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Comment Re:3mm is the key (Score 1) 382

http://www.skepticalscience.co...

Scroll down to figure 3... "Global mean sea level from 1870 to 2006 with one standard deviation error"

What is the first thing that you notice about the character of this plot? Is is linear? Does your statement make sense from what you know of trends and basic algerbra?

Looks pretty close to linear from where I sit. For absolute certain it's slight acceleration is grossly slower than temperature rise, so that's hopefull we aren't facing any grossly non-linear sea rise. Bonus is that in the IPCC latest report they graph instrumental to projected and it has tracked at the low end of projections.

Comment Re:It is now warmer than the '90s (Score 1) 185

The only way to declare the temperature since 1990 is warmer than any temperature in the proxy reconstructions, is to go out and take data from an ENTIRELY DIFFERENT dataset!

According to your paper, the MWP was about as warm as the '50s, and possibly as warm as the '90s. It is now much warmer than the '90s. It will continue to warm as long as we continue to release CO2. None of this is controversial.

Everything you say is based on accepting it as fair to compare instrumental temperature to proxy reconstructions.

Within the proxy reconstruction the MWP is warmer than the 1950's and the 1990's. declared this). Mann states this as a systematic problem as when calibrating his reconstruction to 1900-1950 data, the proxy reconstruction after 1950 grossly underestimated recent warming.

It is accurate to state that instrumentals since 1950 are warmer than reconstructions of the MWP. It is also accurate however to state that instrumentals since 1950 are warmer than reconstructions of temp since 1950. Holding up one without the other isn't precisely great science IMO.

Comment Re:there is no climate change ? who said that? (Score 1) 185

if quoting actual scientific papers and having the support of the climate scientist community, and having them work with you to ensure you report on and get the science correct isn't good enough for you then I don't know what to say.

but Skeptical Science is an absolutely valid source due to its exhaustive attribution, scientifically correct interpretation of the papers, and the affirmation of the climate scientists themselves.

There's a difference between valuable resource and citable references. You do not see anybody publishing research with citations to Skeptical Science. Nobody should be accepting fact X is correct because of a citation to Skeptical Science.

Using Skeptical Science to find common false arguments and corresponding references to papers refuting those false arguments is what it is good for. It's what it's stated purpose is. I'm even cool with including links to Skeptical Science interpretation of something. I am NOT cool with using Skeptical Science as an equivalent source to refute direct quotations for peer-reviewed journal articles. That's what the GP did, and it is simple not acceptable and degrades the entire debate into one of opinion and rhetoric instead of provable fact as science is supposed to be.

Comment Re:there is no climate change ? who said that? (Score 1) 185

Form my perspective the dishonesty here is entirely yours. The divergence between proxies and actual temperatures is an actual area of study within climate science. Your claims display a shocking level of ignorance and bias. It is a simple fact that we must compare the two because we don't have any temperature records from before the invention of the thermometer for reasons that should be obvious. Sure, temperature reconstructions are a poor substitute for actual measurements, but we can only use the best tools available.

Think for your own self. Of course we can't use thermometer records to look at temperatures from 1000AD. Using proxy records is one of the only methods we have to try and pull those out, and you'll note I never contested that. I contested the notion of blindly comparing results from one method to the other as though they are a single dataset. Seeing as how we can not compare directly measured temperatures back that far, we need to use proxy records. The catch is that if we want to make an honest and realistic comparison between temperature today and in 1000AD, we don't have to use two disparate datasets from separate methodologies. We can compare the proxy reconstructions of 1000AD to the proxy reconstructions of 1990AD. As I already pointed out, Michael Mann himself observes that when you do this there is a systematic underestimation of recent warming. Which you ignored when reading Mann's figure and observing:

The figure you cited clearly shows recent temperatures exceeding the peaks around 1000 AD. The summary even states:

Our results extend previous conclusions that recent Northern Hemisphere surface temperature increases are likely anomalous in a long-term context.

