The simplest explanation for both the hiatus and the discrepancy in the models is natural variability. Much like the swings between warm and cold in day-to-day weather, chaotic climate fluctuations can knock global temperatures up or down from year to year and decade to decade. Records of past climate show some long-lasting global heatwaves and cold snaps, and climate models suggest that either of these can occur as the world warms under the influence of greenhouse gases.
By your logic that means the "trend estimation is poor" and that therefore the "period is too short to estimate a statistically significant trend."
If you want to quibble I'd say that "given the data the trend we calculated is smaller than the uncertainty". In general the uncertainty will be smaller if the period is longer.
Maybe you are having difficulty expressing yourself, but it appears as though your thinking is not being applied consistently. And I don't think you know what "statistically insignificant" means.
I think I'm being consistent - If the calculated trend is larger than the uncertainty I assume the trend is statistically significant. (Yes I know the real definition is more complicated, but this is slashdot FFS)
Your posts above serve as a good example, showing why long term trends can't disprove claims of short term trends. At best you can try to argue that the long term trend shows that the 17 year pause is not that meaningful. But in this case the pause is almost as long as the recent warming period itself, and [some] climate scientists themselves have said that a 17 year pause is meanigful (although some are now trying to change the goalposts.)
You're trying to claim that short term trends that are by your own admission not statistically significant can disprove statistically significant long term trends.
Anyways, if you still have doubts, take it up with Nature. If you are correct, they have made a big, amateur blunder. You should let them know.
I don't have to let them know. They already know. From the article you keep quoting in your attempted appeal to authority:
The simplest explanation for both the hiatus and the discrepancy in the models is natural variability.
What one can do it compare the observations with various hypotheses. Your hypothesis is, as I understand it that "warming stopped in 1997".
If that were the case we'd have a line like this, yes?
- - - - -
/ /
Temperatures after 1997 would be below an extension of the 1976-1997 trend line and the 1998-2014 trend line would start around the end of the 1976--1997 trend line.
But that isn't what we see: the (not statistically significant) 1998-2014 trend line is way above the end of the 1976-1997 trend line, and most years since 1997 have been above where the 1976-1997 trend line would have predicted them. Both of those facts falsify your hypothesis.
If fact, your original contention, that 1918-1946 is comparable to the trend from 1976-1998 allows us to check this out.
Hypothesis: warming stopped in 1946. Prediction: years after 1946 are colder than predicted by the 1918-1946 trend line
The trend "is" about 5 one-hundredths of a degree per decade. But, as you point out it is not statistically significant. What do you think "not statistically significant means? It doesn't mean "its tiny", it means "our trend estimation is poor".
The temperature trend from 1976-2014 is statistically significant however.
I'm sure they'd learn something from your technique: you measure the trend from 1997-2014 using data that starts at 1976. Insightful indeed
The problem being that you can't measure the trend from 1997-2014. The period is too short to estimate a statistically significant trend.
What one can do it compare the observations with various hypotheses. Your hypothesis is, as I understand it that "warming stopped in 1997".
If that were the case we'd have a line like this, yes?
- - - - -
/ /
Temperatures after 1997 would be below an extension of the 1976-1997 trend line and the 1998-2014 trend line would start around the end of the 1976--1997 trend line.
But that isn't what we see: the (not statistically significant) 1998-2014 trend line is way above the end of the 1976-1997 trend line, and most years since 1997 have been above where the 1976-1997 trend line would have predicted them. Both of those facts falsify your hypothesis.
What's your point? The warming trend hasn't stopped since the earth began heating after the little ice age.
I'm sorry, didn't you say:
Simple. That's [1998] about the time the warming stopped.
Which is it? Warming stopped in 1998 or warming hasn't stopped since the end of the little ice age?
The active warming period ended around 1997.
So temperatures since 1997 have been below the 1979-1997 trend?
I've grown 6 feet over 40 years. I'm arguing that I stopped growing decades ago, and that my previous growth rate, when I was actively growing, was not abnormal. You are arguing that the trend shows a growth rate of 1.5ft/decade. When my height starts to diminish as I get older, you will still be claiming a long term growth trend.
Wrong. You grew 6 feet over around 20 years, a growth rate of 3.6 inches a year.
If I made the incorrect assumption that your growth was linear over 40 years I'd calculate that your growth rate was 1.8 inches a year.
