THE TEMPORAL DIMENSION
The article concerns about temporal(time)dimension of urban design under the circumstances of impacts of time on places, changing occasions in cycles by progressive or irreversible ways.
According to Kevin Lynch, affect of time on space can be experienced by two ways: First one is; rhytmic repetition which refers to breathing/sleeping/walking/cycles of sun/moon/the seasons...Second one is; progressive and irreversible change which refers to growth and decay time and space are related to each other.
Three key aspects of temporal dimension of urban design are;
Time cycles and management of activities in space.
Continuity and stability.
Changing urban design projects and policies.
Time Cycles: Main time cycles are based on natural cycles(our bodily cycles). The use of urban space differs according to these cycles of day,night,seasons. At different times of the day,night, urban environment is perceived and used differently and also users differ according to changing time cycle.
Urban designer have to be aware of these cycles to supply usable,effective, lively urban environment. Otherwise the urban space starts to be abondaned. The main point is to compose 24 hours sociable environments.
The Time Management of Public Space: Mixed use creates more life and activity in alocation. So, different land uses can be different preferences for different time cycles. Place design can be differ according to users such as retired people,working people.Their aim of the use of a place differs according to their life style.
Urban designers need to understand activity patterns, how to encourage activities through different time periods and how to achieve synergies from activities happening in the space and time.
Street design can change according to time. As people visit an area to see what is going on, urban viality is further stimulate and the public realm becomes animated by having more people on the streets and in cafes.
Safety, viality, attractive activities, crowdness,congestion are the important points in deigning public realm and design for a broad range of social group is essential for a community. In city centers some time periods are dead. To prevent this, the concept of 24 hour lively design can be applied.
Under the term of “march of time” article mentioned about that time pass causes technological, social and cultural changes. These changes and spirit of time affect urban environment physically. And also, natural processes, forces, wars, revolutions cause irreversible change on urban spaces. For instance, there are some basic time period that are affcted by these changes such as in history, at 1940s and 50s after II post warr there was buldozer movement on slum areas under the name of slum clearence, when we came 1960s and 70s sustainable design and beginning of conservation and soft urban renewal occured. At 1980s conservation of historic environments, buildings started. These are effects of irreversible changes on urban space. Under the topic of conservation Desdall list more common justifications;
Value for aesthetic Value for architectural diversity and contrast.
Value for environmental Value for functional diversity
Resource Value Value for Continuity of cultural memory and heritage
Economic Value Commercial Value
In the process of conservation, conservation policies chage over time. Important point is urban designers need to understant how environments adapt to change in this process. It is importnt to distinguish what is fundamental to the sense of place and should remain, from what is less important and can change. The visual and physical continuity of valued places relates to issue of the obsolescence of buildings and environments.
In historic protection process although there are many types of interventions such as restoration,preservation, refurbishment, conservation etc., it can not prevent the obsolescence. Another essential point of time dimension is to aware of what stays the same and what changes over time. While street and plot patterns changes slowly, buildings and landuses changes rapidly because of the effect of robustness, resillence. These concepts have an fundamental role.
Resillence is the ability to resist change without deformation. It resists physical and structural obsolescence. Robustness is the ability to accomodate chande without significant change in physical form. It resists functional obsolescence.
Under all these interventions fundamental point is management. Decisions have potentially long lasting implications and effects. Furthermore, given the short termism of markets and market behaviour, urban designers must consider long term issues relating to sustainability to create an viable environment and to supply social cultural economical continuity of a community.