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Comments 47951 to 48000:
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Smith at 10:04 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Tom Curtis@60 - Thank you for your response.
For that he is rightly criticized.
Fair enough. The label "Denial Fake Trend" just seems like odd language IMO.
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Smith at 09:59 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Dana1981@34 - Thank you for your response.
I hope you're not holding me to a higher standard than you're holding Wattsy.
I guess the short answer is yes I am. Wouldn't you prefer it that way?
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scaddenp at 09:34 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
'I am still under the impression that the above is not true." Correct. Kevin is wrong. He is effectively posulating that coductive heat transfer from atmosphere to warm the surface or ocean. This would be a violation of 2nd law. Instead, the GHG gases in the atmosphere increase the amount of LW radiation reaching the surface. (This is measurable). Kevin, I would strongly recommend looking at Science of Doom's excellent basics on this. Not getting this right is leading you into confusion.
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Tom Curtis at 08:11 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
smith @19 and @29, there are several acceptable ways to highlight a data of special interest in a graph. Two common methods are to draw an ellipse around the data of particular interest, or to highlight a large rectangular region including all the data of special interest. A third way is to highlight the values on the x-axis that are of interest. The common feature of all these methods are that they cannot be mistaken for a trend line. Equally important, nor do they create an optical illusion suggesting that the trend in the data is flatter than it actually is.
Instead of these common conventions, Watts chose a method to "highlight" the data of interest which is easilly mistaken for a trend line, and which is likely to suggest the trend is flatter than it actually is.
More importantly, if you intend to show that there has been a pause in the trend, the minimum method is to show calculate the trend line for the data exhibiting the trend, and to calculate the trend and confidence interval of the trend for the period supposedly exhibiting a pause, shoing that the confidence interval of the trend does not include the long term trend. Further, you should show the supposed pause is not over a period so short that its trend does not fall withing the 3 sigma distribution range of trends of that period over the course of the long term trend.
Instead of that, Watts chose to ignore that necessary legwork; and to display a line that was both easilly mistaken for a trend and likely to distort visual estimates of the trend. For that he is rightly criticized.
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KR at 07:26 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Kevin - In addition, those empirically observed changes in TOA radiation would have to reverse in order to remove a greenhouse gas induced energy imbalance; and they have not.
What has happened over this cherry-picked interval is that 1998 was a 3-sigma extreme El Nino, followed by a number of La Ninas. If you correctly account for these short term variations (Rahmstorf et al 2012, also a simpler analysis by John Nielsen-Gammon), it is clear that the warming trend continues just as expected from the physics.
On the other hand, if you select extreme points in the noise such as 1997/1998 and claim trend changes, you are cherry-picking from statistically insignificant data. Which means that you are wrong to make those assertions.
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KR at 07:15 AM on 8 March 2013What doesn’t change with climate?
helenavargas - There is work available on Earthshine under Goode et al 2001, Rodiguez et al 2005 (not a reviewed paper), you can check their methods and sources (ISCCP datasets, solar observatory readings, etc). I believe that uncertainties with this technique are thought to be fairly high, although I can't locate those discussions right now.
RE: IR to space, the Earth is a 'graybody' with a highly notched spectra, emissivity of ~0.612, although the spectra is compared to an integrated blackbody spectra for a blackbody equivalent temperature. The climate is anything but adiabatic - it is not thermally isolated, it is a system with a constant inflow and constant outflow of energy, somewhere near dynamic equilibrium. The current divergence from equilibrium, leading to global warming, is indicative of a long-term 0.8 W/m^2 imbalance (from ocean heat content changes). But equilibrium will not be reached until (a) forcing changes halt, and (b) enough time has passed for the thermal inertia of the Earth to catch up.
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Rob Honeycutt at 07:03 AM on 8 March 2013What doesn’t change with climate?
hellenavargas... Not sure why it didn't work for you. Will put it by our resident expert.
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Composer99 at 06:45 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Kevin:
That - showing that the top-of-atmosphere radiative budget is in balance - is exactly what it would take to show that global warming has stalled.
The radiative energy imbalance at top-of-atmosphere is a phenomenon empirically measured by satellite. It's not "theory" that can be overruled by "data". Furthermore, it's the reason surface temperatures are increasing in the first place.