You claim that "The active warming period ended around 1997", but when we calculate the trend we find that warming 1979-1997 was 0.163 ±0.083 C/decade (2sigma) and 1979-2014 was 0. 164 ±0.037 C/decade (2sigma). I.E. warming hasn't stopped, and the warming 1979-2014 is more statistically significant (believable) than warming 1979-1997 (as one would expect).
Hypothesis: Warming stopped around end 1998.
- - - - -
/ /
Prediction: Temperatures after 1997 are on average below a naive extension of the 1979-1997 trend line.
I.E. the 1976-... trends are bigger than the 1918-1946 trend, and the 1976-2014 trend is more significant than the 1918-1946 trend, as one would expect.
Global temperatures have been increasing since the 1800's. The temperature increase where CO2 was supposedly a driver practically mirrors the temperature increase earlier in the century,
Yes, the trend from 1918-1946 is comparable to the trend from 1976-1998.
The myth is that we can wipe our ass with the biosphere continually and still live here.
If you need to feel bad to change your habits, then I hope you do. Otherwise, all else equal I would prefer that you feel good about yourself, because hurt people hurt people.
Thank you for providing supporting evidence. We're not actually doing that, but you choose to believe it anyway.
Alright. I expect to see a new window system built by you by next weekend. Let's git r dun!
Why not, it worked for Berlin/Fresco or whatever it was called.
Berlin even uses CORBA inside the display server itself, although in-process objects are accessed almost as quickly as normal objects with virtual methods.
Slashdot Mirror
, while CO2 has been at the highest levels in history,
Are you sure about that?
Why, aren't you?
Note: he said "in history". Yes, prehistoric levels have been higher.
I've read it several times.
Then maybe you need new glasses:
The simplest explanation for both the hiatus and the discrepancy in the models is natural variability. Much like the swings between warm and cold in day-to-day weather, chaotic climate fluctuations can knock global temperatures up or down from year to year and decade to decade. Records of past climate show some long-lasting global heatwaves and cold snaps, and climate models suggest that either of these can occur as the world warms under the influence of greenhouse gases.
So you haven't even read the Nature article you keep linking to.
17 years is too short? You were fine utilizing the trend between 1979-1997 when the results showed a warming trend.
17 years is too short, not because of any magic about "17 years" but because the "trend" is much smaller than the possible error:
HADCRUT4 1997-2014 Trend: 0.048 ±0.112 C/decade (2 sigma)
The trend could be anything between +0.160 and -0.064. We don't have enough information to know what the actual trend is.
By contrast for 1976-1998 the trend is:
1976-1998 HADCRUT4 Trend: 0.163 ±0.083 C/decade (2sigma)
So there is clearly a warming trend (of between +0.246 and 0.80)
And. even clearer, from 1976-2014 the trend is:
HADCRUT4 1976-2014: Trend: 0.164 ±0.037 C/decade (2 sigma).
The 1946-1980 trend is also statistically insignificant.
True:
HADCRUT4 1946-1980 Trend: -0.004 ±0.047 C/decade (2sigma)
By your logic that means the "trend estimation is poor" and that therefore the "period is too short to estimate a statistically significant trend."
If you want to quibble I'd say that "given the data the trend we calculated is smaller than the uncertainty". In general the uncertainty will be smaller if the period is longer.
Maybe you are having difficulty expressing yourself, but it appears as though your thinking is not being applied consistently. And I don't think you know what "statistically insignificant" means.
I think I'm being consistent - If the calculated trend is larger than the uncertainty I assume the trend is statistically significant. (Yes I know the real definition is more complicated, but this is slashdot FFS)
The OLS method is useful in this case to show (you guessed it) a linear trend, but can be misleading when applied to non-linear data, ie: curves. I've adjusted the dates so the curve is easier for you to spot.
So. how do you explain that the 1977-2001 trend is exactly the same as the 1977-2014 trend.
Your posts above serve as a good example, showing why long term trends can't disprove claims of short term trends. At best you can try to argue that the long term trend shows that the 17 year pause is not that meaningful. But in this case the pause is almost as long as the recent warming period itself, and [some] climate scientists themselves have said that a 17 year pause is meanigful (although some are now trying to change the goalposts.)
You're trying to claim that short term trends that are by your own admission not statistically significant can disprove statistically significant long term trends.
Anyways, if you still have doubts, take it up with Nature. If you are correct, they have made a big, amateur blunder. You should let them know.
