Clean city air by public buses

It is a known fact that air pollution poses a major risk to our health and the environment. However, the level of air pollution in many world metropolises appears to be improving only marginally. The World Health Organization (WHO) estimates that approximately seven million people die every year as a result of exposure to harmful substances in the air (WHO, 2018). In many countries, the levels of air pollution exceed the highest values defined by the WHO guidelines as the following figure shows.

According to the WHO definition, air pollution is a contamination of the outside air, that occurs when pollutants or mixtures of it are present in the air for long periods of time, which can be harmful to humans, animals, plants and materials. These pollutants are divided into “particulate matter”, “nitrogen oxides” and “ground-level ozone” (WHO, 2018).

Particulate matter is a complex mixture of tiny particles that can float for a long time in the atmosphere and is divided into 3 different sizes: PM10, PM2.5 and PM0.1. The fine dust is expressed in micrometers and the smaller they are, the deeper it can enter into organisms through inhalation (inVENTer, o.J.). The main causes are man-made emissions from combustion processes in motorized traffic (especially diesel), power generation from coal-fired power plants, abrasion from rail transport and emissions from stoves and heating in households (luftbewusst, n.y.). These particles can cause diseases of the respiratory and cardiovascular systems, increase mortality and cancer risk, plus damage the ground and plants (BAFU, 2018).

Nitrogen oxide is a gas that is generated as a product of unwanted side-effects of combustion processes. Furthermore, nitrogen oxide is an important precursor of ground-level ozone. The main sources of these pollutants are combustion engines and combustion plants for coal, oil, gas, wood and waste. This gas can cause a wide variety of damages to plants and sensitive ecosystems, irritation of the eyes, respiratory organs and skin, including respiratory diseases.

Ozone is a natural component of air, which at the height of the stratosphere, it protects against harmful UV radiation. Located near the ground, it forms an invisible aggressive irritant gas that is harmful to health and the environment. Ground-level, Ozone is formed in bright weather under the influence of sunlight from precursor pollutants such as nitrogen oxides or volatile organic compounds. This condition, mostly prevails in cities in high summer, which led to the term “summer smog” (Stähelin, 2014). Ground-level ozone can irritate the mucous membrane of the respiratory tract, reduce the performance of the lungs and cause damage to plants. It also shares responsibility for the greenhouse effect (BAFU, 2015).

Another term that is very important in this context is the word “smog”, which refers to a phenomenon of extreme air pollution. It is caused by an excessively high concentration of air pollutants and a simultaneously acting weather situation, which prevents the dispersion of air pollutants and accumulates them in the form of a dense smoky fog in the surrounding area, mostly metropolis. A distinction is made here between winter and summer smog. Winter smog is mainly caused by inversion, this is when a warm layer of air lies above a cold layer of air. This acts like a lid that prevents the lower air layers from mixing with the upper air layers. Thereby, the pollutants accumulate under the inversion. The visible haze under the inversion consists primarily of fine dust. The dangerous aspect of this phenomenon is that it increases the toxic effects (Luftlabor, 2015).

The previous chart clearly illustrates that motorized traffic is one of the biggest sources of air pollution. In spite of more emission efficient cars, this problem seems to be increasing as transport network in many metropolises is on the verge of collapse. There are a number of measures that can be taken to achieve sustainable improvements in air quality. Particularly, the promising pilot project of the “air filtering bus” deserves a closer look.

This pioneer idea aimed to improving urban air quality, was recently launched in the city of Southampton, one of the most polluted cities in the UK. The transport company “Go Ahead” has equipped a prototype with a specially designed air filter attachment. This filter was created by the company “Pall Aerospace”, the world’s largest company for filtration in the field of aircraft, ships and defense. The idea behind it, the filter which is positioned on the bus roof absorbs the air out of the environment during the journey and filters out ultra-fine particles. At the same time, it releases filtered clean air. The following figure visualizes this procedure.
The filter is so efficient that it removes 99.5% of the fine particles. According to Go Ahead, the air can be cleaned 1.7 times a year at a height of 10 meters on the used route. Furthermore, the filter has no negative effects on passengers. If all Go Ahead buses were equipped with this technology, the air in Southampton could be cleaned 16 times a year (The Go-Ahead Group, 2018).

