Where do we enjoy the best Air Quality in Greece – and where do we suffer from the worst?

So, let’s have a look at a question that people often make me: where do we breathe the best air in Greece, and where the worse?

The answer is not straight forward and brings some surprises:

Surprise No. 1: Athens is not the most polluted city of Greece. Smaller cities and villages, as well as Patras and Thessaloniki are doing worse than Athens.

Surprise No. 2: the countryside does not always enjoy better air than the cities.

Surprise No. 3: Although the Particulate Matter PM_2,5 on the Greek islands is way lower than on the mainland, the Air on our islands is not as pure as we would like to believe. Read below why.

Surprise No. 4: Within the cities, there are big differences in Air Quality between locations, with some locations that enjoy clean air and some that suffer from very bad air. Even in Athens not far from the center there are lucky citizens that can leave their windows open at night in winter!, something that you can’t really do in most places of a country that is engulfed in a huge wood smoke cloud (yes, I am a bit exaggerating but if you live in Greece you know what I mean…).

The data used to draw these conclusions come from the Purple Air website, which is a platform that collects Air Quality (AQ) data from a network of independent AQ Monitors that are installed in various locations around the country and all around the world (see my first post of this blog about independent AQ monitors here); from the Airly website, which is a similar platform with different AQ Monitors; and from personal observations made with the Flow II portable AQ Monitor. The data used from the Purple Air and Airly AQ Monitors is the yearly average of Particulate Matter PM_2.5, which is a dangerous pollutant that readily enters the lungs and the blood stream creating inflammation and related illnesses all around the body. Let’s not forget that up to 16.600 Greeks die every year because of illnesses related to Air Pollution. In Europe 400.000 people die every year for the same reason, while in the world the death toll of polluted air is over 8 million people/year! Air Pollution is a far bigger killer than COVID-19.

In summary, of all the cities/villages of Greece where there are Purple Air AQ Monitors installed, the winner with the best Air Quality is Skyros, while the overall loser is Ioannina. Athens as a whole enjoys quite a better Air Quality than Ioannina and other cities. If we include data also from the Airly website, we see that Aghios Germanos in Prespa enjoys a fantastic clean air, while Larissa and Kalambaka (Meteora) have a very low AQ, again far worse than Athens.

Ranking of Greek cities/villages’ Air Quality, from best to worst

Rank	City/Village	PM2,5 Yearly Average
1	Skyros	10
2	Platani (village near Rio)	11.3
3	Athens – Vouliagmeni	12.1
4	Ermoupoli – Syros	12.5
5	Athens – University campus	12.7
6	Dyo Choria – Tinos	13
7	Irakleio (Crete)	14.5
8	Athens – Papagou	15.2
9	Nafpaktos	15.2
10	Rio	16.2
11	Antikithira	16.3
12	Athens – Penteli	16.4
13	Athens – Thiseio	16.7
14	Patras – Aghios Andreas	17.1
15	Athens – Marousi	18
16	Thessaloniki – Thermi 1	18
17	Athens – Piraeus	18.3
18	Patras – Trion Navarchon	18.4
19	Athens – Keratsini	18.8
20	Patras – Old Customs	19.6
21	Athens – Chalandri	20.2
22	Alexandroupoli	20.6
23	Athens – Perikleous Str. (Athens centre)	21.2
24	Kalamata Airport	21.4
25	Komotini	21.4
26	Thessaloniki – Nosokomeio Gennimata	22.7
27	Thessaloniki – White Tower	23
28	Patras – New Port	23.2
29	Trikala	23.3
30	Xanthi	23.9
31	Meligalas (Messinia)	24
32	Thessaloniki – Kaminikia, 14th Likeio	24.3
33	Patras centre	25.7
34	Thessaloniki – Plagiari, Pedikos Stathmos	25.7
35	Orestiada	26
36	Thessaloniki – Thermi 2	27.3
37	Skala Messinias	31.5
38	Athens – Nea Irakleio	32.5
39	Ioannina	33.1

The rankings on a map of the country

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We must remind that the above data show us the Air Quality only in those locations where there are Purple Air AQ Monitors installed. So we can’t say with certainty where we can breathe the best Air in Greece and where the worse. Yet, considering also seasonal weather pattern, vehicle traffic, the presence of industry and the effect of household heating we can predict which AQ we can expect also in other parts of the country.

