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Entrepreneurs Fight Air Pollution With CO2-Reducing 'CityTrees' (cnn.com)
CNN is reporting on "CityTree", a unique 10-foot tall mobile installation which removes pollutants from the air." An anonymous reader quotes their report:
Berlin-based Green City Solutions claims its invention has the environmental benefit of up to 275 actual trees. But the CityTree isn't, in fact, a tree at all -- it's a moss culture. "Moss cultures have a much larger leaf surface area than any other plant. That means we can capture more pollutants," said Zhengliang Wu, co-founder of Green City Solutions.
The huge surfaces of moss installed in each tree can remove dust, nitrogen dioxide and ozone gases from the air. The installation is autonomous and requires very little maintenance: solar panels provide electricity, while rainwater is collected into a reservoir and then pumped into the soil... "We also have pollution sensors inside the installation, which help monitor the local air quality and tell us how efficient the tree is." Wu said. Its creators say that each CityTree is able to absorb around 250 grams of particulate matter a day and contributes to the capture of greenhouse gases by removing 240 metric tons of CO2 a year... Wu also argued that the CityTree is just one piece of a larger puzzle. "Our ultimate goal is to incorporate technology from the CityTree into existing buildings," he said.
So far they've installed 20 CityTrees -- each of which costs about $25,000.
The huge surfaces of moss installed in each tree can remove dust, nitrogen dioxide and ozone gases from the air. The installation is autonomous and requires very little maintenance: solar panels provide electricity, while rainwater is collected into a reservoir and then pumped into the soil... "We also have pollution sensors inside the installation, which help monitor the local air quality and tell us how efficient the tree is." Wu said. Its creators say that each CityTree is able to absorb around 250 grams of particulate matter a day and contributes to the capture of greenhouse gases by removing 240 metric tons of CO2 a year... Wu also argued that the CityTree is just one piece of a larger puzzle. "Our ultimate goal is to incorporate technology from the CityTree into existing buildings," he said.
So far they've installed 20 CityTrees -- each of which costs about $25,000.
CO2 is a global problem, not a city problem. There is no reason to locate CO2 consuming moss in any particular location, so it should be where it grows best, which is likely not downtown. This is obvious public "art" to make a statement, and not a serious attempt to mitigate AGW. Anyway, it does look cool.
By the way, surface area is irrelevant if there isn't air flow past the surface, like there would be for an actual tree.
"Nobody is denying that climate change is real."
Hahahahaha.
"Is our country still spending money on the GLOBAL WARMING HOAX?"
-Trump tweet on 25 Jan 2014
"Global warming is an expensive hoax"
- Trump tweet on 29 Jan 2014
"I don’t believe in climate change."
- Trump on CNN's New Day, 24 Sep 2015
This begs the question of whether CO2 is actually a pollutant or not.
No, it raises the question. Begging the question means something completely different.
CO2 is not a pollutant in the normal sense of causing a specific problem where it is concentrated, but in excess it does cause global problems regardless of what you call it.
So, each "citytree" removes 240 metric ton of CO2 a year?
Right.
That's 529,109 pounds of molecular CO2, per year.
What does it do with it all?
Turn it into biomass?
Or unicorns?
If it captures 240 metric tons of CO2 a year, they better have it on a strong foundation. That is going to get really heavy.
There used to be a lot of confusion about how the carbon cycle works but I hoped that we're over that now. In short, plants use up only as much carbon as they need to grow, the rest just goes through them. This installation will never become carbon negative.
It might help with air pollution, but for $25000 apiece planting 275 trees may still be more economical.
Except for the whole lying through his teeth part, which makes up the bulk of both that post and the implication from yours. Look into Svante Arrhenius, the father of physical chemistry. He wrote about the exact chemical processes causing anthropogenic climate change and they are explicitly tied to burning hydrocarbon fuels. Here is a translation of the detailed paper he wrote in 1906 which is an elaboration on his original one in 1896. These mechanisms are the same ones acting now. There is zero ambiguity on the mechanism, and the direct as well as increasingly increasing role of human activity in accelerating global warming.
We wouldn't claim that we did that to the other planets because your assertion is complete bullshit.
I hate to be the bearer of bad news, but something isn't true just because you thought of it.
It is spelled 'Divine' and it is within our control.
God helps those who help themselves
A simpler and cheaper way is to plant ivy. Ivy covered buildings were common 200 years ago.
The percentage of CO2 in the atmosphere is a rounding error compared to water vapor and should have a negligible effect unless it somehow behaves differently than water vapor. I honestly would like to know is C02 that much more potent than water vapor or does it somehow behave differently?
Yes, different gasses have different levels of greenhouse effects. This EPA site shows the relative effect of some of them but doesn't mention water vapor. They call it GHP, or Global Warming Potential. CO2 is the baseline by definition at 1. I think water vapor is excluded because its effects are transient as the amount of water vapor itself fluctuates a lot. It looks like some consider the changes in water vapor a side effect of the other GHGs and that it functions more as a mechanism of warming rather than a cause (that is, change in other GHGs drive changes in water vapor as part of the warming mechanism).
https://www.epa.gov/ghgemissio...
