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Give a warm applause
for Dr. Benjamin
Leon Bulahdelah ski.
Doctoral researcher at the Potsdam
Institute for Climate Impact
Research, and he's designing
quantitative computer models.
And global nitrogen cycle
simulation, so it's like civilization
eight nor with more realistic.
And what we can learn from it and what
how we can use it.
You will hear now.
Station,
what we are doing there is we are doing
computer simulations
of all kinds of sciences, from
natural sciences to social sciences,
um, but this campus
has actually a long history already
of science.
So it used to be the Astrophysical
Institute at the Astrophysical
Observatory and Metrological
Observatory, and quite
a few experiments were carried out there.
So we, um,
there was the Gevalia measure, the
value of gravity.
The first earthquake was recorded or
some equations
of the relativity theory
of the field equations were solved
in this former institute since
1990. Now it's
the Potsdam Institute for Climate Impact
Research.
And what you can see nicely here, these
buildings are still the old cupolas,
which show which have inside
or which used to have inside large
telescopes.
And these telescopes are a bit a symbol
for the first
scientific revolution, the first
Copernican revolution,
which happened about
400 years ago.
And the scientific revolution
was sparked by
the technical development of lenses
which allow you to use microscopes
or telescopes.
And this opened
up a new field of research because
suddenly you could see things which
were quite small, even
larger, you could see things
in detail, and you suddenly
had a view inside
the huge complexity,
both inside a cell or
inside of our universe.
Some scholars argue that today now
we are living in the second Copernican
revolution and this
second Copernican revolution is
triggered by the development of so-called
microscopes.
Probably nobody of you ever heard this
word because it's invented.
Um, hello, translators.
But maybe you can
think what it means.
It's kind of the inverse of a microscope
instead of showing you things
in more detail.
Actually, it has to be because it shows
you things in less detail.
It reduces the complexity
of the real world.
And this is something that is really
necessary because the complexity of the
real world is sometimes overwhelming.
And if you want to make decisions, we
sometimes need simpler
versions of the real world to understand
them.
So how can a microscope look like?
Well, the first approach is quite
straightforward.
If you want to see something in
less detail, you just go
go one step back or
two step X or even further.
So one option is a satellite
from out of this.
If you look from a satellite on the
earth, you can see the
micro development on the planet.
And while
things that you can see is first of all,
the Earth is quite a beautiful planet,
but you can also see
what's happening on the planet right now,
that the streets are
going into pristine forests, that
we are burning down forests all
over the world.
Um, that at
nighttime the earth is still illuminated
by electric lights from the cities.
And you can see how strongly
we already shape the way
the planet looks like today.
You can clearly see that we are now
living already in the Anthropocene.
A second option to see
the earth system
in a reduced form is
you can rebuild it in a smaller scale.
This has been this has been carried
out in the 1990s with the
Biosphere two experiment.
It's basically a whole earth system in a
glass house, in a confined glass house,
which has an ocean, which has a
rainforest and a desert,
and also eight human scientists
living within.
And you can see
it as a successful failure in the
way that, um,
after a very short time already
the whole ecosystem collapsed.
The fish in the oceans died,
the ecosystems were run over by
cockroaches and ends.
The CO2 levels rose extremely.
And the scientists, which
were basically confined in
this room, were
getting quite hungry.
And towards the end of the experiments,
they actually had to import food from
outside of the system.
So it's not as easy to
rebuild such a nervous system.
And actually we can be happy that we are
living in such a stable one as we
have currently on the planet Earth.
Now, the last the third
option of reducing complexity
is we put the real
world into a set of equations,
a computer model, and
used this computer model to simulate
the Earth system.
Um.
There's a clear advantage of this,
first of all, it's quite cheap, so you
can repeat it, you can do several,
um, well, thousands of
of simulations.
And of course, in reality, we only have
one planet. Right. So we can only carry
out one experiment.
And that's the experiment we are
currently living in.
Um, so there's
no option to repeat it if we fucked
up the climate or something else.
Sorry. Um,
so this has been the first
computer model or the first widely
known computer model?
It's the world's three model from
1972, uh,
known by the report, The Limits
of Growth of the Club of Rome.
The basic message was that if you have
exponential growth of the population
and the exponential growth of the economy
while you have limited natural resources,
there will be one point where the
social system collapses, where the
population is going down up to
a level where the planet can sustain it
again.
Of course, this was one of
the first computer models, it was really
simple. It was also being
heavily criticized for being
oversimplified.
