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1.3.2.1 Data and Methods
Regional climate simulations of the ENSEMBLE RT2B model (for more information see http://ensembles-eu.metoffice.com/) with daily resolution are used as the
data basis for the analysis of climate change in the greater region of Stuttgart for
1960–2100. The RT2B model focuses on the SRES A1B scenario. The regional
climate model REMO (for more information see http://www.remo-rcm.de/) in
hourly resolution and 10 km spatial resolution focusing on SRES A1B and B1 scenario is used to analyze the human thermal comfort conditions.
Therefore, the thermal index Physiologically Equivalent Temperature (PET;
Höppe 1993; Mayer and Höppe 1987; Matzarakis et al. 1999) is calculated with the
help of the micro-climate model RayMan (Matzarakis et al. 2007, 2010). PET is
used to quantify especially the frequency and intensity of heat stress. Thereby,
PET between 18 °C and 23 °C was assessed to be comfortable, while PET above
35 °C (Nastos and Matzarakis 2012) stands for strong heat stress (Matzarakis and
Mayer 1996).
The dataset is used to calculate the number of climatologically event days and
their change until the end of the twenty-first century.
1.3.2.2 Results
Table 1.3 shows the frequency of climatological event days. The frequency of hot
days (Tamax ≥ 30 °C) and summer days (Tamax ≥ 25 °C) will increase to 174 % and
140 % in the period 2021–2050 and 280 % and 157 % until end of the twenty-first
century. On the other hand the number of frost (Tamax ≤ 0 °C) and ice days
(Tamax ≤ 0 °C) per year will decrease to 33 % in the period 2071–2100.
The average annual air temperature might rise by 1.5 °C from 1961–1990 to
2021–2050 and 3.5 °C until the end of the twenty-first century (Table 1.3). Thereby,
the increase in air temperature is strongest during summer and winter and weakest
in spring.
The number of days per year with heat stress (PET > 35 °C) at 14:00 MEZ will
increase by 6 days from 1961 to 1990 to 2021–2050 and by 28 days until the end of
the twenty-first century according to the REMO data A1B scenario. The B1 data
shows no increase until the mid of the twenty-first century, but an increase of 4 %
(16 days) until 2071–2100 (Table 1.2).
In the early morning (6:00 MEZ), the number of days with (extreme) cold stress
will significantly decrease by 15 (10) days according to the A1B (B1) scenario until
2021–2050 and by 48 (29) days until 2071–2100 (Fig. 1.3). In contrast, the number
of days with PET > 29 °C will rise by 5 (15) days until the mid (end) of the twentyfirst century according to the A1B scenario.
J. Fallmann et al.
1.3.2.1 Data and Methods
Regional climate simulations of the ENSEMBLE RT2B model (for more information see http://ensembles-eu.metoffice.com/) with daily resolution are used as the
data basis for the analysis of climate change in the greater region of Stuttgart for
1960–2100. The RT2B model focuses on the SRES A1B scenario. The regional
climate model REMO (for more information see http://www.remo-rcm.de/) in
hourly resolution and 10 km spatial resolution focusing on SRES A1B and B1 scenario is used to analyze the human thermal comfort conditions.
Therefore, the thermal index Physiologically Equivalent Temperature (PET;
Höppe 1993; Mayer and Höppe 1987; Matzarakis et al. 1999) is calculated with the
help of the micro-climate model RayMan (Matzarakis et al. 2007, 2010). PET is
used to quantify especially the frequency and intensity of heat stress. Thereby,
PET between 18 °C and 23 °C was assessed to be comfortable, while PET above
35 °C (Nastos and Matzarakis 2012) stands for strong heat stress (Matzarakis and
Mayer 1996).
The dataset is used to calculate the number of climatologically event days and
their change until the end of the twenty-first century.
1.3.2.2 Results
Table 1.3 shows the frequency of climatological event days. The frequency of hot
days (Tamax ≥ 30 °C) and summer days (Tamax ≥ 25 °C) will increase to 174 % and
140 % in the period 2021–2050 and 280 % and 157 % until end of the twenty-first
century. On the other hand the number of frost (Tamax ≤ 0 °C) and ice days
(Tamax ≤ 0 °C) per year will decrease to 33 % in the period 2071–2100.
The average annual air temperature might rise by 1.5 °C from 1961–1990 to
2021–2050 and 3.5 °C until the end of the twenty-first century (Table 1.3). Thereby,
the increase in air temperature is strongest during summer and winter and weakest
in spring.
The number of days per year with heat stress (PET > 35 °C) at 14:00 MEZ will
increase by 6 days from 1961 to 1990 to 2021–2050 and by 28 days until the end of
the twenty-first century according to the REMO data A1B scenario. The B1 data
shows no increase until the mid of the twenty-first century, but an increase of 4 %
(16 days) until 2071–2100 (Table 1.2).
In the early morning (6:00 MEZ), the number of days with (extreme) cold stress
will significantly decrease by 15 (10) days according to the A1B (B1) scenario until
2021–2050 and by 48 (29) days until 2071–2100 (Fig. 1.3). In contrast, the number
of days with PET > 29 °C will rise by 5 (15) days until the mid (end) of the twentyfirst century according to the A1B scenario.
J. Fallmann et al.