
Newly discovered greenhouse gas '7,000 times more powerful than CO2' - wrongc0ntinent
http://www.theguardian.com/environment/2013/dec/10/new-greenhouse-gas-powerful-chemical-perfluorotributylamine
======
moocowduckquack
Important bit -

 _The study, published in the journal Geophysical Research Letters, found
PFTBA was 7,100 times more powerful at warming the Earth over a 100-year time
span than CO2._

 _Concentrations of PFTBA in the atmosphere are low – 0.18 parts per trillion
in the Toronto area – compared to 400 parts per million for carbon dioxide. So
PFTBA does not in any way displace the burning of fossil fuels such as oil and
coal as the main drivers of climate change._

 _Dr Drew Shindell, a climatologist at Nasa 's Goddard Institute for Space
Studies, said:_

 _" This is a warning to us that this gas could have a very very large impact
on climate change – if there were a lot of it. Since there is not a lot of it
now, we don't have to worry about it at present, but we have to make sure it
doesn't grow and become a very large contributor to global warming."._

edit - is cool research, but the headline here is very badly judged.

~~~
surfmike
Still, if it is in fact 7,1000 more powerful at warming the earth, wouldn't a
concentration of 0.18 ppm have a greater impact on the climate than 400 ppm of
CO2? Not sure if the math is that simple, but it's not obvious to me why there
has to a much greater concentration for us to worry about it compared to CO2.

~~~
srl
Parts per million versus parts per trillion. Assuming the math is that simple
(I think it is), CO2 is the larger contributor by five orders of magnitude.

------
solox3
Semi-offtopic: water vapour is by far the most powerful atmospheric greenhouse
gas per unit volume and as a whole, many times more 'powerful' than CO2.
Hardly anyone mentions it because it is not something we can change.

[https://en.wikipedia.org/wiki/Water_vapor#Water_vapor_in_Ear...](https://en.wikipedia.org/wiki/Water_vapor#Water_vapor_in_Earth.27s_atmosphere)

~~~
scarmig
That's worth some elaboration, though: the water vapor in the atmosphere is
(to a very, incredibly rough approximation) a system where the average global
vapor concentration oscillates tightly around an equilibrium point. More than
that, the average residence time in the atmosphere is a bit over a week. So
when you say we can't change it, it's very true in one sense: if we vaporized
the Mediterranean into the atmosphere, well before a month had gone by it'd
have precipitated back to the liquid state on the Earth's surface.

On the other hand, what you said could be misunderstood to mean that human
activities have no effect on the average water vapor concentrations, and
that'd be inaccurate. The equilibrium point is determined in large part by
global temperatures: the higher they are, the more water vapor is pulled into
the atmosphere. And we do have a mechanism to increase atmospheric
temperatures: CO2.

CO2 by itself is fairly limited in terms of temperatures: doubling its
atmospheric concentrations only increases average global temperatures by about
a degree, which is simple to calculate and more or less undisputed. But what
really kills us (and where uncertainties creep in) is in the positive feedback
loops, the biggest of which is water vapor. A degree increase in temperature
from CO2 alone results in an additional couple degrees of increase in
temperature due to the effects of increased water vapor.

Combine a couple of those positive feedback loops, and you've got a problem.

~~~
logfromblammo
Such as firing the methane clathrate gun.

~~~
scarmig
Yes, but that's almost a separate issue. Water vapor is a limited feedback: if
you double CO2 concentration, the additional water vapor will increase
temperatures further, but only enough to induce a fraction of the original
amount of increased water vapor to be sucked into the atmosphere. If this
weren't the case, small deviations in the amount of water vapor in the
atmosphere would cause even greater deviations, leading to runaway global
warming until other, negative feedbacks grow large enough to counteract it; in
other words, we must be in a stable equilibrium, as an unstable equilibrium
would have already collapsed into a nearby stable one.

Methane clathrate guns aren't the same: the idea there is that we've not
historically explored the relevant parameter landscape (oceanic acidity +
temperatures). People hypothesize that, if we're not careful, we can stumble
into a saddle point where a small delta propels us away from our current
equilibrium and toward one with much higher mean surface temperature.

All of this is to say that water vapor feedbacks are well established, while a
methane clathrate gun is just a speculative hypothesis.

------
ealloc
For comparison, here's one of many online tables of "Global Warming potential"
(GWP) for different chemicals:

[http://unfccc.int/ghg_data/items/3825.php](http://unfccc.int/ghg_data/items/3825.php)

A 100-year GWP of 7000 seems typical for the type of chemical described in the
article. Nevertheless, it's good we are identifying them.

------
tocomment
If the Falcon Heavy can send 14,000 kilograms to Mars [1]. How much warmer
could 14,000 kilograms of this gas make mars? Anyone able to calculate?

[1]
[http://en.wikipedia.org/wiki/Falcon_Heavy](http://en.wikipedia.org/wiki/Falcon_Heavy)

~~~
samatman
This is a many-page plot point in Kim Stanley Robinson's Mars Trilogy. Highly
recommended to all interested in the colonization of Mars.

14,000 kg would be equal to 98,000 tonnes of CO2. Trivial amount of heating,
esp. since atmospheric forcing is weaker on Mars since the Sun is further
away.

~~~
edj
Incidentally the Mars Trilogy is some of the best hard sci-fi out there.
Absolutely not to be missed.

I reread it a year or two back, and it's standing the test of time very well,
in spite of the fact that Red Mars was first published almost 21 years ago and
the story begins in the 2020s.

------
nealabq
Let's say we want to warm Mars. Could we design a benign long-lived super-
greenhouse gas, preferably from H C N and O?

~~~
mathattack
Does Mars have an atmosphere to insert the gas into? How much mass does a
planet need to support an atmosphere? A quick check on Wolfram suggests that
Earth has 10 times the mass of Mars. Does a planet need to be Earth or Venus
sized to hold onto the air?

~~~
mikeash
Mars does have an atmosphere, but it's thin. As for holding onto the air, it
all depends on what kind of timeframe you're talking about. The Moon, for
example, has no atmosphere because it's too small. But if you magicked into an
existence an Earth-like atmosphere on the Moon, it would persist for something
like a million years before it all drifted away. Mars would do even better.
That kind of timescale is probably plenty for human purposes.

~~~
logfromblammo
Earth's retention of its atmosphere also owes a significant amount to its
planetary magnetic field, which deflects solar radiation that would otherwise
energize molecules in the upper atmosphere enough to escape the gravity well.

------
nealabq
Properties of perfluorotributylamine:

[http://www.chemspider.com/Chemical-
Structure.13836523.html](http://www.chemspider.com/Chemical-
Structure.13836523.html)

------
fleitz
Well I've been holding my breath on this whole CO2 thing, can finally take a
sigh of relief and not worry about contributing to global warming.

~~~
Brakenshire
Look again. This gas is present in the atmosphere at 0.2 parts per trillion.
Its effect is insignificant compared to CO2 or CH4.

