Has Anthony Watts ever heard about the water cycle? Does he know that water lasts in the atmosphere somewhere between hours and days at the most?
Does Anthony know the chemical reaction that occurs when you burn fossil fuels?
Today he wrote about some new catalyst (using carbon nanotubes) that could be used to produce hydrogen as fuel (archived here). That's semi interesting - these things take time to see if they are worth developing further and then commercialising. What got me was first of all was the WUWT headline:
The law of unintended consequences in action: Imagine replacing all CO2 emissions with H2O emissions
And then a couple of comments he made:
Imagine in a hyrdogen powered economy, millions of vehicles emitting water vapor from tailpipes instead of CO2. The panic over temperature from water vapor emissions, which can be double to triple the heat trapping capacity of Carbon Dioxide, would be quite something to watch.
Perhaps he should have tried to do a bit of research first. Even the unreliable Yahoo has some answers.
Does Anthony realise that burning hydrocarbon produces more water per hydrocarbon molecule than "burning" hydrogen produces per hydrogen molecule?
What does he think the mist is coming from cars in cold weather? (Recall denier gripes about photos of power stations.)
For example, with methane:
CH4 + 2O2 → 2H2O + CO2 + energy
With hydrogen:
2H2 + O2 → 2H2O + energy
.The hydrogen would be produced, using a catalyst, from water. I found a fairly simple description of catalysis of the reverse of the above for producing hydrogen for fuel cells.
From the WUWT comments
I'll add some when they appear. Okay, there are a few already. Here's one where Anthony makes another comment, pointing out why deserts get cold at night! You can't fool Anthony Watts. No way :D Barium says:
July 14, 2014 at 2:38 pm
This article is hilarious. Water vapor does not have nearly the same lifespan in the atmosphere as CO2 or methane; it’s on the order of days vs. 10s or 100s of years. The contribution of water vapor, emitted from vehicles, would be miniscule (do you have any idea how much water evaporates from the oceans every day?) I’m not saying H2 is the fuel of the future, but let’s get the science right (or at least tell the whole story).
REPLY: No disputing water vapor has a shorter lifetime than CO2, but if it is actively being cycled into the air locally and continuously, the effects will be an increased local humidity. I think you missed the premise at the beginning from the complaint by Freedman – imagine all that extra water vapor in a city like New York. It will have an effect.
It is well known that the heat capacity of air is dramatically higher when it is more humid. Overnight temperatures are significantly affected, which is why deserts have such wide diurnal range in temperature, due to such low water vaopr capacity.
DESERTS ARE COLD AT NIGHT: Because of the lack of water in the ground, and little water vapor in the air, most deserts can get quite cool at night. This is because (1) dry ground does not retain as much heat as moist ground, and (2) water vapor is the most important greenhouse gas, so dry air allows the surface to cool rapidly at night through loss of infrared radiation to outer space.
In fact, it has been calculated that the Sahara Desert actually loses more infrared radiation than it gains solar radiation from the sun. This net loss of radiant energy is balanced by the sinking air over the desert, which warms as it is compressed.
Source: http://www.weatherquestions.com/Why_are_deserts_so_hot.htm
So, increased humidity will mean warmer nights…especially in cities where the concentration of H2O producing vehicles would be high.
-Anthony
TedL raises the issue of how leaked hydrogen may affect the stratosphere and says:
July 14, 2014 at 2:47 pmI looked and found something on this topic. It looks as if replacing hydrocarbons with hydrogen would have a beneficial effect all round (my bold italics).
If we start using hydrogen gas in quantity we will see leakage at all the transfer points – production, transportation, delivery – just like natural gas. Unlike natural gas hydrogen is a much smaller molecule and leaks much more easily. It is lighter than air, which means it will rise through the atmosphere until it reaches the stratosphere where it will find the ozone layer. Ozone is highly reactive – the hydrogen will react with the ozone forming water vapor – simultaneously depleting the ozone and creating a stratospheric clouds of ice crystals, which I believe has the potential to change the Earth’s albedo, with a whole bunch of unintended consequences.
