I do not buy much of this because
it misses the major point that our technology will make longetivity the new
norm long before 2050. This will then
lead to a shift of human resources back to the land and a natural
deurbanisation that takes the services of the city back to the farm. It is already beginning to happen although
the momentum is still the other way.
Africa is about to sprint into
the modern world and birth rates are already dropping and the population should
ultimately match that of India
and China .
After that human expansion is
likely to be much more benign and aimed at optimizing water sheds globally
while allowing the natural world to fully adjust.
Recall that the long history of
land tenure everywhere has seriously created large inefficiencies everywhere. Connecting green belts, building effective
boundaries and optimizing crop production will take decades throughout the
globe. In that emergent environment,
natural wild populations will also have to be optimized and clearly managed. They are already steadily recovering because
the pressure of hunting is steadily subsiding.
By Natalie Wolchover | LiveScience.com – Thu,
20 Oct, 2011
In terms of evolution, the species Homo sapiens is extremely
successful. The populations of other species that are positioned similar to us
on the food chain tend to max out at about 20 million. We, by contrast, took
just 120,000 years to achieve our first billion members, and then needed only
another 206 years to add 6 billion more. According to the United Nations
Population Division, our population will hit 7 billion on Oct. 31, and though
fertility rates have begun to decline across much of the globe, we're still
projected to reach 9 billion by mid-century and level off at around 10 billion
by 2100.
A panel of academics met at Columbia University's Earth Institute on
Monday (Oct. 17) to discuss the impacts of the human population explosion,
including the ways in which it will change the face of the Earth this century.
Here are five
striking changes you — or your kids or grandkids — can expect to see.
Shifting people
Currently, it's a well-known fact that China
is the most populous country in the world, and that Africa ,
though riddled with problems, is not necessarily overpopulated considering its
size. These facts will drastically change. China 's one-child policy has
significantly curbed its growth, while in some African countries, the average
woman gives birth to more than 7 children. [How
Many People Can Earth Support?]
According to Joel Cohen, a population biologist at Columbia University
and the keynote speaker at Monday's conference, India 's
population will overtake China 's
around 2020, and sub-Saharan Africa's will overtake India 's by 2040. Furthermore,
"In 1950, there were three times as many Europeans as sub-Saharan
Africans. By 2100, there will be five sub-Saharan Africans for every European.
That's a 15-fold change in the ratio," Cohen said. "Could you imagine
that that might have an impact, geopolitically and on international
migration?"
Jean-Marie Guehenno, former UN Under-Secretary General for Peacekeeping
Operations and director of the Center for International Conflict Resolution at
Columbia University's School of International and Public Affairs, said the
migration of people from Africa to Europe will present a major challenge in the
near future. "You can look at it as an enormous potential from a European
standpoint … or you can say, '[Africa ] is a
continent that still has 15 percent that are not going to school,' and that can
be seen as a threat," Guehenno said. "How are you going to manage
that immigration so that this aging continent of Europe
benefits from it while managing it? That is going to be a huge question."
Urbanization
Globally, the number of people living in urban areas matched and then
overtook the number of rural people sometime in the past two years. The trend
will continue. According to Cohen, the number of people
living in cities will climb from 3.5 billion today to 6.3 billion by
2050. This rate of urbanization is equivalent to "the construction of a
city of a million people every five days from now for the next 40 years,"
he said.
Of course, new cities don't tend to get constructed; instead, cities
that already exist tend to balloon. Guehenno argues that megacities become
chaotic. "Urbanization is going to change the face of conflict in a big
way. When you live in small towns and rural areas, there are all sorts of
traditional conflict- resolution mechanisms. They are not all nice, but they
create a sort of stable equilibrium," he said. "With the megacities
that you see now in Africa, such as Monrovia (Liberia ) and Kinshasa
(Republic of Congo ), we see cities where the dynamics
are no more under control or have been lost. We are, I think, heading toward
new types of conflicts — urban conflicts — and we haven't really thought
through the implications of that."
Water wars
Not only has the human population exploded in the past two centuries,
but the per-person consumption of resources — especially in industrialized
nations — has grown exponentially. Scientists think that resource shortages
will cause an escalation of conflicts during this century, and will widen the
gulf between the rich and the poor — the haves and the have-nots.
No resource is more precious and vital than water,
and, according to economist Jeffrey Sachs, director of the Earth Institute at
Columbia, there are already parts of the world that, because of the rapidly
changing climate, are at a severe crisis point. "Take the Horn of Africa
for example: Somalia 's
population has risen roughly fivefold since the middle of the 20th
century," Sachs said. "Precipitation is down roughly 25 percent over
the last quarter century. There's a devastating famine under way right now
after two years of complete failure of rains, and [there is] the potential that
this is entering a period of long-term climate change."
Conflicts over water shortages will probably play out as class warfare,
said Upmanu Lall, director of the Columbia
Water Center .
"Wealth inequality tends to grow as a country's population grows, and this
is a very important point to note because per capita consumption of resources
has been increasing dramatically. Couple that with inequity in income and
couple that with [the issue of] the availability of water," Lall said. [How
Much Water Is On Earth?]
When you add it all up, you get this dire picture: As the population
grows, there is less water per person. Meanwhile, the gap
between the rich and the poor widens, and the rich demand more resources to
accommodate their lifestyles. Inevitably, they will commandeer the water and
other resources of the poor. In all likelihood, Lall said, this will lead to
challenges, and perhaps class conflict.
Future energy
Currently, there isn't enough energy being extracted from known sources
of fossil fuels to sustain 10 billion people. This means that humans will be
forced to turn to a new energy source before the end of the century. However,
it's a mystery what that new source will be.
"Energy is the basic resource which underlies every other,"
said Klaus Lackner, director of the Lenfest
Center for Sustainable
Energy. "And actually, technology is not quite ready to solve the [energy]
problem. We know there's plenty of energy in solar, in nuclear, in carbon
itself — in fossil
carbon — for probably 100 or 200 years (if we are willing to clean up
after ourselves and pay the extra to make that happen). But none of these
technologies are quite ready. Solar has its problems and is still too
expensive."
Carbon storage — a technology that prevents carbon dioxide and other
greenhouse gases from escaping into the atmosphere when fossil fuels are burned
— is still on the drawing board, though it looks possible, he added. "And
lastly, nuclear energy: if we were betting on that, we may have just lost that
one," Lackner said, referring to the nuclear disaster in Fukushima , Japan ,
earlier this year.
"Let me just give you a feeling how big today our energy
consumption is: In New Jersey ,
the energy consumption exceeds the photosynthetic productivity of the same area
if it were left pristine," Lackner said. "We have to have technology
help us out. I am optimistic … that the technologies can be developed to solve
these problems … but I am a pessimist because we lack the societal structures
which would enable us to employ these technologies, and we could very well fall
on our own faces."
In short, the future will match one of these two pictures: Either some
new, superior form of energy extraction (such as highly efficient solar panels)
will be widespread, or the technology, or its implementation, will fail, and
humanity will face a major energy crisis.
Mass extinctions
As humans spread, we leave scant room or resources for other species. "There
is good evidence that we are in the sixth massive species extinction of the
history of the planet, because of the incredible amount of primary production
that we take as a species to maintain 7 billion of us," Sachs said.
Aside from the lack of land and resources left for other species, we've
also caused rapid changes to the global climate, with which many of them cannot
cope. Some biologists believe that with the current rate of extinction, 75
percent of the planet's species will disappear within the next 300 to 2,000
years. These disappearances have already begun, and extinction events will
become more and more common over the course of the century. [10
Species Our Population Explosion Will Likely Kill Off]
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