Free Republic
Browse · Search
General/Chat
Topics · Post Article

Skip to comments.

How The Economist got it wrong ( So the Globe really is warming?)
www.abc.net.au ^ | 12 Apr 2013 | Dana Nuccitelli and Michael E Mann

Posted on 04/14/2013 5:16:52 PM PDT by Ernest_at_the_Beach

Opinion

How The Economist got it wrong

Dana Nuccitelli and Michael E Mann

ABC Environment

12 Apr 2013

thermometer

The expected range of climate change is around 3 degrees. This is based on several lines of evidence and other factors.

Comments (23)

A recent news article suggested that climate change may not be as bad as feared. But the report was based on one flawed study and missed a lot of important points.

THE ECONOMIST recently published a lengthy article about Earth's climate sensitivity — how much the planet's surface will warm in response to the increased greenhouse effect if the amount of carbon dioxide in the atmosphere doubles relative to pre-industrial levels (something that will happen in a matter of decades if we continue with business-as-usual fossil fuel burning).

While we are pleased that The Economist brought attention to this important topic, we were disappointed by the shortcomings and inaccuracies in the piece with regard to the current state of scientific understanding.

The article focused heavily on claims that the slowed warming of Earth's surface in recent years implies a dramatically lowered estimate of climate sensitivity. The claim was primarily supported by a single as-yet unpublished article by a group in Norway, which attempts to use instrumental temperature evidence available back through the late 19th century to estimate the climate sensitivity. The authors of that article conclude that use of data to the year 2000 yields a climate sensitivity of 3.9°C, which is at the high end of the generally accepted 2 to 4.5°C range. Yet they find that by including just an additional decade of data (i.e. using observations available through 2010), the estimate falls by nearly half, to 1.9°C.

It should be a red flag that an estimate of climate sensitivity would change by a factor of two based only on the addition of a decade of data. In reality, the climate sensitivity now is not half what it was a decade ago. So where did the Norwegian study go wrong?

One likely culprit is that the role of natural climate variability, which is particularly important on timescales of a decade or less, was not properly accounted for in the analysis. One recent article published in the Journal of Geophysical Research found that internal natural variability (for example, natural oscillations in the climate like those associated with the El Niño phenomenon) can result in a sizable discrepancy (errors approaching 1°C) between the true climate sensitivity and the value of climate sensitivity derived from the instrumental record alone.

Yet another recent study published in the journal Geophysical Research Letters has argued that previously unaccounted-for effects of low-level volcanic eruptions may have offset more of the warming than scientists realised over the past decade.

And still another study published recently in Geophysical Research Letters suggests that any slowing of surface warming during the past decade may have been associated with a recent accelerated penetration of heat into the deeper oceans.

This conclusion is consistent with other recent studies finding unprecedented warming taking place in the deep oceans. According to the Intergovernmental Panel on Climate Change (IPCC), about 90 per cent of overall global warming goes into heating the oceans, while just two per cent heats the atmosphere. So the climate continues to warm, and all we may be seeing is a small change in how that warmth is being distributed between the ocean and atmosphere.


Graph of climate sensitivity
Knutti, R., Hegerl, G. C., Nature Geoscience

It is unfortunate that none of these studies and findings, each of which conflict with the dominant narrative of The Economist piece, were cited or discussed beyond a brief mention. It is further unfortunate that the piece provided so little of the larger scientific context necessary for readers to appreciate the current state of scientific knowledge about climate sensitivity. Most critically, the article didn't address why it is that the consensus estimate of climate sensitivity remains around 3°C.

The instrumental temperature record alone, it turns out, is an especially poor constraint on climate sensitivity because it is so short, and because there are multiple natural and human factors at work over the past century. For this reason, there is an extremely wide spread of estimates of climate sensitivity when only information from the instrumental record is used. That spread includes estimates that are both lower and higher than the mid-range (around 3°C) estimate (see figure above).

However, there is a wealth of other sources of information that scientists have used to try to constrain climate sensitivity (see for example this discussion at the site RealClimate). That evidence includes the paleoclimate record of the past thousand years, the specific response of the climate to volcanic eruptions, the changes in global temperature during the last ice age, the geological relationship between climate and carbon dioxide over millions of years, and more.

When the collective information from all of these independent sources of information is combined, climate scientists indeed find evidence for a climate sensitivity that is very close to the canonical 3°C estimate. That estimate still remains the scientific consensus, and current generation climate models — which tend to cluster in their climate sensitivity values around this estimate — remain our best tools for projecting future climate change and its potential impacts.

Given that it will take a significant effort to avoid doubling the amount of carbon dioxide in the atmosphere, from a policy perspective arguments about the precise climate sensitivity are somewhat irrelevant. Even at the lower end of the estimated sensitivity range, the projected impacts of climate change are likely to be devastating to human civilisation and our environment. What it will take to avoid such a scenario is what we - and The Economist - ought to be focusing on.

