Rustling Road trees are being felled right now

[Guest makapaka]

Where did I say it was relevant and the 2016 data wasn't? The only reason we are still talking about the 2011 data is because people keep complaining it was mentioned at all even though it was presented before the 2016 data. Since the 2016 data was referenced on here nobody has suggested that the 2011 is more relevant. I'm confused why you are asserting otherwise.

 

I will repeat what I said in earlier posts. The full 2016 data has not been published and I have been unable to find it. Without this data, it is impossible to say whether or not Sheffield was included in the data, and so is impossible to say where it ranks.

 

It may well rank below the top 12, but equally, it might not have been included and so could still rank in the top three (like it did in 2011). Without the complete data, it is impossible to tell.

 

So the previous poster is wrong to say we are the 3rd most polluted city and that it is "shameful" because it is impossible to tell if this is the case?

 

WHO 2016 data would also appear to support the argument that we are not - but you aren't sure if this report is complete.

 

Yes?

[Flexo 10]

30 police officers... 5:30am pre-dawn raid.... to fell healthy trees.

 

The trees looked really nice.

https://goo.gl/maps/KBioNtGNYoT2

 

Pity they have replaced them with twigs that, according to Cllr Bryan Lodge, will never grow so big.

[Robin-H 11]

So the previous poster is wrong to say we are the 3rd most polluted city and that it is "shameful" because it is impossible to tell if this is the case?

 

WHO 2016 data would also appear to support the argument that we are not - but you aren't sure if this report is complete.

 

Yes?

 

What? You are putting things in quotation marks that neither myself nor anybody else has said. Where has the notion that anything being discussed regarding this has been 'shameful' come from? I honestly don't know what you are talking about.

 

The WHO 2016 data does not support any argument. I have managed to find the full data list for 2016 and Sheffield is not included. It can be downloaded here http://www.who.int/phe/health_topics/outdoorair/databases/cities/en/

 

This means that the most up to date data that I have seen where Sheffield is included in the 2011 WHO data.

[Guest makapaka]

What? You are putting things in quotation marks that neither myself nor anybody else has said. Where has the notion that anything being discussed regarding this has been 'shameful' come from? I honestly don't know what you are talking about.

 

The WHO 2016 data does not support any argument. I have managed to find the full data list for 2016 and Sheffield is not included. It can be downloaded here http://www.who.int/phe/health_topics/outdoorair/databases/cities/en/

 

This means that the most up to date data that I have seen where Sheffield is included in the 2011 WHO data.

 

Post 1219 - poster having said we are 3rd most polluted city refers to it as "shameful". I'm not particularly outraged by that, but I don't expect to be accused of making it up either.

 

It seems that we can't agree on the validity of any report - however we seeming do agree that it's impossible to tell whether we're 3rd or not - so people shouldn't say we are.

 

Yes?

 

Also, the link you have posted looks like a global report taking ambient readings, it doesn't include the ranking of individual cities as per the the other link posted last night for some reason. Where is the report that shoes port talbot top etc? That's not a dig I just wondered why it wasn't there.

Edited March 20, 2017 by makapaka

[Phili Buster 10]

I know mature trees are said to assist with the reduction of air pollution but does anyone know if there is any detrimental effect due to wind calming by the trees (or is there any research)?

On calm days air quality levels fall whereas the levels rise on windy days. I just wondered if there were any scientific studies on the reduction of wind movement by trees and hence the effect upon air quality.

 

Certainly the air quality is a lot better now than in years past. However, if to be believed, some old gardeners believe that the 'pea soupers' of old resulted in better roses due to the sulphur in the atmosphere reducing black spot.

 

As an aside, has there been any research on the difference in pollution levels around the M1 Tinsley roundabout (at the South end of the viaduct) since the traffic light phasing was changed such that there is more stop-start than previously?

[annbaker 10]

I know mature trees are said to assist with the reduction of air pollution but does anyone know if there is any detrimental effect due to wind calming by the trees (or is there any research)?

On calm days air quality levels fall whereas the levels rise on windy days. I just wondered if there were any scientific studies on the reduction of wind movement by trees and hence the effect upon air quality.

 

Certainly the air quality is a lot better now than in years past. However, if to be believed, some old gardeners believe that the 'pea soupers' of old resulted in better roses due to the sulphur in the atmosphere reducing black spot.

 

As an aside, has there been any research on the difference in pollution levels around the M1 Tinsley roundabout (at the South end of the viaduct) since the traffic light phasing was changed such that there is more stop-start than previously?

 

Flying visit before I start the trek home for the day. This should answer your last point Phili Buster. There are monitoring sites all around the city and these are the measurements taken from them

 

https://sheffieldeastend.wordpress.com/air-quality-monitoring-data/abbeydale-road-corridor-community-air-quality-data/

[Robin-H 11]

Post 1219 - poster having said we are 3rd most polluted city refers to it as "shameful". I'm not particularly outraged by that, but I don't expect to be accused of making it up either.

