Part III. The Climate of Brno
Main aim: What are typical features of spatial and temporal climate variability in Brno?
1. Local geography character
a. Land use distribution
b. Complex relief
2. History of meteorological measurements
a. No typical urban station
b. Compiled series of air temperature and precipitation. Air temperature is rising
continuously (since 1960s) while precipitation demonstrate high inter-annual
variability without any long term trend.
Q1: Is it useful to have a long term measurements?
Q2: What do we need for analysis of urban climate?
3. Meteorological data (dependent, target variables)
a. Standard measurements at professional stations (Met-service)
b. Special-purpose measurements
c. Mobile measurements
d. Measurements from remote sensing systems (satellite imagery)
4. Geographical database (independent, explanatory variables) in the form of 300 x 300 m grid
cells
a. Altitude
b. Density of buildings
c. Density of vegetation
d. Density of roads
e. Sky view factor
Q3: Do they reflect all main factors that control urban climate?
5. Two examples of air temperature variability analysis
a. Land surface temperatures (LSTs) derived from thermal satellite images
i. We quantified to what extent different land use categories
increase/decrease LSTs
ii. “Hot-spots” occur in typical parts of the city
iii. Amount of vegetation (in the form of NDVI) explains more than 2/3 of LST
variability
Q4: What parts of the city are most susceptible to higher temperatures?
b. Nocturnal air temperature field analyzed from mobile measurements
i. The same explanatory variables, but used for air temperature analysis
ii. Design of traverses through the city
iii. Amount of air temperature variability explained – the best result for density
of vegetation and density of buildings. Weak influence of altitude.
iv. Typical air-temperature spatial distribution – Urban heat island (UHI)
Q5: Why it is important to study temperatures at night?
Q6: Compare positive/negative features of the two methods?