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:
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.)
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.
So, increased humidity will mean warmer nights…especially in cities where the concentration of H2O producing vehicles would be high.
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
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.