Several people have now very patiently explained the problems with your reasoning. I note that your response is to indirectly complain of "political correctness" and to re-assert your claim without any apparent attempt to correct your misconceptions of statistics or physics.
Moderator Response: [DB] All parties...and most especially Kevin, please take the discussion of "16 years" to that most-appropriately-named thread. If it is deemed to have already been covered there, it will be adjudged as sloganeering and be moderated accordingly. Thanks in advance for everyone's compliance and understanding in this matter. -
helenavargas at 06:37 AM on 8 March 2013What doesn’t change with climate?
Apologies for the HTML not working in my post #6. Hope its intent can still be read.
If 'source' input isn't seen as source, what have I missed??
tx --bc/hv
Moderator Response: [RH] Voila! -
helenavargas at 06:33 AM on 8 March 2013What doesn’t change with climate?
Folks -- Where can one find a 24-h-averaged, (α,β)moon-averaged visible spectrum of sunlight reflected by the earth incident on the moon? By now, someone will have calculated model-dependent predictions of such spectra, so your statements about temperature changes on the lunar surface -- which endures month-long 'days', of course -- might have data against which to be checked. Would like to be able to visualize what a warmed earth would look like from space, other than cloudier. Having spent decades in the JHKL part of the NIR spectrum, I'd like to see a 'bluer' = visible representation of future reality.
KR (#5): Technical question: isn't the change in equilibrium sufficiently small (δT/T over time) more or less adiabatic, preserving the blackbody nature of the earth's climate? Naively, it would seem tough to do the physics otherwise.
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DSL at 06:26 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
And Kevin, you still don't get it: the theory of anthropogenic global warming is not based on the surface temp trend. It could be plummeting, and CO2 would still be doing its thing. What you need to focus on is not "global warming" but "model projections." You are not going to falsify the greenhouse effect, and, yes, I'll put money on it.
You continue to look for a simplistic sound bite: "global warming has stopped." What we're really talking about here is "global surface temp has flattened in recent years; there are several factors that could be driving this, and there are scientists focused on these factors." No one is investigating whether or not CO2 has stopped working.
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scaddenp at 06:21 AM on 8 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
And just a further point on CO2 and glacials. While Milankovitch forcing pace the glacial cycles, there wouldnt be any glacial cycle if CO2 concentration was higher. The milankovitch forcings were still there before the Quaternary. Its just that CO2 was too high before that for them to significantly affect planetary albedo.
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DSL at 06:20 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
16 years, Kevin -- very intentionally.
If you find me evidence for your last assertion, I just might believe you. As far as I know, very few sensitivity studies are based on the recent surface temp trend, and none of those conclude high sensitivity.
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Roger D at 06:11 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Kevin, I was questioning whether this statement of yours is true:
As I stated before, AGW (removed the C) states that the warming originates in the atmosphere. If it slows, halts, increases, stops, starts, whatever, here, it will then and only then, continue on to the oceans, starting with the upper layer first. Regardless of whether there is an energy imbalance or not, it the temp increase stalls in the atmosphere, that will dictate a stall in global warming.
I'm still under the impression that the above is not true. At your comment #54 you say that global warming can have said to have stopped if there were to be 30 years of no warming trend (in the surface temperature trend I assume) even if there was evidence of a continuing energy imbalence. From what I think I understand, with a continued enegy imbalance, as expected from the relativley steady rise in GHG, the surface temperature trend is expected to do what it has done in recent decades and get back on a significantly upward trend. So OK, I get your point that if this doesn't happen then there is something amiss with the theory of AGW. But it seems unlikely to me that as you put it, this hypothetical "scintific method -data overruling theory type of thing" will be realized. I'll leave it to others that are more knowledgable and articulate on this topic than myself to say more if they are inclined.
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KR at 06:10 AM on 8 March 2013What doesn’t change with climate?
Changing greenhouse gas concentrations causes an energy imbalance between incoming/outgoing energy.
- More GHGs reduce total outgoing IR at all temperatures (reducing outgoing energy)...
- That difference between incoming and outgoing accumulates, warming the climate...
- Until, at a higher climate temperature, the Earth is once again radiating as much as it is receiving.