And luckily for us,
those projections didn't become true.
Um, but
it already shows by
triggering off quite a big debate
that it was quite a useful, um,
computer model because suddenly we were
thinking long periods forward
and, um, and of course,
we did not stop with this one
computer model, but we continuously
further developed it.
So this was 1972, 35,
more than 35 years
ago.
And, um, since then,
of course, computers became much
more powerful.
And, of course, also some
a bit slower technological progress
in the science community happened.
So we are still on the challenge
of making good, simplified
computer models. Of course, they are
wrong. That's what a model is always
because it's simplified.
It leaves out processes that are
important, but they are useful for us
for decision making.
So at Potsdam
Institute, we have quite an awesome
ensemble of different models,
um, uh, here you can see, for example,
climate models feeding information
to a vegetation model which calculates
carbon stocks, the natural vegetation
crop yields, uh, hydrology
and so on.
Then we have information
from suchan vegetation
model, uh, being handed over to
a land use and agriculture model, which
is the model called Magpie.
And then we also have a macroeconomic
model and energy model which stimulates
the development of the industry, of
the service sector, of the,
um, of the energy sector,
and, of course, also always the
greenhouse gas emissions.
I want to focus today on the
magpie model.
Magpie's stands for a model of
agricultural production and its impact on
the environment.
This is the model I'm working with.
It's developed by a large
group of approximately currently
15 people, um,
of various scientific backgrounds.
So we have economists, um,
we have physicists.
We have, um, uh,
um, uh, biologists,
geologists and so on.
And the basic question that we want
to answer, if our model is
how will the agrifood system look like in
the year 2050 and beyond?
Why is this important, probably
for you, agriculture is not so important.
Hardly anyone still works in agriculture.
But for our planet, agriculture is
really important. It's our main interface
with nature.
If you look at our planet, 30 percent
of the terrestrial surface is
covered by agriculture, either by
cropland or pastures.
Um, if you look at
greenhouse gas emissions, 25 percent
of the greenhouse gas emissions come
from land use, change and agriculture.
So, again, uh, struggling
with agriculture.
If you look at water, 70
percent of human water withdrawals are
for irrigation water.
If you look at water pollution, at
herbicides, it's biodiversity
always. There is, um,
agriculture as one of the major drivers.
Also, we are now really
changing the nutrient cycles
of the world, increasing,
for example, the nitrogen cycle
by a factor of three or four, um,
relatively two earlier years.
And there's also another thing, of
course, agriculture is also really
important for us humans, because we can
live without energy. We can't live
without food.
And if you look at
the global nineteen,
uh, leading risk factors
worldwide, um,
for preliminary death.
11 of them are connected somehow
to nutrition.
So either we eat too much,
which is rich or too little, which is
green.
Um, it's something like iron
deficiency, vitamin A deficiency,
suboptimal breastfeeding.
But on the other hand, there's
also a lot of things connected to
unhealthy diets like high blood pressure,
high blood glucose, overweight and
obesity.
On these top 19, you cannot
find wars or terrorism or something like
that.
But it's really about mostly about
chronic diseases.
And most of the chronic diseases are
strongly connected with our daily diets.
So how does such a model look
like basically we start
off with the food requirements,
what do people actually eat
and what what what do they actually
need as food to sustain their body
functions?
Well, this, of course, depends on
how large the population is and
what each of them eats.
At the moment, we are already at
a world population of seven point
six billion, um,
and we are still growing.
We will most likely be,
um, eight point five to 10
billion people in the year 2050.
So then we need to do some more
refreshments here.
Um, and
eventually afterwards, there is
an option that it might decline or
further increase.
And this depends a lot of
on education and on
family planning.
At the same time, what people
need to sustain their
body functions per capita is is quite,
uh, is quite,
quite always the same.
Actually, there are some differences
depending on demography.
You can see that Africa has a lower
requirement because there are a lot of
young kids are, uh, in
contrast, in China, a lot of, uh,
young adults, uh, you have
high food requirements.
But of course, this will shift as soon as
we have demographic change in the future.
And then we will have, in contrast, high
food requirements in Africa per capita.
But in general, the range is really low,
2000 to 2300 kilocalories
per capita per day in population
average.
But this is, of course, what the people
would require, what they actually
what they actually consume is much more
so you can see in Germany we have 3500
kilocalories.
In India, it's closer to the food
requirements of two thousand four hundred
fifty.
But you can also see not only that,
there's a lot of overconsumption.
You can also see that the diets are quite
different.
