Climate scientists speak to us. What is their consensus opinion?

February 19, 2014

(FABIUS MAXIMUS) Senator Kerry kicked off the Obama administration’s campaign for policy action to fight climate change. He referred to the oft-cited 97% consensus of scientists. Since it is the basis for large and expensive policy proposals, we should know exactly what is the consensus. Here we look at the studies producing that widely cited number.

Secretary of State Kerry provides a clear example what is by now a standard play by US leaders: attempting to spark public action by exaggerating  a threat.  In this case, global warming and the resulting climate change. He gave a common but inaccurate description of the current state of climate science — exaggerating the certainty of scientists ab0ut the imminence and magnitude of the threat.

Here we compare Kerry’s words with the actual research showing the consensus. They do not match closely. The graphic at the right shows an example. Global warming is happening, but these surveys do not show agreement that “we are the cause” (rather, we are “a” cause).


However, Kerry’s misrepresentations probably will not matter. Generations of such propaganda have left the American public apathetic, our spiritual adrenal glands exhausted from over-stimulus. Only a generation or so of cold unvarnished truth can restore our ability to adequately see and assess threats. Restoring confidence in the honesty of our leaders will take longer.

“Mr. President, if that’s what you want there is only one way to get it.  That is to make a personal appearance before Congress and scare the hell out of the country.”

— Senator Arthur Vandenberg’s advice to Truman about starting the Cold War.  On 12 March 1947 Truman did so.  From Put yourself in Marshall’s place, James P. Warburg (1948); in 1941 Warburg helped develop our wartime propaganda programs.

Remarks on Climate Change by Secretary of State John Kerry at Jakarta, Indonesia 16 February 2014 — Excerpt:

So when thousands of the world’s leading scientists and five reports over a long period of time with thousands of scientists contributing to those reports – when they tell us over and over again that our climate is changing, that it is happening faster than they ever predicted, ever in recorded history, and when they tell us that we humans are the significant cause, let me tell you something: We need to listen.

When 97% of scientists agree on anything, we need to listen, and we need to respond.

  1. These scientists agree on the causes of these changes and they agree on the potential effects.
  2. They agree that the emission of greenhouse gases like carbon dioxide contributes heavily to climate change.
  3. And they agree that, if we continue to go down the same path that we are going down today, the world as we know it will change – and it will change dramatically for the worse.

There is no basis for much of this, as Kerry grossly exaggerates the extent of the consensus among climate scientists. Most of these assertions appear in the IPCC’s reports, but with widely varying confidence levels.  Stating these as certainties converts them from conclusions of scientific research into Leftist propaganda, made truth in their followers’ minds through endless repetition.

Let’s look at one claim, in a sense the foundation for the speech. What is the basis for the 97% number Kerry cites?

First, a reminder of the actual consensus of climate scientists. The surveys shown below show strong agreement with this key statement by the IPCC; none show agreement beyond it.

“It is extremely likely (95 – 100% certain) that human activities caused more than half of the observed increase in global mean surface temperature from 1951 to 2010.”
— conclusion of the IPCC’s AR5 Working Group I. See some of the research about the 1950 start date here.

Now let’s look at the research. None of them show the boundaries of consensus among climate scientists, or the fault lines of disagreement within the field (that’s not their objective). None show agreement with the claims made by Kerry.

(1) Examining the Scientific Consensus on Climate Change“, Peter T. Doran and Maggie Kendall Zimmerman, EOS, 20 January 2009 — They ask a question of little relevance to the current policy debate, followed by a uselessly vague question. The second question does not state what time period it refers to (there is no basis in the climate science literature for attributing the temperature increase before WW2 to anthropogenic factors).

Also, a sample of 79 scientists is too small to be meaningful. Thousands of scientists have written about climate change, although they classify their specialty in many ways (there were few, if any, degrees awarded in “climate science” before the 1990).

Excerpt (red emphasis added):

Q1: “When compared with pre-1800s levels, do you think that mean global temperatures have generally risen, fallen, or remained relatively constant?” 76 of 79 (96.2%) answered “risen.”

Q2: “Do you think human activity is a significant contributing factor in changing mean global temperatures?” 75 of 77 (97.4%) answered “yes.”

… In our survey, the most specialized and knowledgeable respondents (with regard to climate change) are those who listed climate science as their area of expertise and who also have published more than 50% of their recent peer-reviewed papers on the subject of climate change (79 individuals in total). Of these specialists, 96.2% (76 of 79) answered “risen” to question 1 and 97.4% (75 of 77) answered yes to question 2.

(2) Quantifying the consensus on anthropogenic global warming in the scientific literature“, John Cook et al, Environmental Research Letters, 22 April 2013 — Amateurs, readers of Cook’s website (i.e., strong believers in catastrophic anthropogenic climate change), classified papers on the following grid. This is an elaborate but amazingly poorly conceived poll. For example, the questions do not specify a time period for the warming: last decade, last century, last millennium, etc.

As with the Doran paper, the results are consistent with the IPCC’s statement, but tell us nothing more.

Read rest…


Tags: , , , , ,

You must be logged in to comment

Log in