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PatrickLogicman

Hi, Neven. I just found out how to correct the user name. Can't find how to change the image. I would be grateful if you could copy my image from science20.com in case I find time to comment more.

http://www.science20.com/the_chatter_box

Jeff Kuper

Hey AnotherJourney,

You wrote:

"Denialists were right, for all intensive purposes, in mocking the IPCC REPORTS-"

I know if I were in your shoes I would want somebody to correct me if I were using a common phrase incorrectly. Anyway, the phrase is actually for all intents and purposes.

Cheers!

viddaloo

Neil, please stay and share. Resistance is inevitable at this point, and I think you know it will be hard to keep you gob shut during these coming exceptional events and developments. I value your voice and I'm sure many others do.

Robert S

P-maker: Yes, staying and fighting is so important. We may be going to "lose" - fail to keep warming below 2 degrees C, or some other limit, but even if all of our efforts only make a tenth of a degree difference, we're likely headed into a place where a tenth of a degree equals a million lives...

VaughnA

"I'm just going to sit back and watch now. It should be quite interesting to see how the chartic curve ends up by January."

NeilT, I hope you keep posting. I find your insights important to combat the "stupidity" in my world. I have several converts and I am working on some more. Your help is greatly appreciated.

Patrick, good to hear you are posting again!

viddaloo

FYI: Jaxa extent just lost 47 000 km², and is now 759 000 km² lower than the closest year (2012).

Jaxa volume recently dropped back to Mid–Sep levels.


[Click for full–size.]

Hans Gunnstaddar

Hey, NeilT is right - 2017 is baked into the Arctic cake. No amount of fight back against denial will change this next melt season. The 5th year in the repeating 5 year cycles (unless something happens to break the cycle), the big Kahoona, the drop down past 2012's record and how much we don't know yet, but from looking at viddaloo's latest chart, 2017 will likely have a huge head start.

Once that new low is presumably hit, it will interesting to crunch the numbers and work out the projected following 5 year cycle.

litesong

Yes. I've been thinking about an open letter on climate change to the President Elect, but I'm not sure drawing it to his attention would be a good thing. Posted by: Kevin McKinney
//////
Yeah, swearing isn't a good political maneuver!

litesong

2015 & 2016 set early year Arctic sea ice extent lows, equal to the ADDITIONAL LOSS of Alaska plus Texas-sized square kilometers! These early year ice lows were important because the sun was at its highest elevation in the sky. Huge amounts of solar energy were water absorbed which otherwise would have been ice reflected back to space. Tho most of the present High Arctic heat arrived from the south on excess AGW energy warm fronts, most certainly some of the excess solar absorbed energy is contributing to present ice forming retardation. What may be an even greater effect for future years, wherever there were downwellings in those Alaska plus Texas-sized waters, excess AGW generated solar energy was conducted to continental shelves or into deep Arctic Ocean waters for long term storage. Of course, that stored energy will make its vehement appearance sometime in the future.

litesong

Along with the outrageously high anomalous temperatures, is the width of days of temperatures above the "average". Two+ years ago, High Arctic temps remained above "average" for 140 straight days. At the very end of 2015 into 2016, High Arctic temperatures were above "average" for 150 days. During 100 straight days of that period, temperatures were no LESS than 3degC above average & at times, 11degC above "average". Previous to these periods, High Arctic temperatures were above normal for 100 days & nearly so. The "average" High Arctic temperature line doesn't refer to High Arctic temperatures BEFORE High Arctic AGW warming had already started. The "average" High Arctic temperature line is already elevated due to excess AGW heat already in the bio-sphere in the years 1958 through the present.

Hans Gunnstaddar

https://robertscribbler.com/

Nov. 18th latest R.S. post on Arctic high temps. & record low extent.

AnotherJourneybyTrain

Ha, thanks Jeff: yeh, listening to too much iron maiden plays tricks on me at times!

I'm just glad that temperature graph from dmi is going down at last.

viddaloo

Average JAXA ice thickness of the pack is now 0.66 meters and record thin. Volume at 4.3 thousand km³ also record low for the date.

