Did the IPCC get it right?

[billvon 3,107]

Way back in 1990 the first IPCC met and made some predictions about what would happen with the climate. And I've seen about a dozen analyses about how close they came and what factors applied.

It seems like a pretty simple question overall, so I figured I'd go back to the original sources and check for myself. First I got the original "business as usual" prediction graph from the IPCC. This assumed no massive efforts to stop AGW production, and provided a high estimate, best estimate and low estimate. I used the "best estimate" put a piece of graph paper over it and extracted the actual values (since the report just had the graph, not the values.)

Then I went to NOAA and got the global averaged temperature anomalies since 1975. NOAA does provide actual numeric values so that was easy.

Then I superimposed the graphs. There was a big offset, because NOAA uses the 20th century average as a baseline, and the first IPCC uses the average temperature from 1765 as a baseline. But those two numbers are easy to get, and they differ by .7 degrees C. So I renormalized by that.

Then I plotted the results from 1975 to 2017. (So far 2017 is the second warmest year on record, so I used that value for this year.)

Results are below. Although the IPCC's estimates have been refined since their first estimate 27 years ago, even that first estimate has been remarkably accurate.

[kallend 2,146]

billvon

Way back in 1990 the first IPCC met and made some predictions about what would happen with the climate. And I've seen about a dozen analyses about how close they came and what factors applied.

It seems like a pretty simple question overall, so I figured I'd go back to the original sources and check for myself. First I got the original "business as usual" prediction graph from the IPCC. This assumed no massive efforts to stop AGW production, and provided a high estimate, best estimate and low estimate. I used the "best estimate" put a piece of graph paper over it and extracted the actual values (since the report just had the graph, not the values.)

Then I went to NOAA and got the global averaged temperature anomalies since 1975. NOAA does provide actual numeric values so that was easy.

Then I superimposed the graphs. There was a big offset, because NOAA uses the 20th century average as a baseline, and the first IPCC uses the average temperature from 1765 as a baseline. But those two numbers are easy to get, and they differ by .7 degrees C. So I renormalized by that.

Then I plotted the results from 1975 to 2017. (So far 2017 is the second warmest year on record, so I used that value for this year.)

Results are below. Although the IPCC's estimates have been refined since their first estimate 27 years ago, even that first estimate has been remarkably accurate.

But one is a jiggly line and the other is almost straight.

Jeez!

...

The only sure way to survive a canopy collision is not to have one.

[DanG 1]

Cue rushmc saying that all the data was manipulated to fit that curve in 3...2...1...

- Dan G

[wolfriverjoe 1,523]

DanG

Cue rushmc saying that all the data was manipulated to fit that curve in 3...2...1...

No.

The "climate alarmists" went back in time and rewrote the piece to match what we are seeing.

Duh.

"There are NO situations which do not call for a French Maid outfit." Lucky McSwervy

"~ya don't GET old by being weak & stupid!" - Airtwardo

[Phil1111 1,168]

When I think of climate change I look to polar sea ice changes, global temp changes, shrinking glaciers and local weather variables.

[rushmc 23]

https://www.thegwpf.org/content/uploads/2017/09/Tsonis-17.pdf

"America will never be destroyed from the outside,
if we falter and lose our freedoms,
it will be because we destroyed ourselves."
Abraham Lincoln

[billvon 3,107]

You didn't read the article you posted, did you.

[billvon 3,107]

>Paraphrasing the conclusion: meh

Yep. I think RushMC was posting it to "refute" climate change or something like that, but the study actually assumes that warming is happening, although it does not do any analysis as to why. Specifically:

"This multi-decadal variability in global temperature trend is superimposed on a low-frequency positive trend – global warming – which accentuates warming trends and suppresses cooling trends."

" . . . it is evident from the smoothed line that on decadal timescales there are times when the global temperature trend is shifting from negative to positive and vice-versa. These ‘shifts’ are superimposed on a low-frequency signal known as ‘global warming’. Here we are not interested in the origins of the low-frequency signal. Rather we are interested in the departures from this signal on decadal timescales."

However, it does have some utility in figuring out why we see the decadal variability in the climate (which is evident in the raw NOAA data.)

[rushmc 23]

billvon

You didn't read the article you posted, did you.