There are indeed frequencies in IR that have increased with current warming. But if you integrate energy over the entire IR spectrum, the sum of outgoing energy is presently lower than incoming. The final at-equilibrium IR spectra of the Earth, under increased GHGs, will show warmer peaks but a more jagged outline, integrating to the incoming 240 W/m^2 from the sun.
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truthisbest at 05:50 AM on 8 March 2013What doesn’t change with climate?
This statement doesn't quite accord with my layman's understanding:
"...before climate equilibrium is reached, the outgoing radiation from Earth would be reduced..."
I understood [or thought I understood] that a warming planet will omit more Long Wave radition into space except at those wavelengths trapped by the GHGs and that this can [perversely] mean that even as more Long Wave radiation to outer space is inhibited by GHGs the overall level of non-inhibited radiation can increase the total OLWR.
I shall be grateful if a better Scientist than I can confirm or deny my understanding or [gently] point me in the right direction.
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Kevin8233 at 05:41 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Roger D,
Please re-read what I wrote. You are not paraphrasing it correctly.
(-snip-).
(-snip-). That is the extent of that particular point.
DSL,
How long of time frame was the 2007 rate calculated on? Was it 16 years? 27 years?
And yes, some scientist did believe it would persist, or we wouldn't have heard of the 2 - 6 C increase predictions.
Moderator Response: [DB] Sloganeering snipped. -
DSL at 05:30 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Kevin, you say: "At the current rate, after an additional 100 years, the temp will rise an additional 0.4 - 0.8 C. That does not seem that significant, and in fact will achieve the outcome of keeping the temp increase to less than 2 C."
Yes. At the current linear trend. Do you expect that trend to persist? In 2007, did you expect the .284C per decade trend to persist? You must have, or you're being inconsistent. Again, do you think scientists thought it would persist?
By the way, the current rate of warming is still 9x that of PETM event warming. There's significance and then there's significance.
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Rob Honeycutt at 05:25 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Those figures again.... I dropped the 2-sigma range and typed one of the figures wrong...
GISS since 1995 = 0.113 ±0.112 °C/decade (2σ)
GISS since 1973 = 0.166 ±0.037 °C/decade (2σ)
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KR at 05:24 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Composer99 - Actually, surface temperatures are more than adequate to judge warming.
But that's true if, and only if, you examine enough data for statistical significance, say 30 years worth or more. The "no warming since 1997" claimants such as Kevin fail in that regard.
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Roger D at 05:23 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Although it's been pointed out that total energy accumulation in the "system" is continuously growing, Kevin seems to be saying that an essentially steady global warming cannot be considered to be occuring because there are changes in trends that approach zero for he surface and tropsopheric temperature record.The response given by Composer99@ 37 addresses this.
Is there any physics-based reason to think that the oceans cannot continue to gain heat energy without the surface temps mirroring them? It seems like their shouldn't be, as longs as thre is water, ice, air, land to allow heat energy flow
(sorry if this question is in the too-basic catoagory)
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Dikran Marsupial at 05:11 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Kevin, you appear not to understand statistical hypothesis testing. If you want to make a claim (such as "the temp increase has slowed") on the basis of a set of observations, you need to show that the Null hypothesis, i.e. the opposite of what you want to claim (in this case "the temp increase has not slowed") and show that the observations are not consistent with that null hypothesis.
Hypothsesis tests are not symmetric, the lack of a statistically significant trend does not mean that there has been no warming, just that you can't rule out the possibility that it hasn't warmed.
The "margin of error" as you call it, also include the long term trend, so the observations don't rule out the possibility that warming has stopped, but they don't rule out the possibility that warming has continued at the same rate either. Hence you cannot draw the conclusion that you did on statistical grounds.
You would benefit from dropping the hubris a bit, and just consider the possibility that you don't understand the issue quite as well as you think you do.
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Rob Honeycutt at 05:10 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Kevin... You can't compare a trend that is not statistically significant with one that is and expect that you're revealing anything.
GISS since 1973 = 0.166/decade
GISS since 1995 = 0.116/decade
Both statistically significant. Both well within model projections.
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HK at 05:07 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Does it really matter if the surface or upper ocean warming has slowed down in recent years?
