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>> Welcome, everyone.
Thank you for coming on this lovely autumn day.
I'm going to talk about population growth, development,
climate change and human health, some of the big challenges
that we face this century.
I'm going to take a historical view of how they are linked
and what this might mean for the future.
But first, a short video clip from the opening ceremony
of the Olympics last year
about the Industrial Revolution where it all...
[ Music ]
>> Rising dramatically from the ground, the smoking stacks
and the chimneys that give [inaudible]
but it disfigured many thousands of these
and transformed society.
It's definitely my kind of history that's in here.
It's such a sound.
It's so powerful to look at the Industrial Revolution this way
but if you're at home watching on TV
and you've got the remote control, just turn it
up a little bit and you'll get a sense
of what we're feeling here in the stadium.
[ Music ]
>> Okay so, how many of you saw that last year?
How many of you saw that ceremony?
Were some of you actually in the stadium?
Oh, lucky you!
I thought it was fantastic.
So as the commentator said in that clip,
the Industrial Revolution brought great wealth
but also disfigured towns and cities.
And these illustrations -- oops -- from the time showed the kind
of squalid housing that the new factory workers lived in.
And these appalling conditions of overcrowding that led
to frequent disease outbreaks of cholera and so on.
So eventually that led to steps to improve health at the time
and that was really the start of public health as we know it.
I think the Industrial Revolution wouldn't have got
very far without some improvement in those conditions.
So the next slides, I've just summarized some
of those key developments on public health
like the sanitary idea.
So in 1842, Chadwick, Ernest Chadwick reported
on the sanitary conditions of the laboring population
of Great Britain and he showed
that life expectancy was much lower in towns
than in the countryside.
Not very surprising when you see those pictures
or you read Dickens.
1848 was the first Public Health Act which empowered local boards
to deal with environmental rubbish and cesspools
and faulty drains and so on.
And then in 1858, we had what was called the Great Stink
when literally the stench from the Thames was so appalling
that Parliament stopped meeting.
And that clearly had to have some remedy
and Joseph Bazalgette who was the Chief Engineer
of the London Metropolitan Board started building a network
of London sewers which are still in use today.
It was this kind of improvements that led to a big impact
on human health event though many of the key figures
in the sanitary movement believed
that diseases were caused
by breathing foul air rather than by infection.
That mistake didn't really matter in the sense
that the end result of cleaning
up the environment had this big effect on health.
And here you can see this figure shows death rate
from TB dropping very steeply long before the cause
of TB was identified or before any treatment was available.
And then there were a series of Factories Acts which tried
to improve health and safety
and there was compulsory immunization for smallpox.
And the combination of these public health improvements
reduced death rates
and triggered a global demographic transition
which is shown in this stylized diagram.
So what is the demographic transition?
Well essentially, it describes how a population
with high birth rates and high death rates ends
up having low birth rates and low death rates
and in the process becomes much, much larger.
So before the transition starts in this phase,
population is fairly stable because on average,
only two children survived to adulthood to have children
and then only two of their children survived
to have children and so on.
So the population stays pretty steady.
But as the death rate starts to fall, the population grows
and -- I'm sorry, oh, that's all right --
population grows and eventually that leads people
to decide they want to have smaller families.
And so then you get a fall in the birth rate
and eventually you end up with this situation
of low birth rates and low death rates
but the population is much bigger.
Note back as the fertility rate has already come down,
population growth is still increasing and that's
because the improvements
in survival a few years earlier mean
that there are many more young people having children.
And this bit at the bottom here shows what happens
to the age structure of the population
through this [inaudible] of transition.
So the blue is boys conventionally
and the pink is girls.
And to begin with, you have this pyramid-shaped structure
with lots of young children but because survival is poor,
there are very few elderly.
And then as you get this fall in death rates, more people survive
and you get a big bulge here in the adult population,
the working age population relative
to old people or children.
And then as the fertility rate comes down,
this means there are fewer children
and you get an older population, the proportion
of old people increases.
