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Cities need more trees

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101–110 of 169 posts

Re: Cities need more trees

#102

Earlier quoted context omitted.

If you look at bellevue i personally think it's disgusting, that loveless massive sechseleutenplatz, lot's of cars always using the horn, what a waste of that iconic place constricted between traemli and a always busy street, tbh even Delhi is less stressful, let alone Vienna. EDIT: Do you mean Schwanstadt right? That lovely smell of birdshit in the sommer plus the massive stink of piss and puke after (and up to 10 d…

No, he means "schwammstadt" (sponge city), the concept idea that you need to create the capacity to soak up excess rainfall and store it like a sponge instead of relying on drainage entirely. https://en.wikipedia.org/wiki/Sponge_city

Which isn't a bad idea generally, but for cities like Zurich (and its sister city Geneva which is the same also in this regard) there isn't much need - it sits at the end of a massive lake, most of the city center isn't much higher than lake itself.

Effect of the lake subsides somewhat with distance form it, but it definitely creates its own micro-climate thats always colder and more humid than further away from it. To have more high trees that prevent all that tarmac, concrete and stone from heating up during day is definitely a plus, but these cities are not some scorched Phoenix, AZ equivalent.

Re: Cities need more trees

#103

Earlier quoted context omitted.

Kind of an odd flex given how walkable San Francisco is, but the "risk adversity" is because people actually die. Last year, five people died from fallen trees in a single storm (two in the city).

Mexico City is one of the largest cities in the world. Five people out of 21 million is nothing. Sure, every death is tragic, but there are a lot more efficient ways to spend time and money preventing deaths than tree trimming.

Five deaths in the Bay Area from one storm, two in San Francisco (with a population around 800,000). There were other tree related deaths last year. More to the point, the trees that the city is actively removing are old, mature ficus trees that present a variety of risks (e.g. sidewalks, sewer and other underground utilities), overhead (e.g. public transit) wires.

Re: Cities need more trees

#104
post #98

Earlier quoted context omitted.

Los Angeles is located in semi-arid climate, so there's not going to be a lot of vegetation there.

The Hollywood Hills show that doesn’t have to be the case.

The Hollywood Hills are pretty barren no? There are trees but still very arid and not lush forest.

Re: Cities need more trees

#105

Earlier quoted context omitted.

If you look at bellevue i personally think it's disgusting, that loveless massive sechseleutenplatz, lot's of cars always using the horn, what a waste of that iconic place constricted between traemli and a always busy street, tbh even Delhi is less stressful, let alone Vienna. EDIT: Do you mean Schwanstadt right? That lovely smell of birdshit in the sommer plus the massive stink of piss and puke after (and up to 10 d…

Zürich needs Lärmblitzer against pointless revving and honking.

Or a bridge/tunnel before bellvue, and make the whole bellvue+niederdoerfli up to hauptbahnhof carfree...just imagine that! But yeah you are right with those Lärmblitzer too.

Re: Cities need more trees

#106
post #32

Here in Utrecht the Netherlands they are trying to greenify the city to reduce heat stress during the hot months. They try to plant as much trees and plants as possible, they try not to mow grass often and let it grow, they encourage homes to remove tiled gardens and add green, they have programs to turn roofs into green roofs. I like it, the city feels nicer to life in. https://healthyurbanliving.utrecht.nl/fileadmi…

I live at the boundary between city and forests and in summer the temperature drop is really 'incredible'. The amount of energy wasted by urban areas is as much so. But at the same time it's nice because we can restore more trees for shade easily

I live in foothills of a lower range of hills (European Jura), and it has numerous effects. The air is normally blowing down the mountains towards us in the evening (katabatic wind), so it doesn't matter how hot the day was, evenings are pleasantly cool and night gets colder than expected. This wind also cools hot surfaces pretty effectively.

Even just entering a dense natural forest during the day, one can sense drop in temperature around 3-4C during summer, and increase in humidity during dry periods.

Re: Cities need more trees

#107

Earlier quoted context omitted.

If you look at bellevue i personally think it's disgusting, that loveless massive sechseleutenplatz, lot's of cars always using the horn, what a waste of that iconic place constricted between traemli and a always busy street, tbh even Delhi is less stressful, let alone Vienna. EDIT: Do you mean Schwanstadt right? That lovely smell of birdshit in the sommer plus the massive stink of piss and puke after (and up to 10 d…

No, he means "schwammstadt" (sponge city), the concept idea that you need to create the capacity to soak up excess rainfall and store it like a sponge instead of relying on drainage entirely. https://en.wikipedia.org/wiki/Sponge_city

I'm so old I can still remember when Sechseleuten Square was green grass, now replaced with searing heat assemblers of stone....so even the city is working against that sponge thing, but yeah it sounds good from a politician's mouth.

Re: Cities need more trees

#108
post #102

Earlier quoted context omitted.

No, he means "schwammstadt" (sponge city), the concept idea that you need to create the capacity to soak up excess rainfall and store it like a sponge instead of relying on drainage entirely. https://en.wikipedia.org/wiki/Sponge_city

Which isn't a bad idea generally, but for cities like Zurich (and its sister city Geneva which is the same also in this regard) there isn't much need - it sits at the end of a massive lake, most of the city center isn't much higher than lake itself. Effect of the lake subsides somewhat with distance form it, but it definitely creates its own micro-climate thats always colder and more humid than further away from it.…

Berlin, one of the leading cities in Germany on those concepts is located on two rivers, plenty of canals and between a few lakes. Hamburg is another very active place and it's close to the seaside, with a huge river and plenty of water in the city. A lot of concepts refer back to city planning that Kopenhagen started after a massive rainfall event in 2011 - a city which is fairly flat, has a large river front and plenty of canals.

Still, there's need to evaluate such city planning concepts because the lakes and rivers do not solve all of the problems associated with heavy rainfalls and drought cycles. They do nothing to handle the runoff if you get massive rainfalls in a short period of time because the water management gets overwhelmed. Also, city trees do not benefit substantially from the high ground water level and still suffer in drought.

So while not all of the concepts ideas may be applicable to Berlin, Hamburg, Kopenhagen, Zurich or Geneva, concepts like green roofs, local water storage etc. are still required to respond to the incread frequency of high rainfall events and increasing summer temperatures.

Re: Cities need more trees

#109

Earlier quoted context omitted.

No, he means "schwammstadt" (sponge city), the concept idea that you need to create the capacity to soak up excess rainfall and store it like a sponge instead of relying on drainage entirely. https://en.wikipedia.org/wiki/Sponge_city

I'm so old I can still remember when Sechseleuten Square was green grass, now replaced with searing heat assemblers of stone....so even the city is working against that sponge thing, but yeah it sounds good from a politician's mouth.

It's a relatively novel concept, though the problems of replacing open surfaces with stone slabs and asphalt could have been obvious decades ago :(

Re: Cities need more trees

#110

Spent last week in South California, visiting family. Flying into LAX made me feel like I was flying into a hell scape. From the air, no green was visible for miles. Compared to my home (London, originally Manchester), I thought it not just odd but barely liveable. You could almost the heat off the concrete by looking at it from the air. Driving around as far south as Orange County for the next week I was happily sur…

Next time you visit family get them to rent a house in Santa Barbara. Technically it's "central" California but it's only 90 minutes from LA and it's probably the coolest and most livable place in the whole state.

"only" 90 minutes
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