Annotations to the interactive data analysis
"Average value" in the table indicates that the value of each measured variable was averaged over the period under consideration, i. e. one day, the last 31 days or the last 12 months.
"Current value" gives the average of the last 30 minutes.
Maximum and minimum values also relate to the period under consideration, i. e. that the maximum and minimum value (as a 30-minute average) of the day, the month or the year are given. In the case of average monthly values, the table also gives the maximum and minimum average value of a day; in the case of average annual values, the maximum and minimum average value of a month.
Any given number of measured variables can be depicted in the diagrams - all in one diagram (mind different measurement ranges!) or in separate diagrams. There is also the option of depicting maximum values instead of average values.
Climate dataPerceived temperature (in the sun):
Results from an empirically developed formula on the basis of the measured values for air temperature, wind speed and global radiation. What is not taken into account is the individual's clothing and degree of motion.
Perceived temperature (in the shade):
Results from an empirically developed formula on the basis of the measured values for air temperature and wind speed. What is not taken into account is the individual's clothing and degree of motion.
Wind chill:
The wind chill effect describes the cooling of our body in strong wind, especially when temperature is low.
Precipitation:
Is added to 30-minute values, daily values, monthly values or annual values. No averages are made. The amounts are given in litres per square metre (l/m²). The intensity of precipitation is not analysed or only in relatively long 30-minute intervals.
Global radiation:
Covers the sum of direct and diffuse solar radiation. The spectral range covers short wave radiation (0.3-3 µm).
Net total radiation:
Results from the difference from short wave global radiation and long wave atmospheric counter radiation on the one hand and short wave reflected radiation and long wave temperature radiation of the earth on the other hand (measurement range: 0.3 - >30 µm).
UVA radiation:
Long wave part of UV radiation (ultraviolet radiation, below the visible spectral range < 0.36 µm) in a spectral range > 0.313 µm. It plays an important role in strengthening our immune system and is responsible for the tanning of the skin.
UVB radiation:
Short wave part of UV radiation (< 0.313 µm). UVB radiation is dangerous because it can cause irreversible skin damage.
UV index:
Results from the measured amount of UVA and UVB radiation and includes the spectral sensitivity of the human skin. The UV index varies between 0 and above 8 in our region. Forecasts and explanations can be obtained from the Federal Office for Radiation Protection (Bundesamt für Strahlenschutz) (available in German and in English). Recommendations for the correct sun-protection factor and the time you can spend in the sun depending on your individual skin type can be found here (available in German and in English).
Air dataData representation:
The pollutant concentration values are indicated as mass concentrations, i. e. pollutant mass per cubic metre of air. The masses generally are in the microgram range (µg = 10-6 g), carbon monoxide masses in the milligram range (mg = 10-3 g). The air pollution index (API) is a relative value and indicates no concentration. This is why it has no unit. For further information on each pollutant and on the evaluation of their concentration in the air, please read the principles of air pollution control.
Ozone potential:
The ozone potential indicates the ozone concentration value which may currently be reached if all nitrogen dioxide is chemically converted into ozone. This is why the ozone potential is an indicator for ozone values which can be reached in surrounding regions with a comparable nitrogen oxide concentration. In order to calculate the ozone potential, the volumetric contents of the two components (NO2, O3) are added up and represented as ozone mass concentration. For further information on ozone creation in urban centres, please click here.
API (summer/winter):
The air pollution index (API) is a summary representation of the air quality, divided into summer and winter half year. The more relevant components are always taken into account. The single components are divided by their individual evaluation value, these quotients are added up and the result is divided by the number of components. The result can be evaluated by the example of Stuttgart's air quality targets. An API of 1.0 indicates that all components taken into account reach their evaluation value on average. An API of 0.5 indicates, that the evaluation values are reached at 50 % on average.
Airborne particles:
What is most harmful to our health is very small particulate matter. This is why our measuring stations have been collecting since 2000/2001 what is called the PM10 value, which only considers particles with an aerodynamic diameter smaller that 10 micrometres (µm). The results are therefore unsuitable for the comparison with older airborne particle values.
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| © City of Stuttgart, Office for Environmental Protection, Section of Urban Climatology |
