Prague considering long-term measures to combat impacts of climate change
The increasingly frequent occurrence of floods, droughts and extreme heatwaves in the past decade have led the Czech government and local administrations to consider long-term measures to moderate the impact of these excesses. The Prague City Council is currently debating a long-term strategy that should gradually prepare the capital for the inevitable impacts of climate change. I spoke to Klara Sutlovicova from the Prague-based environmental think tank Glopolis about the measures that would be most effective and what other cities are doing to protect their inhabitants.
And higher temperatures, especially in the big cities…
“Yes, definitely, a rise in temperatures is something Prague will have to cope with in the future. In the past we have observed an average warming of about one degree Celsius, but it is expected that by the middle of the century the average temperature could rise by 1 to 2.5 degrees Celsius. So higher temperatures is also something that cities will need to adapt to.”
So what kind of measures are we talking about here – more greenery, materials for roads and buildings that deflect the sun’s rays and do not accumulate heat – lighter colours?
“That’s right, all those measures could help cities cope with higher temperatures. And other measures involve things like using water more smartly in cities. Water problems are the major cause for concern in cities around the world, so a smarter use of water would involve using grey water for example for flushing the toilet, a policy that we do not use drinking water for things that do not require absolutely clean water and so on. Also cities need to create better conditions for precipitation. When the rain comes it should be soaked up by the green parts of the city and stay there. So all kinds of measures that would keep the water where it falls are very helpful.”
Well, more greenery seems to be the easiest and most obvious measure – what’s preventing more greenery in Prague – for instance is there available space for more parks or garden colonies?
“The biggest threat for Prague is related to water –too much water in the case of floods, or too little water in the case of long-term droughts.”
“I wouldn’t say that there is not enough space. There is definitely space for more parks or even single trees planted on the streets, but the problem is that it is not being planned properly. So we need better planning and really taking into account that even a single tree could be very helpful for creating better climate conditions. For example in the planning of a parking lot….a parking lot does not necessarily need to be only a stretch of grey asphalt, there can be trees there, parts of the parking lot can be dedicated to green areas where rain water could be soaked up. These things are manageable and we could have them. The reason we do not is lack of planning.”
So why has it not been done? Does not one bother to take these things into account or is it about money?
“It is actually not about money that much, it is more that architects and engineers don’t take these things too much into account. For example when architects draw buildings they do not plan for things that would prevent such buildings from overheating in the summer season. They don’t like it. They don’t like external shading for example, the consider it too ugly, not aesthetic. They care more about how the building looks than if it will not be too hot there in the summer for its inhabitants. So they do not properly take into account that people will spend 90 percent of their time in the building and would like to have good conditions all-year-round for working and living.”
One of the proposals being debated is green roofs, more green roofs. Some even say they should be compulsory on bigger buildings…what do you think?
What about materials for roads and buildings that deflate the sun’s rays, that do not accumulate heat…should that gradually be introduced? It is difficult with the buildings that are already standing….and the use of lighter colours –are these things important?
“Yes, colours definitely play a role. We can all feel that, when you wear dark colours on a sunny day you feel different that if you were wearing light colours. So with new buildings these measures could be easily implemented – if architects and planners keep that in mind. And the same applies to asphalt, there are lighter colours of asphalt that can be used and I even heard of asphalt that can soak up water. This sounds strange, but if such a material is available then why not go for it?”
So basically, anything done in the future should be done with these new materials?
“Yes, and it is actually compulsory in some cities. For example I heard that in Tel Aviv, in Israel, light colours are favoured and are even to some extent compulsory for planners and constructors. The same goes for cars – if you have a white car it heats up much less than a dark car. So these things may sound like little things but they can do a good service when applied in an integrated manner.”
Do we seek inspiration from abroad, from other cities as regards suitable measures?
“When architects draw buildings they do not plan for elements that would prevent such buildings from overheating in the summer season.”
“There are definitely good examples all around the world of cities trying to adapt to global warming and how they integrate the adaptation measures with reducing their carbon footprint. This is also an important aspect of the planning process because obviously the more efficient the buildings or the transport services are, the less carbon the city emits and the less warming we can expect. Buildings and the construction sectors are globally responsible for 40 percent of the overall energy use so this is another example of how important it is to reduce energy consumption in the big cities and it is the reason why many of them combine adaptation measures with measures to cut emissions. For example, in the transport sector it can be electric vehicles, powered by renewable electricity, in terms of building management we have to look at how the buildings could be better insulated, so they don’t need any artificial energy. This applies not only to the winter season when we need heating in our conditions, but to the summer season when the easiest measure is to install artificial air conditioning. But air-conditioning also consumes energy, while if you plan the building smartly, have it well insulated, install external shading, then you will not need external artificial cooling."