This concept can be the solution for combating air pollution in cities such as Beijing or Los Angeles, which are constantly affected by smog, especially in the short-term view as it is simple to implement. In order to make it as sustainable as possible, emission-free buses should be used. The aim is, to gradually equip the entire public transport system with such filters and to make it as emission-low as possible. In order to ensure the best possible long-term impact, the government should create incentives for citizens consciously refrain from using cars and to implement laws banning diesel cars as well as general car bans in city centers.

Take a calm deep breath, because as we see, there exists already good implementable solutions for this problem. It may well be that we will soon see such buses passing by.

 

Sources:

BAFU, 2015. Bundesamt für Umwelt (BAFU). [Online]
Available at: https://www.bafu.admin.ch/bafu/de/home/themen/chemikalien/schadstoffglossar/ozon.html
[Accessed 13 October 2018].

BAFU, 2018. Bundesamt für Umwelt (BAFU). [Online]
Available at: https://www.bafu.admin.ch/bafu/de/home/themen/chemikalien/schadstoffglossar/feinstaub.html
[Accessed 13 October 2018].

BAFU, 2018. Bundesamt für Umwelt (BAFU). [Online]
Available at: https://www.bafu.admin.ch/bafu/de/home/themen/chemikalien/schadstoffglossar/stickstoffoxide.html
[Accessed 10 October 2018].

Department for Environment Food & Rural Affairs, 2017. Department for Environment Food & Rural Affairs. [Online]
Available at: https://uk-air.defra.gov.uk/library/annualreport/viewonline?year=2016_issue_2#report_pdf
[Accessed 13 October 2018].

Galileo, 2018. ProSieben. [Online]
Available at: https://www.prosieben.ch/tv/galileo/videos/2018310-saubere-sache-bus-reinigt-luft-clip
[Accessed 18 October 2018].

inVENTer, o.J.. inVENTer GmbH. [Online]
Available at: https://www.inventer.de/wissen/luftqualitaet-gesundheit/luftverschmutzung-durch-smog-und-feinstaub/
[Accessed 13 October 2018].

luftbewusst, n.y.. luftbewusst.de. [Online]
Available at: https://luftbewusst.de/umwelt/was-ist-feinstaub/
[Accessed 13 October 2018].

Luftlabor, 2015. Luftlabor. [Online]
Available at: http://luftlabor.ch/wintersmog
[Accessed October 2018].

Roser, H. R. a. M., 2017. Our World in Data. [Online]
Available at: https://ourworldindata.org/air-pollution
[Accessed 13 October 2018].

Stähelin, J., 2014. ETH Zurich. [Online]
Available at: https://www.ethz.ch/en/news-and-events/eth-news/news/2014/09/bodennahes-ozon-smog-verursachender-luftschadstoff.html
[Accessed 10 Oktober 2018].

The Go-Ahead Group, 2018. Go-Ahead. [Online]
Available at: https://www.go-ahead.com/en/media/news/2018/GAG-pollution-busting-bus.html
[Accessed 18 October 2018].

The World Bank , 2018. The World Bank. [Online]
Available at: http://databank.worldbank.org/data/reports.aspx?source=2&series=EN.ATM.PM25.MC.ZS#
[Accessed 13 Oktober 2018].

WHO, 2018. World Health Organization (WHO). [Online]
Available at: http://www.who.int/airpollution/en/
[Accessed 6 October 2018].

 

 

What fish did you eat lately?

Overfishing is a vast and extremely growing risk for our highly sensitive eco-system. The world faces the enormous challenge of having to provide food to a population well in excess of 9 billion people by the middle of the twenty-first-century. The growing population explains the all-time high resulted in 2016 of 171 million tonnes of fish taken out of our oceans, of which 88 percent was utilized for direct human consumption (FAO, 2018).