And this is the situation you arrive at which is
where we are now in developed countries
where the transition first started and it took
about two-and-a-half centuries to unfold.
In other countries where the transition started
in the last century, the pace has been much faster
but it's still unfolding today.
And how precisely unfolds the timing of these events
and the lag between the fall in the death rate and birth rate
and so on, that is very variable and it depends
on external conditions like education and family planning,
things which would accelerate the fall in birth rates
and that varies very much by region.
But the fundamental processes here are the same wherever the
demographic transition occurs.
So that's fall in death rate, growth in population
and then later on, a fall in the fertility rates
and aging of the population.
You're not going to get tested
on this before you leave the lecture later,
but I think it's useful to have those thought processes in mind.
Okay and the next slide shows how much the population has
increased since the Industrial Revolution
and how much more it might increase in the future.
So at the beginning, you've got this stable population
and then there's this huge increase in growth
in the last century with just over seven billion now
and it only took 12 years for the population to increase
from six billion in 1998 to seven billion in 2012.
Now these three curves that projects into the future,
they are based on UN projections about according
to different demographic scenarios.
So the medium projection, this blue one which is regarded
as the most likely assumes fertility rates will continue
to fall in this century like they did in the last century.
And it would bring us to a population of about nine
or ten million during this century
and then it would plateau.
The difference between this high variant
and the medium variant is just half birth per woman.
So the global fertility rate gives the --
which is based on the average rate for all women --
if it's just one-half a birth higher then you get a much
bigger increase in population.
And the difference between these two curves again is
just half-a-birth.
So you can see that the birth rate fell from an average
of five births per woman in 1950
into two-and-a-half births per woman in 2005.
So that half-a-birth difference in this century is going
to have a huge impact on final population size.
And of course, it's not just -- well, sorry --
that shows the global picture and it hides a huge amount
of regional variation
so virtually all this future growth is going to be
in developing countries.
In developed countries as we've seen
where the transition is completed,
the population is stable, leaving aside migration.
And it's not just the population that's been increasing,
this slide shows growth in all kinds of activity
since the Industrial Revolution.
So this is population.
Here, we've got water use.
This is motor vehicles, telephones, and increase
in McDonald's restaurants [laughter].
So the general picture, you can see more people,
more complex societies and more consumption.
Okay and it's not just those things of course warming
up the climate is something that's placed with as well.
This one shows increasing global temperature on this axis here.
Now this slide looks very complicated
and I believe it is very complicated.
These are, again, projections as to what might happen
in the future and these come
from the Intergovernmental Panel on Climate Change.
And they're based on different scenarios like I showed
in the previous graph.
Now the IPCC which is a group of 500 or more scientists
who come together and try and work out what's happening
to the planet system, they just produced their fifth report very
recently which some of you may have seen the headlines
in the papers.
And the conclusions are quite blunt.
The warming of the climate system is unequivocal
and it is down to us.
Human influence in the climate system is clear.
Just a few more of the headlines here from that report.
The atmosphere and ocean have warmed.
Snow and ice have diminished.
Sea levels have risen and greenhouse gases have increased.
The concentration of carbon dioxide has increased by 40%
since pre-industrial times primarily
from fossil fuel emissions.
The ocean has absorbed about 30%
of carbon dioxide causing ocean acidification.
And the various scenarios that I showed you in that slide,
they all indicate further warming this century and beyond.
So again, that global picture hides huge regional variations.
So this slide brings together several things.
It's a bit complicated.
So this column is cumulative emissions
since the Industrial Revolution, since 1750.
This column is emissions in one year, 2004 and this is growth
in emissions in a short period of 2000 to 2004.
And this is the population.
So you can see, it's been split up into four big emitters,
the big individual countries, USA, Japan, China and India.
And then groups of countries that --
this is the former Soviet Union, this is the EU,
D1 is the other developed nations,
D3 are the least developed nations and D2 in between.
And what you can see is that the developed nations so orange,
red, yellow and green, these have contributed most
to cumulative emissions but much less to recent growth emissions.
And it's because [inaudible]
for developing countries particularly
because of China here with its huge growth in recent emissions.
