Arguments
Recent Comments
Prev 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 Next
Comments 47801 to 47850:
-
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.
-
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?
-
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.
-
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?
-
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?
-
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.
-
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
-
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>
-
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
-
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?
-
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.
-
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.
-
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.
-
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.
-
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.
-
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!
-
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.
-
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.
-
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.
-
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
-
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.
-
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.
-
Rob Honeycutt at 02:52 AM on 8 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
Kevin... I sure hope that "astrological events" is a typo on your part. I don't think you're going to find anything in any of the published literature about how the phases of scorpio or cancer will influence global temperature.
-
Composer99 at 02:52 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Kevin:
Kindly refrain from paraphrases if you are going to misrepresent what is said.
First, the data do not say what you think they are saying.
The top-of-atmosphere radiative imbalance (reported by NASA to be currently 0.8 W m-2, across the entire surface of the Earth) means that every second the Earth accumulates an additional 4.08 x108 Joules of energy over and above its current heat content. That energy has to go somewhere.
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.
In order for global warming to have genuinely halted, it must be the case that the radiative imbalance at top-of-atmosphere is no longer present. As far as I am aware no self-styled skeptic has yet to present evidence showing that this is the case.
So your characterization is entirely false.
Second, the surface temperature record is not a meaningful marker of global warming.
As described immediately above, surface and/or lower troposphere temperature records account for perhaps 2-3% of global warming.
As such, an apparent pause in the surface temperature record just doesn't reveal very much. What would be reavealing is a statistically-significant pause in ocean warming coupled with empirical findings of a long-lasting change in the TOA energy imbalance.
Third, even granting for the sake of argument that the surface temperature record is meaningful, the 1997-present trend does not mean what you think it means.
Using the Skeptical Science trend calculator, the period 1997-2013 has the the following trends (using the datasets that are compiled in the "Escalator" graphic):
- NASA GISS: 0.081 ± 0.132°C/decade
- NOAA NCDC: 0.044 ± 0.121 °C/decade
- HADCRUT4: 0.046 ± 0.124 °C/decade
The calculator indicates these are 2σ results, so (unless I am mistaken) there is a 95% probability that the actual temperature trend over this period lies within the range given by the ± values.
Because the confidence intervals overlap '0', we cannot rule out the possibility that surface temperatures have not increased in this timeframe. But - and this is a very big but with respect to your claim - we also cannot rule out the possibility that they have increased more rapidly.
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.
So, for example, the 1994-present GISTEMP trend is 0.135 ±0.106 °C/decade, which is the earliest trend in GISTEMP on the SkS trend calculator where the 2σ confidence interval does not overlap 0.
If, instead, the trend over that period was -0.135 ± 0.106 °C/decade, then we could be confident there was a pause of some kind (in the surface temperature record, anyway).
Finally, it is self-styled skeptics, not defenders of the science (who you smear as "CAGW subscribers") who are making hay over the statistically-insignificant period 1997-present, or indeed, over statistically-insignificant timeframes in the surface temperature record in general - or, in Watts' case as discussed in the OP, in the OHC record of 0-700 m depth of ocean.
-
Smith at 02:50 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
DSL@22 - Your claims to understand Watts' motivations are immaterial to my point. Watts never claimed the yellow line was a trend, Dana knew this, yet it was labeled a "Denial Fake Trend" anyway. All I am wondering is why?
-
Kevin8233 at 02:40 AM on 8 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
KR,
There are no misconceptions on my part. The title of this article claims that CO2 is the dominant control of sea level over the past 40 million years. That is quite a claim. It is interesting to note that everyone here has noted the role the Milankovich cycles has played in starting and stopping the ice ages. However,
This strongly supports the dominant role of CO2 in determining Earth’s climate on these timescales and suggests that other variables that influence long-term global climate (e.g., topography, ocean circulation) play a secondary role.
this is the quote from the abstract of the paper. Note the absense of any mention of Milankovich cycles or any other astronomical occurance. It is also interesting to note that the reference sources listed for the paper do not list any regarding astrological events. Did the author compare CO2's role to that of Milankovich cycles? Don't know.But if no comparison was made, then clearly the author can't claim that CO2 is the dominant force.
