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2.5 Measurement Programs in Urban Environments
The meteorological elements to be measured, in order of priority, are:
• Air temperature
• Surface temperature (natural, artificial)
• Soil temperature (optionally)
• Air humidity
• Wind speed and direction, mean wind profile
• Precipitation
• Radiation, incoming fluxes, outgoing and net fluxes, sunshine duration
• Visibility, meteorological optical range (MOR)
• Evaporation (optionally)
• Soil moisture (optionally)
• Atmospheric pressure (if there is no synoptic station in the vicinity)
• Cloud cover
• Present weather.
Operational measurement uncertainty requirements and instrument performance
for standard near surface meteorological measurements are summarized in WMO
Guidance, 2008. Among the technical parameters, it is highly advisable to study the
accuracy requirements for the following parameters before planning a new meteorological site: range, reported resolution, mode of measurement/observation,
required measurement uncertainty, sensor time constant, output averaging time, and
achievable measurement uncertainty. In the case of meteorological elements, the
technical requirements recommended for urban climate meteorological observations
are listed in Table 2.2. In any case, a description of measurement techniques, sensors characteristics, sampling procedures, calibration, and maintenance requirements are published in the user’s guide or manual of each sensor to be set up. Figure
2.10 depicts a well-equipped urban meteorological and air quality station.
2.6 Site Description for METADATA
Station metadata should contain the following aspects of instrument exposure:
(a) height of the instruments above the surface,
(b) type of sheltering and degree of ventilation for temperature and humidity,
(c) degree of interference from other instruments or objects (masts, ventilators),
(d) microscale and toposcale surroundings of the instrument, in particular
(i) the state of the enclosure’s surface, influencing temperature and
humidity,
(ii) nearby major obstacles (buildings, fences, trees) and their size,
(iii) the degree of horizon obstruction for radiation observations,
2 Urban Heat Island Gold Standard and Urban Heat Island Atlas
2.5 Measurement Programs in Urban Environments
The meteorological elements to be measured, in order of priority, are:
• Air temperature
• Surface temperature (natural, artificial)
• Soil temperature (optionally)
• Air humidity
• Wind speed and direction, mean wind profile
• Precipitation
• Radiation, incoming fluxes, outgoing and net fluxes, sunshine duration
• Visibility, meteorological optical range (MOR)
• Evaporation (optionally)
• Soil moisture (optionally)
• Atmospheric pressure (if there is no synoptic station in the vicinity)
• Cloud cover
• Present weather.
Operational measurement uncertainty requirements and instrument performance
for standard near surface meteorological measurements are summarized in WMO
Guidance, 2008. Among the technical parameters, it is highly advisable to study the
accuracy requirements for the following parameters before planning a new meteorological site: range, reported resolution, mode of measurement/observation,
required measurement uncertainty, sensor time constant, output averaging time, and
achievable measurement uncertainty. In the case of meteorological elements, the
technical requirements recommended for urban climate meteorological observations
are listed in Table 2.2. In any case, a description of measurement techniques, sensors characteristics, sampling procedures, calibration, and maintenance requirements are published in the user’s guide or manual of each sensor to be set up. Figure
2.10 depicts a well-equipped urban meteorological and air quality station.
2.6 Site Description for METADATA
Station metadata should contain the following aspects of instrument exposure:
(a) height of the instruments above the surface,
(b) type of sheltering and degree of ventilation for temperature and humidity,
(c) degree of interference from other instruments or objects (masts, ventilators),
(d) microscale and toposcale surroundings of the instrument, in particular
(i) the state of the enclosure’s surface, influencing temperature and
humidity,
(ii) nearby major obstacles (buildings, fences, trees) and their size,
(iii) the degree of horizon obstruction for radiation observations,
2 Urban Heat Island Gold Standard and Urban Heat Island Atlas