Now is where the Phil Jones CRU leaked comment regarding "hide the decline" comes into play. The big red line that clearly shows recent temp exceeding 1000 AD is the instrumental record. Phil Jones referenced using Mike(Mann)'s trick to "hide the decline". It was not scientific fraud in the manner of twisting or manipulating their data sets or analysis. Read Jones in defence of the usage and it is instead the same use Mann has here again. It is in the presentation of the data, by using a large bold plot of the instrumental record on the end of the graph, literally hiding beneath it the reconstructed record for recent temperatures.

So here is the point I already made laid out for I don't know how many times now. Within the dataset of temperature reconstructed from proxies, the recent temperatures were matched and exceeded in 1000AD. If you specifically ping Mann, or Jones, or Ljungqvist to the wall with exactly that question and make them answer exactly that they will agree to it. They've all published several papers repeating that finding again and again. More over, the further they refine their methods and proxy data, the stronger that result has become. Just compare Mann's early hockey stick to his most recent EIV method in his last paper.

The only context in which one can say that recent temperatures are unrivalled in the last 1k years, is if you compare two disparate datasets(proxy and instrumental). If the proxy didn't extend into the 90's you might be able to forgive that, but the fact is the proxies have started being extended into that time, and the results don't fit the narrative that some people want.

Comment Re:Mid 20th century != 1990 and beyond (Score 1) 185

I hope you realize that this:

Our two-millennia long reconstruction has a well defined peak in the period 950–1050 AD with a maximum temperature anomaly of 0.6 C.
The level of warmth during the peak of the MWP in the second half of the 10th century, equaling or slightly exceeding the mid-20th century warming, is in agreement with the results from other more recent large-scale multi-proxy temperature reconstructions

does not in any way contradict this:

Since AD 1990, though, average temperatures in the extra-tropical Northern Hemisphere exceed those of any other warm decades the last two millennia, even the peak of the Medieval Warm Period”

In fact, the second sentence is from the very paper that you seem to want to use as proof that temperatures 1000 years ago exceed those today. it is curious that the blogger you follow omitted the second sentence... possibly not a trustworthy source.

Within the proxy data reconstructions, the peak temperatures are almost exclusively during the MWP.
Most proxy data reconstructions do NOT extend past 1990.
Of the proxy data reconstructions that DO extend past 1990, Michael Mann(author) observes a systematic underestimation of recent warming.
The only way to declare the temperature since 1990 is warmer than any temperature in the proxy reconstructions, is to go out and take data from an ENTIRELY DIFFERENT dataset!
But that's OK to many people. It would seem that finding that an unprecedented change begins at the EXACT moment where you change datasets is no problem at all...

Comment Re:Last decades exceed those of any other warm dec (Score 1) 185

Skeptical science says exactly would you did, and most of what they say is sourced against another blog(RealClimate.org) which was at least started by a pair of actual scientists, but is still itself not subject to peer review either ... That's why I think the actual science must trump blogging by scientists.

You will be happy to note that the skeptical science articles in question reference Murphy 2009 Domingues et al 2008. Nuccitelli et al. (2012), Cowtan & Way (2013), Moberg et al. 2005, Mann et al. 2008, and Ljungqvist 2010 as well as NOAA and the AGU, but do not reference realclimate. Not bad if you think the actual science is important.

And wouldn't you agree that referencing those articles themselves would be a whole lot more valuable than instead referencing a blogger's interpretation?

Also of note, the author of the very paper that you give as proof that temps 1000 years ago were warmer than today says their paper shows: "Since AD 1990, though, average temperatures in the extra-tropical Northern Hemisphere exceed those of any other warm decades the last two millennia, even the peak of the Medieval Warm Period." Do you think that the analysis of your blogger is more accurate than the authors own?

I dunno who my 'blogger' is seeing as I've never referenced one?

As for the 1990 comparison, it's the same stunt Michael Mann has pulled time and again. Moreover, as I noted in my post Mann's latest paper observes that the proxy reconstructions systematically underestimate recent warming. That is to say, the 1990 temperatures that exceed even the MWP are NOT found in the same data set. Instead, they are from using an entirely different methodology of recording temperatures from thermometers and direct measurement. If you look at the work of each of the authors you cited, none of the proxy reconstructions extend out past 1990. The argument is essentially the declaration that when you change methods and datasets suddenly their is an unprecedented change.