-
Smith at 02:40 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
OPatrick@20 - I have to disagree. The Watts article has the figure labeled "Sure looks like a pause to me, especially after steep rises in OHC from 1997-2003. Note the highlighted period in yellow:"
He calls it a highlighted period. A period is not a trend.
Besides, Dana1981@11 clearly states "to be fair, Watts didn't say the yellow line was a trend, just that he was 'highlighting'". So my question still stands. Why call it a "Denial Fake Trend", when Watts never claimed it was and Dana also knew it wasn't?
If it's not a duck, even though it looks like one and sounds like one, I would argue that calling it a duck anyway certainly isn't very scientific.
-
DSL at 02:25 AM on 8 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
KR, you should have bolded "but the end temperature swing is much higher with that positive feedback than it would be with just the initial forcing." That seems to be the stumbling block.
The thermostat, when left alone, brings the room to the designated equilibrium. The thermostat has several control knobs. The CO2 knob (amongst others, e.g. CH4) moves when the Solar Variation knob moves, but the CO2 knob can also be moved independently. When the Solar Variation knob moves, the CO2 knob moves at several times the rate of SV movement. Indeed, it has the greatest range of movement of any of the knobs (if we tie SV's range to its geo-historical likely range). Water vapor has a knob, but it's tied to all the other knobs, and it has a powerful spring that kicks it back to its pre-existing state almost immediately.
-
Rob Honeycutt at 02:23 AM on 8 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
BillEverett... I actually don't disagree with you. I think the difference is minor (if any difference at all). I guess I get frustrated with how "skeptics" can so easily misinterpret the meaning to be something completely wrong. Thus I want to come up with iron clad phrasing.
-
Rob Honeycutt at 02:20 AM on 8 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
jzk... It looks like you got the answer to your question @71 from BBD back at comment #37.
-
DSL at 02:10 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Kevin, a cherry-pick is a rhetorical move. It's performed in order to make the data say what the presenter wants them to say. In essence, a trend period is picked for its support or falsification of the hypothesis. The trend period is not picked for scientific/statistical reasons. Any climate energy trend of less than 30 years used to describe "climate" is a cherry-pick unless it is accompanied by methodology/caveat that accounts for short-term oscillations and forcings. Even 30 years is sketchy.
Further, anyone who uses the clause "global warming has paused/stopped/experienced a hiatus" is being imprecise, and probably for rhetorical reasons (the alternative is ignorance). Increased atmospheric CO2 will increase global energy storage, regardless of what the surface/OHC trends are doing. It will always be warmer with CO2 than without. If there are forcings/feedbacks that balance or overwhelm CO2 forcing, then the phrasing should be "the surface temp trend has recently flattened," and that should be immediately followed by analysis. It would be unphysical to claim that "global warming has stopped" when CO2 continues to rise.
Your reputation as a critical thinker is also not supported by your use of "CAGW." The acronym means nothing without definition of "C." If you'd like to provide such definition, it would help further discussion with you. However, your definition would not be universal. According to the people with whom I have engaged on this issue, the "C" includes everything from the Earth being burnt to a cinder, to 200 feet of sea level rise in the next decade, to simply "more heatwaves." People who use "CAGW" typically know that the definition is ambiguous (I've pushed at least 50 users on this point, and most agreed; the rest refused to answer). What the "C" actually does is identify you as a "skeptic." It's a little "badge of honor," a (not so) subtle sign that you're still "a member," even if you are here engaging with the enemy.
The 16-year GISS surface temp trend from 1992-2007 is .284 per decade. Did any scientist claim, in 2007, that 1) this was evidence for global warming advancing at nearly double the expected rate and/or 2) that this was an indication that the theory/models had completely failed, and that sensitivity would necessarily have to be something like 6-7C? No. Again, if you're going to discuss short-term trends, have the critical awareness to work with the short-term forcings/feedbacks/oscillations instead of immediately honing in on "global warming has stopped!"Yes, it's happening. Fire up your pyrgeometer. Go check.
-
KR at 02:09 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Also of note in this regard are Kouketsu et al 2011, showing a 0.8x1022 J/decade ocean heat content (OCH) rise in waters >3000 meters, and Levitus et al 2005, showing 14.5x1022 J rise over 1955-1998 (3.37x1022 J/decade) in OHC 0-3000 meters.