PatrickLogicman

The current anomalous warmth in the Arctic will make itself felt in spring. In the days of sail the thick sea ice would get ever colder in winter and needed to rise by many degrees to reach 0 deg.C. The closer the temperature of the ice is to 0 deg.C, the sooner it will begin to melt in spring.

Current temperatures will almost certainly mean a fast melt onset in Arctic spring.

“It’s about 20C [36 degrees Fahrenheit] warmer than normal over most of the Arctic Ocean, along with cold anomalies of about the same magnitude over north-central Asia,” Jennifer Francis, an Arctic specialist at Rutgers University, said by email Wednesday.

“The Arctic warmth is the result of a combination of record-low sea-ice extent for this time of year, probably very thin ice, and plenty of warm/moist air from lower latitudes being driven northward by a very wavy jet stream.”

Source - Washington Post Nov 17.

"there is no current explanation for the heavy chill in Siberia, amid fears that it could be used by climate change deniers as a counter-argument to stop steps that could be taken to address global warming."
Source - ibtimes.co.in Nov 19

If the 'hot pole - cold siberia' trend continues it could lead to an enhanced siberian 'pole of cold'. I wonder if it is possible that a more open Arctic ocean could lead to higher precipitation in Siberia. Perhaps a few consecutive years of snow over a wide area which does not melt in summer could trigger a new ice age? Who knows?

How an ice age begins.

A drop in average temperature in a northern latitude (e.g. siberia) means that snow does not melt in summer. As the snow pack grows, the bottom layer turns to ice. Year on year the volume of ice grows and flows. The albedo feedback stabilises the 'pole of cold' and the glacier grows unchecked.

Hans Gunnstaddar

-'pole of cold'
-higher precipitation in Siberia
-a new ice age
-drop in average temperature
-snow does not melt in summer
-snow pack grows
-volume of ice grows
-glacier grows unchecked
-denial grandiose fantasies blossom


Innovabo

Has there ever been a situation before where Arcic sea ice extent has *decreased* in mid november??
http://nsidc.org/data/seaice_index/images/daily_images/N_stddev_timeseries.png

PatrickLogicman

@Hans "denial grandiose fantasies blossom"

You can take that to the bank.

Recommended read -

President Elect Trump - Why Climate Change Is No Longer A Political Issue Outside The US
http://www.science20.com/robert_inventor/president_elect_trump_why_climate_change_is_no_longer_a_political_issue_outside_the_us-180675

Don't miss video - "The Age of Stupid" in the comments below the article.

Werther

[IMG]http://i1036.photobucket.com/albums/a446/hanver1/1000Mb%20Temp%20ano%201504%20to%2015092016_zpsxmffxti9.jpg[/IMG]

The current negative temop anomaly centered over the Eastern Central Ural Mountains is not as persistent as Arctic Amplification. It cannot be seen as a sort of compensation.

Look at the NCEP/NCAR mean for last summer season. Most of the region that is now experiencing -10 dC anomalies had a +2-+3 dC summer.
It is a temporary feature. Driven by weather.
Arctic Amplification is not weather. It is a climatologic reality:

[IMG]http://i1036.photobucket.com/albums/a446/hanver1/1000Mb%20Temp%20ano%200101%20to%2018112016_zps9zt2ppff.jpg[/IMG]

The Siberian cold will pass. The AA will not. There’s not going to be a ‘new ice age’.

Temporary cold, yes.

It won’t last.

GHG forcing is dominant now…..

viddaloo
Has there ever been a situation before where Arcic sea ice extent has *decreased* in mid november??

The short answer is yes, it happened as late as last year.

The longer answer assumes the inclusion of the words "this much" in the question, and for JAXA extent's sake, no precedence exists since at least 2002.

wayne

Kudos to all who commented on sad state of sea ice Patricklocicman

I would add

http://eh2r.blogspot.ca/2016/11/dispersed-emaciated-heat-diminished-sea.html

The main reason why Arctic Ocean surface air is so warm is because of the myriads of leads. Changing the nature of the lower troposphere to be mainly adiabatic. Encouraging incoming warm cyclones which would have otherwise warmed the Urals. It is a feedback loop dominating weather throughout much of the Northern Hemisphere. It is naturally colder over the continents when cloud free, so if the cyclones from the Atlantic go to the Pole, someone in Russia is missing the warmth from clouds.