Go look at Mann's construction I linked. He covers the last couple of decades of his graph with a big fat red line for the instrumental record to "Hide the decline", which IS exactly the reason and meaning of the much maligned phrase. Phil Jones specifically defends the usage for this purpose this way, referencing it as Mike(Mann)'s trick.

I leave it to the reader to decide if that really is particular good practice or not...

Comment Re:there is no climate change ? who said that? (Score 1) 185

Oh how I wish people would stop quoting skepticalscience as if a blog is a scientific resource.

It's kind of sad that you can make so many errors in one sentence. I referenced Skeptical Science because they have articles explaining in more detail exactly what I was explaining. I quoted one of the authors of the paper used by the parent to that post explicitly contradicting the view presented based on that's author's paper. How I wish you wouldn't ignore things that were inconvenient to you.

You only ever linked to Skeptical Science. Your italicized quote of Ljungqvist has no reference to anywhere to prove he stated, or more importantly backed it up with anything. In Ljungqvist's peer reviewed published article that your opponent linked the article declares:
Our two-millennia long reconstruction has a well defined peak in the period 950–1050 AD with a maximum temperature anomaly of 0.6 C.
The level of warmth during the peak of the MWP in the second half of the 10th century, equalling or slightly exceeding the mid-20th century warming, is in agreement with the results from other more recent large-scale multi-proxy temperature reconstructions

Sorry, I must forgive the person you responded to for thinking the science suggested that the MWP warming in 950-1050AD equalled or exceeded mid-20th century warming, seeing as it says exactly that in the scientific journal article he linked to!

For those that read this and wonder how Ljungqvist can write this in a paper yet still post the quote you gave to a blog some place, it's because he's pulling on Michael Mann's stunt of comparing apples to oranges. You use a thermometer to measure temperatures since 1900AD and you use proxy records to estimate the temperature from before and declare that the thermometer measurements are an unprecedented trend change... Or maybe, like statisticians corrected Mann on, the proxy records lack the sensitivity and precision of thermometers and comparing the two is dishonest so you save that part for your blog postings...

Skeptical science says exactly would you did, and most of what they say is sourced against another blog(RealClimate.org) which was at least started by a pair of actual scientists, but is still itself not subject to peer review either and really does not belong in your exhibit of evidences.

Isn't this just an ad hominem attack?

No just stating science is about evidence and data, not votes or opinions...

It's interesting, but I don't see the relevance here. It does not address the actual issue which is that no actual reconstructions show warming to actually have been higher in the past

Maybe because you can't be bothered to read the journal article I already linked. It's even written by Michael Mann, a very vehement AGW activist in addition to being a scientist so you should like him. I'll save you the trouble of reading the whole thing and note you can skip to Figure 3. As I pointed out, Mann chose note to plot the SH because the data wasn't as good. But even he acknowledges the best reconstruction(EIV) shows peaks around 1000AD, as did Ljungqvist's work...

Comment Re: there is no climate change ? who said that? (Score 1) 185

I did not posit anything of the kind. I merely pointed out that your impossible consequence has happened a bunch of times. I didn't say it happened because of what you described... but when your argument for something being wrong is that it would lead to x that argument only works if x is impossible or at least highly unlikely. It doesn't work when x is common.
It's as if I claimed "blah blah can't be true because if it was lots of people would die in car crashes all the time"

And if you read anything I've said, the example of our ice ages is NOTHING like the consequence of a strong positive feedback from water vapor. It would not lead to millenial ice age cycles, it would be hitting and permanently remaining in one within a century. But I'm sure you won't read that the third time if you didn't the first or second already.

Comment Re: there is no climate change ? who said that? (Score 1) 185

It has, numerous times. On one occasion the evidence suggests the polar ice caps actually met at the equator. A snowball earth. And what ends these glacial periods is probably mostly co2.