I think the other thing to say is
that these least-developed countries have had virtually no
contribution to planet change whatsoever.
There's barely a black line up here but these are the countries
where population is growing fastest and where the need
to reduce poverty is greatest.
And to date, the model for economic development
and bringing people out of poverty is based
on industrialization, fossil fuel consumption
which releases tons of carbon dioxide into the atmosphere
and messes up the planet system.
So it's a real conundrum and brings
in this whole notion of climate justice.
What's worse, I think, is that these least-developed countries
which have not caused climate change are likely
to be worse affected by the consequences.
So this slide shows a map of Bangladesh
which is a poor country.
It's densely populated and it's already heavily prone
to disastrous flooding.
And this slide shows what happens
if the sea level rises one meter.
A huge area, home to hundreds of millions
of people just gets submerged.
So the next few slides I'm going to show you are
about how people have responded to all these observations.
Concern about population rate of growth is certainly not new.
The Reverend Thomas Malthus in 1798 wrote this famous Essay
on the Principle of Population and he argued that growth
in population would always outstrip food production.
The only way to keep the two things in check was
through natural disaster or as he put it, in misery and vice.
He was after all the Reverend Malthus.
Then in the 1960's and 70's, two books that had a big impact
on environmental awareness
and on public policy were the Population Time Bomb, sorry,
The Population Bomb by Paul Ehrlich and Limits To Growth
from the Club of Rome thinktank.
The Population Bomb opens with the effort of feed all
of humanity, the battle to feed all of humanity is lost.
Hundreds of millions of people are going to die of starvation
in the 1970's and nothing we can do now will stop that.
So I don't know why this keeps getting by themselves.
The Limits to Growth was less sensational in style
but it also predicted disastrous collapse
of environmental systems due to population growth.
So not surprisingly, there was a surge of environmental activism
around this time when the Friends of the Earth emerged
and Greenpeace and I think these beautiful photos of the Earth
from space had something to do
with people's increased awareness of the environment.
And that really contrasted with all the news at the time
about huge oil tankers leaking oil
and nuclear disasters and so on.
In 1985, the British Antarctica survey discovered a hole
in the ozone layer which actually you all remember.
And that led to a period of environmental diplomacy
with various agreements being signed.
And concerns about global warming started to surface
at that time as well and the IPPC, oh IPCC sorry,
was first established in 1998.
And I think climate scientists and skeptics
and activists have been locked
in some pretty fierce controversies since then arguing
about whether climate change is real,
and whether it's really due
to human activity or natural causes.
And although that sort of debate hasn't disappeared,
it's quite clear that the scientists who worked
on climate change are sure that it's real
and it's really down to humans.
The Earth Summit in 1992 was an important event.
It led to a couple of UN conventions,
the Convention Framework on Climate Change
and the Convention on Biodiversity.
It also put population, reducing poverty, the role of women
and health as core to sustainable development.
So what do we mean by sustainable development?
Well, I'm sure some of you could give a whole lunchtime lecture
on what that means but essentially,
it's about being able to meet the needs
of the current generation without compromising the ability
of future generations to meet their needs.
All these principles have recently been reiterated
in the Rio Plus 20 Summit last year.
So another debate has been going
on particularly amongst columnists.
It's about relationship between population growth
and economic growth.
Is it bad for economic growth to have more people?
I've sort of summarized about half-a-century of debate here
to three bullet points.
So the early studies suggested there was a negative association
between population and economic growth.
And then the so-called revisionist views rather
downplayed the effect of population
and more recent studies have confirmed the adverse economic
effects of rapid population growth.
So you might ask why is it that it seems the experts can't make
up their mind on this?
Well, I'm not an economist, as you've probably guessed,
but I think part of the answer is that to begin with,
they didn't have enough good data, long-term perspective data
to allow one to stand back and look at the big picture.
And I think another reason is that economic growth
after the Second World War was so rapid that the effects
of population growth were kind of swamped to the mist.
And so once economic growth slowed down, the adverse effect
of population growth became more apparent.