Wayne Kernochan

I want to delurk to comment on a few things mentioned in this thread. First, Hans thinks that sea level rise will revert to 4 mm/year from the late-2014 to early-2016 10 mm/year.

I question that. It seems to me that melt, and therefore sea level rise, is a function more of the level of global warming (now 1.2 degrees C) rather than the rate of growth of global warming. If you look at 1998 to early 2013, the global temperature level was at least in the same ball park at start and end. Global temps are now far above that, and no one thinks they'll return to the levels of 1998- 2013 again -- especially since CO2 mauna loa continues to rise faster than ever. So I conclude that the "new normal" is likely to be closer to 10 mm/year than 4 mm/year.

Btw, 10 mm/year takes us to just about 3 feet of sea level rise by the end of this century. And does anyone think the rate won't increase?

Wayne Kernochan

2nd comment: about the CO2 rise (Mauna Loa) some commenters have noted. Here's a summary excerpt from my blog (waynekernochanblog.blogspot.com): "Let’s start with the CO2 rise that I have been following since early this year.  The “baked in” (yearly average) amount of CO2 has reached, effectively, 405 ppm, as of October’s results about 1 ½ years after it passed 400 ppm permanently.  More alarmingly, the surge caused at least partly by el Nino is not going away.  I have been following CO2 measurements from Mauna Loa for about 5 years, and always before this year the 10-year rate of increase has been a little more than 1.0 ppm per year.  The el Nino and follow-on has added almost 3 ppm to that rate, making a rate of almost 1.1 ppm per year.  And the new rate of increase shows little signs of stopping, so that we can project a rate of 1.2 ppm within the next 5 years -- a 20 percent increase."

But what is really alarming to me is that the rate of rise of CO2 Mauna Loa has dipped very little after the el Nino ended -- unlike 1998, which saw a sharp drop in rate in 1999 and 2000. This raises the question of whether the "lag time" between CO2 rise and global temp rise is shorter than we thought (i.e., CO2 rise is helping keep global temp rise going) -- at least in these circumstances. And, of course, if the CO2 rise does lead to temp rise sooner rather than later, then the Arctic temps and sea ice will see the greatest impact...

Wayne Kernochan

3rd comment: Some commenters have noted that the CO2 equivalent of all greenhouse gases now is estimated at 483 ppm plus. I would be careful with that figure, as when we talk about non-CO2 greenhouse gases in 1850 compared to today. So it's not that other greenhouse gases add 78 ppm to the greenhouse effect; it's that they add 78 minus whatever the level of those gases was in 1850. In the case of methane, at least, we know the level was significant in 1850, since today's naturally occurring methane emissions is about equal to man-caused methane emissions (according to a 2007 article quoted in this blog a long while back). I would swag about 2/3 of 78 ppm is the actual rise, or 52 ppm.

However, imho, it is true that as Hansen and others have argued, the net effect of CO2 atmospheric doubling is more like 4 degrees C than 2. We see other greenhouse gases rise in proportion, adding one increment to global warming; we see changes in albedo adding another, by storing more heat at the earth's surface.

Hans Gunnstaddar

"Hans thinks that sea level rise will revert to 4 mm/year from the late-2014 to early-2016 10 mm/year."

I didn't write that. It's best to quote someone if you are going to attach their name to something written. If you go back and find a specific quote of mine and paste it into a new post, I'll be happy to reply.

Hans Gunnstaddar

"President Elect Trump - Why Climate Change Is No Longer A Political Issue Outside The US."

P. Logicman, I am aware of that. Really seems like the worst timing to be just now starting what will either be 4 or 8 years of denial at the US prez level. (had been hoping for Hillary to go all in on renewables).