So, you are going to straight faced posit that positive feedback from water vapor was the cause of the ice ages? That's a new one.

With water vapor being as potent and short lived as it is, and with the suggestion that even a small cooling from volcanic aerosol is enough to cause it to respond, our planetary ice-age cycles look NOTHING like what should be happening. The ice ages should be abrupt and permanent, or alternatively, the boiling of the oceans should have been abrupt and permanent. As it has stood, our planet's history for hundreds of million years has been one where the average global temperature has been well below 100C and well above -100C.

Comment Re:there is no climate change ? who said that? (Score 1) 185

That's why I think the actual science must trump blogging by scientists. The final response [cusersklas...r1a0205pdf]

This link is very broken. Do you have a better link?

Ugh, sorry for that. Try here instead for the full McShane team rebuttal.

Comment Re:there is no climate change ? who said that? (Score 1) 185

Except we don't know that interaction with near the confidence you claim. The prevailing theory is that Water Vapor, which accounts for ~80% of the greenhouse effect, is short lived and there for NOT an important long term feedback mechanism.Observation however shows that after volcanic eruptions shift the global energy balance abruptly, the decreasing temperature leads to rapid feedbacks bringing the global energy balance back to 'normal'. The predominant mechanism being water vapor. So at a minimum we have witnessed repeatedly that in response to lowered temperature, water vapor acts as a negative feedback to warm things up. Luckier still for us, it doesn't continue on as a warming feedback as we approach the current global norms, it tapers off.

Large volcanic eruptions shift the global energy balance by injecting aerosols (primarily SO2) into the stratosphere where they reflect more sunlight increasing the albedo of the Earth. The reason the effect doesn't last long is that the aerosols are short lived and come back out of the atmosphere in 2 or 3 years. It has nothing to do with water vapor feedback. By cooling the atmosphere large volcanic eruptions reduce the amount of water vapor in the atmosphere.

sigh, let's start with the things I think we agree on.
Agreed:
Volcanic aerosols are a negative feedback and cool the earth.
Those aerosols are short lived.

Uncertain:
Water vapor dominates the greenhouse effect, trapping upwards of 50% of energy by it's lonesome. I am going to presume you agree with the climate scientists on this point with me, but correct me if I'm wrong.

Now for the disagree:
You claim that cooling reduces the water vapor in the atmosphere:By cooling the atmosphere large volcanic eruptions reduce the amount of water vapor in the atmosphere.

If a volcano erupts, we agree it emits aerosols into the atmosphere. We agree that these aerosols contribute to cooling. We disagree on what water vapor does. If water vapor does as you say, and contributes to cooling, how does the atmosphere recover?

  We agree in the short term the aerosols will go away. In that time though, you claim water vapor will have been contributing to more cooling. By this point the planet is considerably cooler than the few years ago the eruption occurred. That means that water vapor will be contributing to more continued cooling and a runaway cycle.

It is on you to point out why the planet hasn't been either a block of ice or burning inferno from millenia ago when the 50% contribution from water vapor went wild cooling a cooling planet or warming a warming one.

Comment Re:there is no climate change ? who said that? (Score 4, Insightful) 185

That applies to both sides.

Potentially, but not as much as you seem to think

When people point to a 15 year stabilization of temperatures as evidence in the climate change debate, the frequent response is "that's not climate, that's weather" or "that's normal variation."

The problem is those responses are actually reasonably true. In a noisy data set like yearly temperatures, we expect there to be periods of slow temperature growth and periods of fast temperature growth due to short term variability so "that's not climate, that's weather" is true, 30 year averages are generally used to minimize year-to-year variability that can drown out the long term trend. We have had a confluence of natural factors working together to slow the surface air temperature growth over that period. Perhaps more importantly it's important to look at more than just the air temperature since the atmosphere only contains a small fraction of the heat content the earth can store.

Or when they point out evidence that it was just as warm 1000 years ago as today, it will be derisively dismissed.

