• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar
  • Skip to footer

RealClimate

Climate science from climate scientists...

  • Home
  • Start here
  • Contributors
  • Archives
You are here: Home / 2004 / Archives for December 2004

Archives for December 2004

Imprecision of the Phrase “Global Warming”

31 Dec 2004 by Gavin

Guest Contribution by Michael Tobis, University of Chicago

Consider the possibility that the expression “global warming” has become a problematic one, and that it might be best to avoid it.

A big part of the public confusion about climate change comes from sloppy language. The naysayers prey on this confusion, very much as their peers prey on the phrase “evolutionary theory” to suggest that “evolution, well, it’s just a theory”.

[Read more…] about Imprecision of the Phrase “Global Warming”

Filed Under: Climate Science

Will-full ignorance

26 Dec 2004 by eric

It is not worthwhile for RealClimate to post a response to each misinformed newspaper commentary on climate change that we come across. However, George Will’s recent article in the Washington post (in which he praises Michael Crichton’s State of Fear) perhaps deserves special attention because Will is so widely read and respected. We find it disappointing that Will appears not to have bothered looking up the most basic facts before writing his article. See also our earlier post on the George Will article.

We have already posted detailed responses to State of Fear. Here, we respond briefly to the points Will tries to make. The italics are direct quotes from his article.

[Read more…] about Will-full ignorance

Filed Under: Climate Science

George Will-misled and misleading

24 Dec 2004 by Ray Bradley

In a Washington Post Opinion article on December 22, 2004, commentator George Will applauds Michael Crichton’s new book, State of Fear. We have already pointed out some of the more egregious scientific errors in Crichton’s novel (see Michael Crichton’s State of Confusion ). Mr. Will compounds those errors and fails his own standards by making statements that are truly “innocent of information but overflowing with certitudes”.

[Read more…] about George Will-misled and misleading

Filed Under: Climate Science

A Welcoming Nature

22 Dec 2004 by Gavin

Getting a serious paper into Nature or Science is deservedly hard. Getting a mention for your climate blog is apparently a little easier!

We are of course collectively very pleased that Nature has welcomed the RealClimate.org effort so forthrightly. We only hope that we will be able to match up to their expectations. As with anything new, done by inexperienced first-timers who really should be concentrating on their actual jobs, there are bound to be teething problems. One, alluded to in the editorial and accompanying news story, is who gets to decide what’s posted, and getting the balance right between inclusiveness and clarity.

[Read more…] about A Welcoming Nature

Filed Under: Climate Science, In the News

How do we know that recent CO2 increases are due to human activities?

22 Dec 2004 by eric

Translations: (Svenska) (Español) (Français)

Note:This is an update to an earlier post, which many found to be too technical. The original, and a series of comments on it, can be found here. See also a more recent post here for an even less technical discussion.

Over the last 150 years, carbon dioxide (CO2) concentrations have risen from 280 to nearly 380 parts per million (ppm). The fact that this is due virtually entirely to human activities is so well established that one rarely sees it questioned. Yet it is quite reasonable to ask how we know this.

[Read more…] about How do we know that recent CO2 increases are due to human activities?

Filed Under: Climate Science, FAQ, Greenhouse gases, Paleoclimate

Just what is this Consensus anyway?

22 Dec 2004 by group

Translations: (Français)

We’ve used the term “consensus” here a bit recently (see our earlier post on the subject), without ever really defining what we mean by it. In normal practice, there is no great need to define it – no science depends on it. But it’s useful to record the core that most scientists agree on, for public presentation. The consensus that exists is that of the IPCC reports, in particular the working group I report (there are three WG’s. By “IPCC”, people tend to mean WG I). Fortunately that report is available online for all to read at http://www.grida.no/climate/ipcc_tar/wg1/. It’s a good idea to realise that though the IPCC report contains the consensus, it didn’t form it. The IPCC process was supposed to be – and is – a summary of the science (as available at the time). Because they did their job well, it really is a good review/summary/synthesis.

[Read more…] about Just what is this Consensus anyway?

Filed Under: Climate Science, FAQ

Aerosol

21 Dec 2004 by group

Translations: (Français)

A collection of airborne solid or liquid particles, with a typical size between 0.01 and 10 µm and residing in the atmosphere for at least several hours. Aerosols may be of either natural or anthropogenic origin. Aerosols may influence climate in two ways: directly through scattering and absorbing radiation, and indirectly through acting as condensation nuclei for cloud formation or modifying the optical properties and lifetime of clouds (from the always useful IPCC glossary).

See-also: wiki:Aerosol.

Filed Under: Glossary

Fox News gets it wrong

18 Dec 2004 by Ray Bradley

In a December 17th Fox News story (See full report here) Steven Milloy comments on a lecture by Lonnie Thompson at the Annual meeting of the American Geophysical Union in San Francisco. He uses a common ploy of truncating what Thompson said, to ensure that a quotation fits with his message. According to Milloy, Thompson said, “Any prudent person would agree that we don’t yet understand the complexities with the climate system.” But what he actually said was “Any prudent person would agree that we don’t yet understand the complexities with the climate system and, since we don’t, we should be extremely cautious in how much we ‘tweak’ the system.” (see full press release here). Such manipulations are designed so that Milloy can’t be accused of misquoting, but clearly, he completely contorts Thompson’s point. Milloy also misunderstands the science.