So glad my wife and I went to Italy this past Spring, because we might not be so welcome now. We had gotten a ride to an Italian Air Force museum next to a lake just outside Rome by a client, Allesandro, and the topic of Trump came up. We assured him there was no way he could win and we all had a good laugh. Not so funny now. What's ironic is there were many displays at that museum of art from the fascist time period of Mussolini.

Sam

Wayne,

Calculating CO2 equivalent (CO2e) is far from trivial. And though the result has some use, it obscures the immense complexities involved in heat transport across the IR spectrum and through the atmosphere.

With that caveat out of the way, CO2 heating is approximately logarithmic with concentration. The way the value is calculated is by using a set of observed correlation factors to convert CO2 and other gas concentrations to equivalent forcings in watts/meter^2. This includes a couple of compounding factors between CO2 and methane and N2O. As it turns out, these are negligible. After you sum all of the forcings, including effects on water vapor and ozone, you then back out the CO2e through the logarithmic relationship.

If you take the preindustrial gas levels (278 ppm CO2 etc...), the preindustrial CO2e was about 378 ppm CO2e. If you take the past years average for all of the major gases (CO2, CH4, N2O, resulting water vapor changes) and then add the ozone change (very minor) and the top three dozen trace gases (HCFCs, SF6, NF3, etc...). The current CO2 of 402.5 (annual global mean) etc... you get a grand total of 520 ppm CO2e. That then converts to a thermodynamic temperature change from preindustrial due to these gases of 1.03 C.

Doing the calculation is an interesting exercise. There are clearly missing factors. The elevation of moisture into the high atmosphere leading to increased warming, and the cooling from sulfate and particulate aerosols are probably the largest. Then add stochastic variation and even as a simple model it all gets rather complex.

If you then extrapolate the observed trends on all of these gases through 2070 (the date isn't important) a couple of things jump out.

First, CO2e can be approximated as 1.38 * CO2.

Second, the trace gases (chlorofluoro yada yada) amount to about 10 ppm (I.e. small and nearly constant).

Third, even though the temperature rise attributed to these gases is exponential, it can reasonably be approximated through late in the 20th century as [CO2]/278ppm - 0.45 C. The actual rise is considerably higher for the reasons noted above, plus immense changes when the atmospheric and oceanic changes kick in.

Fourth, this is a very simple model and does not account for a variety of huge factors. It only gives an idea of the direct impact of the warming directly. In other words - use caution - there be dragons here.

Fifth, we are in deep trouble already and we are toast by mid century. We must all simple stop burning things and stop all emissions of carbon gases (principally CO2 and methane) and the consequent N2O.

I encourage everyone interested to research the complexities and run the calculations yourself. As you do so, a huge array of questions and challenges will become apparent. Mostly these boil down to how little we actually understand the immense complexities involved in the earth's energy balance.

It also becomes quickly apparent that many of the relied upon estimates (EEA) shouldn't be relied upon at all.

Sam

Oops CO2e runs about 1.30 to 1.38 * CO2.

Al Rodger

Wayne Kernochan,
Concerning your second comment. I am surprised by what you say. I too follow MLO CO2. The one exemplar we have for a strong El Nino affecting CO2 levels is the 1997/98 event. The weekly data if smoothed by say averaging over a 5-week period show clearly that the increase in CO2 levels over the 1997/98 El Nino peaked in early October 1998 and dropped down from that peak level over the following nine months or so. The decline is not smooth but bumpy.

This 2015/26 El Nino saw CO2 rises peak in June, earlier than in 1998. The peak was a higher level (roughly +0.3ppm). We perhaps should expect a slighly larger margin with emissions being in excess of 2Gt(C)pa higher than in 1998 & an atmospheric fraction of 0.4. The rise in annual CO2 levels is now reducing bumpily, down from June's 4.0ppm.pa to 3.3ppm.pa in October. Give it time. Let the bumps come and go. By mid-2017 we will see a more representative rate of increase.