And this rather faint graph here,
I've taken from Tim Dyson's excellent book
on Population and Development.
And you can see here, this is growth in population.
This is -- oh, I'm sorry.
This is growth in economy
and you can see the negative relationship here.
These two countries are Korea and China and down here,
we've got Democratic Republic of Congo and Madagascar.
Okay, so one obvious way to influence population growth is
through family planning.
And this slide shows the changing fortunes
of family planning.
It didn't start very well.
In 1916, Margaret Sanger was arrested
for opening the first birth control clinic in New York
and Marie Stopes who opened the first birth clinic in London,
near here; she had a pretty tough time
from the establishment too.
Doctors wanted nothing to do with contraception.
It was regarded as rather unsavory.
In fact, family planning service didn't [inaudible] the NHS
until 1974.
But for the women who came flocking to these clinics,
it was a very different matter.
They were desperate to have the means of for them to
yet another unwanted pregnancy or abortion.
1960's was when the pill and the IUD became widely available.
This was the era of modern contraception.
And of course, the pill transformed women's lives along
with free love and peace and women's liberation and so on.
And unlike the opposition to contraception in US and Britain,
in developing countries faced
with these huge growing populations,
governments promoted family planning very strongly.
And some programs were popular
and successful like in Bangladesh.
Others were inept or coercive.
And things like China's one-child policy
and intensive sterilization in India created a backlash
that set the tone for this important meeting in Cairo.
This was very different in Cairo.
It was about a human rights approach.
It was about the concept of *** health and the right
to have a safe and satisfying sex life.
However, the message of Cairo faltered really and the fortunes
of family planning sank literally as funding fell
by more than a third over this period despite full
population growth.
Why did funding fall?
Well, there are lots of reasons but the politics
of abortion overshadowed discussion of family planning,
opposition from the Catholic Church was still strong,
and money was diverted to the *** epidemic.
And a low point, a particularly low point was
when family planning was altogether missing
from the Millennium Development Goals on [inaudible].
Nonetheless, global fertility [inaudible] was halved.
It was about five births per woman in 1950
and two-and-a-half by 2005.
And fortunately, there's been a big upswing
in the fortunes of family planning.
So last year, we had the London Family Planning Summit
and world leaders and the Gates Foundation and so
on raised the profile of family planning and talked
about the benefits of it.
Extensive benefits so we know
that through preventing unintended pregnancies
and unsafe abortions,
contraception has already reduced maternal mortality
by 40%.
40% and could prevent 70% of all maternal deaths, if all women
who needed family planning had access to it.
Women use family planning
to space their births further apart instead
of having them one straight after the other.
Child health and survival improves.
And women's health improves as well.
There's fewer children to take care of.
The children get more of the available resources.
Women are freed up for employment
and economic benefits derive from that as well.
So family planning leads to early benefits
for maternal and child health.
It changes the social and economic position of women
and it brings long-term economic benefits as well.
Okay, at the start of this century,
I did mention the Millennium Development Goals.
This really set the agenda until 2015
which actually is not very far away.
This was about reducing poverty.
It was about primary education; promoting gender equality;
improving child health and maternal health;
reducing malaria, ***, other diseases.
It was about environmental sustainability
and global partnerships.
And as I said, family planning, although it impacts
on virtually all of these goals, it didn't actually appear
until 2007 when this goal was added, universal access
to reproductive health.
The Millennium Development Goals have undoubtedly been a powerful
focus for global development and much has been achieved.
So some of the headlines here, child death rates have fallen
by 40% and there's been lots of achievement in malaria
in particular and other infectious diseases.
But not all the MDG's will be met by 2015 and things
like maternal mortality and education lag behind.
But of course, it's really hard to keep up with the pace
of change because there are now one billion more people
than there were in 2000.
So you better kind of keep running fast just to keep up.
And for example, things have changed so much,
there were now six billion mobile phone subscriptions
compared with one billion when the MDG started.
We can say that overall, people are healthier,
wealthier and better educated.
But the poorest 1.2 billion account for only 1%
of consumption and the richest billion consume 72%.
