Modern high-resolution measurement network
The first step of developing a city climate system is the installation of a meteorological sensor network (air temperature, relative humidity, precipitation, etc.) within the city. meteoblue has developed several tools to assess the best sensor locations within a city and in the surrounding areas. Once the sensors are installed, meteorological data can be received real-time via API, web, FTP or mobile app. Meteorological data are quality controlled and corrected for e.g. radiation measurement errors. The sensor network is key to provide reliable information for managing a city’s climate change mitigation measures.
Mapping of local climate zones for any city of the world
meteoblue provides local climate zone maps for any city in the world. A climate zone map is generated from satellite images with a horizontal resolution of 10m. Local climate zone information is the basis for sensor placement, for statistical analysis, and for model validation and improvement.
Small-scale modelling of meteorological variables
meteoblue calculates small-scale meteorological variable fields for cities with a horizontal resolution of 10m for each measurement time step of 15 minutes. The meteoblue city climate models interpolate locations in between sensor locations with special techniques accounting for data from satellites as well as digital surface and elevation models. Air temperature, precipitation, wind speed and wind direction are assessed for any location in the city, bringing weather information to each doorstep. Based on the small-scale air temperature field, urban heat islands are detected as well as cold inflows. In addition, flood and hail warnings for the city can be created on the base of high resolution precipitation data. Air pollution is assessed automatically by combining local air pollution sources with a three-dimensional wind field calculation.
High computational power from the cluster
meteoblue runs city climate models on a very fine horizontal resolution down to 0.5 m (see sky view factor on the right). The sky view factor expresses the proportion of sky visible from a point on a surface. Street canyons or areas covered by trees have a low sky view factor in contrast to the high sky view factor of open places and building rooftops. The model calculations require substantial computational power. Historical data, a nowcast, a seven-day forecast as well as climate projections are all calculated for any point in the city and stored on the meteoblue cluster.
High accuracy of city-climate models
The meteoblue city climate models perform better than 1°C for the spatial interpolation technique, with a decreasing error when using more stations. We can calculate the number of stations needed to achieve the desired accuracy of modelled data. Based on our existing verifications, for our 24h forecast an accuracy of 1.2 °C for air temperature can be expected.