That at least gives you a place to start.
Should be debate flat earthers too? Bafoonery should be called out as such and not given legitimacy.
Alright, time to drive a stake through the heart of this brain-dead water vapor meme.
There's one important fact about water which you are overlooking: it is wet. That is to say it can exist as a liquid (or a solid) at normal atmospheric temperatures and pressures. This means it can't diffuse throughout the entire troposphere like CO2 can before it exits the atmosphere as rain, snow, or dew.
And this is a good thing, because water is a potent greenhouse gas and all things being equal higher temperatures means more evaporation. If evaporation could drive warming the way CO2 does, we'd be looking at a runaway positive feedback loop that would end with the oceans boiling away.
Still, water doesplay a key role in anthropogenic climate change models. That's because CO2 can increase water evaporation in a global way that water vapor itself cannot. Water vapor basically doubles the impact of anthropogenic CO2.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
Should be debate flat earthers too? Bafoonery should be called out as such and not given legitimacy.
Yes. I would gladly give evidence for a circular earth to a legitimate flat earthers just as I routinely give evidence to anti-vaccine people why they should vaccinate and complain to pro-vaccine people that I wish there was better data on the pros and cons of vaccines. Hiding behind the mantra of "the other side is evil and stupid so I won't engage" doesn't help anyone.
Where is all that carbon the moss is sequestering going? 240 metric tons of carbon doesn't just poof into nothingness. 240 metric tons a year is just under a ton a day. Based on the size of these things they should weigh somewhere between 4-8 metric tons. With the figures given they would be doubling in weight every 1-2 weeks from just the carbon. That doesn't sound very autonomous or low maintenance.
The ozone problem and greenhouse gas problem are separate issues. Ozone is a comparably minor greenhouse gas compared to CO2, methane, nitrous oxide and (yes) water.
Ozone depletion in the stratosphere was and is still a major problem, driven largely by part per trillion levels of halocarbons from a variety of man-made emissions. The reason it's not being talked about so much anymore? Because Montreal Protocol regulations worked. CFC concentrations are down and the ozone hole is slowly repairing itself:
https://www.theguardian.com/en...
CO2 is a potent greenhouse gas, and so is water. The difference is that water concentrations are limited in the atmosphere: too much and it becomes a cloud and then rain. CO2 concentrations, on the other hand, can just keep rising.
Without rises in other greenhouse gases, the water concentration is such that the short term global temperature trend would be stable. Instead, since other GHG's are causing further warming, it's allowing more water to be stable in the atmosphere. That's driving global temperatures even further up, resulting in positive feedback. There's a nice ACS article about it here:
https://www.acs.org/content/ac...
The best way to predict the future is to invent it.
You HAD to pick ozone as part of your post? It was a huge problem a few decades ago. Because the world globally decided to ban CFCs usage, it is no longer a major problem. Thou it is still in the process of repairing itself. If we go back to using CFCs, we can mess it up again in 2-3 decades. Sooner since we have so much more industry.
It's pretty much THE perfect example of how humans can easily impact climate change on a global level AND also solve it if they approach it scientifically!
well a few years ago the other planets in the solar system were increasing in temp around the same rate as us.
No, they weren't.
Check your data sources. First, find the actual papers, and verify that in fact other planets in the solar system were not increasing in temperature at around the same rate as us (they weren't, and aren't.)
Then, figure out who told you that and don't ever believe anything they tell you.
Photosynthesis does: CO2 + Water => Sugar + O2...then the plant takes that sugar and turns it into biomass by converting it to starches and structural materials for the plant itself.
Carbon has a molecular weight of 12 and Oxygen is 16...so CO2 is 25% carbon by weight. So to absorb 240 tons of CO2 per year - it's got to be generating (at a minimum) 60 tons of extra plant material per year - and more likely (because dead/living moss isn't all carbon) it's at least twice that.
There is only just so much space in that concrete container - which means that a literal truckload of dead/living moss has to be removed from it every single week! Then, that biomass has to be disposed of in some way that doesn't simply re-release it into the atmosphere when it decays...you'd have to bury it or something.
This is a ridiculous claim - it can't possibly be true. Even 24 tons a year wouldn't be credible - and 2.4 tons a year would seem high...the entire installation would haves to double in size every year to keep up even that more modest amount.
What I'm sure happened here is that it's plausible that the moss has vastly more surface area than a tree - but moss is much more slow-growing than trees are - so the amount of CO2 it absorbs cannot possibly be as much per-unit-area as the leaves of a tree. So I'm betting that they did all of their math from surface area alone - and didn't stop to think beyond that.
This is B.S.
www.sjbaker.org