So there are still these [inaudible] in equality.
The main causes of death have changed
because the world has gotten older, as I was showing before,
and so disease burden is much more about chronic diseases
like heart disease and cancer and obesity rather
than infectious diseases.
So how has UCL responded to this?
Well, I was one of many colleagues who got involved
in the UCL-Lancet Commission on Climate Change a few years back
and at that time, climate change was all
about the physical effects and the Stern report
on the economic effects was quite new then
and Al Gore's film An Inconvenient Truth and so on.
But we felt that the health impacts have been a
bit neglected.
So we have this commission and during that time, we also felt
that population had been a bit neglected
in the climate change debates.
So after that, we got funding from Leverhulme to set
up this symposium and put a lot of people together
to debate these issues.
And that gave rise to a paper which we published
in The Lancet early this year
which is really the basis of this talk.
And in that paper, we plot some of these events on a timeline.
I know this is not to be read
but green is the population events, red has to do
with development, and blue climate change.
And it includes many of the things
that I've been mentioning so far.
So to return to the title and somewhat in the last couple
of slides, global growth versus human health,
finding the balance comes up as sort
of a picture of a weighing scale.
It's clearly not like that.
In this diagram, I've tried to capture some of the complexities
and also the certainties involved.
So we have often at the center here,
in the driving seat is the demographic transition
and the fundamental forces that have shaped and continue
to shape modern society.
The engine of the transition is switched on intellectually
by the Age of Enlightenment and literally
through the Industrial Revolution which make possible
and necessary the changes in public health and improvement
in survival which then triggers,
it sets the transition in motion.
Consumption of fossil fuels and environmental resources leads
to great economic growth but it also causes climate change.
And the transition itself leads to huge population growth.
Global fertility is continuing to fall but in countries
where it's still high like in principally Africa,
the rate of fall of fertility is going to have a huge effect
on final population size
and whether those countries can meet the MDG's
and bring people out of poverty.
What the effect of that fall of fertility will be
on carbon emissions is less clear because it's not simply
about the number of people.
Its consumers, of course, climate change
and all of the people.
So factors like population, aging, urbanization and so
on will also have an effect and we don't know very much
about what those individual net impacts are.
The little bit of research that has been done suggest
that providing family planning to all women would lead
to substantial reduction in carbon emissions.
And how this whole transition plays out is affected
by these kind of positive factors, education,
family planning, employment systems and so
on which were largely responsible
for the Asian tiger economies developing so well
in their part of transition.
There are huge implications for the aging population
on human health and demand for healthcare
and social [inaudible] and so on.
But also, we know that this climate change
and thus biodiversity is continuing.
And if that's couple with water shortages
and food insecurity then there is the real possibility
of bleak Malthusian-like scenarios where more
and more people cannot have their basic needs met.
So what can we do about this?
In two slides, well, it seems to me that we need a second Age
of Enlightenment that would guide us in different ways
to think about how we deal with all this.
There's no shortage of organizations, declarations
and so on urging us what to do
and they mainly now reinforce message about the need
to reduce both consumption and population growth.
It's not either or.
Because of all these interconnections,
bringing people together from different disciplines
and communities and so
on to find solutions seems -- it makes sense.
It seems an obvious thing to do.
And I just put a couple of examples here.
So population, health and environment,
the so-called PHE projects, these aim to improve health
and wellbeing of local populations while also
preserving the critical ecosystems on which they depend.
So for example, marine conservation projects coupled
with family planning and so on in Madagascar and Philippines
and Bangladesh have been very successful.
Also, the benefits of health
for reducing carbon emissions are substantial
so it's another win-win here.
Walking and cycling reduces obesity, heart disease
and improves mental health and stops --
it gets people out of cars so that's good.
Clean burning stoves reduce air pollutants
by more efficient combustion and that reduces the exposure
to infections particularly in children.
And I'm referring here to some work from colleagues,
the London School of Hygiene and Tropical Medicine who tried
to quantify these effects, this sort of win-win effects.
