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X. Adaptation and mitigation
URBAN CLIMATOLOGY
Summary of expected climate changes
in Central Europe
• Rising temperatures and higher intensity of Urban Heat Island
• Higher frequency and longer duration of heat waves
• Changes in precipitation distribution during a year
• More frequent occurrence of high precipitation totals of short
duration, higher probability of local floods
• Higher frequency of drought periods without precipitation
Survive New York’s Heat Waves
Stay cool during your trip to New York
(http://www.frenzytours.com)
Adaptation and mitigation in urban climatology
Two main goals :
1) To deal with negative effects of urban climate as a type of local
climate (higher extremity, UHI, heat load, etc.)
2) To deal with negative impacts of recent climate change in cities
• In cities climate change is strongly intertwined with other socioeconomic
changes: demographic trends, higher proportion of older
people, urbanization, competing demand for water, etc.
• These socio-economic changes increase the vulnerability of
people, property and ecosystems under current climate conditions
as long as no adaptation measures are taken.
• Negative impacts of climate change in cities require various
actions, strategies, technologies that help inhabitants to adapt or
mitigate.
Adaptation and mitigation - terminology
Adaptation to climate change is the adjustment in urban areas in response to actual
or expected climatic stimuli or their effects. It moderates harm or exploits beneficial
opportunities of climate change.
Adaptivecapacity is the ability of urban areas to adjust to climate change to
moderate potential damages, to take advantage of opportunities or to cope with the
consequences.
Vulnerability is the degree to which a system is susceptible to, and unable to cope
with, adverse effects of climate change, including climate variability and extremes.
Mitigation of climate change is an anthropogenic intervention to reduce the
anthropogenic forcing of the climate system. It includes strategies to reduce
greenhouse gas sources and emissions and enhancing greenhouse gas sinks.
Resilience is the ability of a social or ecological system to absorb disturbances while
retaining the same basic structure and ways of functioning, the capacity for selforganization
and the capacity to adapt to stress and change.
Goal 1: Causes of urban warming and mitigation strategies (Grimmond, 2007)
Adaptation strategies (approaches)
1. 'Grey' infrastructure approaches - physical interventions or construction
measures and using engineering services to make buildings and infrastructure
essential for the social and economic well-being of society more capable of
withstanding extreme events.
2. 'Green' infrastructure approaches - contribute to the increase of ecosystems
resilience and can halt biodiversity loss, degradation of ecosystem and restore
water cycles. At the same time, green infrastructure uses the functions and
services provided by the ecosystems to achieve a more cost effectiveand
sometimes more feasible adaptation solution than grey infrastructure.
3. 'Soft' approaches - include policies, plans, programs, procedures, information
dissemination and economic incentives to reduce vulnerability, encourage
adaptive behavior. They are related to behavioral changes, emergency systems
and the adequate provision of information to vulnerable groups.
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Adaptation strategies (approaches)
Overview on grey, green and soft adaptation measures to heatwaves
(Urban adaptation to climate change in Europe, EEA Report 2012)
Resilient cities
“green” city “blue” city “white” city
Adaptation strategies (approaches)
Further possibilities:
• Energy saving and passive houses
• Warning systems and disaster risk management programs
• Urban adaptation relies on action beyond cities' borders (flooding
due to inappropriate land use and flood management in upstream
regions) and incudes reducing cities' dependency on external
services
Low share of green and blue urban areas and high population densities
can contribute to the urban heat island effect in cities
(Urban adaptation to climate change in Europe, EEA Report 2012)
Percentage of green and blue urban areas — share of cities per class
per country
(Urban adaptation to climate change in Europe, EEA Report 2012)
Vulnerable people — the elderly are considered to be a group more
sensitive to various climatic stress factors than people of a working age
(Urban adaptation to climate change in Europe, EEA Report 2012)
Percentage of population aged ≥ 65 — share of cities per class
per country
(Urban adaptation to climate change in Europe, EEA Report 2012)
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Urban climate analysis map for the city of Arnhem, the Netherlands
(Urban adaptation to climate change in Europe, EEA Report 2012)
Climate planning strategy, Stuttgart (Germany)
(Urban adaptation to climate change in Europe, EEA Report 2012)
An excellent example of urban heat island management. The city of Stuttgart has been
designed to not only respect and protect nature, but to exploit how natural wind patterns
and dense vegetation can actively help the city to reduce its problems of overheating and air
pollution.
http://www.stadtklima-stuttgart.de
At night cool air sweeps down
from the surrounding hills and
runs through a series of
'ventilation-corridors' which
have been kept open as wide,
tree-flanked arteries within the
city's street infrastructure.
Analog scenarios
Land cover maps of Brno in 1870s, 1940s and at present
• Model simulations with different
land use / land cover parameters
• „what – if“ scenarios
1870s
1940s
2010s
Mills (2006) - the sustainable city is the new urban utopia
Final remarks and questions
1. How to persuade politicians (local authorities) that some
adaptations/mitigations are needed?
2. What is the role of geographers in the adaptation process
of cities to climate change?