With respect to the second topic, converting the world’s fossil-fuel onroad vehicles (FFOV) to hydrogen fuel cell vehicles (HFCV), where the hydrogen is produced by wind-powered electrolysis, should reverse observed trends in tropospheric global warming and stratospheric cooling and reduce anthropogenic aerosol particle emissions reaching the stratosphere. The resulting stratospheric aerosol and ice cloud reductions should decrease heterogeneous chemical loss of ozone, speeding recovery of the stratospheric ozone layer. These results differ from those of a previous analysis that considered the effects on stratospheric ozone of adding leaked hydrogen without reducing gas or particle emissions from FFOV. Wind-powered HFCV should also reduce tropospheric methane by reducing its emissions, reduce tropospheric ozone, and displace essentially equivalent emissions of water vapor and hydrogen currently emitted by FFOV. The climate and ozone-layer benefits of battery-electric vehicles, where the electricity is derived from noncombusting renewable energy, should be similar to those of wind-powered HFCV.
It took a little while before someone pointed out that burning any hydrocarbon produces water. John M says, referring to Anthony's original version of the equation:
July 14, 2014 at 2:51 pm
Correct reaction is
H2 + 1/2 O2 = H2O
or
2H2 + O2 = 2 H2O
Also, fossil fuels make plenty of H2O when they burn. Have to do the math on a per-kJ basis though.
Alan Robertson was close behind and says:
July 14, 2014 at 2:52 pm
Burning any hydrocarbon fuel releases H2O.
Ralph Dave Westfall also corrects Anthony's original equation and says:
July 14, 2014 at 3:00 pm
Author needs to fix the equation. It should be 2H2 + O2 –> 2H2O + heat.
I've tried to explain at WUWT that H2O emissions can't force the climate because of "rain". Obviously, I failed to communicate. Again.
ReplyDeleteI liked Smokey's comment that you were "getting an education" - yeah, right. As if you didn't already know just how ignorant is the average person at WUWT about all things climate.
DeleteEvery visit to WUWT is an educational experience, watching them go even lower in their never-ending limbo contest of scientific illiteracy.
DeleteI just noticed that you included Anthony's response to Barium's valid point, which was repeated by others including Evan Jones, who deserve kudos for trying.
Anthony Watts doesn't acknowledge that replacing all CO2 emissions with H2O emissions would reduce AGW, rather than increasing it like he originally implied by citing Trenberth's global and thus irrelevant estimate. In fact, he appears to be reduced to saying that H2O emissions would only have local effects near cities in deserts. Isn't that really similar to the local heat island effect that he's spent the last few years trying to distinguish from AGW? (In the mistaken impression that scientists hadn't already done that. Ad nauseum.)
You say
ReplyDelete"burning hydrocarbon produces more water per hydrocarbon molecule than "burning" hydrogen produces per hydrogen molecule?"
While this is beside the point, still, doing a comparison per molecule of fuel isn't obviously meaningful. Instead, you'd compare the amount of water released, per unit of energy released - exactly as you quote JohnM as saying. And assuming the efficiencies of the combustion engine and the fuel cell were different, you'd have to toss in the different efficiencies as well.
Fair enough, especially if you're worried about water warming. How about doing it and letting us all know the result.
Deletehttp://en.m.wikipedia.org/wiki/Heat_of_combustion#Heat_of_combustion_tables
DeletePer mol, methane is triple the energy, so you need to burn 3H2 to match the energy of CH4, which means 50% more water per joule for H2 rather than CH4.
That's per joule of heat from combustion; then there's the efficiency of your engine.
The only semi-serious plan I know of to fly planes off H2 is because they need H2/O2 propellant once they get out of the atmosphere, so you might as well use H2 and air within the atmosphere.
I have a hard time believing that weather presenter Anthony Watts really never heard of rain. Does he really think it is so easy to change the relative humidity of the atmosphere and that this additional moisture would not rain out?
ReplyDeleteAt least Evan Jones get it.