And concerning your third comment, the concept CO2(eq) is really designed to allow decision-making within climate change mitigation, allowing the effort to reduce one GHG to be gauged against the effort to reduce another. Do not use CO2(eq) to calculate resulting global temperature rises, certainly not in the manner you (& Sam) describe. The pre-industrial levels of non-CO2 GHGs would be solely used to calculate the forcing these non-CO2 GHGs add, forcings which allow a straighforward calculation of the resulting warming. CO2(eq) is the CO2 level that would cause such a forcing. The pre-industrial CO2(eq) is simply not part of the calculation.

PatrickLogicman

Here's a great overview of the facts about cllimate science with a huge number of links out.

In post-election media, colorful thread develops on science—mainly climate science
http://scitation.aip.org/content/aip/magazine/physicstoday/news/10.1063/PT.5.8196

It could take you a week to follow all those links, but if you can only spare half a day you may like -
http://www.science20.com/the_chatter_box/blog/back_to_square_1_first_steps_in_climate_science-180677

Wayne Kernochan

Hi all, so much to reply to! I thank you all for informative replies, which should keep me busy until the next kidney stone hits :(

I'll try to respond to a few here. (1) Absolutely right, Hans, my profuse apologies for a lousy memory in a post done in haste. It was NeilT, while Bill Fothergill's comment seems more in line with what I was suggesting above.

(2) With regard to CO2(eq), actually, I am not calculating (direct) forcing from CO2(eq) at all. I am referring to a Hansen et al paper in which he points out that in past major CO2 rises (55 million and 250 million years ago) the ratio of CO2 rise to global warming appears to be 4 degrees C per doubling, rather than the 2 degrees or so we would expect from CO2 alone. He then conjectures why this might be so -- primarily "other greenhouse gases" and change in albedo. So I am in fact using this to approximate the long-term effect of CO2 rise in the long term, while postulating that much of this will happen in the medium term and that "other greenhouse gas" rise will be proportional to CO2 rise in the medium as well as the long term.

With regard to CO2 Mauna Loa: I am relying on the monthly figures. In these, peak CO2 rise is in April of this year -- yes, I recognize that 1998 peak is different under those measures as well. But if we look at 1999 yearly rise, it has dropped a full 2 ppm to 0.93. Thus, the end point of (as you say) a 9-11 month descent might be about 1 ppm. Personally, given that we are through the bulk of last year's Oct.-Nov. rapid rise, and that Dec.-Feb. were relatively slow-growth months, I'm betting on monthly rise rates well above 3 ppm until Mar., and therefore we will be in the 3.5 ppm ballpark until March (after which, who knows?) Again, this does not strike me as "normal".

I guess what I'm saying in the above is that I am less wrong than you think and we are more in agreement than you think :)

Sam

Al,

I agree with you that it is inappropriate to use CO2e as the be-all end-all for calculating temperature rise. It is all to easy to fall into that trap. As Wayne points out from the work so many hard scientists have done, there are other effects that are more important. If one relied only on CO2e the indicated temperature rise would greatly understate the real temperature change.

Hansen and others have pointed out the strong correlation between CO2 rise and temperature rise and how much larger that is than would be predicted from the simplest assessments and thermodynamic calculations.

A large part of these effects seems to be from a group of combined effects from the increase in moisture and clouds in the atmosphere, the heightening of moisture into the high atmosphere and albedo changes.

I suspect too that differences in these changes with latitude are large and that the changes in the polar regions are very much more important than equatorial changes for example.

Though CO2e does allow for relative comparisons of the effects of the various warming gases and maximizing what good we might do, it easily misleads as well by missing these larger impacts.

What became really clear to me in doing the research to do the calculations for myself was that the minor gases (gases other than CO2, CH4, N2O and H20 as gas and as clouds) have essentially a constant and quite small impact on the outcome. Yes, it is very important to limit all of these. In the grand scheme, the only two we must focus on are CO2 and CH4.

Both of those come down to stopping the use of fossil fuels. If we fail on this all of the rest are irrelevant. And we are badly failing on those two.