---
Kevin - Learn some statistics. The surface air temperature of 1997-present is not statistically significant, the 16 year trend is not significant, and therefore the "stall" is not statistically significant either. Claims of a "stall" are therefore meaningless, and if (as in the choice of 1997 for a starting point) the time period is specifically selected to minimize the trend, it is by definition a cherry-pick, a fallacy of incomplete evidence.
As to how long? Well, for GISTEMP 1995 is sufficient to show that the trend is significant, that the null hypothesis of no warming is invalid.
For any of the instrumental series, over any time span ending in the present:
- There is no period where warming is invalidated, against a null hypothesis of no warming.
- Against a null hypothesis of the long term warming trend, there is no period where a "no warming" hypothesis is validated. None.
- Over any period with enough data to show statistical significance, that data shows a statistically significant warming trend.
Stop cherry-picking.
-
KR at 01:45 AM on 8 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
As a note on this, and in regards to the (mis)conceptions exhibited by Kevin and others:
CO2 feedbacks to a forcing act as an amplifier of those forcings. A temperature rise reduces oceanic CO2 solubility, CO2 increases, temperature rises more. The gain is less than 1.0, so the overall effect is stable, but the end temperature swing is much higher with that positive feedback than it would be with just the initial forcing.
Note the important point - CO2 increases due to a temperature rise, increasing total radiative imbalance, temperatures rise more.
But a temperature rise and ocean solubility is not the only possible cause of a CO2 rise. For example (ahem) we have been burning fossil fuels at a tremendous rate, and have increased CO2 to levels not seen in the last million years or so. So - temperatures will rise.
---
From an electronics point of view, with CO2 as the amplifier (which might make more sense to those with engineering outlooks) - rather than increasing the input to the temperature dependent amplifier (Milankovitch forcing, with inherent time delays), we've been directly and very quickly raising the amplifier offset. With the same end result - temperatures are rising. We're turning it up to 11.
-
Kevin8233 at 01:22 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
- Satistical cherry-pick: The timeframe under consideration is too short for the trend to meet the convention of being statistically significant.
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!
What time frame do you consider long enough? If the "recent" warming period that CAGW subscribers point to as significant is roughly 30 years (1970 - 2000), then I would think that a significant "stall" of 16 years is note worthy.
- Physics cherry-pick: More importantly, the claim usually ignores the underlying physics. Global warming follows from the persistent radiative imbalance at top-of-atmosphere, and as long as this imbalance is in effect, we can be very confident that global warming is ongoing, whatever the vagaries of the surface temperature trend.
Another way to paraphrase this one is to say - regardless of the data, I know it is happening, therefore it is happening.
-
Composer99 at 01:11 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Kevin:
The point of the trend lines based on standard statistical practice in figure 4 starting at the same time as Watts' is to show that his claim (based on the eyecrometer and presumption) is false even when restricting oneself to the timeframe Watts has claimed represents a "stall".
Of course, a trend further back is plotted to show that ocean warming is in fact continuing unabated as the time frame Watts treats is much too short to be a reliable indicator of what is going on.
With regards to what constitutes cherry-picking of surface temperature (which is what the "Escalator" animated graphic is meant to lampoon), there are two ways in which claims that global warming has "stalled" or "paused" can be cherry-picks:
- Satistical cherry-pick: The timeframe under consideration is too short for the trend to meet the convention of being statistically significant.
- Physics cherry-pick: More importantly, the claim usually ignores the underlying physics. Global warming follows from the persistent radiative imbalance at top-of-atmosphere, and as long as this imbalance is in effect, we can be very confident that global warming is ongoing, whatever the vagaries of the surface temperature trend.
In any event, with regards to the specifics of your claim, pseudoskeptics have claimed in the recent past that warming has "paused" in 1997. Their claims constitute cherry-picking for the two reasons noted above.
-
Roger D at 00:27 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Kevin@ 21 - I think the trend lines for 2003-2012 are simply the trends for the two respective sets of data points; I don't think they both originate on any "data point".
To me, as a layperson, the bottomline is: Does Watts try to get at the reality of how ocean energy content is changing; if I read his blog will i be better informed? I have answer no to that question.
Why wouldn't Watts mention 700-2000m data in his post?
