Climate change and population

Demographers predict that Earth's human population will reach 7 billion by Halloween of 2011. Global development seeks to to increase the affluence and health of the world's underdeveloped populations. With increased affluence comes more purchasing power to consume anything from toys to bottled water to cell phones to cars to pets.

In their book, Healing the Planet, Paul and Anne Ehrlich proposed an equation I=PAT. It's a heuristic, or cognitive short cut, to represent environmental impact.

Impact = Population x Affluence x Technology

Like any heuristic, it has some shortcomings, but it's useful because it gets us to glimpse the unseen. Impact can be expected to increase if there is a net increase of P, A, and T. If affluence and technology remained steady but more people use them, impacts increase. If the population and technology remained steady but affluence increased, then more purchased stuff by the population increases impact. If population and affluence remained steady but technological impacts went up because of proliferation or size, then impact increases.

Today, we have all three. There are more people with more purchasing power buying more pieces of technology that net more material and energy use than ever before. Today's I=PAT is much larger than 1950's I=PAT even though we have had so much progress in that time.

So when we get to an issue like climate change, it's been easy to talk about energy efficiency or renewable energy. Environmentalists in the United States generally laud wind power and eschew coal. In a world with lots of poor people it's been important to laud global development efforts that afford people the ability to meet their daily necessities of food, water, shelter, community, and healthy environments. Beyond that, most people hope that people can meet more than the necessities but be comfortable and happy. There's the rub.

What's a necessity, or as the Brundtland Commission called it in their report Our Common Future, a "need"? If we all "need" to have heated or cooled housing, cars, and electronic gadgets, how can we expect to stop a problem like climate change if development mandates increased affluence and technological dispersion for 7 billion people later this year and 9 billion by 2044? With no appreciable reduction in fossil fuel demand by efficiency, are we on a collision course with the climate?

Get some insights on it from Lester Brown and Robert Engelman on Hard Ball. This is a hard nut to crack and it's impressive that MSNBC took it on at all.

Visit msnbc.com for breaking news, world news, and news about the economy

Sustaining what? For whom? For how many? Andrew Revkin from Dot Earth

Demographers estimate that by 2050 the Earth will house 9 billion people. As of now, humans only have one planet that we can live on. This is a bit of a conundrum.

That is the primary conundrum that Andrew Revkin explores on his blog, Dot Earth hosted by The New York Times. Revkin has covered human-environmental issues as a journalist for 30 years for a number of media and is the author of three books. Today, he came to Penn State and gave a presentation on this complex but inescapable issue.

First, human population is growing. Today, there are ~6.8 billion people and many more to come. Second, global development institutions and initiatives, expanding markets, technological innovation, and political, cultural, and climatic changes will change how those people live. To support that development will require a lot of thought and effort on how to supply the developing world with energy, and currently the industrial economies rely overwhelmingly on fossil fuels. Third, the human and ecological impacts of all of this development are large and many are damaging. They include climate change, large scale visible pollution, and massive species loss.

Revkin explains industrial human activities today with this metaphor: Imagine that you wake up in a car and you are in the driver's seat. You have never driven before and have not taken driver's ed. There is no manual for how to drive the car and well, the car is going about 50 mph and accelerating into a foggy night. If there is a curve ahead, will you know what to do?

He said, "I think it's still kind of even odds that we'll hit the guard rail or that we'll fly off or that some large part of us doesn't make it around that curve."

It is with a combination of skepticism and hope that Revkin invites readers into a more fruitful conversation. "We are a young species," he says. He doesn't blame us for what has happened. In a sense, it's as if we are just waking up to the ramifications of our intelligence. If we are seeing things differently, then we have a chance to do things differently by listening to scientists who have told us, repeatedly, that we live on a finite planet with finite resources. If we smartly design our artificial world from cities to economic instruments, perhaps we won't reach peak everything against peak us. Maybe there is some more optimal way to be without a global catastrophe. Maybe.

What is sustainability in such a world? Or as Revkin says, "Well sustain what?" Watch his short answer to Sustainability Now:

To have a sustained relationship with the planet around us requires a lot of innovation, a sense of resilience, and a sense of engagement that the human-planet relationship need not be the way that it's been...Take energy. What I say is energy for the long haul. What is an energy policy that works for the long haul? And that means having a durable sense of responsibility that it's not just about the now but about how you utilize resources that makes sure that people who come after you have some options as well and that nature has some space as well.

What is that responsible energy policy? Where do we put our efforts in this hot and crowding world? Over the past year we've talked about smart grids, about home and business software to help reduce consumption, about energy deregulation, the intransigence and polarization of our policy makers on climate and environment issues, and of course on Marcellus Shale gas development in Pennsylvania (Revkin posted about shale gas rhetoric and distortions today). Energy comes up again and again.

What would you ask Andrew Revkin as a follow-up to his response? Perhaps we can send them to him.