In Germany. We eat quite a lot of animal
products which people
in Nigeria or India don't,
and we actually don't
eat too much fruits and vegetables, which
is a shame for us.
Um, but.
Um, you
can see that we consume
about one third more than we need, and
what's the reason for this?
Basically, it's that we waste
most of our quite a substantial fraction
of our food.
About 30 percent of the food gets
wasted in households, um,
just because people, well,
don't care too much about it.
Um, and you can see
a quite strong correlation,
so as soon as, um,
people increase their living standards,
as soon as the Human Development Index
increases, you'll also see
that the food waste
is starting or the overconsumption.
This also includes, uh, overconsumption
in the sense that people eat more
calories, but also that the window is
quite narrow.
Most of it is food waste.
OK. And the same you can see for
per capita calories in
order to share of livestock products.
You can see that the share of livestock
products strongly increases
with income. On the left, you see just
a scatterplot between
income and livestock share
for all countries of the world for the
last 50 years.
And you can see that countries
strongly increase their meat consumption,
especially when they move from
very low incomes to medium incomes
for very high incomes.
Eventually, the livestock share declines
again.
And you see the same actually also for
processed foods like oil, sugar
consumption goes up.
Um, unfortunately, you don't
see it for fruits and vegetables, which
would be healthier, but they are, etc.
It's quite as an early income.
And then, of course, this food,
the food demand has
to be satisfied by production before
that, there's some trade.
International trade is increasing over
the last decades quite strongly, much
more than production.
And next to food demand,
there's also the demand for materials,
but also for bioenergy, which will play
a role, an increasing role.
I don't know if you heard the talk
before, which
may play an increasing role in the future
if we want to mitigate climate change
because bio bioenergy is one option to
take CO2 emissions again out of
the atmosphere.
Then Fuji's, of course, also processed
and here the livestock products really
play a huge role because
in order to feed one or
in order to produce one calorie of
livestock products, you need
multiple plant calories
to feed the animal.
At the moment, approximately half
of the proteins that are produced
worldwide on the crop lands
are fed to animals
and additionally, also
a large, even larger quantity
of of pasture, which is grazed
by animals.
And finally, we have
crops and these crops are standing
on a land, and here you can
see some land use dynamics.
Here you can see a projection or
scenario, a future scenario
of how
the cropland might expand
in the future.
Quite strong expansion, especially in the
tropical areas, because they are
also the population growth, this largest.
And next to land use,
this also, while
on the one hand you have cropland
expansion, but this is not the only
option, of course, to increase production
in the past is made up only 10 percent
of the increase of production.
The largest increase actually came always
from the intensification of the
existing areas.
And here you can see the
basically the crop yields that we would
need in the future in order to sustain
our, um, or
to fulfill the demand.
And finally, our model
also considers all the interactions with
the biochemical cycles.
So how do we change the nitrogen
and phosphorus cycle?
Also, how will water scarcity
change? This is a picture where you can
see the water scarcity in 2010
and 2050.
So it's basically not a water scarcity,
but how much of the water
that is available will be the use?
And, um, uh, the
nitrogen cycle is the third
most important, um, uh,
biochemical cycle of the world has
been changed tremendously by modern
agriculture.
We are now about five times the amount
of nitrogen which flows through the cycle
than in pre-industrial times.
And finally, we end up with emissions
and, uh, well,
if we assume a scenario where
we don't take action,
we can assume that or we
simulate that the emissions will further
increase.
While actually in order to keep
up or stay below the two
degree aim, we would actually need the
land use sector to sequester carbon.
So we need to take CO2 out of the
atmosphere. This is something that only
the land use sector can provide
at low costs, either through
afforestation, through plantation
of biomass or
through accumulation
of carbon in soils.
So this is the whole integrated
model, and the great thing is that, um,
uh, well, it's an
optimization model where everything
influences everything.
So if you put a carbon price in, this
will change the whole supply chain.
It will change the food demand.
It will change the global trade patterns.
It will change the land use pattern.
If you you can also see the interactions,
for example, between the nitrogen and the
water cycle or, um,
uh, how, um,
uh, well, and
but you can also see quite well the trade
offs that exist in our in our earth
system.
So if you only want to solve
one specific aim, it's still,
well, quite, quite easily possible.
Um, but as soon as you have multiple
goals, for example, if you want to
provide enough food for, uh, for the
whole world population, this will also
require you to increase your food
food production and
then you will have the environmental
impact.
If you want to reduce,
uh, greenhouse gas emissions, you
will need bioenergy.
