Global Warming

[Orwell]

This is the part where you blow us all away with your brilliance by showing incontrovertable proof that you're right.

I'm right about there being a scientific consensus that the recent warming is largely human-caused. For instance:

Despite recent allegations to the contrary, these statements from the leadership of scientific societies and the IPCC accurately reflect the state of the art in climate science research. The Institute for Scientific Information keeps a database on published scientific articles, which my research assistants and I used to answer that question with respect to global climate change. We read 928 abstracts published in scientific journals between 1993 and 2003 and listed in the database with the keywords "global climate change." Seventy-five percent of the papers either explicitly or implicitly accepted the consensus view. The remaining 25 percent dealt with other facets of the subject, taking no position on whether current climate change is caused by human activity. None of the papers disagreed with the consensus position. There have been arguments to the contrary, but they are not to be found in scientific literature, which is where scientific debates are properly adjudicated. There, the message is clear and unambiguous.

http://www.washingtonpost.com/wp-dyn/articles/A26065-2004Dec25.html

This survey they mentioned was initially published in Science. Than there's the fact that all major scientific bodies in the United States whose members' expertise bears directly on the matter have published public statements affirming that recent warming is largely human-caused. Do you want me to list them? That sounds like scientific consensus to me.

The great majority of the experts on this subject think that global warming is largely human-caused.

 

[Bjorn]

You think so? I've read up on the subject and while I can find individual scientists that go one way or another, I can't seem to find a consensus.

Maybe not concensus, but certainly a majority including the government of the US:

In "Climate Action Report 2002", the third formal communication to the UN under the Framework Convention on Climate Change, the Bush administration says, "Greenhouse gases are accumulating in Earth's athmosphere as a result of human activities, causing global mean surface air temperature and subsurface ocean temperature to rise".

http://www.ens-newswire.com/ens/jun2002/2002-06-03-02.asp

 

[a_unique_person]

Bah. Global warming is a myth. It says so, in black and white, in the latest scientific article/novel by Crichton, State of Fear.

No reasonable person could possibly read that and think that global warming was anything other than media fueled hysteria.

Chrichton is a really poor novelist, and not a scientist. For a rebuttal of Chrichton by a scientist http://www.realclimate.org/index.php?p=74 .

For example.

Next, and slightly more troubling, we have some rather misleading and selective recollection regarding Jim Hansen's testimony to congress in 1988. "Dr. Hansen overestimated [global warming] by 300 percent" (p247). Hansen's testimony did indeed lead to a big increase in awareness of global warming as a issue, but not because he exaggerated the problem by 300%. In a paper published soon after that testimony, Hansen et al, 1988 presented three model simulations for different scenarios for the growth in trace gases and other forcings (see figure). Scenario A had exponentially increasing CO2, Scenario B had a more modest Business-as-usual assumption, and Scenario C had no further increases in CO2 after the year 2000. Both scenarios B and C assumed a large volcanic eruption in 1995. Rightly, the authors did not assume that they knew what path the carbon dioxide emissions would take, and so presented a spectrum of results. The scenario that ended up being closest to the real path of forcings growth was scenario B, with the difference that Mt. Pinatubo erupted in 1991, not 1995. The temperature change for the decade under this scenario was very close to the actual 0.11 C/decade observed (as can be seen in the figure). So given a good estimate of the forcings, the model did a reasonable job. In fact in his testimony, Hansen ONLY showed results from scenario B, and stated clearly that it was the most probable scenario. The '300 percent' error claim comes from noted climate skeptic Patrick Michaels who in testimony in congress in 1998 deleted the bottom two curves in order to give the impression that the models were unreliable.

 

[Mycroft]

I'm right about there being a scientific consensus that the recent warming is largely human-caused. For instance:

http://www.washingtonpost.com/wp-dyn/articles/A26065-2004Dec25.html

This survey they mentioned was initially published in Science. Than there's the fact that all major scientific bodies in the United States whose members' expertise bears directly on the matter have published public statements affirming that recent warming is largely human-caused. Do you want me to list them? That sounds like scientific consensus to me.

The great majority of the experts on this subject think that global warming is largely human-caused.

And yet, a disenting opinion is so easy to find:

http://www.staff.livjm.ac.uk/spsbpeis/Scienceletter.htm

On December 3rd, only days before the start of the 10th Conference of Parties of the United Nations Framework Convention on Climate Change (COP-10), Science Magazine published the results of a study by Naomi Oreskes (1): For the first time, empirical evidence was presented that appeared to show an unanimous, scientific consensus on the anthropogenic causes of recent global warming.

