Rough month: Pollution levels measured at my apartment in Frederiksberg, Copenhagen in November 2019

By acquiring an inexpensive pollution monitoring device, I can now keep track of air pollution outside my home instead of relying on “official sources”, which often just pass the buck, saying that pollution in Copenhagen comes from other countries. I feel empowered.

In my work in urban design I speak about the importance of data in cities and about citizen engagement. I encourage client cities and keynote audiences alike to gather as much data as possible and to enable citizens to have an influence on the development of their streets, neighbourhoods and cities.

I have finally had the opportunity to practice what I preach and equip myself with an Airbox pollution monitoring device to monitor levels of particulate matter from pollution, in particular, levels of dangerous particles less than 2.5 microns (µm) in diameter — known as PM 2.5. These particles are a greater threat to human health because they can travel deeper into the lungs.

The idea for DIY monitoring has been in my head for a few years.

Back in 2011, Copenhagen hosted the world cycling championships and to my surprise, they chose to close off the main boulevard through the city center — Hans Christian Andersen Boulevard — for over a week. Denmark’s busiest and most polluted street, with 60,000 cars a day.

A few months before the event, I had an idea. I thought about the study done after 9/11 where temperatures were measured in the US for the five days that air traffic was grounded in the US. It was an opportunity that wasn’t likely to present itself again. I realised that closing off Copenhagen’s city centre to car traffic wasn’t something that was likely to happen anytime soon — or indeed anything that any other city dared to do — and that it would be a brilliant opportunity to measure pollution levels in the city center before, during and after the event.

I wrote about this in the following link. The main takeaway was the air pollution fell by a whopping 30% after the boulevard was closed off.

Brilliant stuff. Gathering data where no data — or certainly no citizen-led data — was available.

Since then, I harboured a desire to get my own gear. It took a while, but in October 2019, I was in Taipei to film an episode of my TV series about urbanism, The Life-Sized City. One of my guests was Ling-Jyh Chen, research fellow and professor at Academia Sinica. The segment will be about his project to distribute inexpensive Airboxes to citizens and public institutions that enable people to monitor pollution and contribute to a large network of readings and data.

My Edigreen pollution montoring airbox outside my apartment in Frederiksberg, Copenhagen

Christmas came early. I brought an Edigreen Airbox home with me and promptly installed it outside my living room window.

I have lived in this flat in Frederiksberg for about ten years. Early on, I noticed that the windows facing the street are the dirtiest windows I’ve ever had in any flat I’ve lived in in Copenhagen. It’s wild how often I have to wash them. Then I learned that 30,000 cars each day roll past my windows, through the busy intersection the flat faces. So it’s not hard to figure out why my windows get so dirty.

It was pretty easy to set up the Edigreen Airbox and connect it to my wifi and start measuring. I am constantly checking the map to see what the current readings are (when you click on the link, you are automatically centered on Taiwan, where most Airboxes are located, so I have to zoom out and get over to Denmark) and I also use the app when I’m on the road. If you click and go to Denmark, there’s only one Airbox in the country at the moment, so that’s me. The Airbox takes a reading every five minutes.

The program has a website with information but it also generates graphs of your data over the last month, which is what you saw at the top of this article.

On this direct link, you can the data from my Airbox right now.

The levels of PM 2.5 should not exceed 25 micrograms per cubic meter (μg/m3) on a daily basis. On the above graph, you can see that November 2019 was a pretty rough month in Copenhagen. There were more days where PM 2.5 levels exceeded the acceptable levels that not.

The narrative is that most pollution comes from sources in other countries. Blame Poland and Germany, basically. PM 2.5 particles CAN travel long distances and contribute to the big pollution picture, but after the measurements during the cycling world championships, as well as my filthy windows, we know that local traffic is a major source.

24 hour readings from left for: 07 Nov (07:56), 19 Nov (15:12) and 24 Nov (14:32)

November started out okay, with spikes of pollution. For no other reason that “cosy”, many people still have wood burning stoves in Copenhagen, which are also sources of PM 2.5. This might account for the spike, for example, on the graph at above left, perhaps along with our waste incinerators operating at night.

But as November progressed, things got nasty. There were several days, like the graph above right, where pollution was off the charts. This is nothing we hear about in the news.

Wind direction readings for selected days with high levels of PM 2.5. South, east, northwest.

I checked the wind direction regularly, thinking that the industrial north of Poland and Germany could contribute to the high levels, but through course of the month, especially during the bad days, there was no pattern. The wind came from every direction, which you KNOW it does if you ride a bike in Copenhagen.

I’m still observing the data from the readings and figuring out how best to use it. But just having an Airbox outside my flat is empowering. Access to my own data is cool. The Airbox is portable, too. I can attach a powerbank and get mobile with it, taking readings from anywhere I want.

There are other DIY monitoring systems that have appeared on the market in recent years. An Edigreen Airbox will set you back around $100 but for me, it’s cool to be a part of a huge and growing network of thousands of devices around the world contributing to a pool of data.

It’s important. Outdoor air pollution is a major environmental health problem affecting everyone in low, middle, and high-income countries. Ambient (outdoor) air pollution in both cities and rural areas was estimated to cause 4.2 million premature deaths worldwide per year in 2016. Due in large part to to exposure to small particulate matter, which cause cardiovascular and respiratory disease, and cancers.

Urban playmaker, designer, host of The Life-Sized City tv series about urbanism. Author of “Copenhagenize”. Impatient Idealist.

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