 

It seems that we can't agree on the validity of any report - however we seeming do agree that it's impossible to tell whether we're 3rd or not - so people shouldn't say we are.

 

Yes?

 

Also, the link you have posted looks like a global report taking ambient readings, it doesn't include the ranking of individual cities as per the the other link posted last night for some reason. Where is the report that shoes port talbot top etc? That's not a dig I just wondered why it wasn't there.

 

Sorry I misread that sentence. I thought you were implying that it was shameful to say that Sheffield had the third worst pollution because it was impossible to tell. I think I must have missed out the 'it' when I initially read it, which changes the meaning somewhat. I understand what you were referring to now.

 

The linked page has the data downloadable in database format on the side. It includes the data of the global cities used in the report and includes the UK cities that were mentioned as being the top 12 in this thread. I checked that the data correlated and Port Talbot is in the data (with 25 ug/m3) which is top for the UK. Sheffield is not included in the data.

 

I'm wouldn't necessarily question the validity of either the 2011 or 2016 WHO data. I would assume that both are valid, only that it is not possible to determine a complete ranking of UK cities when both sets of data miss out large cities (such as Manchester in 2011, and Sheffield in 2016).

 

Again, I've never said that Sheffield is third in this regard, and I don't see why it is necessary to be me to join in chastising other users for minor errors.

 

I could see the necessity if somebody was making outlandish claims that were not at all backed up by evidence, but I think the overall point at the annbaker was making remains. The most up to date data that includes Sheffield has it as being one of the most polluted cities in the UK. Maybe it's third, maybe it's joint second.

[Phili Buster 10]

...

 

Thanks for taking time to post link. A little less flying would reduce pollution you know

Edited March 20, 2017 by Phili Buster

[Robin-H 11]

I know mature trees are said to assist with the reduction of air pollution but does anyone know if there is any detrimental effect due to wind calming by the trees (or is there any research)?

On calm days air quality levels fall whereas the levels rise on windy days. I just wondered if there were any scientific studies on the reduction of wind movement by trees and hence the effect upon air quality.

 

Certainly the air quality is a lot better now than in years past. However, if to be believed, some old gardeners believe that the 'pea soupers' of old resulted in better roses due to the sulphur in the atmosphere reducing black spot.

 

As an aside, has there been any research on the difference in pollution levels around the M1 Tinsley roundabout (at the South end of the viaduct) since the traffic light phasing was changed such that there is more stop-start than previously?

 

There was a research paper by Litschke and Kuttler in 2008 entitled 'On the reduction of urban particle concentration by vegetation' that touched on this, in particular reference to street trees and PM10 concentrations.

 

They mentioned the canyon effect, which I believe has been talked about here, and cautioned that where the canopy cover is so dense that particulate matter cannot easily escape and mix with the surrounding atmosphere then localised spikes in PM10 concentration may occur. However, the incidences of this happening are rare, and need a street to have almost complete canopy cover (which I don't believe is the case in any street in Sheffield) and can be mitigated against by proper pruning.

 

The report concluded that despite this increasing canopy cover had the greatest effect in removing PM10 pollution from the atmosphere.

[Longcol 600]

There was a research paper by Litschke and Kuttler in 2008 entitled 'On the reduction of urban particle concentration by vegetation' that touched on this, in particular reference to street trees and PM10 concentrations.

 

They mentioned the canyon effect, which I believe has been talked about here, and cautioned that where the canopy cover is so dense that particulate matter cannot easily escape and mix with the surrounding atmosphere then localised spikes in PM10 concentration may occur. However, the incidences of this happening are rare, and need a street to have almost complete canopy cover (which I don't believe is the case in any street in Sheffield) and can be mitigated against by proper pruning.

 

The report concluded that despite this increasing canopy cover had the greatest effect in removing PM10 pollution from the atmosphere.

 

More specifically they stated;

 

"measurable improvements in air quality can only be achieved by planting large areas of trees with a high filtration effect (e.g. conifers)"

 

https://www.uni-due.de/imperia/md/content/geographie/klimatologie/104_on_the_reduction_of_urban_particle_concentration.pdf

 

Section 6 - Conclusions

[Robin-H 11]

More specifically they stated;

 

"measurable improvements in air quality can only be achieved by planting large areas of trees with a high filtration effect (e.g. conifers)"

 

https://www.uni-due.de/imperia/md/content/geographie/klimatologie/104_on_the_reduction_of_urban_particle_concentration.pdf

 

Section 6 - Conclusions

 

You missed the following paragraph..

 

"According to the studies of FREER-SMITH et al. (2005), filtration effectiveness with respect to smaller particles (PM1) could be about an order of magnitude higher. In that case, smaller, localized areas of vegetation could also be beneficial. Even if they did not bring about any improvement with respect to the statutory concentration standards for PM10, targeted planting campaigns should still be considered in this case, especially in view of the greater significance of PM1 for human health."

[Cyclone 10]

What point are you trying to make longcol? Is it okay to cut down trees for no good reason? Is it justified if trees aren't magically good at preventing flooding or reducing air pollution?