Oreskes claims to have analysed 928 abstracts she found listed on the ISI database using the keywords "climate change". However, a search on the ISI database using the keywords "climate change" for the years 1993 - 2003 reveals that almost 12,000 papers were published during the decade in question (2). What happened to the countless research papers that show that global temperatures were similar or even higher during the Holocene Climate Optimum and the Medieval Warm Period when atmospheric CO2 levels were much lower than today; that solar variability is a key driver of recent climate change, and that climate modeling is highly uncertain?

These objections were put to Oreskes by science writer David Appell. On 15 December 2004, she admitted that there was indeed a serious mistake in her Science essay. According to Oreskes, her study was not based on the keywords "climate change," but on "global climate change" (3).

Her use of three keywords instead of two reduced the list of peer reviewed publications by one order of magnitude (on the UK's ISI databank the keyword search "global climate change" comes up with 1247 documents). Since the results looked questionable, I decided to replicate the Oreskes study.

METHOD

I analysed all abstracts listed on the ISI databank for 1993 to 2003 using the same keywords ("global climate change") as the Oreskes study. Of the 1247 documents listed, only 1117 included abstracts (130 listed only titles, author(s)' details and keywords). The 1117 abstracts analysed were divided into the same six categories used by Oreskes (#1-6), plus two categories which I added (# 7, 8):

1. explicit endorsement of the consensus position

2. evaluation of impacts

3. mitigation proposals

4. methods

5. paleoclimate analysis

6. rejection of the consensus position.

7. natural factors of global climate change

8. unrelated to the question of recent global climate change

RESULTS

The results of my analysis contradict Oreskes' findings and essentially falsify her study:

Of all 1117 abstracts, only 13 (or 1%) explicitly endorse the 'consensus view'.

322 abstracts (or 29%) implicitly accept the 'consensus view' but mainly focus on impact assessments of envisaged global climate change.

Less than 10% of the abstracts (89) focus on "mitigation".

67 abstracts mainly focus on methodological questions.

87 abstracts deal exclusively with paleo-climatological research unrelated to recent climate change.

34 abstracts reject or doubt the view that human activities are the main drivers of the "the observed warming over the last 50 years".

44 abstracts focus on natural factors of global climate change.

470 (or 42%) abstracts include the keywords "global climate change" but do not include any direct or indirect link or reference to human activities, CO2 or greenhouse gas emissions, let alone anthropogenic forcing of recent climate change.

Which is would be just one guy with one opinion, but he seems to successfully attack the very foundation of the article that reports a scientific consensus.

 

[Orwell]

Ok, lets say that the guy is right...
Out of 1117 abstracts:

34 abstracts reject or doubt the view that human activities are the main drivers of the "the observed warming over the last 50 years.

That's way less than 1% of all abstracts (0.35%, to be exact).

335 abstracts explicitly or implicitly endorse the consensus views (30%).

I wonder on what side would the scientists who wrote the 470 abstracts that "include the keywords "global climate change" but do not include any direct or indirect link or reference to human activities, CO2 or greenhouse gas emissions, let alone anthropogenic forcing of recent climate change" would fall?

Considering the fact that the UN's Intergovernmental Panel on Climate Change (IPCC), the national academies of science of the G8 countries and Brazil, China and India, the US National Academy of Sciences, the American Meteorological Society, the American Geophysical Union, the American Association for the Advancement of Science (AAAS) have endorsed evidence of an average global temperature increase in the 20th century and stated that human activity is heavily implicated in causing this increase, I think that the percentage of scientists who reject the consensus view is probably less than 1%.

 

[Mycroft]

Ok, lets say that the guy is right...

...335 abstracts explicitly or implicitly endorse the consensus views (30%).

That's not what he said.

"322 abstracts (or 29%) implicitly accept the 'consensus view' but mainly focus on impact assessments of envisaged global climate change."

Then later he says; "It also shows that many abstracts on "evaluation of impact" and "mitigation" do not discuss which drivers are key to global climate change, instead often focusing exclusively on the possible effects of elevated CO2 levels on plant growth and vegetation. "

Meaning? You can't count the 322 abstracts that deal with impact as endorcing human driven global-warming because they concern themselves with effect, and the issue being discussed is cause. Everyone believes in global warming, the dispute is if it's purely human driven or if it's just part of the Earth's natural cycle.