If we globally somehow turn the corner (immediately) on CO2 and CH4, then the others might become important, otherwise they are of minor significance. But we are not going to turn the corner on CO2 or CH4, so that is moot anyway.

Sam

Al Rodger

Wayne Kernochan,
Just sticking with the CO2 growth....
Of course, time will tell what levels of CO2 growth will drop to soon enough. However, a view that CO2 growth will remain a 3.5ppm.pa until March 2017 is a long way from my own assement.
Do note that the 0.93ppm/yr figure given by NOAA MLO data for 1999 is the CO2 growth over the year (Ave.CO2 Nov99-Feb00 minus Ave.CO2 Nove98-Feb99) and so strongly impacted by the La Nina conditions that had appeared immediately afrer the 1997/98 El Nino. (This time round, the La Nina is not anything like as strong, but a short and weak La Nina that will be replaced by neutral conditions by early next year.) The weekly data provided by NOAA shows annual CO2 growth remained above 2ppm.pa until week 20 of 1999.
I do recomment using the weekly data to those assessing CO2 growth.

Al Rodger

Sam,
The mechanisms being described as "slow feedbacks" by Hansen et al (2013) are the result of changes in albedo & GHGs, both resulting from melting of the chryosphere & vagitation change. As the name says, they are slow and they are feedbacks and will precipitate their own fast feedbacks (when/if they were to occur). Hansen et al (2013) cites papers suggesting the present level of global temperatures give a 30%-50% increase on warming due to slow feedbacks. This increases to 100% if warming moves to an ice-free world as per 35 million years ago. I interpret the message being given as saying that we are prodding a beast that can be very dangerous and that we do not entirely understand. Our continued CO2 emissions are an extreme folly.
Were this not Neven's Arcic blog, I would spend a little more time considering the content of this comment but I feel we are now addressing quite broad subject-matter that is not cryospherical in nature.

Sam

Also,

As I noted previously, one of the things that jumped out at me in doing the calculation myself (and redoing it many times) is that we are at 520 ppm CO2e now. This is much higher than the numbers reported elsewhere. I am somewhat anxious for someone else here to independently grind through it all to compare notes in order to find any errors I may have made. If we are indeed at 520 ppm CO2e, then the situation is substantially worse than is generally recognized.

With the political and institutional pressures the major organizations face to iron clad prove every iota of information (or be forced to exclude it) it is not surprising for the published estimates to be very nonconservative (understating the seriousness of our condition).

Also, if we take the preindustrial contribution of methane and use it instead of current methane, we get a somewhat higher relative equivalent CO2(re) of something like 435-450 ppm. What that number shows is not the combined effects, but rather what the CO2 alone would need to be to get to the current CO2e with only CO2 and preindustrial CH4 levels. And what that in turn shows is that the gases other than CO2 are all of relatively minor importance.

The huge caveat with that is that if we emit the carbon from the tundra stores or the oceanic methane clathrates that that dramatically and suddenly changes. In those cases, methane becomes immensely important.

More than all of this, what these calculations hide is the most important big picture. They all inherently presume a regularity and quasi linearity to how the system responds to heating. That is nearly true for small changes.

That is decidedly false for large changes. Once large changes occur, the base conditions change and the calculations lose relevance. And it is here that the paleoclimatic correlations take on huge significance.

But that too is deceptive as it is based on the quasi stable climatic conditions the earth has been in for many millions of years with two ice covered poles. It is relatively rare in the long history of the earth to exist in these quasistable midregions between snowball earth and hothouse earth.

The change we are driving now looks to most definitely eliminate the northern ice sheets. That will likely create then an unsymmetrical atmosphere with a unicellular northern circulation and a cloud covered warm northern pole; and an ice covered (though melting) Antarctic pole with a three cell atmospheric circulation in the Southern Hemisphere.

The earth existed in those conditions for tens of millions of years. So, it might be stable enough that we could return to near present conditions in a few million years. That is provided we do not push the earth so hard that we release the tundra carbon stores and:or the oceanic clathrates. Should those occur, the heating may be prolonged and serious enough to fully melt Antarctica.

