11 December 2021 | New Scientist | 9THE founder of plant-based
“meat” firm Impossible Foods
is talking to UK farmers about
a pilot project to swap livestock
for trees to fight climate change.
Pat Brown, a scientist
at Stanford University in
California, set up the fast-
growing company in 2011. He
says he wants to demonstrate
the economic benefits of taking
farmland out of cattle and sheep
production to allow forests to
grow on it and absorb carbon.
Brown argues that livestock
farmers would be better off
as a result by selling carbon
offsetting permits to airlines
and other polluting industries.
“It’s very nascent. What I’m
interested in doing is kind of
like a... demonstration project
to show that it is actually very
financially sound to buy land
from livestock farmers and
manage it for biomass recovery
and sell carbon offsets,” Brown
tells New Scientist.
He is one of a rising number
of experts proposing that land
for meat production will need tobe freed up to grow trees that
suck carbon dioxide out of the
atmosphere if the world is to
meets its climate goals. The UK
government’s statutory climate
advisers want to see a fifth of
farmland there turned over
to grow trees to store carbon.
“Almost every livestock
farmer on Earth would make
more money at $50 (£38) a
tonne [of carbon dioxide],
accumulating [plant] biomass
on their land as opposed to
livestock,” says Brown. The
price of a tonne of CO2 in the
UK’s post-Brexit carbon trading
scheme has been over £50 in
recent months.
On a recent trip to the UK
for the COP26 climate summit
in Glasgow, Brown spoke to
farmers about hosting a trial
project. He says there was some
scepticism, but he believes the
wider adoption of the idea could
be appealing because “those
farmers are making a pittance
right now”.
“I agree with the idea in
principle,” says Pete Smith at the
University of Aberdeen in the
UK. “I can see why it is met with
some scepticism though –
livestock farmers are notforesters. We need to find a
way of transitioning away from
livestock farming in a way that
works for farmers.”
Brown says he was
disappointed that speeding
up the phase-out of animal
agriculture to cut emissions
wasn’t high on the agenda
at COP26. “This should be
the number one topic at COP,
because there’s nothing thatcomes close for having a fast
and dramatic impact on climate
change,” he says.
A recent paper by Brown, not
yet peer-reviewed but accepted
for publication, calculates that
phasing out animal agriculture
in 15 years and allowing trees
and other plants to grow on the
land involved would provide
around half the emissions
savings needed to meet the
Paris Agreement’s goal of
holding temperatures below 2°C
this century. Previous studies
came to similar conclusions.
The UK’s National Farmers’
Union (NFU) says carbon
markets hold potential
opportunities for farmers.
But Stuart Roberts at the NFU
says: “We really must move
away from the idea that all
livestock production is the
same the world over and by
simply removing it from the
equation we solve the climate
change crisis overnight. This
simply isn’t the case.”
A spokesperson for
Impossible Foods says: “We
continue to explore new ways
to work with farmers to support
initiatives that provide the best
value for their land.” ❚Pat Brown with
Impossible Foods’
plant-based burgerClimate changeAdam VaughanROBYN^ BEC
K/AFP
VIAGETT
Y^ IMAGES20%
slice of farmland needed for
tree-planting, say UK advisersFake-meat boss wants farms
to swap livestock for trees
SURVEILLANCE cameras can keep
us safe or invade our privacy, and
improvements in miniaturisation
mean they can now be hidden in
almost any object. Now there is a
smartphone app that helps users
detect such hidden cameras.
Commercial devices to spot
hidden cameras are available,
but carrying a specific device for
this purpose is inconvenient. Sriram
Sami at the National University of
Singapore and his colleagues hope
to provide the same function via
a standard smartphone.
Their system uses a time-
of-flight sensor, which emits
a beam of infrared light and
measures how long it takes to
be reflected from an object. The
sensors have become increasingly
common in smartphones and
are used to improve the quality
of photographs.
Sami and his team created
a smartphone app that uses
information from these sensors
to spot the unique reflections from
hidden cameras. The app detects
any spots on the object where the
incoming light is brighter, which
indicates a reflective surface and
potentially a camera lens. It uses
machine learning techniques to
separate innocuous results from
suspicious ones.
The researchers recruited
379 people and showed them
videos of 30 different objects
recorded from less than a metre
away. They had to identify if they
saw any hidden cameras and mark
the location of them. With the naked
eye, the volunteers spotted the
cameras 46 per cent of the time,
whereas the AI tool had a success
rate of 88.9 per cent (SenSys ’ 21 ,
doi.org/gnh87c).
“Users can trade off between
catching more hidden cameras
but dealing with more false
positives and vice versa just by
adjusting a slider,” says Sami. ❚TechnologyMatthew SparkesSmartphone app
detects hidden
camera lenses