key: cord-0995865-jvjx9gyt
authors: Yakubenko, Slava
title: Home alone? Effect of weather-induced behaviour on spread of SARS-CoV-2 in Germany
date: 2021-04-01
journal: Econ Hum Biol
DOI: 10.1016/j.ehb.2021.100998
sha: 27b064c86fd399ce2b38e6bae62a3c5dd7e8f05d
doc_id: 995865
cord_uid: jvjx9gyt

In early 2020 the world was struck by the epidemic of novel SARS-CoV-2 virus. Like many others, German government has introduced severe contact restrictions to limit the spread of infection. This paper analyses effects of weather on the spread of the disease under the described circumstances. We demonstrate that regions reported lower growth rates of the number of the infection cases after days with higher temperatures, no rain and low humidity. We argue that this effect is channelled through human behaviour. The evidence suggests that “good” weather attracts individuals to outdoor (safer) environments, thus, deterring people from indoor (less safe) environments. Understanding this relationship is important for improving the measures aiming at combating the spread of the virus.

•❛❜♦r❛t♦r② ❡①♣❡r✐♠❡♥t t❤❛t s❤♦✇❡❞ t❤❛t ❛t ✸✵❽❛♥ ✐♥❢❡❝t✐♦✉s ✈✐r✉s ✇❛s r❡❝♦✈❡r❛❜•❡ ❢♦r ✉♣ t♦ ✼ ❞❛②s ❢r♦♠ st❛✐♥•❡ss st❡❡• ♦r ✷✶ ❞❛②s ❢r♦♠ ♣❛♣❡r ♥♦t❡s✳ ❋♦r ❡①❛♠♣•❡✱ t❤❡ ♠❛①✐♠✉♠ t❡♠♣❡r❛t✉r❡ ♦❜s❡r✈❡❞ ✐♥ ♦✉r s❛♠♣•❡ ✇❛s ✷✷❽✳ ❙❡❝♦♥❞•②✱ ✇❡ ♣r♦✈✐❞❡ ❡✈✐❞❡♥❝❡ t❤❛t ♣❡♦♣•❡ s♣❡♥❞ ♠♦r❡ t✐♠❡ ✐♥❞♦♦rs✱ ✇❤❡♥ t❤❡ ✇❡❛t❤❡r ✐s ❜❛❞✳ ❚❤❡ t❡♠♣❡r❛t✉r❡s ✐♥ ✐♥❞♦♦r ❡♥✈✐r♦♥♠❡♥ts ❛r❡ s✉❜•❡❝t t♦ ♠✉❝❤ •♦✇❡r ✈❛r✐❛t✐♦♥ ❞✉❡ t♦ ✐♥s✉•❛t✐♦♥ ❛♥❞ ❤❡❛t✐♥❣ t❡❝❤♥♦•♦❣✐❡s✳ ❚❤✐r❞•②✱ ✇❡ ❝❛♥ ❝♦♥s✐❞❡r ❞②♥❛♠✐❝s ♦❜s❡r✈❡❞ ✐♥ ♦t❤❡r ❝♦✉♥tr✐❡s✳ ❋♦r ❡①❛♠♣•❡✱ ✐♥ ❇r❛③✐• t❤❡ ❞❛✐•② ✐♥❝✐❞❡♥❝❡ ✇❛s ❣r❛❞✉❛••② r✐s✐♥❣ ❢r♦♠ ◆♦✈❡♠❜❡r ✷✵✷✵ t✐•• t❤❡ ♠✐❞❞•❡ ♦❢ ❏❛♥✉❛r② ✷✵✷✶✱ ❡✈❡♥ t❤♦✉❣❤ t❤✐s ✐s ❛ ♣❡r✐♦❞ ✇❤❡♥ t❡♠♣❡r❛t✉r❡s ❛r❡ r✐s✐♥❣ ✐♥ t❤❡ ❙♦✉t❤❡r♥ ❤❡♠✐s♣❤❡r❡✳ ■♥ ■♥❞✐❛ ❞❛✐•② ✐♥❝✐❞❡♥❝❡ ✇❛s ✐♥❝r❡❛s✐♥❣ ❞✉r✐♥❣ ❜♦t❤ s✉♠♠❡r ❛♥❞ ♠♦♥s♦♦♥ s❡❛s♦♥✱ r❡❛❝❤✐♥❣ t❤❡ ♣❡❛❦ ✐♥ ♠✐❞✲❙❡♣t❡♠❜❡r✱ ✇❤❡♥ ❞❛✐•② t❡♠♣❡r❛t✉r❡s t❤r♦✉❣❤♦✉t t❤❡ •❛r❣❡st ♣❛rt ♦❢ t❤❡ ❝♦✉♥tr② ✇❡r❡ ❤✐❣❤❡r t❤❛♥ t❤♦s❡ ♦❜s❡r✈❡❞ ✐♥ ♦✉r s❛♠♣•❡✳ ❋✐♥❛••②✱ ✇❡ ✉t✐•✐s❡ t❡♠♣♦r❛• ❛♥❞ s♣❛t✐❛• ✈❛r✐❛t✐♦♥s ✐♥ ✐♠♣♦s❡❞ ❝♦♥t❛❝t r❡str✐❝t✐♦♥s t♦ ❛r❣✉❡ ✐♥ ❢❛✈♦✉r ♦❢ t❤❡ ❜❡❤❛✈✐♦✉r❛• •✐♥❦✳ P❛rt✐❝✉•❛r•②✱ ✇❡ ❝♦♥s✐❞❡r ❛ ❢✉•• ❝♦♥t❛❝t ❜❛♥ ❛s ❛♥ ✐♥t❡r✈❡♥t✐♦♥ t❤❛t ✇❛s ❞❡s✐❣♥❡❞ t♦ r❡❣✉•❛t❡ ❤✉♠❛♥ ❜❡❤❛✈✐♦✉r ❛♥❞✱ ✉♥•✐❦❡ t❡♠♣❡r❛t✉r❡✱ ❤❛❞ ♥♦ ❞✐r❡❝t ❡✛❡❝t ♦♥ t❤❡ ✈✐r✉s✳ ❲❡ ♣r♦✈✐❞❡ ❡✈✐❞❡♥❝❡ t❤❛t ✏❜❛❞✑ ✇❡❛t❤❡r ❛♥❞ t❤❡ ❢✉•• ❝♦♥t❛❝t ❜❛♥ ❛✛❡❝t ♣❡rs♦♥❛• ♠♦❜✐•✐t② ✐♥ s✐♠✐•❛r ✇❛②s✿ t❤❡② ✐♥❝r❡❛s❡ t❤❡ ♥✉♠❜❡r ♦❢ ✈✐s✐ts t♦ ♣•❛❝❡s ♦❢ r❡s✐❞❡♥❝❡ ❛t t❤❡ ❡①♣❡♥s❡ ♦❢ •❡ss ✈✐s✐ts t♦ ♣❛r❦s✳ ❚❤✐s ❡①♣•❛✐♥s ✇❤② ✇❡ ❛•s♦ ♦❜s❡r✈❡ s✐♠✐•❛r ❡✛❡❝ts ♦♥ t❤❡ s♣r❡❛❞ ♦❢ ❙❆|❙✲❈♦❱✲✷✿ t❤❡ ❢✉•• ❝♦♥t❛❝t ❜❛♥ ❛♥❞ •♦✇❡r t❡♠♣❡r❛t✉r❡s ❛r❡ ❛ss♦❝✐❛t❡❞ ✇✐t❤ ❛ ❢❛st❡r ❣r♦✇t❤ ♦❢ ♥❡✇ ✐♥❢❡❝t✐♦♥s✳ ❚❤❡ s❡✈❡r✐t② ♦❢ ❡✈❡r② ❡♣✐❞❡♠✐❝ ❞❡♣❡♥❞s ♦♥ ❛ ♥✉♠❜❡r ♦❢ ❛s♣❡❝ts✳ ❆s ❡❝♦♥♦♠✐sts ✇❡ ❛r❡ ♣r✐♠❛r✐•② ✐♥t❡r❡st❡❞ ✐♥ t❤♦s❡ ❢❛❝t♦rs t❤❛t ❤✉♠❛♥s ❝❛♥ ❝♦♥tr♦•✳ ❚❤❡ ♠❛✐♥ ❣♦❛• ♦❢ t❤❡ ❣♦✈❡r♥♠❡♥t ❞✉r✐♥❣ t❤❡ ♦✉t❜r❡❛❦ ♦❢ ❛♥ ✐♥❢❡❝t✐♦✉s ❞✐s❡❛s❡ ✐s r❡❣✉•❛t✐♥❣ ❤✉♠❛♥ ❜❡❤❛✈✐♦✉r ✐♥ ❛ ✇❛② t❤❛t ✇♦✉•❞ r❡❞✉❝❡ t❤❡ ♥✉♠❜❡r ♦❢ ♣♦t❡♥t✐❛••② ❝♦♥t❛❣✐♦✉s s♦❝✐❛• ❝♦♥t❛❝ts✳ ❍♦✇❡✈❡r✱ ❜❡❢♦r❡ ✐♥tr♦❞✉❝✐♥❣ t❤❡s❡ ♠❡❛s✉r❡s✱ ✐t ✐s ✐♠♣♦rt❛♥t t♦ ✉♥❞❡rst❛♥❞ ✇❤❛t ❛s♣❡❝ts ♦❢ ♦✉r ❜❡❤❛✈✐♦✉r ♣r♦♠♦t❡ ♦r ❤❛•t t❤❡ s♣r❡❛❞ ♦❢ t❤❡ ✈✐r✉s ✐♥ ❣❡♥❡r❛•✳ ■♥ ♦t❤❡r ✇♦r❞s✱ ❡✈❡♥ ❛❜s❡♥t ❛♥② r❡❣✉•❛t✐♦♥ ❢r♦♠ t❤❡ st❛t❡ ♣❡♦♣•❡ ❤❛✈❡ ❤❛❜✐ts t❤❛t ❝❛♥ ❛✛❡❝t t❤❡ ❣r♦✇t❤ r❛t❡ ♦❢ t❤❡ ♥✉♠❜❡r ♦❢ ❞✐s❡❛s❡ ❝❛s❡s✳ ❯♥❞❡rst❛♥❞✐♥❣ t❤❡s❡ ♣❛tt❡r♥s ✐s 

national average y(t) 18mar2020 01apr2020 15apr2020 29apr2020 date 5 10 15 20 national average past max temperature 18mar2020 01apr2020 15apr2020 29apr2020 

