Indices for Heat Health Warning Systems – General Considerations –
Christina Koppe – Deutscher Wetterdienst (DWD)
2Quelle: Fotalia
Single & multi-parameter indices
Simplifiedbiometeoro-logical indices
Holistic (air mass based) approaches
Heat budget approaches
Considerationof adaptation
Chicago Workshop 2015
Perfect Heat Health Warning System
3
Picture Source: Fotalia
Perfect Heat Health Warning System
• Forecast skill
• Health relevance
reliable easy to handle effective
• No complicated modelling
• Easy to implement
• Low requirements for input data
• universal
• Trigger interventions to prevent heat related health impacts
• communication
• sufficient lead time
Single & multi-parameter indices
Chicago Workshop 2015
Indices for Heat Health Warnings
4
Single & multi-parameter indices
� Single: Tmax, Tmean
� Multi: simple combination of parametersExample single-parameter: Latvia Tmax
Level 1 (potentially dangerous) : max air temperature between 27°C and 32°C for 2 days or more
Warning-threshold has to be fitted to mortality data
Level 2 (dangerous): max. air temperature above 32°C
Chicago Workshop 2015 5
Single & multi-parameter indices
� Single: Tmax, Tmean
� Multi: simple combination of parametersExample multi-parameter: France 3 day average of 99,5th percentile Tmax (31-36°C) and Tmin (18-24°C)
Level 1: seasonal vigilance (1 June - 31 August)
Level 3: warning and action (thresholds are reached for 3 days or more)
Level 4: maximal mobilization (very long and intensive)
Level 2: short heat wave (1 or 2 days)
Indices for Heat Health Warnings
Chicago Workshop 2015
Perfect Heat Health Warning System
6
Picture Source: Fotalia
Perfect Heat Health Warning System
• Forecast skill
• Health relevance
reliable easy to handle effective
• No complicated modelling
• Easy to implement
• Low requirements for input data
• universal
• Trigger interventions to prevent heat related health impacts
• communication
• sufficient lead time
Single & multi-parameter indices
Chicago Workshop 2015
Perfect Heat Health Warning System
7
Picture Source: Fotalia
Perfect Heat Health Warning System
• Forecast skill
• Health relevance
reliable easy to handle effective
• No complicated modelling
• Easy to implement
• Low requirements for input data
• universal
• Trigger interventions to prevent heat related health impacts
• communication
• sufficient lead time
Simplifiedbiometeoro-logical indices
Chicago Workshop 2015
Indices for Heat Health Warnings
8
Simplifiedbiometeoro-logical indices
e.g. Heat Index, Humidex, wet-bulb globe temperature, apparent temperature
Example Switzerland : Heat Index
Chicago Workshop 2015 9
Simplifiedbiometeoro-logical indices
e.g. Heat Index, Humidex, wet-bulb globe temperature, apparent temperature
Example Switzerland : Heat Index
Level 1 (considerable danger): HI > 90 for 3 consecutive days
Level 2 (great danger): HI > 93 for 5 consecutive days
Indices for Heat Health Warnings
Chicago Workshop 2015
Perfect Heat Health Warning System
10
Picture Source: Fotalia
Perfect Heat Health Warning System
• Forecast skill
• Health relevance
reliable easy to handle effective
• No complicated modelling
• Easy to implement
• Low requirements for input data
• universal
• Trigger interventions to prevent heat related health impacts
• communication
• sufficient lead time
Simplifiedbiometeoro-logical indices
Chicago Workshop 2015
Perfect Heat Health Warning System
11
Picture Source: Fotalia
Perfect Heat Health Warning System
• Forecast skill
• Health relevance
reliable easy to handle effective
• No complicated modelling
• Easy to implement
• Low requirements for input data
• universal
• Trigger interventions to prevent heat related health impacts
• communication
• sufficient lead time
Holistic (air mass based) approaches
Chicago Workshop 2015
Perfect Heat Health Warning System
12
Picture Source: Fotalia
Perfect Heat Health Warning System
• Forecast skill
• Health relevance
reliable easy to handle effective
• No complicated modelling
• Easy to implement
• Low requirements for input data
• universal
• Trigger interventions to prevent heat related health impacts
• communication
• sufficient lead timeHeat budget approaches
Chicago Workshop 2015
Indices for Heat Health Warnings
13
Heat budget approaches
e.g. Perceived Temperature PT (SET*, PET, UTCI)
Example Germany:
PT + adaptation approach (HeRATE) + OT
absolute part relative part
inclusion of absolute limits due to the constrain of keeping the core
temperature constant
short term adaptation (acclimatisation + behavioural adaptation)
extreme heat load4≥ 38
strong heat load332 to 38
moderate heat load226 to 32
slight heat load120 to 26
thermal comfort00 to 20
slight cold stress-1-13 to 0
moderate cold stress-2-26 to -13
strong cold stress-3-39 to -26
extreme cold stress-4≤ -39
Thermal load categoryPT (°C)
extreme heat load4≥ 38
strong heat load332 to 38
moderate heat load226 to 32
slight heat load120 to 26
thermal comfort00 to 20
slight cold stress-1-13 to 0
moderate cold stress-2-26 to -13
strong cold stress-3-39 to -26
extreme cold stress-4≤ -39
Thermal load categoryPT (°C)
extreme heat load4≥ 38
strong heat load332 to 38
moderate heat load226 to 32
slight heat load120 to 26
thermal comfort00 to 20
slight cold stress-1-13 to 0
moderate cold stress-2-26 to -13