Overfishing our oceans. Leviathanproject. Online: https://www.leviathanproject.us/food-5

Overfishing is evolving to be a major detriment for our environment. One big issue of overfishing arises with fishing of non-targeted species like sharks, turtles and not commonly well known species. This occurs with the trawl fishing method, where the net is so huge that it touches the floor. There is no way that with this method only the needed fish will be taken out of the water. Using this cruel method everything will be fished out within meters and the aqua-eco-system will be destroyed by the net and the huge amount of sea life taken out at one time (OECD, 2008).

Bycatch of non-targeted species, blogs@NTU, 2014.  Online: https://blogs.ntu.edu.sg/hp331-2014-60/?p=223

Additionally other reasons are the poisonous fishing particles arising from the countless fish-farms. Although this is a way of sustainable fishing there is a negative side that comes with this method. Chemicals and antibiotics are used to gain as much fish as possible and to keep them “healthy”. This is where the particles come into the aqua life and destroy the living space of millions and millions of fishes and plants living next to the fish farms. Nevertheless the waste thrown back in the ocean including fishing net, plastic, and general waste completes the hazards of ruining our aqua-eco-system (OECD 2018).

Modern Farming, 2013. Online: https://modernfarmer.com/2013/11/u-s-farming-fish-ever-nowhere-near-china/
Plastic Pollution in the South Pacific – new study into plastic found in commonly eaten fish, Alice Forrest, 2018. Online: https://www.diveplanit.com/marine-environment/plastic-pollution-in-the-south-pacific/

However there is also a meteorological aspect which is growing to be a bigger problem. Every few years the pattern of air circulation of the equatorial Pacific changes in a way that affects oceanic upwelling (a current of cold, nutrient-rich water rising to the surface). This weather condition is known as El Niño and said to happen more and more as a result of the climate change. Basically during El Ninõ, upwelling brings up warm water instead of cold water with only few nutrients. So the missing nutrients will change the whole eco-system. Because sea life which needs the cold water suddenly cannot live there anymore (Department of Oceanography Texas A&M University, 2018).

What is el Niño?,  Wonderopolis, 2018. Online: https://wonderopolis.org/wonder/what-is-el-nino

Nonetheless there must be a way to change those numbers and find a solution to a sustainable way of fishing. Due to the Food and Agriculture Organization of the United Nations more than 60 percent of our worldwide fishes are on their maximum level of utilization. Salmon, tuna, white fish like pangasius or cod are the world’s favourites to be fished and consumed. This leads to a first suggestion: Try to eat different fish, ask for another similar fish, which might be even local, at the counter from your grocery store. Secondly, only eat fish which comes from a sustainable fishery. In reference to the Aquaculture Stewardship Council, they only certify responsible aquaculture. They allow fisheries to use their logo to move the aquaculture industry toward sustainability. So keep an eye on the logo when you buy fish and ask at your grocery store for certified fish (ASC, 2018).

It is not too late for our marine life to get better – we only need to change our behaviour. If we do so, everyone in the industry might realises that they need to change their methods and ways of fishing to become sustainable. It’s up to us – start with something today!

The World’s fish: growing demand and shrinking supply, Bloomberg. Online: https://www.bloomberg.org/press/infographics/worlds-fish-growing-demand-shrinking-supply/

Sources:

Aquaculture Stewardship Council, 2018. What’s our approach. Online: https://www.asc-aqua.org/what-we-do/our-approach/our-approach/  (20.10.2018) 

Department of Oceanography Texas A&M University, 2018. Peruvian Fisheries and El Niño. Online: https://ocean.tamu.edu/academics/resources/ocean-world/fisheries/peruvian-fisheries-and-el-nino/index.html (23.10.2018)

Food and Agriculture Organization of the United Nations, 2018. The State of world fisheries and aquaculture – meeting the sustainable development goals, Rome: Online: http://www.fao.org/3/i9540en/I9540EN.pdf (13.10.2018)

OECD, 2008. Umweltausblick bis 2030, S. 328

OECD/FAO (2018), OECD-FAO Agricultural Outlook 2018-2027, OECD Publishing, Paris/Food and Agriculture Organization of the United Nations, Rome. Online: https://doi.org/10.1787/agr_outlook-2018-en (20.10.2018)