Ken Hall says: "Isn’t water vapour 20 times more potent a greenhouse gas than CO2? Wouldn’t that be bad? MmmmKay?"
evanmjones says: "Not on a molecule-to-molecule basis. More important, H2O has almost zero persistence, while CO2 has a very long persistence."
Nick Stokes says: [snip - off topic - this thread is about water vapor, not methane -mod]
I wonder whether Nick Stokes tried to point out that while contrary to AGW the concern for the ozone layer is real, it is easy to show that the hydrogen fluxes and effects are much smaller than those of methane. And that the effect of hydrogen is thus small.
Wish I'd seen this before I commented above. Yes, Evan Jones and Barium et al. seem to get this. Kudos to them. I'm also curious to see what Nick wrote. Maybe he'll post his comment at his blog...
DeleteDon't take this the wrong way, people. In fact you're probably right to offer congratulations.
ReplyDeleteBut that's what I find most damning of WUWT. To think that anyone would feel compelled to congratulate commenters on the "world's most viewed climate blog" for:
a) pointing out that burning hydrocarbons releases water, or
b) pointing out that it rains, or even for
c) pointing out that there's a heap more water in the air already than CO2. What does Anthony think? We're going to double H2O by burning hydrogen? WTF!
How could anyone take WUWT seriously when the bar is so abominably low that people feel the need to offer congratulations for stating the glaringly obvious?
Yes, this is why WUWT isn't taken seriously... except in U.S. Congress and some other countries, judging by their actions and words.
DeleteI congratulate anyone who states the glaringly obvious at WUWT, because the response they'll get probably won't be pleasant. Frankly, I don't know how Sou has waded through the WUWT sewer for this long. I suspect Sou has thick skin made of a magical alloy of adamantium, mithril and unobtanium.
Lol. The trick is adding a smidgen of thiotimoline, but careful not to add too much or you shoot through a worm hole and get stuck permanently in the alternate universe :)
DeleteOh, and of course, take extra care when anywhere near H2O.
DeleteHa! Only Sou could make an Asimov reference that I'd need to google.
Delete"It took a little while before someone pointed out that burning any hydrocarbon produces water."
ReplyDeleteActually, it took longer than it should have. I offerred this:
"Barium's right. CO2 stays, water vapor goes. Burning a molecule of methane already produces 2 molecules H2O for each CO2. But we've burnt about 400 Gtons C, and CO2 has gone from 280 to 400 ppm. The water just made it rain somewhere."
My comments now all go in to moderation. What appeared was:
Nick Stokes says:
July 14, 2014 at 4:15 pm
[snip - off topic - this thread is about water vapor, not methane -mod]
Thanks, Nick. I figured it might be something like that. Your comment couldn't have been more "on topic" if you'd tried.
DeletePretty appalling that even the mods of this "award-winning science blog" don't understand the first thing about hydrocarbons or water.
I suppose it shouldn't be a surprise when blog owner Anthony Watts himself is abysmally ignorant.
"It is well known that the heat capacity of air is dramatically higher when it is more humid."
ReplyDelete*facepalm*
The specific humidity of moist air is higher than for dry air, but the effect is small. The difference in heat capacity between bone dry air and oppressively humid air is only a few per cent, not "dramatic." (I suspect that he got the direction of change correct only by accident, and that he wasn't really thinking of stuff like the first law of thermo.)
This is basic thermodynamics of the sort one learns in an intro course for met majors. I think Anthony would like to be taken seriously by the scientific community but he needs to learn the elementary physics bits first.
According to Wikipedia (http://en.wikipedia.org/wiki/Anthony_Watts_%28blogger%29#Early_life_and_education), Watts failed to graduate from college.
ReplyDeleteIn fact (IIRC), he spent something like *7 years* failing to graduate.
Reminds me of John Blutarsky's (John Belushi) classic line in Animal House: "Seven years of college down the drain..."
"Enquiring Minds" would love to see Watts' college transcript!
Why is Watts hiding the data? Show us the transcript!
DeleteThe WUWT post is still not retracted!!
ReplyDelete