And this, of course, also has negative
impacts, again, on biodiversity, on food
consumption, on food prices and so
on. So it's a very complex system.
And, um, it's
it's a really a challenge,
but it's possible, um, uh,
to transform our
society sustainably that we
actually meet all these goals at the same
time. What's really crucial there is,
on the one hand, the consumption side.
So we really need to reduce
food waste and we need to reduce the
consumption of animal products by
large scale.
So halving animal consumption,
having the food waste in Western society
would be something that we should aim
for. And this is really difficult.
Um, at the same time,
the whole production system can be much
more efficient.
A small price on on carbon
would be sufficient to trigger off
technical innovations probably and
to implement low cost carbon,
uh, mitigation technologies.
But these are probably the two things
that we need most.
We need
a policy that puts prices
on emissions, on carbon or nitrogen,
on water pollution,
and we need some kind of
policies that change the preferences
of the people in a way that they,
for example, education, school education
for what is a healthy diet.
How how do you cook at home?
And so on all day, all these
kind of projects have to be really
encouraged.
So what can you do?
Well, one advice I would
want to give out is get involved
in modeling.
Um, uh, most of us are actually,
um, uh, well, we
are we are not computer scientists,
uh, from the beginning, but we have to
learn quite a lot, all of this.
But we are rather coming from
disciplinary backgrounds, economists
or or biologists
or something like that.
And but most of our time is
actually software development.
And, um, it's not
that we don't want software developers,
it's just that few people actually
apply there.
So I think
putting up the standards of software
development in the whole field would
be really a great thing.
Um, the second thing is there's a lot
of data out, um, and
there's a lot of, um, uh,
well, also, uh, great
science that could be communicated,
um, uh, using good
visualization techniques, using
um also maybe artistic
projects and so on.
I just want to give you one example
before I come to the question and answer
here. In the last year, we made a,
uh, workshop with arts students,
uh, who developed interactive
installations using our data.
For example, here, it's an audio
installation where people could hear the
sound of different, um,
uh, scenarios, depending
on whether it's a, um,
a scenario where all the forests
are cut down and you have roday
agricultural sounds or more
urban sounds in another scenario.
Um, uh,
or, uh, maybe I just
pick one more because we have limited
time. This is, uh,
an artwork by a student
from Bangladesh and
um, uh, she created a climate box.
You can enter this climate box, throw in
a coin, and then, um,
using an arduino.
It's, uh, it all starts moving.
You get told the story of climate
change.
Um, but at the same time, also the
weather in the climate box is changing.
So suddenly it becomes hotter and there's
a fan blowing in hot air and,
uh, suddenly it starts raining and
there's flashlights and,
uh, and then if you don't spend
more money on it, um, uh,
then it becomes even worse and worse and
worse.
So.
This artwork was actually inspired
because she said, well, people
back home, they see climate
change as something abstract, but
as long as they don't feel that they will
do something. So she came up with this
idea, OK, now
I'm ready for a question.
Answer. Thank you very much.
Everybody with questions, please go to
the microphones in the
room and Internet
over the signal.
So microphone one, please.
It's just I got an electric chair.
Thanks for the Talk Back question.
When you looked at the needs of people,
you spoke about calorie requirements.
However, nutrition is much more than
calories and especially and not
not in Germany, but in
Zaal area, when you further reduce
the animal protein part,
you get problems with malnutrition.
Is that something you factor in or just
plain calories and you
eat sorghum or sorghum?
No, of course.
Um, dietary dietary diversity
is really important.
Um, I would not say that the animal
protein is the only way of of
of, uh, solving this,
uh, because, um, uh, you
can have a, uh, a balanced
diet also without animal protein.
But it's important. Actually, one of the
most important challenges is to drive up
the consumption of vegetables and fruits,
um, by by
by several factors.
Um, and there's hardly
any, um, positive
limitation to the, uh,
the especially for
vegetables, to the health impacts
of, um, higher consumption
of vegetables and fruits.
Of course, we look at the dietary
composition and um,
there we also don't only look at at,
uh, livestock versus plant calories,
but also now on fruits and vegetables
and unprocessed calories.
Um, but
yeah, of course, I think it's, uh,
it's a major problem that
we should not play out goals
like food security against
goals like climate change.
We need to simply tackle both of them
and as urgently as possible.
Um, uh.
Yeah.
I think we have five minutes,
so next, microphone number
two, please.
Sorry, I think I'm too small for this
one.
OK, um, so I've got two
questions.
