Here is a draft of my contribution about Athens, which is conceived as a paragraph for the "Urban Heat Island" article. I am still working around it, some term may be improved. The title will be "The Case of Athens, Greece".
"The city of Athens is characterized by a strong heat island effect, mainly caused by the accelerated industrialization and urbanization during recent years." (Giannakopoulos et al. 2010:746). [1] The urban heat island of Athens is studied within the framework of the campaign "Thermopolis 2009" by the Democritus University of Thrace with the support of ESA [2] and several other studies. Satellite measurements of surface temperature revealed that "In the case of Athens [...], mixed urban areas are hot spots and appear to be 3.5–4°C warmer than the surrounding rural areas, during daytime, a fact that can be attributed to intense human and industrial activities". [3] Kassomenos and Katsoulis (2006) detect strong urban heat island affecting Athens for 1/3 of the days, switching on in the afternoon and being stronger with low humidity and clear sky conditions. [4] Santamouris et al. (2001) by the use of 30 meteorological stations and specific measurements detect levels of urban heat island as strong as exceeding 10°C in extreme cases in central Athens during daytime and up to 5°C during the night. [5] A daytime negative urban heat island may be detected in Athens under some synoptic conditions. [6] [7] [8] The urban heat island effect in Athens is not homogeneous inside the city: it is more intense in some western parts, and less intense in green areas; it is more intense in open-surrounded positions in presence of asphalt and intense traffic circulation. [9] The urban heat island of Athens is also variable according to the season, and winter is the period of less intense effect. [10] According to Livada et al. (2002) some green areas that are protected by greenery such as the National Gardens inside metropolitan Athens are less or not affected by the UHI. [11] The urban heat islands have implications also for climate change analysis. A early detection of Athens urban heat island effect over the temperatures measured by the NOA meteorological station at Thiseio was reported by Katsoulis (1987:75-76): "[...] the differences in the maximum and minimum temperature trends may be interpreted as a long-term variation due to che city's growth and the result of increasing urban temperature due to human causes". [12] An effect of +1/+2°C on its summertime maximum temperatures due to urban heat island is reported by different studies. [13] [14] [15] The warming observed in annual and summer air temperature times-series of the National Observatory of Athens weather station at Thiseio between 1970 till mid 1990s compared to reference non-urban stations "[...] must be attributed to the urban effect of Athens city as has been demonstrated by many scientists" (Repapis et al. 2007:110). [16] The effect of the urban heat island on the maximum temperatures measured by the meteorological station of the National Observatory of Athens at Thiseio is variable across the year: it amounts about +2°C in spring and summer, less in fall, while no clear urbanization effect is detected in winter. [17]
Here is a draft of my contribution about Athens, which is conceived as a paragraph for the "Urban Heat Island" article. I am still working around it, some term may be improved. The title will be "The Case of Athens, Greece".
"The city of Athens is characterized by a strong heat island effect, mainly caused by the accelerated industrialization and urbanization during recent years." (Giannakopoulos et al. 2010:746). [1] The urban heat island of Athens is studied within the framework of the campaign "Thermopolis 2009" by the Democritus University of Thrace with the support of ESA [2] and several other studies. Satellite measurements of surface temperature revealed that "In the case of Athens [...], mixed urban areas are hot spots and appear to be 3.5–4°C warmer than the surrounding rural areas, during daytime, a fact that can be attributed to intense human and industrial activities". [3] Kassomenos and Katsoulis (2006) detect strong urban heat island affecting Athens for 1/3 of the days, switching on in the afternoon and being stronger with low humidity and clear sky conditions. [4] Santamouris et al. (2001) by the use of 30 meteorological stations and specific measurements detect levels of urban heat island as strong as exceeding 10°C in extreme cases in central Athens during daytime and up to 5°C during the night. [5] A daytime negative urban heat island may be detected in Athens under some synoptic conditions. [6] [7] [8] The urban heat island effect in Athens is not homogeneous inside the city: it is more intense in some western parts, and less intense in green areas; it is more intense in open-surrounded positions in presence of asphalt and intense traffic circulation. [9] The urban heat island of Athens is also variable according to the season, and winter is the period of less intense effect. [10] According to Livada et al. (2002) some green areas that are protected by greenery such as the National Gardens inside metropolitan Athens are less or not affected by the UHI. [11] The urban heat islands have implications also for climate change analysis. A early detection of Athens urban heat island effect over the temperatures measured by the NOA meteorological station at Thiseio was reported by Katsoulis (1987:75-76): "[...] the differences in the maximum and minimum temperature trends may be interpreted as a long-term variation due to che city's growth and the result of increasing urban temperature due to human causes". [12] An effect of +1/+2°C on its summertime maximum temperatures due to urban heat island is reported by different studies. [13] [14] [15] The warming observed in annual and summer air temperature times-series of the National Observatory of Athens weather station at Thiseio between 1970 till mid 1990s compared to reference non-urban stations "[...] must be attributed to the urban effect of Athens city as has been demonstrated by many scientists" (Repapis et al. 2007:110). [16] The effect of the urban heat island on the maximum temperatures measured by the meteorological station of the National Observatory of Athens at Thiseio is variable across the year: it amounts about +2°C in spring and summer, less in fall, while no clear urbanization effect is detected in winter. [17]