Climate: Good Graphs, Bad Explanations

Regular readers know, I love graphs. I use them a lot. I tend to make them “scientifically,” i.e. the kind of graph you’d see in a scientific journal article. Just the fact, ma’am.

For instance, if you asked me to graph global average temperature data from NASA (using yearly averages), I’d do this (have many times):

It’s great! It’s accurate, it’s uncluttered, all the information is there.

Then I happened on this article from CNN which attempts to explain the basics of climate change. They graph NASA’s yearly average temperature data like this:

I like that! It’s not “scientifically optimal” if you ask me, but it has more visual impact for the non-scientist reader. I think the color adds tremendously to the effect. And let’s face it, scientists like color and pretty graphs too.

Personally, I’d modify it to put in the actual data (as dots) and to show some grid lines:

I think that works beautifully. I wouldn’t submit it to GRL, but I like the idea of using more graphs like this (with attractive color and visual impact) on the blog. Not always, mind you! That’s too much work.

Here’s another example: yearly average sea ice extent in the Arctic:

The next time someone points to an article from the “Global Warming Policy Foundation” about how sea ice in the Arctic is “recovering” — show ’em this graph. Hell, show this graph to Judith Curry. She might actually get it (don’t hold your breath).

The explanatory article disappointed me greatly. The first issue was “What is Climate Change?” and it was painted as a change mainly in the average temperature. It’s not just about temperature (at least there was lip service to “weather patterns”) and it sure ain’t just about the average. But at least he had a pretty graph of temperature.

The next big question being “What causes it?” I had high hopes for improvement, but this is where it really falls to pieces. The explanation is so bad, I hardly know where to begin. Go read it yourself, and feel free to notify CNN what a lousy article this is.

Sometimes I worry that I’m wasting my time explaining the basics … again. The whole issue has been in the news so much, it is finally getting talked about prominently on the national stage and at dinner tables … surely folks must have assimilated the basics by now?

Then I see that article, and I think … maybe explaining the basics is still needed, now more than ever.

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14 responses to “Climate: Good Graphs, Bad Explanations

  1. Redundancy in communication is always important, not least when it’s starting to feel superfluous, repetitive, tedious and unnecessary to the communicator.

    If people have told me that once… but hey, apparently I’m finally remembering it.

  2. “You say it again, and you say it again, and you say it again, and you say it again, and you say it again, and then again and again and again and again, and about the time that you’re absolutely sick of saying it is about the time that your target audience has heard it for the first time.”
    – Frank Luntz

  3. Correct me if I’m wrong, but here are what I think are mistakes in the article at CNN.

    “(greenhouse gases) make up roughly 0.1% of the atmosphere”
    I thought it was 0.5%.
    I have also read that water vapor varies from 0.4% to 1%
    One study finding 97% consensus
    Actually several studies
    Visible light and UV from the Sun, not heat
    The Paris Agreement — to achieve zero net carbon pollution by the end of the century.
    How about by mid century?
    Also, an explanation of the carbon cycle, and how fossil fuel emissions don’t belong in the fast carbon cycle would have been good.
    And it said nothing about extreme temperatures
    Also an explanation of how fast we are increasing CO2 compared with nature and how fast the warming is, compared with natural changes.
    Climate change can be limited and halted
    Limited yes, halted? not so much

    • salrick,
      Concerning % greenhouse gases.
      The dry atmosphere by volume contains 99.96% N2/O2/Ar by volume, none of which are GHGs. The remaining 0.04% by volume is almost all CO2. Because CO2 is heavier than the average air molecule it has a greater proportion by weight – 0.06%. Note that the CNN article does cite a reference which gives the 0.1% for “trace gases” in a dry atmosphere, although neon & helium are non-GHG trace gases – so pedantically the GHG figure used by CNN should be 0.095%.

      Concerning water vapour.
      The full atmosphere weighs 5.15 x 10^15t. Global atmospheric water is given as 13,000 cu km suggesting H2O comprises 0.25% of the atmosphere by weight. So, including H2O, for a full atmosphere, GHG content would be 0.44% by volume or 0.29% by weight.
      And note that the impact of AGW on these numbers is still quite large. Water vapour increases at 7%/ºC. So with 1ºC AGW, mankind has managed to boost the amount of atmospheric GHGs (including H2O) by about 10%, and rising. (The numbers for CO2 & H2O combined would calculate out to +11% GHG by weight, +8.7% GHG by volume.)

  4. a couple of years ago I knocked up an xyz graph with temperature on the z axis, an with a colour gradation from low to high. It was a very obvious way to depict both the warming, and the cause…

    I might try to dig it up a work next week.