-
DSL at 00:11 AM on 8 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Smith, Watts knows his audience. As you imply, if someone knows what the line is about, it becomes useless and irrelevant. Why, then, would Watts include it? It's reasonable to assume that Watts communicates toward an audience he understands quite well after all these years. That yellow line was not a mistake in communication. He knows quite well that most of his audience is going to read the yellow line as a trend. Even if it's not, and they become aware of that fact, they'll assume that it's close enough. This is SOP for Watts. He's always testing the limits of his audience's gullibility (e.g. the recent Goddard silliness on Arctic ice gain).
-
Kevin8233 at 23:55 PM on 7 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Cherrypicking? Generally speaking, cherrypicking is used to show info in the best possible light, it also implies intentional misleading. To present a claim that a trend has stopped, or even alterred, you must use the data at the end of the series. Since they are making the claim that warming has stopped since X, how else should the data be presented other then showing a trend from X to the present?
If they claimed that warming had stopped in 1997 by showing data from 1997 until 2010, then your claim of cherrypicking would be accurate.
In fig 1, by presenting the data with separate trendlines for 1997 - 2003, and 2003 - present, a claim could be made for you "cherrypicking" information, as they have made the calim that warming has stopped in 1997.
In the animated fig 4, Smith(19) already pointed out the yellow line, however, in the second animation, you show two red trend lines, I guess to show the trends for Levitus and Lyman, but both trend lines originate on the Levitus data point for 2004. This is wrong and makes the trend line steeper than it is.
-
OPatrick at 23:28 PM on 7 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Smith - it looks like a trend and it quacks like a trend. Watts can call it what he likes, but only a cursory dissection is needed to see it's a herring.
-
BillEverett at 22:52 PM on 7 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
Rob Honeycutt@59, "I'm quibbling over the 'main' vs 'biggest' exactly because of the semantics issue that Kevin seems to be misunderstanding."
Okay. For me, the difference between "biggest" and "main" is rather insignificant. I used "main" in my initial comment because that was the term in Rob Painting's fifth key point and it was used in other comments preceding mine.
I prefer the more specific term "thermostat" to the general term "control knob" when using an analogy to explain the situation to other non-scientists because (1) temperature is what the knob controls and (2) it makes it easier to understand time delays between changes in CO2 and in temperature.
For those having difficulty understanding the role of greenhouse gases in our climate, I recommend the segment from 4:20 to 6:36 in a very good half-hour lecture on YouTube. -
Smith at 22:47 PM on 7 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
Dana1981@11 - Then why is the yellow line labeled "denial fake trend" in Figure 4? If you were aware it was not claimed to be a trend, what possible reason would you have to label it so?
-
Leto at 18:51 PM on 7 March 2013Cherrypicking to Deny Continued Ocean and Global Warming
As a climate layperson, I find the lameness of this latest WUWT post to be very strong evidence in favour of AGW. Even without dana's comprehensive rebuttal, it just doesn't pass the sniff test. In fact, it reeks of desparation. If there were good arguments against AGW, presumably they would be getting all the blogspace, leaving no room for this nonsense. Anyone who could draw that yellow "highlighting" line and post it in a serious, non-spoof, non-satirical blog piece is clearly in the propganda business, and not even trying to be reasonable. In fact, the whole piece, if published in another context, could be read as a tremendous spoof on denialism - and Watts doesn't even seem to realse it. The fact that his fanboys don't call him on it immediately also speaks volumes about the whole denialist subculture. They really don't seem to care what the anti-AGW argument is; anything at all will do, no matter how intellectually bankrupt.
-
jyushchyshyn at 18:37 PM on 7 March 2013China Takes a Leading Role in Solving Climate Change
"Since development of the tar sands would cripple any possible efforts by Canada to reduce their greenhouse gas emissions"
Why would the development of the tar sand cripple any possible efforts by Canada to reduce greenhouse gas emissions or even be an obsticle. Will the development of the tar sands add even one car to the roads in Canada or prevent the placement of one solar panel on the roof. Unless the U. S. were to import just as much oil from OPEC nations as it does now, why would any additional greenhouse gas emissions be produced. To stop OPEC oil imports would mean less flaring in OPEC nations.
-
BBD at 18:10 PM on 7 March 2013Carbon Dioxide the Dominant Control on Global Temperature and Sea Level Over the Last 40 Million Years
jzk
Please see 37 and links. Your questions answered.
Prev 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 Next