If that happens, we enter a hothouse earth. Temperatures bang up to the top end of the geologic scale and limit out there. The atmospheric pressure rises and the O2 content falls leaving an atmosphere that won't support large animals. In time that too changes and O2 soars to the point that forests can occasionally burn during torrential downpours and three foot spiders roam the earth.

Any of those are conditions we should not want to explore. Agriculture will likely become impossible in the northern hemisphere at least during the transition to a unicellular atmospheric circulation system. We won't be able to predict temperatures or rainfall from year to year. Catastrophic variations from jet stream movements will make that even worse.

Once things stabilize in the unicellular flows, we might again get to some sort of predictable system for crops if we are very fortunate. However, the changes in oceanic circulation may take a thousand to several thousand years to stabilize. In the mean time, large anoxic areas may form with large atmospheric and continental consequences.

Are any of these provably true. I don't know. They are likely true, and equally likely unprovable. We lack the data. The danger from them to human survival is so large it would be unwise to roll the dice and find out. But roll the dice we have. So, in time (perhaps not too much time) we will find out.

Al Rodger

Sam,
As a check on your calculations, you may find this CDIAC webpage useful. It is updated with 2015 GHG concentrations & the various GHGs listed total to 527ppm CO2(eq). I should repeat that CO2(eq) values are a poor substitute for more detailed modelling of the consequences of our GHG emissions.

Sam

Al,

Thank you! I don't know how I missed that source in my search. There are some small differences in factors that appear to account for the 7 ppm difference between their estimate and my own. That's not a lot considering all of the factors involved.

Very helpful. Thanks again.
Sam

VaughnA

Sam, NOAA has CO2eq at 485 ppm at the end of 2015. They also may use slightly different data values than CDIAC which could explain some of the difference. NOAA also does not include tropospheric ozone which looks to be most of the difference. This is reasonably close and supports what you are saying. This does not include water vapor either which has also increased some. I believe the 520 or 527 ppmCO2eq sounds reasonable.

http://www.esrl.noaa.gov/gmd/

Bill Fothergill

@ Vaughn "... This does not include water vapor either which has also increased some... "

Owing to the way its Partial Vapour Pressure is exquisitely temperature dependent, water vapour is usually (invariably?) considered as a condensing greenhouse gas. For that very reason, it is normally treated as a feedback, rather than a forcing agent in its own right.

As a consequence, I wouldn't expect to see a CO2eq mentioned in the ESRL or CDIAC tables - unless accompanied by an explanatory codicil to that effect.

VaughnA

Thanks Bill,
I was wondering why water vapor was left out. What you say explains that.

NeilT

Thanks everyone who would like me to keep posting. I will do but I'm not sure how much this freezing season.

Right now I'm a bit more fixated on how a repeating pattern of delayed re-freeze seems to happen around once a decade. Which also maps into 2006 and 2016. 1996 looks similar but much more muted but of the same type. Chartic has been brilliant for being able to see this.

So I'm just looking at 2016 to see how it ends up but I'm pretty certain it's going to be a long delayed re-freeze with a record low start into 2017. That's going to have a massive impact on the 2017 melt. If it also gets the good weather, then it's going to be seriously low.

Yes I did say that I expected the 10mm to come back to something like 4mm then slowly increase. I still recall the "shock" drop in sea levels by 6mm, only to have that 6mm loss fall back to earth inundating some countries. However it trended back to the norm after the blip. I can't see that this will be sustained as there is not, yet, enough heat to sustain it.

My take is that we have a cooling budget which we are burning. We just burned some of it. Some will, of course, come from oceanic expansion due to warming. It is no surprise that two years after Wunderground had to lift their charts from a max of 32C to a max of 35C that we see more expansion.

However if much of this rise is landfast ice, it will have had a twin effect. One in that it is a cooling force entering the sea, second that it will have brought the system more back to the norm. At a cost of irreplaceable ice which is our planetary refrigerator.

It's like a freezer with limited coolant. Once you've burned all the coolant it's going to warm up pretty fast.

That is the reasoning behind what I said.

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