Results explanation

Only a few weeks ago the new World AQ Report for 2020 was published here. With a yearly PM_2,5 average of 18.4 μg/m³, Greece ranked as the 48th most polluted country (of 106) in the world. It was the third most polluted country of the EU, after Bulgaria and Italy. Not a nice news at all… But there is good news too, because compared to the 2019 report, the greek AQ improved from an average of 22.5 μg/m³. Greece was the 36th most polluted country then, and the second most polluted in the EU. The improvement is to be partially attributed to the strict COVID-19 lockdown of last year, but the hope is that the AQ won’t worsen again now.

The Air we breathe in Greece is not healthy, even though it improved last year.

The World Health Organization (WHO) sets the recommended limit for PM2,5 at 10 μg/m³, hence as a whole the country is still breathing an air pollution that is double than the “safe” limit.

Of all locations in Greece, only Skyros complies with the WHO recommendations, while other places suffer from an air pollution that is over three times the safety limits. The EU sets the limit at a less safe limit 25 μg/m³ but this has been recognized as a problem and there are talks to lower it to more strict standards. There are studies that show how just 1 μg/m³ of Air Pollution reduction could save thousands of lives in the UK (which is already way less polluted than Greece!), hence the EU and Greece must seriously work to reduce the air pollution we are forced to breathe every day. See the pictogram here below about Air Pollution in the UK (source here).

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From the Air Pollution data in Greece above we can observe some main features:

1. It looks that Northern Greece has a worse PM_2,5 Air Quality than the southern part of the country. There are exceptions, as we can observe in the Messinian Plain, in the central, western and northern part of the Athens Plain, and in central Patras. These places have very bad air too.

Let’s cut it straight from the beginning, because this is the main problem that the country faces in terms of Air Pollution: the biggest culprit that puts the country among the most polluted in Europe and around half a way in the world, is WOOD SMOKE.

You can practically explain all the Air Quality issues seen on the map above by considering how wood is used by Greek citizens.

Wood is mainly burnt for two reasons: for residential heating in winter and for clearing of the fields from tree branches that are cut every season in olive fields, and in fruit trees orchards for example. Considering that Greece is an agricultural country that produces tons and tons of the best olive oil of the world and the best citruses, peaches and so on, huge amounts of wood are burnt each season in the fields. The biggest branches are not burnt in the fields but are kept and stored as wood for the winter, which ends up in mostly uncertified, old style wood stoves and fireplaces in all villages and cities. WOOD SMOKE is a constant presence in the countryside in Greece from the 1st of October to the end of April. And unfortunately it is so also in villages and cities, including the biggest ones of Athens, Thessaloniki and Patras.

It is because of wood smoke that the small village of Skala, in the Messinian Plain in the S Peloponnese, which is all covered by olive groves with the best olives of the country, has the third worst Air Quality rank in the country. In winter, it has smoke levels so high that PM_2,5 reaches up to 600 μg/m₃ in cold nights. During the day, farmers burn olive tree branches allover the plain, and as a result wood smoke never clears from the villages except during very windy days.

And it is because of wood smoke that Ioannina is Purple Air worst city  (but there are other cities as bad, like Larissa, Kalambaka, Florina, Kozani, Grevena, etc. where there are no Purple Air AQ Monitors to let us know the data). Ioannina is especially unlucky because it suffers from high humidity and foggy days in winter do to the presence of the Pamvotida lake (which in itself is polluted too, unfortunately). As a result, high wood smoke production and high humidity mean very bad AQ (see my post on this subject here).

Big cities like Patras, Thessaloniki and Athens choke in wood smoke every single night in winter too. But Athens enjoys a better AQ because it is more windy in general, so the air remains stuck on the city for less days than in Thessaloniki for example.