  5. Speaking about graphs, any comments about the following paper, they claim to have “identified 15,295 periodic functions that perfectly fit the monthly GLST anomalies from 1880 to 2013”?
    Mao, Y.J., Tan, J.Q., Chen, B.M. and Fan, H.Y. (2019) The “Ocean Stabilization Machine” May Represent a Primary Factor Underlying the Effect of “Global Warming on Climate Change”. Atmospheric and Climate Sciences, 9, 135-145.

    [Response: It’s so bad, even the WUWT crowd doesn’t want to buy it.]

  6. I really enjoy your blog, and thanks for everything you do–been reading it for years. I would just like to make a suggestion to increase the impact of climate change communications, and it may be a controversial or unpopular one: you might want to re-think the use of graphs or charts when communicating to non-scientists on climate change. I’m a speaker and consultant on climate change issues, and I’ve learned from experience and from empirical study that graphs and data aren’t a really good way to reach most people on the issue. Many folks in the field of climate change communication are starting to eliminate graphs entirely from their presentations because they aren’t effective and they send the message that climate change is a sterile, dry problem for scientists to figure out, not a vital social and economic problem that we all must pitch in to solve. The scientific data underlying climate science is vitally important–there’s no question about that–but as climate change increasingly becomes an issue that has personal consequences, I’ve found in my work that emphasizing the human impact of climate change is far more powerful. Just my two cents. Thanks!

    • If people don’t want to think about the data, then fuck them! If they are too stupid to understand that it is the data that are telling them that climate change is a vital social and economic problem, then they are probably way too stupid to figure out what to do about it, and the next charlatan with soothing words or the next mild Summer will convert them back to skeptics again. Data is not the plural of anecdote.

      • “F*ck them!” is not an effective way to communicate the urgency of climate change. Human impact is.

        A friend of mine fled the Santa Rosa fires of 2017. His home burned down and he was literally a climate change refugee. A respiratory illness linked to the smoke exacerbated his heart condition, which killed him 6 months later.

        After he died I removed most of the graphs from my presentations on climate change and replaced them with pictures of my friend. I tell the audience they’re looking at the face of a real person who died as a result of climate change, not in Bangladesh or Kiribati, but right here in the U S. Know what the response has been? Far greater connection, far greater motivation than the reactions to a presentation where data is the central pillar.

        We want to do something about climate change, don’t we? Shouldn’t we emphasize the most effective communication strategies we can come up with?

        I’m not making this stuff up. It’s documented. If you want to connect with people on climate change, get rid of the graphs, and don’t show them that sodding polar bear on an ice floe. Show them human faces and tell human stories. Let the data speak in support, but it’s not, and never should be, the main show. I speak from experience on this.

      • Sean,
        I am sorry about your friend. But again, data is not the plural of anecdote. Both sides can wield anecdotes–they don’t even have to be rigorously true. Governor Goodhair (Rick Perry) can flash up a picture of an African villager and claim that fossil fuels are the only way to bring him/her prosperity. It isn’t true but it provides your drunk uncle with talking points for Thanksgiving.

        The data on the other hand are unequivocal–the demonstrate the reality and the threat of climate change.

        We saw in the last Presidential election how targeted advertising–anecdata–could be used to move key voting groups. That didn’t turn out well for the country. If people don’t want to be manipulated into serving the interests of the moneyed class, they had better become a helluva lot smarter. That, unfortunately, means they had better learn how to interpret data. Or if they are too stupid to understand data and vote in their own interest, they should just shut up, quit voting and hope the smart people will take their interests into account.

      • It’s got to be ‘both-and’, because it is not only a question of *knowing*, it a question of understanding deep in one’s bones that climate change is real and it is existential. Graphs and data address the need to know, and know accurately, and to have solid foundations for that knowledge. Stories and faces address the need to feel it as well as know it.

        Spokespersons and advocates probably do best to focus according to their own values; connection with their ‘passion’ will enable them to be authentic, and people respond positively to that.

        Or so the data say. ;-)

  7. What you are getting at here is important and I certainly have no final answers.

    PERSONAL stories from pre-Marduk have ALWAYS had incredibly more power to affect the psyche. Whatever it is (and I’m a PhD psych/stat) it just is there in all of us. Don’t ask me for the specs.

    Propagandists from time immemorial have known how to tap into this hard-wired part of the human genome.

    Like the Bomb forced physics to confront political reality, the “interwebs” (luv that term) is forcing all of us to confront the political–and of course–economic realities out there. Don’t ask me about the ending.