[Read more…] about Fox News gets it wrong

Filed Under: Climate Science

How do we know that recent CO2 increases are due to human activities?

16 Dec 2004 by eric

An updated version of this post is now available.

The fact that CO2 increases in the past 150 years are due virtually entirely to human activities is so well established that one rarely sees it questioned. Yet is is quite reasonable to ask how we know this.

There are actually multiple, largely independent lines of reasoning, discussed in some detail in the IPCC TAR report, Chapter 3. One of the best illustrations of this point, however, is not given in IPCC. Indeed, it seems not all that well appreciated in the scientific community, and is worth making more widely known.

Carbon is composed of three different isotopes 14C, 13C and 12C of which 12C is the most common and 14C (used for dating purposes) is only about 1 in 1 trillion atoms. 13C is about 1% of the total.

Over the last few decades, isotope geochemists have worked together with tree rings experts to construct a time series of atmospheric 14C variations over the last 10,000 years. This work is motivated by a variety of questions, most having to do with increasing the accuracy of the radiocarbon dating method. A byproduct of this work is that we also have a very nice record of atmospheric 13C variations through time, and what we find is that at no time in the last 10,000 years are the 13C/12C ratios in the atmosphere as low as they are today. Furthermore, the 13C/12C ratios begin to decline dramatically just as the CO2 starts to increase — around 1850 AD. This is no surprise because fossil fuels have lower 13C/12C ratios than the atmosphere.

The total change is about 0.15%, which sounds very small but is actually very large relative to natural variability. Although it has proved quite challenging to do the analyses, there are a limited number of measurements of the 13C/12C ratio in ice cores. The results show that the full glacial-to-interglacial change in 13C/12C of the atmosphere — which took many thousand years — was about 0.03% 00 or about 5 times less than that observed in the last 150 years. The ice core data also agree quite well with the tree ring data where these data sets overlap.

I will put a couple of plots up when I get a chance. For those who are interested, some relevant references are: Stuiver, M., Burk, R. L. and Quay, P. D. 1984. 13C/12C ratios and the transfer of biospheric carbon to the atmosphere. J. Geophys. Res. 89, 1731�1748. for tree rings, and
Francey, R.J., Allison, C.E., Etheridge, D.M., Trudinger, C.M., Enting, I.G., Leuenberger, M., Langenfelds, R.L., Michel, E., Steele, L.P., 1999. A 1000-year high precision record of d 13Cin atmospheric CO. Tellus 51B, 170�193.

Filed Under: Attic

Statistical analysis of consensus

16 Dec 2004 by eric

Translations: (Français)

Is there really “consensus” in the scientific community on the reality of anthropogenic climate change? As N. Oreskes points out in a recent article in Science, that is itself a question that can be addressed scientificially. Oreskes took a sampling of 928 articles on climate change, selected objectively (using the key phrase “global climate change”) from the published peer-reviewed scientific literature. Oreskes concluded that of those articles (about 75% of them) that deal with the question at all, 100% (all of them) support the consensus view that a significant fraction of recent climate change is due to human activities. Of course, there are undoubtedly some articles that have been published in the peer-reviewed literature that disagree with this position and that Oreskes’s survey missed, but the fact that her sample didn’t [Read more…] about Statistical analysis of consensus

Filed Under: Climate Science

  • Go to page 1
  • Go to page 2
  • Go to page 3
  • Interim pages omitted …
  • Go to page 5
  • Go to Next Page »

Primary Sidebar

Email Notification

get new posts sent to you automatically (free)
Loading

Recent Posts

  • Some new CMIP6 MSU comparisons
  • How not to science
  • Unforced variations: March 2023
  • The established ground and new ideas
  • 2022 updates to model-observation comparisons
  • Unforced variations: Feb 2023

Our Books

Book covers
This list of books since 2005 (in reverse chronological order) that we have been involved in, accompanied by the publisher’s official description, and some comments of independent reviewers of the work.
All Books >>

Recent Comments

  • Barton Paul Levenson on Unforced variations: March 2023
  • Piotr on Unforced variations: March 2023
  • Barton Paul Levenson on Unforced variations: March 2023
  • Carbomontanus on Unforced variations: March 2023
  • JCM on Unforced variations: March 2023
  • Victor on Unforced variations: March 2023
  • Carbomontanus on Some new CMIP6 MSU comparisons
  • Ron R. on Unforced variations: March 2023
  • Ron R. on Unforced variations: March 2023
  • Carbomontanus on Unforced variations: March 2023
  • Mike on 2022 updates to model-observation comparisons
  • Mike on 2022 updates to model-observation comparisons

Footer

ABOUT

  • About
  • Translations
  • Privacy Policy
  • Contact Page
  • Login

DATA

  • Data Sources
  • Climate model projections compared to observations

INDEX

  • Acronym index
  • Index

Realclimate Stats

1,296 posts

8 pages

230,107 comments

Copyright © 2023 · RealClimate is a commentary site on climate science by working climate scientists for the interested public and journalists.