Figure 2 clearly shows that the ocean warming down to 2000 meters has continued unabated after 1997, 1998 or whatever year the denialists prefer to start from.
From 1997 to 2010 the oceans accumulated about 10 x 1022 J of energy, which is sufficient to heat the entire atmosphere by 20oC.The rate of warming was about 0.45 x 1022 J per year from 1966 to 1997 and 0.77 x 1022 J per year from 1997 to 2010, so the warming has in fact accelerated, not slowed down!
And the reason?
Definitely not the sun, since the present solar cycle seems to peak at the lowest level since the 1880s.
Maybe it's time to start listening to the scientists who predicted this warming many decades ago?
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Kevin8233 at 05:02 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Dikran, (41)
What has the warming rate been for the past 16 years?
Compared to the warming rate of the past 30 years, which is greater? By what ratio?
Do we really need to be this explicit?
Moderator Response: [DB] All parties...and most especially Kevin, please take the discussion of "16 years" to that most-appropriately-named thread. If it is deemed to have already been covered there, it will be adjudged as sloganeering and be moderated accordingly. Thanks in advance for everyone's compliance and understanding in this matter. -
Rob Honeycutt at 05:02 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Kevin @ 42... Wrong. That is a completely inaccurate statement.
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Dikran Marsupial at 05:01 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Kevin, please don't play games. What does the lack of a statistically significant trend actually mean in terms of what we can conclude about global climate from that set of observations?
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Rob Honeycutt at 05:00 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Kevin @ 38... If the trend is not statistically significant that merely means that that you have a noisy data set. It means you can't rule out a zero trend, but you also can't rule out a higher trend either, all at the 95% confidence level.
A trend that is not statistically significant means that you need more data. Once you go back far enough to get a statistically significant trend, what do you have?
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Kevin8233 at 04:59 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Dikran Marsupial,
It means that the statement "There has been no significant warming for the past 16 years" is accurate.
Moderator Response: [DB] All parties...and most especially Kevin, please take the discussion of "16 years" to that most-appropriately-named thread. If it is deemed to have already been covered there, it will be adjudged as sloganeering and be moderated accordingly. Thanks in advance for everyone's compliance and understanding in this matter. -
Dikran Marsupial at 04:58 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Kevin wrote: "What is important is, the temp increase has slowed"
The observations do not support that statement (at least not from a statistical perspecive). To assert that this is the case, you need to show that there has been a statistically significant change in the rate of warming, which you have not done.
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Kevin8233 at 04:55 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Composer99,
It would help if you respond to what other people atually write rather than resorting to quote-mining. Such behaviour is extremely disingenuous and frankly reflects poorly on you.
What/where are you referring to? (-snip-)Moderator Response: [DB] Sloganeering and excessive html snipped. -
Russell at 04:53 AM on 8 March 2013Did Murdoch's The Australian Misrepresent IPCC Chair Pachauri on Global Warming?
http://vvattsupwiththat.blogspot.com/2013/02/postmodern-geochemistry-semiotic-carbon.html
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Russell at 04:51 AM on 8 March 2013Did Murdoch's The Australian Misrepresent IPCC Chair Pachauri on Global Warming?
Murdoch's take on the subject requires<a href="http://vvattsupwiththat.blogspot.com/2013/02/postmodern-geochemistry-semiotic-carbon.html"> a new approach to the carbon cycle as we know it </a>
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Ari Jokimäki at 04:46 AM on 8 March 2013What doesn’t change with climate?
And after re-reading, read this:
http://skepticalscience.com/no_global_warming_from_cosmic_rays.html
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Dikran Marsupial at 04:45 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
The warming trend over the last 16 years is not statistically significant. What do you think that actually means?
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BBD at 04:43 AM on 8 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
RH - Erm, sorry about that. Not sure what happened.
Moderator Response: [RH] No problem. I'm not quite sure what happened either. -
Kevin8233 at 04:34 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Dikran Marsupial,
Let me ask the question from the opposite direction, has there been significant warming over this 16 year time frame?
Make sure the same criteria applies as to what is significant.
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Composer99 at 04:27 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Kevin:
It would help if you respond to what other people atually write rather than resorting to quote-mining. Such behaviour is extremely disingenuous and frankly reflects poorly on you.
