iSPEX-EU campaign:
General information
and instruction guide
Thank you for participating in iSPEX-EU, the first Europe-wide citizen campaign of the iSPEX
project! With your help and that of thousands of other people, this will be the largest-ever citizen
campaign for air pollution.
Campaign details:
•
1 September – 15 October 2015
•
More than 10 major cities in Europe
•
Free iSPEX add-on and app
•
Supported phones: iPhone 4, 4S, 5, 5S
Performing iSPEX measurements
Measurement instructions
All iSPEX measurements are done on cloud-free days
and in daytime. Before you start, make sure you have the
iSPEX add-on and your iPhone - equipped with the iSPEX
app - at hand. To perform an iSPEX measurement, go
outdoors and proceed as follows:
1
Find an open space such as a square, park, or similar
location where there are no objects – e.g. buildings,
trees or otherwise – obstructing your view on the sky.
2
Place the add-on onto your phone, in front of the
main camera. Start the app.
3
Make sure the sun is behind you. Hold your iPhone
with iSPEX in front of you, with your arm fully
extended and in-line with your shadow. The iPhone
should be held vertically, such that you can see the
screen and iSPEX points at the horizon. Click ‘Proceed’
to start.
4
Slowly move your arm upwards to scan the sky,
until your arm is in vertical position.
5
Repeat this last step to take a second measurement.
This second measurement is needed for a
consistency check.
6
Your preliminary result, a color-coded
representation of your sky condition based upon your
measurements, is now shown.
7
Press ‘Share’ to upload your measurements to the
iSPEX database. Note: this may take few minutes
depending upon your Internet connection (Wifi
or 3/4G). No connection available? Keep the app
activated and get to a location with connection within
10 minutes to submit your measurements.
8
Once your measurement is submitted, you will be
shown a map with all preliminary iSPEX measurement
results. You can also view this map on
www.ispex-eu.org.
Note: The polarizer that comes with the iSPEX add-on is not needed to take an
iSPEX measurement
Measurement location
Measurement position
Scan procedure
Map with SPEX measurements over Europe
Frequently asked questions and answers
How do I join the campaign and where can I obtain the iSPEX add-on?
Visit the iSPEX-EU website to join the campaign and obtain the add-on.
Where can I obtain the iSPEX app?
The iSPEX app is available for download in the App Store.
What are these so-called aerosols and where do they come from?
Aerosols are tiny solid particles and liquid droplets drifting in our atmosphere. Examples of aerosols are soot,
sea salt, mineral dust – tiny sand particles –, and volcanic ash.
Where do these aerosols come from?
Most of these aerosols – about 90 percent – are of natural origin. Typical sources are sea-spray, volcanic
eruptions, forest fires, and sand storms. The remaining 10 percent of aerosols are anthropogenic, or
human-made, and have a wide variety of origins. Anthropogenic aerosol sources include traffic, industry,
biomass burning, and deforestation.
How tiny are these aerosols that we measure with iSPEX?
Aerosols typically range in size from a few nanometers – less than the size of the smallest viruses – to several
tens of micrometers – the diameter of a thin human hair –.
Why do scientists need to know about aerosols? What does iSPEX want to achieve?
Aerosols are an important part of air pollution. To assess the impacts of aerosols on health, climate, and air
traffic, the properties of aerosols – their type, size, and origin, dynamics and behaviour in the atmosphere –
must be measured in fine detail. With iSPEX you can turn your smartphone into an optical sensor to measure
these aerosol properties, at technically any location and any daytime hour. iSPEX-EU aims to form a network
of thousands of people that perform iSPEX measurements, a network that can provide aerosol information
at locations and times that are not covered by current professional monitoring efforts. So, by joining iSPEXEU you can contribute to aerosol science!
How does iSPEX work?
Aerosols interact with sunlight – they scatter and absorb sunlight, and they change its polarization
(a property of light). With iSPEX you measure both the sunlight intensity and polarization. This means that an
iSPEX measurement contains information on the amount and on the type and size of aerosol(s) in the
atmosphere. On a very sunny day with a perfect blue sky without any clouds or aerosols the sunlight that you
can observe at the Earth’s surface is at its most intense and it is fully un-polarized. In contrast, on a very hazy
day with a large amount of aerosols the sunlight is far less intense and far more polarized.
What do I do with the polarizer that comes with the iSPEX add-on?
The polarizer is meant to be played with and it shows how a polarizer interacts with sunlight. To do so, hold
it in front of iSPEX and turn it around and see how this changes the live spectrum in the app. The polarizer is
not needed to perform an iSPEX measurement.
My iSPEX app doesn’t work. How can I solve this?
Please visit the iSPEX-EU website when you encounter technical issues with the iSPEX app and get the
support needed.
After taking a measurement with iSPEX I am asked to fill out my name. Is this needed?
No, providing your name is optional. If you do provide your name, it will be shown on the live map
accompanying your measurement.
What does my color-code representation of the sky condition mean?
Dark blue means your measurements indicate that your sky is very clear with a minimal amount of aerosols.
Light blue indicates a clear sky with a small amount of aerosols, light brown a slightly hazy sky with a
moderate amount of aerosols, and dark brown a very hazy sky with a big amount of aerosols.
What happens with my iSPEX measurement after I have shared it?
The preliminary result – the color-coded representation of your sky condition based upon your iSPEX
measurements – will appear on the live map in the app and on the iSPEX-EU website. After the campaign,
all iSPEX measurements will be analysed and processed carefully to obtain maps of iSPEX based aerosol
information over Europe. This step is required to filter out erroneous measurements – pictures that
contained buildings or small clouds amongst others and other small measurement mistakes – and obtain the
most accurate result. The final maps of iSPEX based aerosol information will be published on the iSPEX-EU website.
Where can I find more information?
Please visit the iSPEX-EU website to find out more on iSPEX and this campaign, and for the full list of
frequently asked questions and their answers.
Visit www.ispex-eu.org for more information and follow us on twitter @ispex_eu
iSPEX-EU is part of LIGHT2015, a project funded under the
European Union’s Horizon 2020 research and innovation
programme under grant agreement No 644964.
International
Year of Light
2015