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00:00

we need to meet a new constraint and
that constraint has to do with co2 co2
is warming the planet and the equation
on co2 is actually a very
straightforward one if you sum up the
co2 that gets emitted that leads to a
temperature increase and that
temperature increase leads to some very
negative effects the effects on the
weather perhaps worse the indirect
effects in that the natural ecosystems

00:33

can't adjust to these rapid changes and
so you get ecosystem collapses now the
exact amount of how you map from a
certain increase in of co2 to what
temperature will be and where the
positive feedbacks are there's some
uncertainty there but not very much and
there's certainly uncertainty about how
bad those effects will be but they will
be extremely bad I asked the top
scientists in the several times do we
really have to get down to near zero
can't we just you know cut it in half or

01:03

a quarter and the answer is that until
we get near to zero the temperature will
continue to rise and so that's that's a
big challenge it's very different than
saying you know we're a 12-foot high
truck trying to get under a 10 foot
bridge and we can just sort of squeeze
under this is something that has to get
to zero now we put out a lot of carbon
dioxide every year over 26 billion tons
for each American it's about 20 tons for

01:34

people in poor countries it's less than
1 tonne it's an average about 5 tons for
everyone on the planet and somehow we
have to make changes that will bring
that down to zero it's been constantly
going up it's only various economic
changes that have even flattened it at
all so we have to go from rapidly rising
to falling and falling all the way to
zero this equation has four factors a
little bit of multiplication so you've
got a thing on the Left co2 that you

02:05

want to get to zero and that's going to
be based on the number of people the
services each person's using on average
the energy on average for each service
and the co2 being put out a per unit of
energy so let's look at each one of
these and see how we can get this down
to zero probably one of these numbers is
going to have to get pretty near to zero
now that's back from a high school
algebra but let's let's take a look
first we've got population the world

02:37

today has 6.8 billion people that's
headed up to about 9 billion now if we
do a really great job on new vaccines
health care reproductive health services
we could lower that by perhaps 10 or 15
percent but there we see an increase of
about 1.3 the second factor is the
services we use this encompasses

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