That's a northern hemisphere temperature reconstruction, so it only covers half the world, and one of the authors of that paper, F. C. Ljungqvist, doesn't agree with your analysis:

Since AD 1990, though, average temperatures in the extra-tropical Northern Hemisphere exceed those of any other warm decades the last two millennia, even the peak of the Medieval Warm Period”

But then there are those on the same side who will mention a 20-100 year period because it suits their argument.

Potentially, but those are periods that are long enough to cancel out year-to-year variability, though, I can't actually remember seeing anyone use a period that was longer than 30 years. Maybe it's not that the period suits the argument but that when you look at periods longer than 20 years, the evidence strongly supports one side in this debate? If that's the case, then the people who look at and accept the evidence have little choice but to end up on the same side of this debate?

Oh how I wish people would stop quoting skepticalscience as if a blog is a scientific resource.

Skeptical science says exactly would you did, and most of what they say is sourced against another blog(RealClimate.org) which was at least started by a pair of actual scientists, but is still itself not subject to peer review either and really does not belong in your exhibit of evidences. This is is what is WRONG with the whole 'debate'. Way too many folks believe themselves to be protecting and promoting the science while waving their hands at blogs and re-hashing the summaries from them. :(

One of the scientists that started RealClimate is Michael Mann, here is his latest article on historic temperatures. Mann is (in)famous for the hockey stick graph. In his latest work here he's gone a long ways to trying to improve upon his original paper and although he only graphs the NA trend(citing that the SA data is of much lower quality), it very clearly shows temperatures as measured by proxy records matched or exceeded todays temperatures on multiple occasions in the last 2k years. He tries to down play this, but the data speaks for itself. Mann even notes himself that However, in the case of the early calibration/late validation CPS reconstruction with the full screened network (Fig. 2A), we observed evidence for a systematic bias in the underestimation of recent warming. Which is to say that proxy records appear to not track the recent temperature increase so well, and might well have done the same in the past. More over, actual statisticians that have looked at Mann's methods and techniques noted the same and many other concerns around confidence in historic reconstructions. Look for yourself here. there was considerable discussion, including on on RealClimate in which you'll likely find the assessment agreeable. Mann basically declare himself the victor in the exchange on his blog.

That's why I think the actual science must trump blogging by scientists. The final response to Mann's rebuttal of the statistician's work includes the following gems. It's worth a read if you like seeing the academic equivalent of a smack down. Probably why Mann reverts to his blog there after.
They note Mann et al
make no attempt to grapple with standard errors
make absolutely no attempt to deal with uncertainties, either for a given draw of data from the simulation or across repeated draws of the simulation

That all is to summarize that the scientific literature shows that there is absolutely NOT compelling, irrefutable evidence that current temperatures are radical compared to the last 2000 years. Moreover, even Mann's own work shows it likely to have been matched in the last 1k years.

Comment Re:there is no climate change ? who said that? (Score 1) 185

This argument of yours have been completely debunked by science over and over. The main thing you're ignoring is how long things stay in the atmosphere. If your reasoning was correct we would already be boiling because water vapor leads to greenhouse, leads to more evaporation leads to more greenhouse etc. etc.

We aren't because there is a massive negative feedback system that counter-acts the effect of water vapor as a greenhouse gas almost entirely. That system is called "rain" ...
so the impact of water vapor on temperature is aggravated by CO2 - not independent there-off.

Source:
http://scholarsandrogues.com/2...

Except we don't know that interaction with near the confidence you claim. The prevailing theory is that Water Vapor, which accounts for ~80% of the greenhouse effect, is short lived and there for NOT an important long term feedback mechanism.Observation however shows that after volcanic eruptions shift the global energy balance abruptly, the decreasing temperature leads to rapid feedbacks bringing the global energy balance back to 'normal'. The predominant mechanism being water vapor. So at a minimum we have witnessed repeatedly that in response to lowered temperature, water vapor acts as a negative feedback to warm things up. Luckier still for us, it doesn't continue on as a warming feedback as we approach the current global norms, it tapers off.