Athens shows big differences in Air Quality in its various municipalities, and this is due to two main factors: its geography and the quantity of wood/ oil burners vs. gas burners present in the municipality. As such, geography dictates that the central, western and northern municipalities, which also burn very much wood and oil for heating in winter, are the most polluted (the table above tells us that Nea Irakleio has the second most polluted Air in Greece), while the eastern and southern parts of the plain are the cleanest. People living in Aghia Paraskevi, Cholargos, Ano Papagou and around the university of Athens are the lucky winners! When the air in the rest of Athens in a normal winter night is so unhealthy that you must close yourself inside like a rat in its burrow, people of Cholargos and Aghia Paraskevi don’t have to think it twice to open the window to breathe fresh air as they don’t smell a single drop of wood smoke. Why is this? Because first of all most of the houses there have installed gas burners, so they don’t need to burn wood to keep warm, but especially because they live at the feet of the western slopes of Mt. Hymittos, from which a gentle breeze descends at night keeping away the fumes produced in the rest of the city. The table above tells us that these municipalities have among the cleanest air in the whole of Greece, even better than in some islands! Isn’t this incredible when we think that Nea Irakleio, with one of the worst air of the country, is just a couple of kilometers away within the same city?

2. The islands do enjoy a quite better air than the mainland. This is logic, because they have much smaller populations and in general they are much more ventilated. So, even though people burn wood and oil on the islands too to keep warm, the quantity of smoke produced is far less than on the mainland and usually the wind clears it faster.

So why do I say in Surprise No. 3 that the islands don’t have that perfectly clean air as we would like to think? Because PM_2,5 is not the only bad guy in town.

Like most of Greeks, I and my family like to go to the islands during the summer holiday, and at Easter. We go to Tinos, a wonderful islands in the northern Cyclades. I installed a Purple Air AQ monitor there, in the village of Dyo Choria, which is the highest village of the island lying at 400 m above sea level. I expected to have fantastic clean air up there because there is hardly a day without wind, all year round. Yet, I made a very big discovery: while Pm_2,5 is indeed very low for most of the year, excluding the few windless evenings in winter when some wood smoke from the houses of the few residents can get stuck over the village for a while, or when farmers burn branches during the day, I found out that the levels of NO₂ there are way out off the chart! I couldn’t believe my portable Flow II AQ monitor. I actually didn’t believe it the first year that I used it. So the next year I took with me another Flow II thinking that the first one was faulty. Yet, the same high NO₂ was detected again. How is this possible??? NO₂ is mainly produced by the burning of fossil fuels in combustion engines of cars, trucks, etc. Diesel engines are especially bad for that. But Dyo Choria has so little car traffic, and the house is so far from the road, so where was all that NO₂ coming from?

And the answer is: not from Tinos!!!

Have a look at this image from the Windy website:

The screenshot shows how far NO₂ can travel from its source. We can clearly see that today the NO₂ produced in Athens is crossing the Aegean Sea towards the Sea of Marmara and Instanbul carried by the SW winds. In summer, high concentrations of NO₂ from Istanbul, Izmir and Athens are funneled over the Aegean islands by the Meltemi wind. Hence, even though the islands enjoy a PM2,5 pollution lower than the mainland, they still have a very high NO₂ pollution that is carried to them from the far, big cities of the region. NO₂ reacts with Volatile Organic Compounds (VOCs) in the presence of daylight to produce Ozone (O₃), and both NO₂ and O₃ are dangerous gases at high concentrations. Unfortunately Athens and Istanbul are among the most polluted cities in Europe (and Turkey) in regards to these two gases, and the Greek islands suffer much from that.

The bottom line is that it is very difficult to escape from Air pollution once it is produced. Even if the wind blows it away, you are always downwind in a way and you end up breathing the Air Pollution produced by others upwind.

Greece could greatly improve its Air Quality if the government finally decided to implement measures to make people stop burning wood – both for heating and in the fields – and oil in old heating systems (even coal is still used for heating in the coal villages of W Macedonia!). Household heating in winter is the main Air polluter in Greece, and acting on this would greatly benefit everyone.

As a final remark, some cities are not mentioned in this article because they have no Purple Air AQ Monitors installed. One of these is Volos, which suffers from very bad AQ due to the incineration of rubbish from a cement factory in the outskirts of the city. The issue has been treated in this blog previously here. On the positive side, we must say that Volos has the most Air Pollution-conscious population of the country because of this problem, and my wish is that their example in the struggle to breathe cleaner air is going to be followed by other citizens around the country. People must get informed and act, because we are not breathing clean air in Greece, and 16.600 dead people/year because of Air Pollution are really too many.