Uh, you were talking about trade offs.
So what would you think
is the best solution
to the crucial trade off between,
um, biodiversity
and land conversion for food security?
The second question is, you were talking
about how important it is that
we invest in societies, drive
up our vegetable and fruit consumption,
but this again would mean that
we shift the land usage
for high calorie
foods, even if they are not
dairy or, well, livestock
in any way.
Um, so that, again, we use
more land and this again
would cause more.
Well, rivalry between
global food users.
Um, isn't this contradictory
to food security and aren't
we quite healthy already
if we stopped eating sugar like crazy.
Thank you. OK, ok.
Um from
uh I forgot the first question again.
What was the first question.
Um, uh,
biodiversity.
Yeah. So, uh, there's certainly
a um uh a trade off between
those two. But as I said before,
um, uh, in the past, only
10 percent of the cropland
in the last 50 years only increased by
approximately 10, 11 percent.
And all the rest of the productivity
improvements were actually reached
on, uh, on the area.
At the moment, they are quite large yield
gaps in wide, wide areas
of the world where you could actually
intensify, um, uh,
and where it would be actually good to
intensify the systems, um,
uh, to a certain degree and
without any land expansion actually
necessary.
There are certain areas where, I guess
land expansion is possible.
Um, it's always a trade off, of course.
Um, uh, and we are trying
to build in exactly this trade off by
now, including biodiversity
indicators in our model.
But this is still a work in progress.
Uh, to the second question on the fruits
and vegetables, fruits and vegetables
actually make up only a tiny share of
current land use.
Um, I think less than, uh, less than 10
percent, definitely.
Um, and at
the same time, uh, they
are producing quite high yields because,
uh, it's not the land,
which is the, uh, the the main resource
there, but it's labor which goes in
and, uh, capital.
It's not necessarily a clean production
either, because you have large nutrient
runoff, often large pesticide use.
But in terms of land use, it's not such a
bad thing.
You get quite high, um,
uh, tons of,
um, uh, product produce out of a
vegetable farm.
Um, but of course, there are also
trade offs here. There's a sustainable
probably if sugar is providing
really cheap calories, um,
uh, without large environmental
footprint, if you calculated per calorie.
In contrast, fruits and vegetables
provides very little calories but provide
a very nutritious food
in terms of fiber, vitamins and so on,
we have a lot of question.
I see aid and one from the Internet.
Uh, I we have just two minutes, so
I take one from the Internet, one from
five, and I ask everybody else
to ask the speaker afterwards.
Yeah, he is here.
And he answered all your questions.
So Internet. What is your question.
OK, so
the ACA asks, how do
I get involved in modeling?
Can I play with Magpie by downloading
code and data somewhere
along the Internet?
Um, uh, the
the model will become open source next
year. So we are currently, um,
in the process of the whole
legal stuff of making it open source.
Um, so the next model version of
our model will be published.
Open source.
Microphone five, please.
Hi, thanks for the great talk.
Yes, last year there was also some talk
about food plant
based food innovation that that
is science based.
So my question is twofold.
First, do you implement technological
innovation that would lead to a more
plant based diet
and in general in the model
and the second one, how hopeful are you
personally that those will having
an important impact in the future?
You're speaking now of some kind of, um,
plant based meat
replacement products and so on?
Um, yes.
We we we actually published
a study or a commentary
this year also on, um,
a quite extreme case of this, which is
basically landless food production.
So you can breed microbes
based on fertilizer
and energy, um,
which is a kind of a space
food technology which was developed by
the Russians. But now it actually becomes
commercial, um, uh,
commercially cheap.
Um, uh, I guess it will certainly
happen for certain, uh,
protein foods.
So it will, for example, replace,
um, uh, soybean or
fishmeal in animal feeding
to a certain proportion.
Um, I'm not so sure about,
uh, the actual nutritional
value of this, um,
or about.
Well, I'm a bit skeptical how how
positive I would judge it, but I would
judge it quite realistic
also for the whole meat replacement
product based on on plant based,
um, uh uh,
on plant basis, I think it will become
economically cheaper.
And then you will have a tipping
point where simply because
of economic reason, it's cheaper, people
will reduce their meat consumption, or
for example, a burger will consist of
half fake meat and half real
meat because it's cheaper.
And, um, I think this transformation
will happen. And somehow the breeding
animals just for
for for their meat seems
the technology, which is somehow outdated
for the 21st century, if you ask me.
Then give more than a big
applause to Dr.
Benjamin Leon.
Thank you.