Will Climate Warming Decrease

Winter Mortality in Europe?

Joan Ballester

Institut Català de Ciències del Clima (IC3)

with the collaboration of

Jean-Marie Robine, François Richard Herrmann, Xavier Rodó

Our Common Future Under Climate Change

Health and Climate Change: the Need for a Diversity of Approaches

UPMC Jussieu, Paris, July 8th 2015

The research leading to these results has been funded by

the Marie Curie Actions of the European Commission’s

Seventh Framework Research Programme.

Sensitivity to cold temperatures

Large differences in the slopes of the relationship

Higher sensitivity in the Mediterranean and the British Isles

Lower sensitivity in central, eastern and northern Europe

Ballester et al. (2011) Nature Communications

Healy (2003)

Year-to-year relation in the UK Staddon et al. (2014) Nature Climate Change

Declining year-to-year relation between

– Number of winter days

– Excess winter deaths (EWDs)

Conclusion: climate warming will not decrease winter mortality

Vivid scientific debate Hajat and Kovats (2014) and Staddon et al. (2014)

Comment by

Hajat and Kovats (2014)

Nature Climate Change

Reply by

Staddon et al. (2014)

Nature Climate Change

Adaptation to cold winter days

Regression coefficients between: – daily winter temperature

– daily winter mortality

Countries with mild winters are more sensitive to cold temperatures

Mild climate

More sensitive

Cold climate

Less sensitive

Coherent with Healy (2003)

Adaptation to winter mean temperatures

Year-to-year correlations between: – winter mean temperature

– winter mean mortality

Large values everywhere, except the UK, the Netherlands and Belgium

Coherent with Staddon et al. (2014) Coherent with Healy (2003)

Comparison at the country level

No spatial relation between regressions and correlations,

suggesting two types of acclimatization processes.

Country Year-to-year correlation

Portugal -0.97

Croatia -0.97

Italy -0.96

Austria -0.96

Slovenia -0.93

Switzerland -0.88

Spain -0.88

Czech Republic -0.88

Germany -0.85

France -0.83

Luxembourg -0.81

Poland -0.70

Denmark -0.60

United Kingdom -0.12

Netherlands 0.08

Belgium 0.38

Country Day-to-day

regression coeff.

Portugal -1.13

Spain -0.67

Italy -0.52

United Kingdom -0.38

France -0.26

Czech Republic -0.25

Austria -0.24

Croatia -0.23

Belgium -0.22

Denmark -0.21

Slovenia -0.20

Poland -0.18

Luxembourg -0.17

Germany -0.16

Switzerland -0.15

Netherlands -0.14

Spatial

correlation:

r = 0.16 (not signif.)

Low

vulnerability

Large

adaptation

High

vulnerability

Low

adaptation

Daily vs. seasonal acclimatization

Temperature PDF

T/M relationship

β small

β large

Daily vs. seasonal acclimatization

Temperature PDF

T/M relationship

Interannual anomalies:

∆T: temperature

β small

β large

Daily vs. seasonal acclimatization

β small

β large α ≈ 1

α ≈ 0

Temperature PDF

T/M relationship

Interannual anomalies:

∆T: temperature

∆R: response

Long-term adaptation to mean temperatures

The spatial variability of the comfort temperatures suggests

an (incomplete) long-term adaptation to environmental temperatures

spatial correlation: 0.69

spatial regression: α’ = 0.5

∆R’ = α’ · ∆T’ + ε

M

T

T’ R’

Implications: projections of mortality

Ballester et al. (2011) Nature Communications

Very few studies have considered the “seasonal acclimatization”

Mortality projections are highly sensitive to the adaptation coefficient

x106

Take-home messages

Results confirm (and generalize) the seasonal acclimatization to

winter temperatures from Staddon et al. (2014).

Potential for inter-country comparison of adaptation policies:

– daily: northeastern vs. southern Europe,

– seasonal: UK+Benelux vs. others.

Mortality projections should include adaptation coefficients.

The contribution of temperature rise to the decline of winter

mortality has been overestimated in some countries.

Thanks!

Poster session:

“Integrating climate information into decision support tools for public health”

UPMC Jussieu – Posters (Block 24)

––––– ––––– ––––– ––––– –––––

joanballester@ic3.cat

The research leading to these results has been funded by

the Marie Curie Actions of the European Commission’s

Seventh Framework Research Programme.