INKAS A guidance tool to assess the impact of adaptation on urban heat

Transcription

1 INKAS A guidance tool to assess the impact of adaptation on urban heat Meinolf Kossmann and Saskia Buchholz German Meteorological Service (DWD) Climate and Environment Consultancy European Conference on Biodiversity and Climate Change November 2015, Bonn Nature-Based Solutions to Climate Change in Urban Areas and their Rural Surroundings - Linkages between Science, Policy and Practice

2 Outline 1 2 Climate Adaptation in Cities Reasons for Adaptation Deficits Adaptation Measures and Urban Climate Simulations 3 Results Green Roofs 4 INKAS - A guidance tool to assess the impact of adaptation on urban heat 5 Conclusions ECBCC 2015, Bonn Slide 2

3 1 Climate Adaptation in Cities Climate Adaptation is only one Challenge for Cities and Municipalities Infrastructure Decreasing Tax Revenue Demographic Change Energy Transition Urban Climate Studies (Basic Data) Financial and human resources Big Cities Small Cities ECBCC 2015, Bonn Slide 3

4 2 Adaptation Measures and Urban Climate Simulations Adaptation measures against Urban Heat Urban Green Park size and distribution Tree cover Soil moisture Water surfaces Size and distribution Water temperature Settlement types Building height Building surface fraction Impervious surface fraction Building shape Adaptation Measures - Urban Heat Reduction Properties of surfaces and urban fabric Albedo Heat conductivity Green roofs ECBCC 2015, Bonn Slide 4

5 2 Adaptation Measures and Urban Climate Simulations Climate Simulations for Idealized Cities Characteristics of Terraced housing estate in the urban climate model Mean Building height 9 m Surrounding City Buildings Impervious Surface Low Vegetation Bare Soil Park Tree Cover 20% Characteristics of a park area in the urban climate model Impervious Surface Low Vegetation Bare Soil ECBCC 2015, Bonn Slide 5

6 3 Results Example: Increase Fraction of Green Roofs Conventional Roof Green Roof Reflection of solar radiation Heat transfer into the air Heat transfer into building Evaporation Fraction of Green Roofs Settlement Types A Single- and multifamily residential B Village and single family residential C Terraced housing estate D Terrace houses E Terrace houses/high-rise buildings F Tenement block residential G City later mid-19th century H Medieval city I Commercial and industrial ECBCC 2015, Bonn Slide 6

7 3 Results Increase Fraction of Green Roofs TERRACE HOUSES TMAX INDUSTRY TMAX % Proportion of Green Roofs ECBCC 2015, Bonn Slide 7

8 3 Results Increase Fraction of Green Roofs TERRACE HOUSES TMAX INDUSTRY TMAX % Proportion of Green Roofs ECBCC 2015, Bonn Slide 8

9 4 INKAS INformationsportal KlimaAnpassung in Städten Impact Analysis 9 settlement types 4 urban surrounding types 7 adaptation measures ~ 2000 model simulations Area Analysis 9 settlement types ~ 150 model simulations ECBCC 2015, Bonn Slide 9

10 4 INKAS Area Analysis Synopsis of all Model Results Air temperature difference T max 30 Air temperature difference T min 20 ai: impervious surface fraction ab: building surface fraction ap: pervious surface fraction ab Red: threshold exceedance Blue: threshold not exceeded ECBCC 2015, Bonn Slide 10

11 4 INKAS Area Analysis Synopsis of all Model Results ai: impervious surface fraction ab: building surface fraction ap: pervious surface fraction Buchholz, S. und Kossmann, M. (2015) Research note. Visualisation of summer heat intensity for different settlement types and varying surface fraction partitioning. Landscape and Urban Planning 144, 59-64, doi: /j.landurbplan ECBCC 2015, Bonn Slide 11

12 5 Conclusions Important findings from INKAS include Street-level air temperature reductions due to increased albedo (roofs, walls, pavements) are strongest during daytime. Effects of roof level adaptation measures (albedo, vegetation) on street-level air temperatures are smallest for settlements with high buildings and/or small building surface fractions. Small built-up and impervious surface fractions favour low maximum and minimum street-level air temperatures. Exceptions occur for very high building density, where shading effects become more effective. INKAS provides quantitative data for climate resilient urban planning (e.g. impact assessment or cost-benefit analysis of adaptation measures) ECBCC 2015, Bonn Slide 12

13 5 Conclusions Remarks A brochure on INKAS is available for interested users. Feedback on content and usability of INKAS is welcome. INKAS content and functionalities will be extended. ECBCC 2015, Bonn Slide 13

14 Thank you for your attention Contact: Meinolf Kossmann