CityDashboard: London (via), by the CASA research lab at University College London.
There’s a fuller list of contributors and sources on the about page, along with this disclaimer:
CityDashboard is an early prototype and should be considered to be “alpha quality” - expect data feeds to break regularly. Please do not rely on information display in CityDashboard, as it may be erroneous. For example, if the CASA Geiger counter is showing a high reading, please do not panic! Somebody in the office might just have placed some Brazil nuts or another calibration source in front of the detector.