It's clear that natural and social scientists need
to intensify research on the interactions
between consumption, demographic change,
and environmental impact.
So those things like aging
and urbanization how [inaudible] affect carbon dioxide emissions.
And I refer here to this really excellent, very expert,
very readable report from the Royal Society called People
and the Planet.
There are some encouraging signs.
Recently, the UN General Assembly agreed
to bring together these two frameworks
for the Millennium Development Goals
and the Sustainable Development Goals which had been running
on parallel tracks rather strangely.
So bringing them together around poverty alleviation
and environmental sustainability makes a lot of sense.
Possibly, with the next meeting of COP, the Convention
of the Parties in December 2015,
if that could achieve the same kind of merger
around carbon emissions because that's
where the negotiations are made
about reducing carbon emissions then we might get a more
politically and scientifically integrated view on the future
of the health of the planet.
Okay, so for those of you who like a sort of short slogan
or take home message, I wouldn't recommend this one.
Please don't try this at home [laughter].
The placard said, "Save the planet, kill yourself."
I think this one which says, "Change the politics,
not the climate," gets closer to the heart
of how we choose to live our lives.
Thank you.
[ Applause ]
>> Judith, thank you very much
for a fascinating, fascinating talk.
It's my job now just to chair about five minutes of questions
and answers, if anybody has any questions from the audience.
There are microphones coming
down so just bear with us for a second.
>> This is about who -- this is
about who the connection seems...
[ Inaudible Audience Question ]
>> I don't think we need --
don't need people for developed economy
and maybe the only employable people are going to be those
who can program computers to program other computers.
>> You're pretty [inaudible] of that.
Did the people hear that question?
No. It was -- so what do I do?
It was about -- the question was about the problem of employment
for much greater numbers of working age people in the...
>> Especially in light of the [inaudible] starvation.
>> Yeah. I think you're absolutely right and I think
that is certainly some major part
of the sustainable development agenda is how we manage
to find -- how we try and get employment
for those increasing numbers of working age population which,
if we can get that right,
as you saw in the Asian tiger economies so-called,
the benefit is from that big increase in young adults.
>> You can [inaudible].
>> And at the same time as also causing a lot
more industrialization.
So it's about finding ways that decouple those two.
And you're right, it's one of the big challenges.
>> I'm just saying you can have an expanding economy
without an expanding labor force.
So no one's going to care about the tens of millions of very,
very angry young men who have nothing
to do except wave AK-47's.
>> Okay, thank you.
Perhaps we could take another question?
>> Where do the ideas of James Lovelock fit in with you?
And I'm thinking particularly he said something
like sustainable development is a sham and we actually need
to contrite rather than go
for sustainable development and growth.
>> Well, the contracting converge concept,
I'm now thinking about is -- that is there in the messages
about reducing consumption
and population growth at the same time.
And if the imperative is to get -- to bring more --
a billion of the poorest people
out of poverty then the imperative forces the richer
countries to reduce their consumption
until there's some kind of contracted convergent match.
Yeah, I think that's correct.
That's the implicit message.
>> Are there any alternatives other
than genetically engineering new types of food that would deal
with an increase need for food?
>> My understanding is that we are capable
of producing enough food to feed 11 billion people or more
but that would be in a very different kind of world
that if we were doing that, then we wouldn't have [inaudible]
to maintain the kind of lifestyle that had been --
that we have in the west.
So it is very much about this sort of make decisions
about how we choose to live our lives and what kind
of environment we want to live in.
But simply food production, I think,
is not the key limiting factor.
>> Time for one more question?
>> [Inaudible] and sometimes Malaysia and sometimes I have
to wear a mask, I think [laughter].
>> She goes to the International School in Kuala Lumpur
and while we walk to school to save on pollution, often she has
to wear a mask and she wanted to share that.
>> Oh okay.
Thank you for that.
Yes.
>> Okay.
>> I'm going out.
>> Our time is done, I think.
It just remains for me to once again thank Judith
for her fascinating talk and to ask you
to thank her in the normal way.
[ Applause ]