13 July 2019 | New Scientist | 13Forensic scienceAN OVERSIGHT in historical weather
records means we underestimated
how much the climate warmed
in the past century or so. The
finding means we are 0.1°C closer
than we thought to passing the
internationally agreed absolute
upper limit of 2°C of warming.
The problem stems from where
the first weather stations were setup. Most early measurements come
from Europe, the US and regions
along trade routes – around 20 per
cent of Earth’s area, says Rasmus
Benestad at the Norwegian
Meteorological Institute in Oslo.
Some climate deniers have
argued this means records are
too incomplete to be reliable, but
temperatures are generally similar
across regions, so climatologists
have been able to fill in the gaps.
However, Benestad and his
colleagues found a subtler problem.
The early weather stations were allin regions where the temperature
doesn’t vary too much over time.
Only later were stations built in
places like Siberia, where month-
to-month changes are larger.
To find out if this was an issue,
Benestad’s team ran computer
models of the global climate
from 1861 to 2017 and noted
how the simulated global averagetemperature changed. Then,
they ran the models again using
data corresponding to the weather
stations that were present in each
year (Geophysical Research
Letters, doi. org/c7x8).
They found the early weather
station sites created a problem. The
older records came out slightly too
warm, while more recent ones were
slightly too cold. The net result was
that the combined warming from
1881 to 1910 and 1986 to 2015
was underestimated by 0.1°C. ❚ONE of the oldest ever cold cases
has been confirmed as murder,
33,000 years after the crime
was committed. The weapon?
A baseball bat-like implement.
The Cioclovina calvaria (or
skull cap) specimen was found
in a cave in Transylvania, Romania,
in 1941 by miners searching for
phosphate. It is one of the oldest
partial skulls of an early modern
human in Europe in the Upper
Palaeolithic period yet found.
There are extensive fractures
on one side of the skull, but their
cause was a mystery. Forensic
scientist Elena Kranioti at the
University of Crete, Greece, and
her colleagues decided to apply
modern forensic techniques
in search of an answer.
They looked for signs of
whether the bones were broken
before or after death. Kranioti
knew that if the skull was damaged
long after Cioclovina man had
died, the fractures would be in
random patterns and be square-
shaped with sharp edges, because
old and dry bone breaks in a
different way to “living” bone.
Instead, they found characteristics
that suggest the damage occurred
at around the time of death.Then, using CT scans, they
discovered that there were
no signs of healing around
the fractures, indicating that
Cioclovina man didn’t recover
from his injuries.
The next step was to
determine whether Cioclovina
man’s fractures were caused by
a fall, being hit on the head with
a rock, or something else.
The pattern of the fractures gave
Kranioti and the team some clues.
A fairly straight fracture stretched
across the skull, while anothermore circular fracture pushed
fragments inwards into the brain.
While the cracks from
the circular fracture radiated
outwards, they stopped when they
met the straight line, meaning
the straight fracture came first.
“The distinctive [circular]
depressed fracture found on
the right side of the skull is
unquestionably evidence thatthe person was struck with a blunt
object, which directly implies a
human agent,” says Kranioti.
The researchers then recreated
the blow on artificial skulls filled
with ballistic gelatin. They tested
several scenarios, including falls
and blows with a rock or a baseball
bat, to different locations on the
skulls. The fracture patterns found
on Cioclovina man’s skull strongly
resemble what happened when
the artificial skulls were hit twice
with a round, club-like object
while against the ground
(PLoS One, doi.org/c7zk).
“The linear fracture happened
first and could have been a result
of a person falling from their own
height – while running from
someone, for example,” says
Kranioti. The second fracture
is a result of violence, she says.
“Which means that, in modern
terms, if I had to define the cause
and matter of death as a forensic
pathologist, I would say that the
person died of craniocerebral
injuries and that it was homicide,”
says Kranioti.
Stanley Serafin at the University
of New South Wales, Australia, says
the authors present a “thoroughly
convincing case”. ❚“The net result was that
the combined warming
over the period was
underestimated by 0.1°C”Climate change
The skull has fractures
typical of modern attacks
with baseball batsRuby Prosser ScullyKR
ANIOTI^ ETAL,^2019Stone Age human was murdered
Injury patterns on an ancient skull strongly indicate an early case of homicide
Earth warmed more
than we thought
last centuryMichael Marshall