I did
And I knew you would cherry pick the parts you like


http://www.telegraph.co.uk/science/2017/09/18/immediacy-threat-climate-change-exaggerated-faulty-models/

"America will never be destroyed from the outside,
if we falter and lose our freedoms,
it will be because we destroyed ourselves."
Abraham Lincoln

[rushmc 23]

Seems as though some contridictions exist here......

http://www.telegraph.co.uk/science/2017/09/18/immediacy-threat-climate-change-exaggerated-faulty-models/

"America will never be destroyed from the outside,
if we falter and lose our freedoms,
it will be because we destroyed ourselves."
Abraham Lincoln

[billvon 3,107]

>And I knew you would cherry pick the parts you like

"Cherry pick." You keep using this term. I do not think this term means what you think it means.

[DJL 235]

rushmc

Seems as though some contridictions exist here......

http://www.telegraph.co.uk/science/2017/09/18/immediacy-threat-climate-change-exaggerated-faulty-models/

By the way, good job on not linking directly from wattsup where it was published two days ago.

"I encourage all awesome dangerous behavior." - Jeffro Fincher

[billvon 3,107]

>good job on not linking directly from wattsup where it was published two days ago.

Never let it be said that people don't learn from their mistakes.

[DJL 235]

billvon

>good job on not linking directly from wattsup where it was published two days ago.

Never let it be said that people don't learn from their mistakes.

When I searched for the author "Henry Bodkin Climate Change" the wattsup link which references that article was the 6th one down.

https://wattsupwiththat.com/2017/09/19/climate-change-not-as-threatening-to-planet-as-previously-thought-new-research-suggests-2/comment-page-1/

"I encourage all awesome dangerous behavior." - Jeffro Fincher

[billvon 3,107]

I took a quick look. His first significant claim:

"According to the models used to draw up the agreement, the world ought now to be 1.3 degrees above the mid-19th-Century average, whereas the most recent observations suggest it is actually between 0.9 to 1 degree above."

First off since that's from the Guardian that's in degrees C. So what was the average temperature back in the 19th century? Good instrumental data starts around 1880. From 1880 to 1890, temps were -.27C below the 20th century mean. 2016 was .94C above the mean. So that's 1.2 degrees of increase total, 1890-2016.

So even his premise is wrong.

[billvon 3,107]

Some good news for the planet (but bad for Trump.) The conservative 10th Court of Appeals (where Gorusch came from) just ruled that coal mining companies cannot ignore the law - and must consider the effects of CO2 on the climate. From VOX:

==========================
A conservative-leaning court just issued a surprise ruling on climate change and coal mining

In a rebuke to Trump, the federal court said greenhouse gas emissions need to be considered in lease approvals.
Umair Irfan
Sep 19, 2017, 3:10pm EDT

Late last week, a federal court knocked down plans to expand coal mining in the Western US, adding to a growing body of rulings against the Trump administration’s efforts to push climate change off the agenda.

The surprising decision from the United States Court of Appeals for the 10th Circuit, which has jurisdiction in Colorado, Kansas, Utah, New Mexico, Oklahoma, and Wyoming, told the Bureau of Land Management to redo its math on greenhouse gas emissions from coal leases and sent the approval of these leases back to a lower court.

Under the National Environmental Policy Act, federal agencies have to consider how a given proposal both affects climate change and is affected by climate change.

The 10th Circuit is the highest court to rule on climate change accounting so far, and its opinion undercuts President Donald Trump’s efforts to resuscitate the dying US coal industry.

“It’s reaffirming what a lot of people already knew: Government has to take a hard look at what their environmental impacts are,” said Sam Kalen, a law professor at the University of Wyoming. “Cases like this are sending signal that regardless of what the administration wants to do, the law says you have to take a look at these issues.”

. . .

Covering a large swath of Western coal country, the 10th Circuit has a reputation for being conservative. (Trump’s Supreme Court pick Neil Gorsuch was plucked from this court.)

“Our batting average at the 10th Circuit is pretty close to zero,” said Jeremy Nichols, climate and energy program director at WildEarth Guardians.

However, the ruling fits a pattern of federal courts pushing back against agencies that are trying to gloss over their statutory climate change obligations.
==============

[coreceeo 0]

billvon

Some good news for the planet (but bad for Trump.) The conservative 10th Court of Appeals (where Gorusch came from) just ruled that coal mining companies cannot ignore the law - and must consider the effects of CO2 on the climate.

Fine then, chemical looping should suffice.

Now enough with all the drama. . .

[kallend 2,146]

Meanwhile, in Antarctica, the glaciers continue to melt:

gizmodo.com/yet-another-giant-iceberg-has-broken-free-from-antarcti-1818729430

...

The only sure way to survive a canopy collision is not to have one.