 

[a_unique_person]

Oh okay. Sorry. Someone I know recently read the book and felt that it was quite convincing, well-researched and documented. I haven't read it myself.

It is useful in that it seems to list most of the popular arguments against AGW.

Once again, from realclimate.

Secondly, through the copious use of station weather data, a number of single station records with long term cooling trends are shown. In particular, the characters visit Punta Arenas (at the tip of South America), where (very pleasingly to my host institution) they have the GISTEMP station record posted on the wall which shows a long-term cooling trend (although slight warming since the 1970's). "There's your global warming" one of the good guys declares. I have to disagree. Global warming is defined by the global mean surface temperature. It does not imply that the whole globe is warming uniformly (which of course it isn't). (But that doesn't stop one character later on (p381) declaring that "..it's effect is presumably the same everywhere in the world. That's why it's called global warming"). Had the characters visited the nearby station of Santa Cruz Aeropuerto, the poster on the wall would have shown a positive trend. Would that have been proof of global warming? No. Only by amalgamating all of the records we have (after correcting for known problems, such as discussed below) can we have an idea what the regional, hemispheric or global means are doing. That is what is meant by global warming.

 

[Geckko]

I find discussions of "scientific consensus" disturbing.

I can't imagine any of the scientists I hold in high regard would take any comfort from the fact that others agree with them.

I would expect they would be more interested in those scientists who are questioning, testing and probing their work.

 

[Beerina]

There is also the issue of the consequences, and what to do about them.

The consequences are portrayed in a very chicken-little fashion, and if nothing happens, people will point to what's been done and say, see? We stopped it! This is very similar to rubbing your tummy to keep pink elephants away. You never see any? See, it worked!

And, regardless of the consequences, humanity may very well do better with a throbbing economy and the consequences than reducing the effects, but smashing the economy. There are gigatons of evidence that this may be the case in all but the most extreme of consequences.

Command-and-control of the economy doesn't care why you're doing it -- the economy busts regardless, and living standards plummet.

 

[Mark]

And yet, a disenting opinion is so easy to find:

http://www.staff.livjm.ac.uk/spsbpeis/Scienceletter.htm



Which is would be just one guy with one opinion, but he seems to successfully attack the very foundation of the article that reports a scientific consensus.

You said there was no consensus among scientists that Global Warming was human caused. Orwell showed that there is such a consesus. You then post one dissenting opinion as if that proves there is no consensus.

Consensus does not mean it is unanimous. It means a majority.

You political ideology is showing.

Btw, even the Bush Administration has admitted gw is human caused, at least in part.

 

[Mycroft]

You said there was no consensus among scientists that Global Warming was human caused. Orwell showed that there is such a consesus. You then post one dissenting opinion as if that proves there is no consensus.

Take another look at what Orwell shows us. It's an article about one scientist who did a study on the research papers of a lot of other scientists. It's not actually the opinions of a lot of scientists, it's the opinions of one scientist about a lot of scientists.

The guy that I quote trashes that study.

One scientists says; "I've looked at the table of contents of all these other studies by all these other scientists, and we have a consensus!"

The other scientist says; "No, I'm looking at the same data, and your method is deeply flawed."

So, as you see, it's really one scientists opinion versus another scientists opinion.

 

[Orwell]

That's not what he said.

"322 abstracts (or 29%) implicitly accept the 'consensus view' but mainly focus on impact assessments of envisaged global climate change."

Then later he says; "It also shows that many abstracts on "evaluation of impact" and "mitigation" do not discuss which drivers are key to global climate change, instead often focusing exclusively on the possible effects of elevated CO2 levels on plant growth and vegetation. "

Meaning? You can't count the 322 abstracts that deal with impact as endorcing human driven global-warming because they concern themselves with effect, and the issue being discussed is cause. Everyone believes in global warming, the dispute is if it's purely human driven or if it's just part of the Earth's natural cycle.

The "consensus view" is that recent warming is largely human-caused. More specifically:

1) The earth is getting warmer (0.6 +/- 0.2 degrees C in the past century; 0.1 0.17 degrees C/decade over the last 30 years)
2) People are causing this.
3) If green house gas emissions continue, the warming will continue and indeed accelerate. This will be a problem and we ought to do something about it.

