.

Everybody should stop providing free completion for what are just half-baked layman-like short remarks, because who answer such questions are the ones who are providing the challenging part for free.

That simply leaves denier sites to occupy the first few pages of a Google search. I like to think we're not only here to joust with deniers, fun though that is (we have longer lances and heavier maces, and yes, Trakar, I do mean you ).