Comment by techbio | Hacker News Reader

Comment by techbio | Hacker News Reader

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Scare tactics/propaganda. Whether the article is rightly or wrongly indicating something significant, I can't tell.

1. Chart shows carbon dioxide going from light red to dark red. The color scale is wildly different from the measurements (388ppm -> 404ppm -- 4%; assuredly higher, but not their drastically darkening RGB depiction (247,211,211) -> (134,3,8)

EDIT: It has been pointed out to me the percentage change is irrelevant. I'm a fairly ignorant outside observer of climate science with an interest in the presentation of this material. I saw http://xkcd.com/1732/ but many people will assume heuristic from http://xkcd.com/605/ I don't think fossil fuel is going away until prices are adjusted to the externalities. Thanks for the downvote, made me think a little harder about the importance of--(jeez, it is hard to say "politically correct" with sounding sarcastic).

2. Cherry picked a solitary data source: "At Mauna Loa Observatory, the world’s marquee site for monitoring carbon dioxide" -- Is there only one? Couldn't the article have provided a global average?

3. Animated image (with unhelpful caption) provides a little movie that looks like the northern hemisphere was on fire for the month of March 10 years ago.

This is terrible stuff. Not for passing the "symbolic threshold", but for the beautifully crafted subtexts in presentation.

HN, I welcome these threads.

Here's a dry, boring presentation of the data[0] (with a 'world average' tab as well as Mauna.) My understanding is that CO2 is close enough to well-mixed that levels are consistent at most measuring sites but Mauna one of the longest continuous same-site record and is relatively isolated [1].

The best record keeping we have is that humanity has always lived in with CO2 in the 300's [2], it will now be in the 400's until sometime quite fundamental changes (or, at current rates, it goes into the 500's in 40-50 years) [2, linear extrapolation].

[0] http://www.esrl.noaa.gov/gmd/ccgg/trends/full.html [1] https://en.wikipedia.org/wiki/Mauna_Loa_Observatory [2] http://climate.nasa.gov/vital-signs/carbon-dioxide/

Dry and boring sounds interesting. Thanks for the tip.

I had the experience of working in healthcare doing data visualization for doctors. The first version of my software I took a very "engineering" approach, a simple, no-frills just-the-facts visualization of the data, defaulting to showing as much data as possible so the well-qualified doctors could decide for themselves what was important. I found very quickly that did not work well at all. Giving a "dumb" scale of graphed data obscured the fact that your blood pressure can vary 20% in a normal conversation, while a change of 10% (F) in your temperature would be generally fatal, that streams of information from redundant sensors make it hard to discern variations in unrelated ones, that a sudden spike in heart rate is likely medically interesting, while a sudden spike in blood pressure is often an artifact of the way that information is collected. In order to effectively present information even to a highly informed audience I needed to contextualize, prune, edit and carefully present that data because by not doing the system was actually creating more confusion and misleading through data overload.

The challenge I'm sure that these climate scientists have is, they see this data not as dry, boring information, but more like health information for the planet. They would like the rate of increase of CO2 to slow and give the planet (which they live on) more time to adapt to the rapid warming which is potentially disastrous. They are trying to properly frame the fact that these are all quite bad signs so we take appropriate actions. A doctor with a patient with a fever of 107º should not present the patient with a report saying "The 2 week moving-average of your temperature is looking normal", or "your temperature is up 9% today", or "while your brain temperature is trending higher, your extremities are cooling so your average temperature is staying even". Those all might be true, but would be medical malpractice.

For comparison, when Boston got record snow and everybody froze to death in early 2015, the temperature was:

> ... the average temperature [of Boston] in February [2015] was 19.0 °F (−7.2 °C), which was 12.7 °F (7.1 °C) below the 1981–2010 normal, making it the second-coldest month of any month all-time, behind February 1934.

So the average temperature in Feb 2015 was 266K, only 2.6% below the normal value of 273K. Sheesh.

Measuring change in absolute percentage is misleading, when your chance of survival strongly depends on it being in a narrow prescribed range.

(You die if your body temperature increases by 2%.)

Nice calibration of the subject.

(You die if your body temperature increases by 2%.)

98.6 * 1.02 = 100.57, not life threatening.

98.6 F = 558.3 R; 1.02 * 558.3 R = 569.5 R; 569.5 R = 109.8 F

310.15 * 1.02 = 316.5, and you'd be dead.

There is such a thing as absolute temperature, not just different relative scales. Multiplying it makes sense.

I downvoted you because of (1.). The change in CO2 measurements should not be compared to a "baseline" of 0ppm, because that is not the baseline. It should be compared to the time-average value before, together with what the standard deviation used to be. So, looking at wikipedia, if the range since year 0 used to be ~260—280 (not sure what it was), your figure of 4% would be a wildly misleading way to present the subsequent change to 400. The baseline for CO2 is not zero.

Quickest way to get an answer on the internet, state something wrong on a forum.

Baseline CO2 apparently (from other comments) has always been in the 300+ppm range for human history, but I'm not arguing the details. If, for example, 4% of the world's people were to die from Zeka, it would make Ebola look like a sniffle.

I'm arguing the article is a too fine example of persuasive writing. I came for the comments, got a lot.

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