22 | New Scientist | 14 May 2022Extreme weatherTHE worst heatwaves recorded
have now been identified, including
five that were more severe than the
deadly western North American
heatwave last year.
“We started by looking at the
heatwave last June in the US and
Canada, which... everyone was
quite shocked by. Then we found
five events that were more extreme
than that,” says Vikki Thompson at
the University of Bristol, UK. These
were in southern Brazil in 1985,
South-East Asia in 1998, south-
west Peru in 2016, south-east
US in 1980 and Alaska in 2019.
“Many of these events are
in parts of the world where they
were missed because they had less
impact on us in the Western world,
or where there are less people and
they’re just not monitored so well,”
says Thompson. She and her teamstarted by analysing historical
temperature data from 158 regions
of the world from 1968 to 2021.
They used a climate model to fill
in gaps in measurements, before
pinpointing daily temperatures in
each region that were so high there
was less than a 0.1 per cent chance
of them occurring normally. Many
regions – including most of Africa –
weren’t included due to a lack of
reliable data, says Thompson.
The team also predicted how
common heatwaves would be in
North America under various global
warming scenarios. In a worst-case
scenario, with a 4.3°C increase in
average global temperature by the
end of the century, it estimated
a 1-in-6 chance of an extreme
heatwave occurring each year
by the 2090s (Science Advances,
doi.org/hs29). Carissa WongFive recent mega heatwaves
that slipped under the radar
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News In brief
A VACCINE that wards off the
common Epstein-Barr virus to
potentially prevent glandular
fever, multiple sclerosis (MS)
and even some cancers has
shown promise in mice, ferrets
and monkeys. A human trial
is expected to start in 2023.
Gary Nabel at ModeX
Therapeutics in Natick,
Massachusetts, and his team
developed a vaccine that exposes
the body to two proteins that
Epstein-Barr virus uses to invade
cells, training the immune system
to recognise the pathogen. Initial
tests showed that mice, ferrets
and rhesus macaques developed
antibodies against Epstein-Barr
virus post-vaccination.
To better understand the jab’s
potential in people, the researchers
engineered mice with human-like
immune systems. When exposed
to Epstein-Barr virus, only 17 perHealth^cent of the mice became infected
after receiving antibodies from
other vaccinated rodents. In
contrast, 100 per cent of the
mice without antibodies became
infected (Science Translational
Medicine, doi.org/gp3x6n).
None of the mice given
vaccine-induced antibodies
developed lymphomas – cancers
of the lymphatic system that
are increasingly being linked
to Epstein-Barr virus – but half
of the unprotected rodents did.
The team didn’t look into other
Epstein-Barr-related conditions,
such as stomach cancer.
More than 95 per cent of
adults worldwide are infected
with Epstein-Barr virus, a type
of herpes that most commonly
spreads via saliva. It is known to
cause glandular fever, also called
“mono”, and is associated with MS.
If the vaccine is shown to be
safe and effective in people, it
could be given to children to
prevent Epstein-Barr-related
conditions, says Nabel. Alice KleinJab for glandular
fever virus testedSWAPPING a fifth of the world’s
meat consumption for eating
meat-free microbial protein
made in factories would more
than halve global deforestation
and related carbon emissions.
Cattle ranches and crops
grown to feed cows are two of
the biggest drivers of trees being
cleared across the tropics, which
is continuing despite political
pledges to curb the loss ofDietcarbon-rich, biodiverse habitats.
Microbial proteins, such as
the Quorn mycoprotein made
from a fungus and sugar in heated
vessels, have already been shown
to have a lower environmental
impact than meat from ruminants
such as cows and sheep. But their
future potential – as populations
grow, food demand rises and diets
shift – hasn’t been fully explored.
So Florian Humpenöder at the
Potsdam Institute for Climate
Impact Research in Germany
and his colleagues modelled
what would happen in various
scenarios, including 20 per cent
of ruminant meat consumption
per person being substituted for
microbial proteins by 2050.
They found that this scenario
would cut deforestation greatly,
from 8.4 million hectares annually
compared with business as usual,
to 3.7 million hectares. Net carbon
dioxide emissions would fall
from 5.5 billion tonnes in 2050 to
2.4 billion (Nature, doi.org/hs3j).
SIM Adam VaughanONDAWSON/BLOOMBER
G^ VIA^
GE
TTY^ IMAGESEat microbial protein
to spare the forests