Professor Rob MacKenzie, director of Birmingham Institute of Forest Research, Air Quality and Urban Form, gave a presentation on the rôle of trees and the urban forest, while Professor Rohinton Emmanuel, director of The BEAM Research Centre, Glasgow Caledonian University, spoke on heat islands, urban form and the green infrastructure, thermal comfort and energy implications.
Following the seminar, the group was taken on an urban climate walking tour entitled 'Walking Among Giants', organised by Rupert Bentley Walls, formerly senior tree officer for the London Borough of Hackney and now of Barcham Trees. The walk was led by architect Dr Julie Futcher of Urban Generation, a network-based urban regeneration design studio offering architecture, green and blue infrastructure solutions, alongside an urban climate consultancy.
Futcher has a Ph.D. in Integrated Urban Energy Management, and as a qualified architect she has great experience in the urban realm, including the thermal control of external spaces, such as ventilation and solar access to improve building and pedestrian comfort and wellbeing. Her expertise concerns the rôle of urban form as a climate modifier, and she works with the urban climate and building energy management community.
The walk was a tour through the eastern cluster of the City of London, where tall buildings are being built, many of which are unusually shaped. The tour focused on the changing built form of the city and how we use our senses to interpret the landscape. The theme that linked the stopping points along the way was energy, both in its natural expressions - temperature, wind, sunshine - and those of building needs, such as cooling and heating loads, and how these two are interdependently linked at the scale of the city street.
The walk began at Finsbury Square Gardens, situated on the border between the borough of Islington and the City of London, and proceeded to South Place, looking towards Ropemaker Place. From this point, looking west along Chiswell Street, very tall buildings have created a narrow canyon. The party then went to the corner of Wormwood Street and Bishopsgate, where the Heron Tower, rising more than 180m, could be viewed, and then on, past Norman Foster's 'Gherkin', to the corner of St Mary Axe and Leadenhall Street, which is the heart of the City's eastern cluster. With so many tall buildings so close together here, there is a variation of conditions experienced on the ground, depending on wind direction and sun position.
It was then on to Fenchurch Street, where the 'Walkie-Talkie' building at 20 Fenchurch Street was seen and discussed. This was the structure which in September 2013 became notorious when the intensity of the solar energy concentrated and reflected downwards from its curved, south-facing façade on to the pavement and buildings of Eastcheap melted parts of a car and singed the carpet in a barber's. The tour concluded on the Embankment, with The Shard in view. It is 300m tall and its shadow at noon extends more than 350m for half of the year.
Bentley-Walls said the walk highlighted how imperative is the need to ensure that trees and green infrastructure are thought of from the very start and not just as an afterthought within the urban environment: "We could be utilising the natural environment and trees to better effect and use within the capital to help in mitigation measures and to ensure the quality of working and living in our cities does not adversely affect our health and wellbeing. Careful thought on green space, tree species choice and selection can only benefit the quality of our lives within the built landscape, so we can have an effective Urban Forest for future generations."