The consensus that exists is that of the IPCC reports, that's what he means by the "consensus view". This IPCC report can be found here: http://www.grida.no/climate/ipcc_tar/wg1/

Therefore, if the guy you quote says that 322 abstracts implicitly accept the consensus view, then it should mean that 322 abstracts implicitly accept that recent warming is largely human-caused. If you could ask the scientists who wrote "neutral" papers that don't reject or accept the "consensus view" (probably because their papers didn't talk about human factors in global warming), there's a pretty good change that the great majority of these scientists will accept the "consensus view": you juts have to extrapolate from the already existing trend. The number of dissenting papers is tiny, and all major scientific associations have endorsed the "consensus view". It seems that the guy who wrote your article, by the way, accepts the "consensus view". Apparently, he just doesn't accept that there's a consensus.

 

[Mark]

Take another look at what Orwell shows us. It's an article about one scientist who did a study on the research papers of a lot of other scientists. It's not actually the opinions of a lot of scientists, it's the opinions of one scientist about a lot of scientists.

The guy that I quote trashes that study.

One scientists says; "I've looked at the table of contents of all these other studies by all these other scientists, and we have a consensus!"

The other scientist says; "No, I'm looking at the same data, and your method is deeply flawed."

So, as you see, it's really one scientists opinion versus another scientists opinion.

Um...OK:

In 1995, the world's climate experts in the IPCC concluded for the first time in a cautious consensus, "The balance of evidence suggests that there is a discernible human influence on the global climate."

In its 2001 assessment, the IPCC strengthened that conclusion considerably, saying, "There is new and stronger evidence that most of the warming observed over the last 50 years is attributable to human activities."

Scientists have found significant evidence that leads to this conclusion:

* The observed warming over the past 100 years is unlikely to be due to natural causes alone; it was unusual even in the context of the last 1,000 years.
* There are better techniques to detect climatic changes and attribute them to different causes.
* Simulations of the climate's response to natural causes (sun, volcanoes, etc.) over the latter half of the 20th century alone cannot explain the observed trends.
* Most simulation models that take into account greenhouse gas emissions and sulphate aerosols (which have a cooling effect) are consistent with observations over the last 50 years.

http://www.ucsusa.org/global_warming/science/global-warming-faq.html#5

Just so you know:

The Intergovernmental Panel on Climate Change (IPCC) was established by the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP) in 1988. Its main objective was to assess scientific, technical and socio-economic information relevant to the understanding of human induced climate change, potential impacts of climate change and options for mitigation and adaptation. The IPCC has completed three assessment reports, developed methodology guidelines for national greenhouse gas inventories, special reports and technical papers. For more information on the IPCC, its activities and publications, please see the IPCC homepage.
The IPCC National Greenhouse Gas Inventories Programme (IPCC-NGGIP) had been undertaken since 1991 by the IPCC WG I in close collaboration with the Organisation for Economic Co-operation and Development (OECD) and the International Energy Agency (IEA).

http://www.ipcc-nggip.iges.or.jp/

 

[Orwell]

Considering how contentious the scientific community is, I think that it is remarkable that so few papers reject the view that global warming is taking place and that this is caused by the release anthropogenic green houses gases. I mean, the rewards for finding out that this view is false are very high! There are many powerful and wealthy industries and individuals that would benefit if only the "consensus view" was proven to be wrong.

 

[fishbob]

That's assuming the conditions of last global warming events were the same.

Duh. Conditions were different last time.
There were not 7 billion people running around the planet last time.

 

[Mark]

Duh. Conditions were different last time.
There were not 7 billion people running around the planet last time.

"I don't need 6 billion of anything."---Grace Slick

(The world population was 1 billion fewer when she said that.)

 

[Grammatron]

Duh. Conditions were different last time.
There were not 7 billion people running around the planet last time.

Yes, sure, that was the only thing.

 

[Mark]

Yes, sure, that was the only thing.

If you think it wasn't by far the more crucial difference, you are kidding yourself.

 

[fishbob]

Yes, sure, that was the only thing.

I have no clue what you think your point is.

If there were only a billion or so of us, we could move to high ground, cooler climates, or uninhabited places. And most of the billion or so would probably survive.

As it is, higher ground, cooler climates, and uninhabited places are pretty much booked up. In the long run, a bunch of us probably will not survive, and the not surviving will probably be by ugly and unpleasant means.

 

[DanishDynamite]

It's simple really; some say yes and some say no.

I think it would be more correct to say that some laymen Americans say no and the rest of the world says yes.

ETA: The "rest of the world" of course also includes the well-respected scientific institutions of the US.