34 | NewScientist | 18 January 2014

In AD 536 the sun dimmed and global temperatures plunged, leading to famine, plague and the collapse

of empires. At last clues are emerging about the cause of this event, as Colin Barras reports

The year of darkness

“ The sun began to be darkened by day and the moon by night, while the ocean was tumultuous with spray from the 24th of March in this year till the

24th of June in the following year… And, as the winter was a severe one,

so much so that from the large and unwonted quantity of snow the birds

perished… there was distress… among men… from the evil things”

ZACHARIAS OF MYTILENE (Chronicle, 9.19, 10.1)

18 January 2014 | NewScientist | 35

ALAI

N W

ILLA

UM

E/TE

NDA

NCE

FLO

UE

T

>

140118_F_AD536.indd 35 13/1/14 11:42:07

” The sun became dim… for nearly the whole year… so that the fruits were killed at an unseasonable time.”

36 | NewScientist | 18 January 2014

The plague of Justinian

“ There was a sign in the sun the like of which had never been seen and reported before… The sun became dark and its darkness lasted for eighteen months. Each day it shone for about four hours, and still this light was only a feeble shadow. Everyone declared that the sun would never recover its full light. The fruits did not ripen and the wine tasted like sour grapes”MICHAEL THE SYRIAN (Chronicle, 9.296)

1

0

-1

-2

-3500 520 540

Date (AD)

Devi

atio

n of

ext

ratr

opic

al n

orth

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hem

isph

ere

tem

pera

ture

from

nor

m (°

C)

560 580 600

Climate catastropheTree rings and other records show the world suddenly cooled around AD 536, a period marked by famines, plagues and turmoil. But what caused it?

The Plague of Justinian kills a quarter of the population of the Eastern Roman Empire

The Northern Wei dynasty of China collapses and three-quarters of the

population dies

A comet fragment may have hit the Gulf of

Carpentaria sometime in the first millennium

The Ilopango volcano erupted in the 5th or 6th century

The huge city state of Teotihuacan declines

SOUR

CE: C

HRI

STIA

NSEN

201

1

18 January 2014 | NewScientist | 37

LEFT

: MAT

JACO

B/TE

NDA

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RIGH

T : D

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V VA

N R

AVEN

SWA

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CIEN

CE P

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SCA

LA, F

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NCE

- CO

URT

ESY

OF

THE

MIN

ISTE

RO B

ENI E

ATT

. CU

LTU

RALIThe Plague of Justinian was an early form of the

bubonic plague that caused the Black Death

Chinese records suggest Halley’s comet shed more dust and debris than usual in AD 530

38 | NewScientist | 18 January 2014

Impact site

Colin Barras is a freelance writer based in Ann Arbor, Michigan

“ And it came about during this year that a most dread portent took place. For the sun gave forth its light without brightness, like the moon, during this whole year, and it seemed exceedingly like the sun in eclipse, for the beams it shed were not clear nor such as it is accustomed to shed”PROCOPIUS (Wars, 4.14.5)

Things got so bad in the city state of Teotihuacan that people burned down the temples on pyramidsRO

BERT

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RCK/

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