• Due to ongoing issues caused by Search, it has been temporarily disabled
  • Please excuse the mess, we're moving the furniture and restructuring the forum categories
  • You may need to edit your signatures.

    When we moved to Xenfora some of the signature options didn't come over. In the old software signatures were limited by a character limit, on Xenfora there are more options and there is a character number and number of lines limit. I've set maximum number of lines to 4 and unlimited characters.

Where did the 97% of scientists figure come from re: climate change?

Synergy

New Blood
Joined
Jun 5, 2016
Messages
3
I don't know enough about climate change to take a personal position on whether we have global warming or not. People keep telling me "97% of scientists say there is global warming that's caused by humans." Where did this 97% figure come from? I was recently told that the past two years have been exceptionally cold.
 
I found this paper that NASA references on their page about climate change.

Several studies examined published climate science papers that express a view on anthropogenic global warming. ~97% of those that can be seen to hold or express or endorse a view fall in agreement with AGW.

I believe I've also heard of direct surveys of scientists in relevant fields that yielded similar results but I'm too lazy to try to find that now.

https://iopscience.iop.org/article/10.1088/1748-9326/11/4/048002

But scientific consensus is just one argument. You can also look at the findings and models which make so many of them sure about AGW. There are so many sources out there, I won't be able to help you much better than a simple google search would.
 
Are there stats for the percentage of climate scientists among vocal climate change deniers?
 
I was recently told that the past two years have been exceptionally cold.

Whomever told you that was extremely wrong. You should always question them to provide evidence. The last 5 years, including the prior 2, have been the hottest on record.

https://www.climatecentral.org/gallery/graphics/the-10-hottest-global-years-on-record

The world continues to break far more heat records than cold records as well at a ratio of about 2 to 1.

http://www.climatesignals.org/data/record-high-temps-vs-record-low-temps
 
I suspect that whoever told you the last couple of years have been cold has been making the mistake that seems common among climate change deniers, of conflating weather with climate. Just because it's cold here in Vermont doesn't mean the earth isn't warming up.
 
The magic search word here is "ipcc". If you google for ipcc 97 like I just did, the first hit goes to a critical review of the paper that makes the claim.

A couple points.

First, that author is an economist. His expertise on the subject matter can be taken with a grain of salt.

Second, you may have missed the paper I linked from a couple years after this review which finds replication of the original claim in six different studies.

I could probably go on, but should I need to?
 
A couple points.

First, that author is an economist. His expertise on the subject matter can be taken with a grain of salt.

Second, you may have missed the paper I linked from a couple years after this review which finds replication of the original claim in six different studies.

I could probably go on, but should I need to?


You misunderstood my post. I meant it literally. Without knowing the exact answer to the question, I just googled with the IPCC magic word I did know would likely turn up relevant results and those were the results I found. I have neither read the paper nor the critical review. I was being helpful to the OP and if you want to add details, you are free to follow up.
 
Last edited:
I don't know enough about climate change to take a personal position on whether we have global warming or not.

I don't know enough about a lot of stuff to take a personal position about those topics, which is why we have experts and professionals. Do you have any basis for doubting their conclusions?

Have you looked at the evidence, for instance?

People keep telling me "97% of scientists say there is global warming that's caused by humans." Where did this 97% figure come from? I was recently told that the past two years have been exceptionally cold

For some reason I have a premonition about where you'll end up falling on this issue...

Yeah, no. Nine of the top ten hottest years on record for the last 150 years are since 2000. It's getting warmer.
 
Global Cooling period according to NASA -- 2016-2018

I have tried to post NASA documentation of global cooling, but this program will not take my post. Sorry.
 
You have to have so many posts before you can post URLs - it's a spam guard thing. Just post the web address with spaces in it, and someone here will complete it for you. Or put commas instead of the periods.
 
I have tried to post NASA documentation of global cooling, but this program will not take my post. Sorry.
I believe you are referring to the comments by Martin Mlynczak of NASA’s Langley Research Center?

