Math

[skierinvermont]

What Mallow and I are discussing about with the trend not being statistically different than zero. This is as simple and as basic of a fact as observing the sky to be blue on a sunny day.

If you want to continue to be willfully ignorant, that's your choice.

I have not ignored it. As I've said several times now there is a 10% probability that the actual trend lies outside the 95% confidence interval (of course there is also a corresponding 10% probability that the actual trend is quite a bit higher than we have observed).

You are a liar.

[Snow_Miser]

You are a liar.

Since it seems like you're not capable of having a mature and rational discussion, I think the above quote sums up how much progress we are going to make if this conversation continues.

[Snow_Miser]

Thank you, however to look at man's effect on climate you can't look at a time scale of 10,000 years. You must look at a scale of 100 or 150. According to your chart, solar radiation has been fairly stable, has it not? And the peak you see - if you look at a shorter time scale, does not correlate to the current warming that we are seeing.

Yes, climate scientists are fully aware of the sun and its variability and incorporate it into their forecast models. If the sun was behind most of the warming that we're seeing now, then how come there is such a consensus (and peer-reviewed research) that shows it is NOT behind the current warming, but increased CO2 is behind it. In fact, the models are not accurate UNTIL you incorporate increased CO2 due to man's activity.

I'm not sure if you agree that anthropogenic global warming is happening, or that it isn't. Your conclusions haven't been clear.

I agree that the anthropogenic influence should be looked at over the last 100-150 years. I was providing a chart for solar activity that has been published in the scientific literature over the last 10000 years to prove my point about solar activity now being the highest it has ever been during this timeframe.

The dramatic increase in Solar Activity correlates very nicely to a dramatic increase in temperature over the last 100 years or so. There is a significant solar component to the recent increase in surface temperatures.

Usoskin et al. 2005

There are many uncertainties associated with clouds into the models. None of the impacts from the indirect solar forcings are present in the models, the effects of cosmic rays on the global electric circuit, or the impacts of aerosols on tropospheric ozone. The climate models also poorly simulate clouds, which is another one of many shortcomings in the models (Probst et al. 2012). So using models for attribution studies may not be one of the best methods for attributing the amount of warming due to anthropogenic sources versus natural sources.

There is also not a consensus with the peer reviewed literature about how much of an impact Carbon Dioxide has on temperature. Any "consensus" study that has been published to date has been substantially criticized in the literature.

I also agree that there is a part of Global Warming that is anthropogenically induced.

My main stance is as such:

To ignore the human forcings is as nonsensical as to ignore the natural forcings. They are both important climate factors, but natural variation has been significantly downplayed by many on this forum.

[skierinvermont]

Since it seems like you're not capable of having a mature and rational discussion, I think the above quote sums up how much progress we are going to make if this conversation continues.

I agree completely. It is not possible to have a rational discussion with a liar lake yourself more interested in "winning" an argument than the truth.

You accused me of being "ignorant" and ignoring the statistical uncertainty surrounding the observed trend of +.03C/decade from 1997-present. I did not. As I said (4 or 5 times now) there is a ~10% probability that the actual trend is below zero and thus outside the 95% confidence interval (there is also a corresponding ~10% probability that the actual trend is well above the observed trend).

Your accusation is a lie. You are intentionally ignoring what I have said to make false accusations.

[Snow_Miser]

I agree completely. It is not possible to have a rational discussion with a liar lake yourself more interested in "winning" an argument than the truth.

You accused me of being "ignorant" and ignoring the statistical uncertainty surrounding the observed trend of +.03C/decade from 1997-present. I did not. As I said (4 or 5 times now) there is a ~10% probability that the actual trend is below zero and thus outside the 95% confidence interval (there is also a corresponding ~10% probability that the actual trend is well above the observed trend).

Your accusation is a lie. You are intentionally ignoring what I have said to make false accusations.

What part of the significance of an insignificant trend and zero being the same do you not understand?

[skierinvermont]

What part of the significance of an insignificant trend and zero being the same do you not understand?

A trend that is not statistically significant is NOT the same as zero.

Go back to school. This is pure stupidity.

There has not been a single person in this thread, including Mallow, that has agreed with your claim that the trend falls outside the 95% confidence interval. In fact, Mallow (and everybody else) said that claiming it falls outside the 95% confidence interval is "disingenuous, misleading, and not scientifically valid."

[Snow_Miser]

A trend that is not statistically significant is NOT the same as zero.

Go back to school. This is pure stupidity.

There has not been a single person in this thread, including Mallow, that has agreed with your claim that the trend falls outside the 95% confidence interval. In fact, Mallow (and everybody else) said that claiming it falls outside the 95% confidence interval is "disingenuous, misleading, and not scientifically valid."

I didn't say that it fell out of the 95% confidence interval. I said that a zero trend and a statistically insignificant trend are statistically indistunguishable from each other.

[skierinvermont]

I didn't say that it fell out of the 95% confidence interval. I said that a zero trend and a statistically insignificant trend are statistically indistunguishable from each other.

No, you said they are "the same." Which is blatantly false. Maybe you should read what you write. Not being able to definitively distinguish them does NOT mean they are the same.

You did claim that it is outside of the 95% confidence interval. That is what this entire argument has been about. If you would like to retract the following claim please do so clearly and we can end this discussion:

"We can say that there is a discrepancy between the forecasted and observed trends in temperatures since 1997, based off of the criteria needed to claim a discrepancy in the NOAA link above."

The NOAA link only says a discrepancy exists when the 15-yr trend is zero or below and therefore outside the 95% confidence interval.

As every poster in this thread including Mallow has explained to you, no such discrepancy exists and the trend is not outside the 95% confidence interval.

[Snow_Miser]

The NOAA link only says a discrepancy exists when the 15-yr trend is zero or below and therefore outside the 95% confidence interval.

Yes, but we can not say that the trend since 1997 on HadCruT4 is not zero, since the trend is not statistically significant.

[Mallow]

Yes, but we can not say that the trend since 1997 on HadCruT4 is not zero, since the trend is not statistically significant.

Which means you can make no conclusions one way or the other, so one cannot use it to disprove that AGW is continuing as expected.

[skierinvermont]

Which means you can make no conclusions one way or the other, so one cannot use it to disprove that AGW is continuing as expected.

^^^^This and of course this entire discussion is based off Had4 @ .03C/decade 1997-present, while GISS is .09C/decade.

All that can be said is we are probably on the low side of the confidence interval, which is not surprising given the extremely negative ENSO trend for that period and transition to much lower solar activity.