I don't have to let them know. They already know. From the article you keep quoting in your attempted appeal to authority:
The simplest explanation for both the hiatus and the discrepancy in the models is natural variability.
What one can do it compare the observations with various hypotheses. Your hypothesis is, as I understand it that "warming stopped in 1997".
If that were the case we'd have a line like this, yes?
- - - - -
/
/
Temperatures after 1997 would be below an extension of the 1976-1997 trend line and the 1998-2014 trend line would start around the end of the 1976--1997 trend line.
But that isn't what we see: the (not statistically significant) 1998-2014 trend line is way above the end of the 1976-1997 trend line, and most years since 1997 have been above where the 1976-1997 trend line would have predicted them. Both of those facts falsify your hypothesis.
If fact, your original contention, that 1918-1946 is comparable to the trend from 1976-1998 allows us to check this out.
Hypothesis: warming stopped in 1946.
Prediction: years after 1946 are colder than predicted by the 1918-1946 trend line
Observation:
HADCRUT4 1918-1946 Trend: 0.139 ±0.057 C/decade (2sigma)
HADCRUT4 1918-1980 Trend: 0.032 ±0.020 C/decade (2sigma)
HADCRUT4 1946-1980 Trend: -0.004 ±0.047 C/decade (2sigma)
http://www.woodfortrees.org/plot/hadcrut4gl/from:1918/to:1980/plot/hadcrut4gl/from:1918/to:1946/trend/plot/hadcrut4gl/from:1946/to:1979/trend
Wow. look at that. Global warming did stop in 1946. Clearly.
Contrast: http://www.woodfortrees.org/plot/hadcrut4gl/from:1976/to:2014/plot/hadcrut4gl/from:1976/to:1997/trend/plot/hadcrut4gl/from:1998/to:2014/trend/plot/hadcrut4gl/from:1976/to:2014/trend
The HADCRUT4 temperature trend from 1997 to 2014 is about 5 one-hundredths of a degree per decade. That figure is not statistically significant.
HADCRUT4 1997-2014 Trend: 0.048 ±0.112 C/decade (2 sigma)
The trend "is" about 5 one-hundredths of a degree per decade. But, as you point out it is not statistically significant. What do you think "not statistically significant means? It doesn't mean "its tiny", it means "our trend estimation is poor".
The temperature trend from 1976-2014 is statistically significant however.
HADCRUT4 1976-2014: Trend: 0.164 ±0.037 C/decade (2 sigma).
I'm sure they'd learn something from your technique: you measure the trend from 1997-2014 using data that starts at 1976. Insightful indeed
The problem being that you can't measure the trend from 1997-2014. The period is too short to estimate a statistically significant trend.
What one can do it compare the observations with various hypotheses. Your hypothesis is, as I understand it that "warming stopped in 1997".
If that were the case we'd have a line like this, yes?
- - - - -
/
/
Temperatures after 1997 would be below an extension of the 1976-1997 trend line and the 1998-2014 trend line would start around the end of the 1976--1997 trend line.
But that isn't what we see: the (not statistically significant) 1998-2014 trend line is way above the end of the 1976-1997 trend line, and most years since 1997 have been above where the 1976-1997 trend line would have predicted them. Both of those facts falsify your hypothesis.
Sorry, typo: "Hypothesis: Warming stopped around end 1998." obviously mean "1997" (not that it changes the numbers much)
What's your point? The warming trend hasn't stopped since the earth began heating after the little ice age.
I'm sorry, didn't you say:
Simple. That's [1998] about the time the warming stopped.
Which is it? Warming stopped in 1998 or warming hasn't stopped since the end of the little ice age?
The active warming period ended around 1997.
So temperatures since 1997 have been below the 1979-1997 trend?
I've grown 6 feet over 40 years. I'm arguing that I stopped growing decades ago, and that my previous growth rate, when I was actively growing, was not abnormal. You are arguing that the trend shows a growth rate of 1.5ft/decade. When my height starts to diminish as I get older, you will still be claiming a long term growth trend.
Wrong. You grew 6 feet over around 20 years, a growth rate of 3.6 inches a year.
If I made the incorrect assumption that your growth was linear over 40 years I'd calculate that your growth rate was 1.8 inches a year.
You claim that "The active warming period ended around 1997", but when we calculate the trend we find that warming 1979-1997 was 0.163 ±0.083 C/decade (2sigma) and 1979-2014 was 0. 164 ±0.037 C/decade (2sigma). I.E. warming hasn't stopped, and the warming 1979-2014 is more statistically significant (believable) than warming 1979-1997 (as one would expect).