Dana Nuccitelli is an environmental scientist and climate blogger for Skeptical Science and The Guardian.

Michael E. Mann is Distinguished Professor of Meteorology at Penn State University. He is author of the recent book "The Hockey Stick and the Climate Wars".



TOPICS: Conspiracy; Science; Weather
KEYWORDS: climatechange; globalwarminghoax; sourcetitlenoturl

1 posted on 04/14/2013 5:16:52 PM PDT by Ernest_at_the_Beach
[ Post Reply | Private Reply | View Replies]

To: Ernest_at_the_Beach

Kinda like a pusher selling his drugs with whatever story he can.


2 posted on 04/14/2013 5:18:35 PM PDT by mountainlion (Live well for those that did not make it back.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: driftdiver

driftdiver...please pick up the white courtesy phone


3 posted on 04/14/2013 5:21:01 PM PDT by bigheadfred
[ Post Reply | Private Reply | To 1 | View Replies]

To: Ernest_at_the_Beach
One likely culprit is that the role of natural climate variability, which is particularly important on timescales of a decade or less, was...

We've come to this?
Unless the standards defining climate have changed, as well as science generally, this is a profoundly ignorant statement.
The analysis of what happens in a decade or two had always been defined as weather. Suddenly the same frauds who still today refuse to talk about the tiny number and competence of weather stations in the entire world over the previous 100 years (inadequate) and started playing with computers (apes with high tech) suddenly they knew the climate everywhere in the world for the last 100 years, and not only that, they could extrapolate for the next hundred!

After being busted for doctoring the data and destroying the original evidence so that their crime could not be verified and prosecuted, they went away. Now they're back. And everything that used to be called weather is now climate.

If the old reality didn't work out, let's redefine reality.
Suddenly what occured in the last ten years is not weather, but "climate," and they're going to try running the scam all over again.

I'm not buying it this time, either.

4 posted on 04/14/2013 6:06:52 PM PDT by publius911 (Look for the Union label, then buy something else.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: Ernest_at_the_Beach
"article focused heavily on claims that the slowed warming of Earth's surface in recent years implies a dramatically lowered estimate of climate sensitivity."

Where these clowns (Mann and Nuccitelli) get wrong is that "climate sensitivity" is simply a fudge factor that is entered into climate models to account for things that the modelers don't know anything about. A value of 1.0 represents known physics. The clowns are using a value of 3. It's this multiplication factor that turns what really is a little bit of warm weather into the dire catastrophe they want to predict.

What The Economist, and rational scientists are doing is looking at the actual data. The actual data shows that the earth hasn't warmed for over a decade. That's not even disputed anymore by the warming cultists. So, who're you gonna believe: Your lying eyes, or some effete leftists who have to exaggerate "climate sensitivity" by a factor of three in order to make catastrophic predictions that now haven't come true.

5 posted on 04/14/2013 7:18:36 PM PDT by norwaypinesavage (Galileo: In science, the authority of a thousand is not worth the humble reasoning of one individual)
[ Post Reply | Private Reply | To 1 | View Replies]

To: Ernest_at_the_Beach
It should be a red flag that an estimate of climate sensitivity would change by a factor of two based only on the addition of a decade of data. In reality, the climate sensitivity now is not half what it was a decade ago. So where did the Norwegian study go wrong?

And if you huff and puff long enough, you will eventually knock some thing down. The last decade is where the vast majority of error in your climate predictions manifested themselves. Obviously that same error was also showing in your climate sensitivity estimates.

Yes, clowns. You really were that wrong.

6 posted on 04/14/2013 8:46:53 PM PDT by justa-hairyape
[ Post Reply | Private Reply | To 1 | View Replies]

To: Ernest_at_the_Beach

...and Michael Mann. All you need to know.


7 posted on 04/14/2013 9:58:24 PM PDT by JaguarXKE (Welcome to the new America.)
[ Post Reply | Private Reply | To 1 | View Replies]

To: publius911
...and they're going to try running the scam all over again.

Because the scam is just too perfect. It's a grand slam home run for International Socialism, working on just about every level to erode and destroy the things they hate. How can they possibly be expected to give all that up, even if their premise becomes widely recognized as fraudulent? :)

8 posted on 04/15/2013 5:57:31 AM PDT by Mr. Jeeves (CTRL-GALT-DELETE)
[ Post Reply | Private Reply | To 4 | View Replies]

Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.

Free Republic
Browse · Search
General/Chat
Topics · Post Article

FreeRepublic, LLC, PO BOX 9771, FRESNO, CA 93794
FreeRepublic.com is powered by software copyright 2000-2008 John Robinson