strong cold stress-3-39 to -26
extreme cold stress-4≤ -39
Thermal load categoryPT (°C)
extreme heat load4≥ 38
strong heat load332 to 38
moderate heat load226 to 32
slight heat load120 to 26
thermal comfort00 to 20
slight cold stress-1-13 to 0
moderate cold stress-2-26 to -13
strong cold stress-3-39 to -26
extreme cold stress-4≤ -39
Thermal load categoryPT (°C)
-10
0
10
20
30
40
50
Jan 84 Mrz 84 Mai 84 Jul 84 Sep 84 Nov 84 Jan 85Date
Per
ceiv
ed T
empe
ratu
re (
°C)
PT 12
weightedPT12
2/3 1/3
Index: Perceived Temperature (PT)
Complete heat budget model of human bodyStandardizations: • Standard Person (Klima-
Michel)• Standard Environment
Chicago Workshop 2015 14
Heat budget approaches
Indices for Heat Health Warnings
e.g. Perceived Temperature PT (SET*, PET, UTCI)
Example Germany:
PT + adaptation approach (HeRATE) + OT
Operative Temperature OT calculated by building simulation modelStandardizations: • Building type• User behaviour
Level 1: variable threshold for strong heat load is exceeded for 2 consecutive days and indoor mean operative temperature during nighttime is higher than ~ 24°C
Level 2 : threshold for extreme heat load is exceeded (PT [12 UTC] >38°C)
Chicago Workshop 2015
Perfect Heat Health Warning System
15
Picture Source: Fotalia
Perfect Heat Health Warning System
• Forecast skill
• Health relevance
reliable easy to handle effective
• No complicated modelling
• Easy to implement
• Low requirements for input data
• universal
• Trigger interventions to prevent heat related health impacts
• communication
• sufficient lead time
Heat budget approaches
HHW-IndicesHeat budget approaches
� e.g. Perceived Temperature PT (SET*, PET, UTCI)
Example Germany : PT + adaptation approach (HeRATE)
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Disadvantages
� Relatively complex (2 models: indoor and PT)
� Difficult to communicate� Skill on climate time scales
problematic (radiation, humidity and wind are input parameters)
Level 1: variable threshold for strong heat load is exceeded for 2 consecutive days and indoor mean operative temperature during nighttime is higher than 24°C
Level 2 : threshold for extreme heat load is exceeded (PT [12 UTC] >38°C)
Advantages
� Physiologically relevant� no fitting to local climate needed
(exception extreme climatic conditions)
� Adaptation is included
Chicago Workshop 2015
1986-1998
Chicago Workshop 2015
Perfect Heat Health Warning System
17
Picture Source: Fotalia
Perfect Heat Health Warning System
• Forecast skill
• Health relevance
reliable easy to handle effective
• No complicated modelling
• Easy to implement
• Low requirements for input data
• universal
• Trigger interventions to prevent heat related health impacts
• communication
• sufficient lead timeHeat budget approaches
Chicago Workshop 2015
Perfect Heat Health Warning System
18
Picture Source: Fotalia
Perfect Heat Health Warning System
• Forecast skill
• Health relevance
reliable easy to handle effective
• No complicated modelling
• Easy to implement
• Low requirements for input data
• universal
• Trigger interventions to prevent heat related health impacts
• communication
• sufficient lead time
Consider-ation of adaptation
Chicago Workshop 2015
Indices for Heat Health Warnings
19
Consider-ation of adaptation
e.g. HeRATE, Excess Heat Index acclimatisation (EHIaccl)
Example Germany / EuroHEAT : T12 UTC + HeRATE
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22
24
26
28
30
32
34
36
38
40
0 10 20 30 40 50
weighted mean temperature of the last 30 days
wea
ther
thre
shol
d
Information about probability that threshold for heat is reached or exceeded (lead time 10 days)
Chicago Workshop 2015
Indices for Heat Health Warnings
20
e.g. HeRATE, Excess Heat Index acclimatisation (EHIaccl)
Example Germany / EuroHEAT : T12 UTC + HeRATE
Information about probability that threshold for heat is reached or exceeded (lead time 10 days)
Consider-ation of adaptation
Chicago Workshop 2015
Perfect Heat Health Warning System
21
Picture Source: Fotalia
Perfect Heat Health Warning System
• Forecast skill
• Health relevance
reliable easy to handle effective
• No complicated modelling
• Easy to implement
• Low requirements for input data
• universal
• Trigger interventions to prevent heat related health impacts
• communication
• sufficient lead time
Consider-ation of adaptation
Summary and Conclusions
• There are many indices / methods used for HHWS
• Perfect index / method should:
� directly linked to health impacts� include adaptation / acclimatization� model individual thermal stress level
� be universally applicable and easy to handle
� good forecast / prediction skill on all time scales
• All indices have the problem that they try to assess the thermal load on populations basis
• Warning method should be tailored to local requirements (health interventions) and data availability (forecasts, historical data, health data)
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There is no best method for triggering heat warning s
Chicago Workshop 2015
Quelle: Fotalia
Future
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There is no best method for triggering heat warning s
Chicago Workshop 2015
Quelle: Fotalia
Heatwarnings
Heatwarnings
Keep it simpleKeep it simple IndividualizationIndividualization
PBPV – 10/2013 24
Thank You