Hypothesis: Warming stopped around end 1998.
- - - - -
/
/
Prediction:
Temperatures after 1997 are on average below a naive extension of the 1979-1997 trend line.
Sorry, falsified.
http://www.woodfortrees.org/plot/hadcrut4gl/from:1979/plot/hadcrut4gl/from:1979/to:1997/trend/plot/hadcrut4gl/from:1979/trend
Simple. That's about the time the warming stopped.
You didn't read my comment
But why did you stop in 1998? the trend didn't
Or, to put it another way:
1918-1946 HADCRUT4 Trend: 0.139 ±0.057 C/decade (2sigma)
1976-1998 HADCRUT4 Trend: 0.163 ±0.083 C/decade (2sigma)
1976-2014 HADCRUT4 Trend: 0.164 ±0.037 C/decade (2sigma)
I.E. the 1976-... trends are bigger than the 1918-1946 trend, and the 1976-2014 trend is more significant than the 1918-1946 trend, as one would expect.
(Slashdot - fix your fucking unicode! It's 2014!)
What an Idiot. I prefer not to wait up to half an hour before I have channel information on the cable box.
Your box is broken. It shouldn't take more than a couple of seconds to boot up and be ready.
Global temperatures have been increasing since the 1800's. The temperature increase where CO2 was supposedly a driver practically mirrors the temperature increase earlier in the century,
Yes, the trend from 1918-1946 is comparable to the trend from 1976-1998.
But why did you stop in 1998? the trend didn't.
It's even stranger when you consider that whilst nuclear is both "low carbon" and "renewable"
Nuclear fission is only "renewable" if you plan to have a new supernova.
yeah, they should take that AND ITER's money and give to the NIF. Sounds like they're moving along pretty well on a teeny tiny budget...
Don't be ridiculous. NIF is a project for designing fusion weapons, not a power reactor.
Oh, and is 4 billion dollars "a teeny tiny budget" now?
We should be pursuing the legacy of Robert Brusard
If you can't even be bothered to spell his name right...
The US has just fined French bank BNP Paribas around $9 billion dollars for dealing with Sudan, Iran and Cuba.
The fine could pay for the US's ITER participation twice.
(It's not even too bad for the bank, $9 billion is about 16 months of profit).
So your saying you have experimental evidence that American drivers are idiots.
Interesting.
The myth is that we can wipe our ass with the biosphere continually and still live here.
If you need to feel bad to change your habits, then I hope you do. Otherwise, all else equal I would prefer that you feel good about yourself, because hurt people hurt people.
Thank you for providing supporting evidence. We're not actually doing that, but you choose to believe it anyway.
http://www.woodfortrees.org/plot/esrl-co2
*ALL* Species, without exception, adapt to their environment. That is how they survive.
Well no. Some species don't manage to adapt to changes in their environment.
It's survival of the fittest, not survival of all.
http://www.fresco.org/news.html
Not Found
The requested URL /news.html was not found on this server.
Sad.
Alright. I expect to see a new window system built by you by next weekend. Let's git r dun!
Why not, it worked for Berlin/Fresco or whatever it was called.
Berlin even uses CORBA inside the display server itself, although in-process objects are accessed almost as quickly as normal objects with virtual methods.
Yow buzzwords from the past!
XML is like violence.
If XML doesn't solve your problem, use more XML.
nobody saw Logon's Run here? Am I that old...?
What do you mean "saw"? I read it.
And what colour is your crystal anyway?
Not being poor is pretty good.
Having parents in managerial or engineering positions its also good.
Even parents who are teachers helps.
At least [EU] HAS a parliament, unlike the WTO, NATO
EU has a powerless parliament, who cannot propose a directive, who cannot have the last word against the EU council (except to reject a directive),
So they cannot have the last word, except that they have the last word?
and who does not decide the budget.
Except that they can reject it.
The power to destroy a thing is the absolute control over it.
-- Paul-Muad'Dib
The non elected EU commission that is only real power in the EU besides the individual ministers of each country that deal with european affairs.
The commission is the cabinet. I cannot think of any system where the cabinet is elected.
Since the electing circles in the EU and most of Europe don't work as in the UK/US, you'd have to explain everyone how a senate works
Why would someone from the UK know how a senate works? The UK doesn't have a senate.