You also need to adjust your conception on what global warming is, and how the surface temperature record reflects global warming:
As I stated before, AGW (removed the C) states that the warming originates in the atmosphere. If it slows, halts, increases, stops, starts, whatever, here, it will then and only then, continue on to the oceans, starting with the upper layer first. Regardless of whether there is an energy imbalance or not, it the temp increase stalls in the atmosphere, that will dictate a stall in global warming.
The Earth surface temperature, specifically, and atmospheric temperatures generally, are highly variable as a result of energy exhange between the atmosphere and other components of Earth system climate (mainly the cryosphere and the ocean).
One very prominent energy exchange is ENSO (El Niño/La Niña). During El Niño phases the net transfer is from the oceans to the atmosphere (increasing Earth surface temperature); the reverse is the case during La Niña years. But - and this is a very big but - ENSO does not fundamentally alter the Earth energy balance.
It is no surprise that one of the main reasons it even looks like there has been a "pause" is because there was an extraordinarily strong El Niño in 1998 and the last several years have been characterized by neutral or La Niña phases.
Bottom line: what you continue to insist is a pause is, based on the current evidence, an artifact of atmosphere-ocean energy exchange.
The way global warming can be said to be paused is if the energy imbalance at top-of-atmosphere can be shown to have disappeared and the Earth climate system as a whole can be shown to no longer be accumulating energy. Surface temperatures are unsuitable for this purpose.
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Dikran Marsupial at 03:49 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Kevin, a trend that is not significantly positive does not mean that there has been a pause; losely speaking it essentially means that the observations do not rule out the possibility of a pause. Anybody that claims that there has been a pause on the grounds of a non-significantly non-zero trend doesn't understand statistical hypothesis testing properly.
Furthermore, as has been pointed out, cherry picking the start date invalidates the hypothesis test anyway (unless you compensate for the implicit multiple hypothesis testing). -
OPatrick at 03:47 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Smith, can you honestly tell me that if you glanced at that post (and the majority of viewers of Watts' site won't do more than glance at most of the posts) you wouldn't have assumed the straight line drawn on the graph was a trend line? If it had been meant just to highlight a period it would have been more natural to draw it above or below the actual data points to avoid such confusion, or far better still to use a double headed arrow or a highlighter block, rather that a line the same width a trend line would be.
It's not a duck and Dana didn't call it a duck, he called it a fake duck.
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dhogaza at 03:39 AM on 8 March 2013What doesn’t change with climate?
"How can you say "This means that the Sun doesn’t change,"?
We know very well that solar activity is variable"
The article says the sun's output doesn't change as a result of climate change on earth, not that the sun's output doesn't ever change.
I suggest you re-read the article, perhaps more than once.
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dana1981 at 03:35 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Smith @19 - quite simply, lines on graphs in this situation usually depict linear trends. But if you want to play that game, I didn't accuse Watts of calling his yellow line a trend. I hope you're not holding me to a higher standard than you're holding Wattsy.
Kevin - choosing a starting point at an anomalously high (or low) point is the very definition of cherrypicking. If you want to argue that global warming has 'paused', make the argument by using real statistics instead of BS cherrypicking. Except you can't, because it hasn't. The only way to make the argument is with ultra-cherrypicking, as discussed in this post.
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Rob Honeycutt at 03:31 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Smith said... "Watts never claimed the yellow line was a trend."
That's a fantastically lame excuse for being lazy. In fact, lazy in a very deliberate manner.
Watts flies off the handle for the most minor errors of others but thinks he gets a pass on this? No way!
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Kevin8233 at 03:27 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
If there were really a pause in global warming, as revealed by the surface temperatures, we would need to see a negative temperature trend whose confidence intervals did not also overlap a positive number.
Wrong. That would imply that there was a decrease in the temperature, not a pause in the warming!
That is my point! Get rid of the two "escalator" stairs and compute your own trend line from 1997 to the present. The result is very close to a slope of 0, with the margin of error greater than the slope. That means it is not significant!
- NASA GISS: 0.081 ± 0.132°C/decade
- NOAA NCDC: 0.044 ± 0.121 °C/decade
- HADCRUT4: 0.046 ± 0.124 °C/decade
So what I said in 25, quoted above is inline. The margin of error is larger than the slope. At the current rate, after an additional 100 years, the temp will rise an additional 0.4 - 0.8 C. That does not seem that significant, and in fact will achieve the outcome of keeping the temp increase to less than 2 C.