“We see a cooling trend, high above Earth’s surface, near the edge of space, our atmosphere is losing heat energy. If current trends continue, it could soon set a Space Age record for cold.”

This quote was picked up out of context by the merchants of doubt and misrepresented all over the internet to mean surface temp cooling, when actually it means cooling of the outer atmosphere.

Martin Mlynczak deals with decay rates of satellites in close earth orbit, not surface warming. His comments were taken completely out of context. In fact this is part of the greenhouse effect. Less heat escapes the surface and the outer atmosphere cools and shrinks while the surface heats.

Add to that the decreased sunspot activity which is the natural cooling cycle, and we have all time recorded lows for the outer atmosphere while also still warming at the surface.

In fact we should be cooling right now. That is part of the proof of AGW actually. We should be cooling, yet temps continue to rise. The best explanation for this departure from the natural cycles is the excess CO2 buildup.
 
Last edited:
The magic search word here is "ipcc". If you google for ipcc 97 like I just did, the first hit goes to a critical review of the paper that makes the claim.

Nonsense is a better description than "critical"


https://www.theguardian.com/environ...accidentally-confirm-global-warming-consensus

basically he's arguing that papers which discuss climate related topic but don't take a position should be counted as rejecting the consensus view, which is stupid.

Also, the paper he's trying to critique is far from the first on the subject. What's actually most notable in the literature is that papers which actually try to argue against anthropogenic climate change make up less than 0.1% of the literature. Most of the contrarian papers do little more than argue for larger error bands in other work, and these papers have have generally been refuted in their own right.
 
Last edited:
I have tried to post NASA documentation of global cooling, but this program will not take my post. Sorry.

Not setting a new record for high temperatures every single year is not that same thing as "global cooling".

An oldie but obviously still relevant. BTW on this scale the "cooling" in 2018 is around 1.0 deg C, so basically off the scale.

28149d1e907d3f18.jpg
 
It was the result of a study conducted by a number of people and IIRC co-ordinated by John Cook who created the Skeptical Science website (SkS). That has since led to the Consensus Project which explains the findings and provides detail on the methodology, findings, data, etc:

Skeptical Science - The Consensus Project.
The Consensus Project.

The papers you are referring to simply confirmed previous work. Obviously the scientists themselves have known there was a strong consensus for a long time but AFAIK the first attempt to quantify the consensus was science historian Naomi Oreskes 2004 paper.

http://science.sciencemag.org/content/306/5702/1686


IIRC the 97% number first came from this paper in 2009 below which sent surveys to ~12000 earth science faculty members primarily in North America. The 3146 respondents were divided them into groups based on specialty. The most specialized group was actively publishing climate scientists. 97% of this group answered yes to the question "Do you think human activity is a significant contributing factor in changing mean global temperatures?"

https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2009EO030002
 
Last edited:
I don't know enough about climate change to take a personal position on whether we have global warming or not. People keep telling me "97% of scientists say there is global warming that's caused by humans." Where did this 97% figure come from? I was recently told that the past two years have been exceptionally cold.
From asking climate scientists (surveys) and reading what they write. The Skeptical Sceince web site already mentioned has The 97% consensus on global warming
Surveys of the peer-reviewed scientific literature and the opinions of experts consistently show a 97–98% consensus that humans are causing global warming.
This is in reply to a rather idiotic petition signed any one who claimed to be a scientist. A consensus is between experts in the field, i.e. climate scientists in this case.

This program will take your post, Synergy. If you have scientific evidence of global cooling than just write a citation. However you will not have any "Global Cooling period according to NASA -- 2016-2018" documentation because climate is not 2 years of weather! Climate is weather over periods of decades with a standard of 30 years. NASA and climate scientists know what climate is.

There is a climate myth of cooling since 1998 from cherry picking 1998 which was a very hot year on record. See What has global warming done since 1998?. Having some cooler years after a peak is not cooling climate. 2015 Was the Hottest Year on Record and people are cherry picking that date to make up a similar myth.

If you wan to see actual temperature data then Wood For Trees and its examples is a good source.
 
Back
Top Bottom