E2
“Step 2: Define the thermal source area. The thermal source area for a temperature
measurement is the total surface area «seen» by the sensor […].” (Stewart and
Oke, 2012, p. 1890) “Sources will include upwind buildings, the walls and floor
of an upwind street, and perhaps a branching network of more distant street canyons” (p. 1890).
“Quantifying the surface properties for field sites and source areas located on or
near the border of two (or more) zones is problematic. If the location of the sensor
can be moved, it should be placed where it samples from a single LCZ. […]. If the
location of the sensor cannot be moved, temperature data retrieved from that site
should be stratified first according to wind direction, then to LCZ. […] A site with
a split classification is less ideal for heat island studies because changes in airflow
and stability conditions interfere confuse the relation between surface form/cover
and air temperature. It is recommended that transitional areas be avoided when
siting meteorological instruments” (Stewart and Oke, 2012, p. 1891).
“Step 3: Select the local climate zone. Metadata collected in Step 1 should lead
users to the best, not necessarily exact, match of their field sites with LCZ classes.
Metadata are unlikely to match perfectly with the surface property values of one
LCZ class. If the measured or estimated values align poorly with those in the
LCZ datasheets, the process of selecting a best-fit class becomes one of interpolation rather than straight matching. Users should first look to the surface cover
fractions of the site to guide this process. If a suitable match still cannot be found,
users should acknowledge this fact and highlight the main difference(s) between
their site and its nearest equivalent LCZ” (Stewart and Oke, 2012, p. 1891).
Stewart and Oke (2012) note that “updating LCZ designations is crucial for all
sites, particularly those used in long-term temperature studies” (p. 1893). They add
that “sites located on the edges of cities where urban growth and environmental
change are rapid, or in the cores of cities where land redevelopment and large-scale
greening projects are taking place, should be surveyed and classified annually. For
sites used in mobile or short-term stationary surveys, the frequency of updates is
dictated largely by day-to-day variations in weather and soil moisture […]”
(p. 1893).
Reference
Stewart, I. D., & Oke, T. (2012). “Local Climate Zones” for urban temperature studies. Bulletin of
the American Meteorological Society, 93, 1879–1900.
“Step 2: Define the thermal source area. The thermal source area for a temperature
measurement is the total surface area «seen» by the sensor […].” (Stewart and
Oke, 2012, p. 1890) “Sources will include upwind buildings, the walls and floor
of an upwind street, and perhaps a branching network of more distant street canyons” (p. 1890).
“Quantifying the surface properties for field sites and source areas located on or
near the border of two (or more) zones is problematic. If the location of the sensor
can be moved, it should be placed where it samples from a single LCZ. […]. If the
location of the sensor cannot be moved, temperature data retrieved from that site
should be stratified first according to wind direction, then to LCZ. […] A site with
a split classification is less ideal for heat island studies because changes in airflow
and stability conditions interfere confuse the relation between surface form/cover
and air temperature. It is recommended that transitional areas be avoided when
siting meteorological instruments” (Stewart and Oke, 2012, p. 1891).
“Step 3: Select the local climate zone. Metadata collected in Step 1 should lead
users to the best, not necessarily exact, match of their field sites with LCZ classes.
Metadata are unlikely to match perfectly with the surface property values of one
LCZ class. If the measured or estimated values align poorly with those in the
LCZ datasheets, the process of selecting a best-fit class becomes one of interpolation rather than straight matching. Users should first look to the surface cover
fractions of the site to guide this process. If a suitable match still cannot be found,
users should acknowledge this fact and highlight the main difference(s) between
their site and its nearest equivalent LCZ” (Stewart and Oke, 2012, p. 1891).
Stewart and Oke (2012) note that “updating LCZ designations is crucial for all
sites, particularly those used in long-term temperature studies” (p. 1893). They add
that “sites located on the edges of cities where urban growth and environmental
change are rapid, or in the cores of cities where land redevelopment and large-scale
greening projects are taking place, should be surveyed and classified annually. For
sites used in mobile or short-term stationary surveys, the frequency of updates is
dictated largely by day-to-day variations in weather and soil moisture […]”
(p. 1893).
Reference
Stewart, I. D., & Oke, T. (2012). “Local Climate Zones” for urban temperature studies. Bulletin of
the American Meteorological Society, 93, 1879–1900.
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