As is noted in myriad other posts on this site - and in fact on this very post - the majority of the excess energy (around 90%) goes into heating the oceans. The basis of your claim is the behaviour of the Earth surface, which represents but 2-3% of the additional energy accumulation and is therefore subject to much wider variability.
As I stated before, AGW (removed the C) states that the warming originates in the atmosphere. If it slows, halts, increases, stops, starts, whatever, here, it will then and only then, continue on to the oceans, starting with the upper layer first. Regardless of whether there is an energy imbalance or not, it the temp increase stalls in the atmosphere, that will dictate a stall in global warming.
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BBD at 03:27 AM on 8 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
Andy Skuce @ 55
I thought yours an excellent question too. I have been in touch with Dr Gavin Foster, who has very kindly given permission for his response to be posted in comments here:
"That is a good question and well spotted. Our interpretation here (built on early work by us - Foster et al. 2012 attached) is that actually there must have been some northern hemisphere ice growth during the middle miocene. This is in line with a number of other indicators (e.g. ice rafted debris in the north atlantic). This does however conflict with a straightforward reading of the Zachos' benthic foram d18O curve. Its important to note though that this is not global temperature - rather its actually a mix of ice volume and temperature but the temperature of deep sea, not a global average surface. Deep water forms at high latitude so this is telling us about high latitude temperature predominantly. A recent paper by Herold et al. (2011; Paleoceanography) compiled a number of independent deep water temperature estimates for the Miocene and showed that deep water was around 6 oC warmer than today - that will account for a large chunk of the d18O change from Miocene to recent (~1 permil). We dont know why this is right now but clearly the Zachos d18O curve is not as straightforward as it first appears.The best support for our interpretation is we know from several sources (using different techniques from geochemical to stratigraphic) that there was ~70m of sea level fall during the middle miocene climate transition (the cooling that terminated the middle miocene warm period). In the absence of northern hemisphere ice this would have to be all Antarctica based ice, yet we know from ice proximal drilling that the Antarctic ice sheet was very much in existence during the Miocene (and indeed since the early Oligocene, 34 million years ago), though it may have been reduced slightly. This raises lots of more questions of course and we dont know all the answers yet but we are working on it!"
[Foster et al. (2012) abstract]Moderator Response: [RH] Fixing page formatting (I hope). ...Okay. Mostly fixed. :-) -
Doug Bostrom at 03:12 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Smith: All I am wondering is why?
Because Watts is a great artist of the Impressionist* school. There are pointilists and more lately there are linealists, with Watts being among the latter and intent on conveying an impression of a scene that is in fact not what it looks like at first glance.
*A literary style characterized by the use of details and mental associations to evoke subjective and sensory impressions rather than the re-creation of objective reality.
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Hayduke2000 at 03:10 AM on 8 March 2013What doesn’t change with climate?
This is the worst essay I've seen on this venue so far. It's upside down from start to finish.
How can you say "This means that the Sun doesn’t change,"?
We know very well that solar activity is variable, that the relationship between the Earth and the sun is variable, that variability in the sun's magnetic field influences the amount of cosmic rays that reach the Earth, which influences cloud cover.
The is a terrible post-hoc argument for human causation of climate variability.
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BBD at 03:02 AM on 8 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
Kevin
Also see Chris Colose # 64
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KR at 03:00 AM on 8 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
Kevin - if the by far largest part of the scale of temperature swings due to forcing changes is indeed long term CO2 levels (as is evident), then it is indeed dominant, and other factors are secondary.
And if that dominant factor, CO2 level, changes independently from (for example) temperature-dependent ocean solubility with temperature, the biological pump, and silicate weathering, then we should expect to see temperature changes. As observed.
If you have any evidence (paper links would be appropriate, continued semantic quibbling would not) demonstrating that CO2 is not the largest factor, then by all means present it. So far, I have seen nothing of the sort from you.
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BBD at 02:59 AM on 8 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
Kevin
Please see # 47 previous page and # 51 above and links. Too much argumentation, not enough reading.
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