Why comparing global warming to the Hiroshima Atomic Bomb is ridiculous
Some days, you just have to laugh. That’s what we’ll have to do today after reading the latest ridiculous scare story from cartoonist turned pseudo-psychologist now elevated to ‘climate scientist’ John Cook from the antithetically named ‘Skeptical Science’ website.
He’d like people to think the effect of global warming is as powerful as the effect of an atomic bomb, but as we’ll see, it is another one of those scare by scale stories where you grab some iconic image from the public consciousness and use it to make your issue seem bigger than it really is. For example, in 2010 normally calving glacier ice was compared to Manhattan Island to give it scale: Oh no! Greenland glacier calves island 4 times the size of Manhattan
Now, the same trick is being used by John Cook to try to scare people, because what could be more scary than getting vaporized by an Atomic Bomb? It just goes to show the depths of desperation used to try to sell the public on a problem that isn’t getting much traction.
From the article Climate change like atom bomb: scientists.
Humans are emitting more carbon dioxide into the atmosphere than any other time in history, says John Cook, Climate Communication Fellow from the Global Change Institute at the University of Queensland.
“All these heat-trapping greenhouse gases in our atmosphere mean … our planet has been building up heat at the rate of about four Hiroshima bombs every second – consider that going continuously for several decades.”
Whoa, four Hiroshima bombs every second. How scary is that? Well not only is it not an original idea by Cook, compared to the amount of energy received by the Earth from the biggest fusion bomb in our solar system, our sun, it hardly registers a blip.
You see, we’ve dealt with this nonsense before, back in May 2012 when NASA’s Dr. Hansen made the same comparison, which Cook didn’t attribute to him. Hansen said then in an article in the Vancouver Observer:
In a must-see TED talk, NASA climate scientist James Hansen say the current increase in global warming is:
“…equivalent to exploding 400,000 Hiroshima atomic bombs per day 365 days per year. That’s how much extra energy Earth is gaining each day.”
That’s 278 atomic bombs worth of energy every minute – more than four per second — non-stop. To be clear, that is just the extra energy being gained each day on top of the energy heating our planet by 0.8 degree C. It is the rate at which we are increasing global warming.
Let’s do the numbers. First, let’s convert the extra heat into an iconic image people can understand that isn’t quite as scary: the incandescent light bulb (not the twisty kind). Willis Eschenbach calculated:
1 ton of TNT = 4.184e+9 joules (J) source
Hiroshima bomb = 15 kilotons of TNT = 6.28e+13 joules (ibid)
Hansen says increase in forcing is “400,000 Hiroshima atomic bombs per day”, which comes to 2.51e+19 joules/day.
A watt is a joule per second, so that works out to a constant additional global forcing of 2.91e+14 watts.
Normally, we look at forcings in watts per square metre (W/m2). Total forcing (solar plus longwave) averaged around the globe 24/7 is about 500 watts per square metre.
To convert Hansen’s figures to a per-square-metre value, the global surface area is 5.11e+14 square metres … which means that Hansens dreaded 400,000 Hiroshima bombs per day works out to 0.6 watts per square metre … in other words, Hansen wants us to be very afraid because of a claimed imbalance of six tenths of a watt per square metre in a system where the downwelling radiation is half a kilowatt per square metre … we cannot even measure the radiation to that kind of accuracy.
So imagine the output of a 0.6 watt light bulb in a standard Edison base such as at right, with 1/100th the power of a common household 60 watt light bulb.
Could you even see its output?
And, more importantly, can that 0.6 watt of energy imbalance even be accurately measured on a global basis?
As Dr. Judith Curry points out, the paper An update on Earth’s energy balance in light of the latest global observations by Stephens et al. says this about down-welling long wave infrared radiation (what CO2 affects) and that 0.6 watts of imbalance on the surface that Hansen claims:
Note the figure on the Earth that I highlighted in yellow: Surface imbalance 0.6±17
That’s an uncertainty of 17 watts, or if you prefer Hansen-Cook parlance, 4 Hiroshima Atomic bombs an uncertainty of ±113 Hiroshima bombs every second.
The ±17 watts uncertainty of the 0.6 watt surface imbalance is two orders of magnitude larger than the claim! But, activists like Cook say global warming will “Cook’ us for sure.
Hmmm. Something bigger is needed to keep it scary. How about comparing Hiroshima bombs to the biggest fusion bomb in the solar system, the sun? From our article:
The Hiroshima bomb released ~ 67 TeraJoules (TJ) = 6E13J. source
The earths circular area is 3 * (6E6m)^2 = 1E14m2.
The suns TSI is ~ 1kW = 1E3 J/s, so the earth gets ca 1E17 J/s on the sunlit side, so the sun explodes about 1E17/6E13 = 1E3 Hiroshima atomic bombs on this planet EVERY SECOND.
(h/t to bvdeenen)
Gosh, a thousand Hiroshima bombs exploding on this planet every second? How frightening! With that sort of threat, one wonders why Obama isn’t going to announce taxing the sun into submission next Tuesday.
These calculation just go to illustrate that in the grand scheme of things, not only is the global energy associated with global warming small, it isn’t even within the bounds of measurement certainty.
Da bomb, it isn’t. Time to ‘Cook’ up a new scare story.
Here’s the funny thing though, as Donna Laframboise points out, in addition to the laughable statement that Cook plagiarized from Hansen above, somehow the amazing “postdoctoral fellow” without a PhD has somehow been elevated to the status of “climate scientist” by the French in a recent article. Climate Change Likened to Atom Bomb by Scientists.
Although that article talks about “climate scientists” it names and quotes exactly one person – Cook himself. Moreover, the claims here are nothing short of fantastical. It says that climate scientists
have given figures of rising and changing climate. These figures are almost like a warning that states that escalating temperatures are equivalent to four Hiroshima bombs in a week.
They’ve completely attributed the condition to human actions.
It’s clear that this reporter’s first language is not English, so I’m sure she has misunderstood. No official document of which I’m aware has declared humans 100% responsible for current temperature trends (see, for example, the discussion here).
Gotta love it, cartoonist turned “climate scientist”. It’s Da bomb.
Thank goodness for The Pause.
UPDATE: Jo Nova also has a essay on the subject here: http://joannenova.com.au/2013/06/climate-scientists-move-to-atom-bomb-number-system-give-up-on-exponentials/