Urban green infrastructure provides important regulating ecosystem services, such as temperature andflood regulation, and thus, has the potential to increase the resilience of African cities to climate change.Differing characteristics of urban areas can be conceptualised and subsequently mapped through the ideaof urban morphology types (UMTs) – classifications which combine facets of urban form and function.When mapped, UMT units provide biophysically relevant meso-scale geographical zones which can beused as the basis for understanding climate-related impacts and adaptations. For example, they supportthe assessment of urban temperature patterns and the temperature regulation services provided by urbangreen structures. UMTs have been used for assessing regulating ecosystem services in European citiesbut little similar knowledge is available in an African context. This paper outlines the concept of UMTsand how they were applied to two African case study cities: Addis Ababa, Ethiopia and Dar es Salaam,Tanzania. It then presents the data and methods used to understand provision of temperature regulationservices across the two cities.In total, 35 detailed UMT classes were identified for Addis Ababa and 43 for Dar es Salaam. Modelledland surface temperature profiles for each of these UMTs are presented. The results demonstrate thaturban morphological characteristics of UMTs, such as land surface cover proportions and associatedbuilt mass, have a much larger potential to alter neighbourhood level surface temperatures compared toprojected climate changes. Land surface cover differences drive land surface temperature ranges over 25◦C compared to climate change projections being associated with changes of less than 1.5◦C.Residential UMTs account for the largest surface area of the cities, which are rapidly expanding dueto population increase. Within the Residential UMTs, informal settlements and traditional housing areasare associated with the lowest land surface temperatures in Addis Ababa. These have higher proportionsand better composition of green structures than other residential areas. The results have implicationsfor planning policies in the cities. In Addis Ababa, the current urban renewal strategy to convert highdensity informal unplanned settlements into formal planned housing needs to explicitly account forgreen structure provision to avoid adverse effects on future supply of temperature regulation services.In Dar es Salaam, condominium UMTs have some of the largest proportions of green structures, and thebest provision of temperature regulation services. In this case the challenge will be to maintain these intothe future.

Urban morphological determinants of temperature regulating ecosystem services in two African cities

CAPUANO, PAOLO;
2014-01-01

Abstract

Urban green infrastructure provides important regulating ecosystem services, such as temperature andflood regulation, and thus, has the potential to increase the resilience of African cities to climate change.Differing characteristics of urban areas can be conceptualised and subsequently mapped through the ideaof urban morphology types (UMTs) – classifications which combine facets of urban form and function.When mapped, UMT units provide biophysically relevant meso-scale geographical zones which can beused as the basis for understanding climate-related impacts and adaptations. For example, they supportthe assessment of urban temperature patterns and the temperature regulation services provided by urbangreen structures. UMTs have been used for assessing regulating ecosystem services in European citiesbut little similar knowledge is available in an African context. This paper outlines the concept of UMTsand how they were applied to two African case study cities: Addis Ababa, Ethiopia and Dar es Salaam,Tanzania. It then presents the data and methods used to understand provision of temperature regulationservices across the two cities.In total, 35 detailed UMT classes were identified for Addis Ababa and 43 for Dar es Salaam. Modelledland surface temperature profiles for each of these UMTs are presented. The results demonstrate thaturban morphological characteristics of UMTs, such as land surface cover proportions and associatedbuilt mass, have a much larger potential to alter neighbourhood level surface temperatures compared toprojected climate changes. Land surface cover differences drive land surface temperature ranges over 25◦C compared to climate change projections being associated with changes of less than 1.5◦C.Residential UMTs account for the largest surface area of the cities, which are rapidly expanding dueto population increase. Within the Residential UMTs, informal settlements and traditional housing areasare associated with the lowest land surface temperatures in Addis Ababa. These have higher proportionsand better composition of green structures than other residential areas. The results have implicationsfor planning policies in the cities. In Addis Ababa, the current urban renewal strategy to convert highdensity informal unplanned settlements into formal planned housing needs to explicitly account forgreen structure provision to avoid adverse effects on future supply of temperature regulation services.In Dar es Salaam, condominium UMTs have some of the largest proportions of green structures, and thebest provision of temperature regulation services. In this case the challenge will be to maintain these intothe future.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11386/4362053
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 52
  • ???jsp.display-item.citation.isi??? 46
social impact