Ah, but you don't care about interpreting observed scientific evidence, you'll want some links to articles.

We don't know that water vapor can truly be ignored in the long term as a feedback mechanism, it's just been the prevailing theory. In current state of the art climate models, scientists are still testing our theories on what the components of the atmosphere actually do in given scenarios. One of the steps in those model runs though is still setting parameters that approximate cloud behaviour, because we still can't afford the CPU cycles to simulate them with accuracy. Those parameters though are NOT always tuned for better cloud simulation, but INSTEAD are tuned for better TOA energy balance results. We do this because without doing that, the global energy imbalance runs off into an "unrealistic state", which is a direct quote from the IPCC. It's a better alternative to simply straight up adding/subtracting energy as we used to so it's at the moment a necessary evil. It ALSO is a clear and touchy example of where we absolutely can NOT point to our understanding of clouds and water vapor and say see, our climate models show that water vapor does X or Y. We hand tuned water vapor to autocorrect for an unknown number of errors and misunderstandings in our model. It's hardly fair or accurate to say we really understand water vapor's roll so well when our simulation of it is still so poor.

references to Cloud tuning in a coupled climate model: Impact on 20th century warming in Geophysical Research Letters and Tuning the climate of a global model by Mauritsen et al. These are THE two most thorough papers from climate modellers on the model tuning methodology and use many more words than I did to essentially say the same thing.

Comment Re:Slashdot Paradox (Score 1) 417

Slashdot is normally science-aligned. But I am surprised at how Slashdotters suddenly seem to become something akin to flat-earthers when it comes to *scientific consensus* on climate change. I don't recall this community always being like this.

A great deal of the push back from people to articles like this is that it's not a scientific journal. It's a summary of an article written by Vice, which itself references an article in Slate, which references an, at the time, unpublished discussion paper still pending peer review...

So, for the sake of those interested in the words of the actual scientists, a link to theactual discussion paper.

After bypassing all the propaganda, fud and none sense added by the journalists and going straight to the discussion paper, you STILL have a major hurdle here to people skeptical of the apocalypse now scenario.

We still have the claims from educated scientists like Michael Mann and James Hansen about the scientific consensus and how the debate is ended. The science is settled!

Now comes the twist, the IPCC that represents the global scientific 'consensus' on climate change, already made predictions for 2100 sea level rise that span from 0.2m to 0.98m. Hansen's claims of levels up to 9.0m in the recent article run against the scientific consensus on climate change, which he's championed in the past.

What do we do with the scientific consensus now? Well, hopefully we can kill the stupid idea that our universe cares about our theories and opinions and go back to evidence based reasoning. We just a name for this method to distinguish it...

Comment Re:This legislation brought to you by.. (Score 1) 446

I have a problem with the science of GMO because I don't think that humanity is nearly as smart as we think we are...FUD FUD FUD

We've been creating and eating genetically modified food since the beginning of agriculture.
Old Method: Allow untold numbers of random mutations to happen to our food. The food with random mutations and the properties we most like is the one we artificially select and keep. This is how we artificially created Canola from Rapeseed. If you want to go further back, all of our crops and livestock have undergone countless rounds of that same process for not decades, not centuries, but millennia. All along the way just ignorantly trusting that amongst the countless random mutations we've been choosing nothing is gonna go horribly awry.
New Method: Specifically and almost surgically induce only the genetic change we want to get the improved property we want.

Please, please explain how one can scientifically come to the conclusion that the safer method and the one less likely to carry unexpected and unknown side effects is NOT the method with uncounted unknown random mutations.

So far, for the most part all GMO has done for us is create new strains of food that is resistant to poisons that have ended up creating more resistant weeds. We keep hearing about all of the wonderful things that GM can do but it just doesn't get past the laboratory.

Look at Canadian Canola yields. About the year 2000 is when GMO canola started to really take hold. Average yield prior to 2000 was 24bu/ac and after 2000 has been 30.5bu/ac. Since 2005 only a twice have yields been below 30bu/ac and prior to 2000, not a single year ever reached that mark.

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