M. Santamouris, K. Paraponiaris and G. Mihalakakpou

University of Athens, Department of Physics, Division of Applied Physics, Laboratory of
Meteorology, University Campus, Build. PHYS-V, Athens, GR 15784. Greece.

1. Introduction

The city of Athens is characterised by a strong heat island effect, mainly caused by the accelerated industrialisation and urbanisation during recent years. The urban heat island phenomenon has been investigated in 23 experimental stations located in the Greater Athens Area, (GAA). Hourly values of ambient air temperature and relative humidity were recorded at each station. Based on the above mentioned experiment, the influence of various climatic parameters and of the prevailing synoptic conditions on the heat island effect was studied in (Santamouris et al., 1999; Mihalakakou et al., 2002; Mihalakakou et al., 2003; Livada et al., 2002). In Santamouris et al. (2001) it can be seen the impact of the urban climate in the greater Athens area on the energy consumption of urban buildings during summer 1996. Moreover in Hassid et al. (2000) it can be observed the effect of the Athens heat island cooling energy consumption of another reference building in various stations of the western GaA and for the years 1997 and 1998.

Everybody has an impact on Earth, as they consume the products and services of nature. Their ecological impact corresponds to the amount of nature they occupy to keep them going. The ecological footprint is defined as the the land and water area that is required to support indefinitely the material standard of living of a given human population, using prevailing technology, (Rees, 1992). The ecological footprint is a measurement of the ecological sustainability, illustrating the reality of living in a world with finite resources, (Barett and Scott, 2001). It provides a final figure in land areas, (in hectares), which is necessary to support an individual, city, region, country or the entire world population. It provides a visual picture of the Earth’s carrying capacity. For that reason, the ecological footprint has become recently very popular as it can offer a representative idea of the ecological limits, which is one of the main topics of sustainable development. The ecological footprint can be regarded as a potential aggregated indicator for sustainable development. Each year the ecological footprint becomes more refined, portraying a more and more accurate figure of the appropriated land for humanity, (Wackernagel and Rees, 1996; Simmons and Chambers, 1998; Wackernagel et al., 2000).

Calculation of the additional ecological footprint is performed by simulating the additional energy consumption of buildings caused by the heat island effect. Simulations have been performed using experimental data from various urban climatic stations located in the Athens Urban area, for the summer period of the years 1997 and 1998. The ecological footprint of this energy cost is then calculated in the present study using the globally accepted CO2 sequestration pattern.