❞❛t❡✲✜①❡❞ ❡✛❡❝ts r❡♠♦✈❡s ♣♦t❡♥t✐❛• ♣r♦❜•❡♠ ♦❢ s✐♠✉•t❛♥❡♦✉s tr❡♥❞s ✐♥ ❜♦t❤ ❞❡♣❡♥❞❡♥t ❛♥❞ ❡①♣•❛♥❛t♦r② ✈❛r✐✲ ❛❜•❡s ❛♥❞ ❛••♦✇s ✉s t♦ ❛r❣✉❡ t❤❛t t❤❡ ❡✛❡❝t ♦❢ ✇❡❛t❤❡r ✐s ❝❛✉s❛•✳ |❡s✉•ts ❛r❡ r♦❜✉st t♦ t❤❡ ✉s❡

rts t❤❡ ❤②♣♦t❤❡s✐s t❤❛t t❤✐s ❡✛❡❝t ✐s ♣r✐♠❛r✐•② ❝♦♠✐♥❣

❡✈❡rt❤❡•❡ss ♣♦s✐t✐✈❡✳ ❇❡s✐❞❡s t❤❛t✱ ✇❡ ♣r♦✈✐❞❡ ❡✈✐❞❡♥❝❡ t❤❛t t❤❡ ❝♦♥t❛❝t ❜❛♥ ♣r❡✈❡♥ts ✈✐s✐ts t♦ ♣❛r❦s ❛♥❞ ♣r♦♠♦t❡s ✈✐s✐ts t♦ r❡s✐❞❡♥t✐❛• ❛r❡❛s✳ ❲❡ ✜♥❞ ❛ ♥❡❣❛t✐✈❡ ❡✛❡❝t ♦❢ t❡♠♣❡r❛t✉r❡s ♦♥ ✈✐s✐ts t♦ r❡s✐❞❡♥t✐❛• ❛r❡❛s✱ ❜✉t ♠♦st •✐❦❡•② ✐t ❝♦♠❡s t❤r♦✉❣❤ t❤❡ ✈✐s✐ts t♦ ♣❛r❦s t❤❛t ❛❝t ❛s ❛ s✉❜st✐t✉t❡ ❛❝t✐✈✐t②✳ ❋✐♥❛••②✱ ✇❡ ❞❡♠♦♥str❛t❡ t❤❛t r❡❣✐♦♥s ✇❤❡r❡ t❤❡ ❝♦♥t❛❝t ❜❛♥ ✇❛s ✐♠♣♦s❡❞✱ ❜❡♥❡✜t❡❞ ❢r♦♠ ❤✐❣❤

t❡♠♣❡r❛t✉r❡s s✐❣♥✐✜❝❛♥t•② ♠♦r❡✳ ❆t t❤❡ s❛♠❡ t✐♠❡✱ t❤❡ ❝♦♥t❛❝t ❜❛♥ r❡s✉•t❡❞ ✐♥ ❤✐❣❤❡r ❣r♦✇t❤ r❛t❡

ts ❢❛❝✐•✐t❛t❡ s❡❝♦♥❞❛r② tr❛♥s♠✐ss✐♦♥ ♦❢ ❝♦r♦♥❛✈✐r✉s ❞✐s❡❛s❡ ✷✵✶✾ ✭❈❖❱■❉✲✶✾✮✳ ♠❡❞|①✐✈✱ ❤tt♣s✿✴✴✇✇✇✳♠❡❞r①✐✈✳♦r❣✴❝♦♥t❡♥t✴❡❛r•②✴✷✵✷✵✴✵✹✴✶✻✴✷✵✷✵✳✵✷✳✷✽✳✷✵✵✷✾✷✼✷✳❢✉••✳♣❞❢✳ ❤tt♣s✿✴✴❞♦✐✳♦r❣✴✶✵✳✶✶✵✶✴✷✵✷✵✳✵✷✳✷✽✳✷✵✵✷✾✷✼✷

r r❡✐♥❢❡❝t✐♦♥ ✇✐t❤ ❙❆|❙✲❈♦❱✲✷✿ ❛ ❝❛s❡ st✉❞②✳ ❚❤❡ ▲❛♥❝❡t ■♥❢❡❝t✐♦✉s ❉✐s❡❛s❡s✱ ✷✶ ✭✶✮✱ ✺✷✕✺✽✳