Malthus on my mind

September 14, 2009

malthus normanborlaug

It just so happens that I have been reading Thomas Malthus’ Essay on the Principle of Population these days – another one of those famous books that I’d never gotten around to.  And it just so happens that Norman Borlaug died yesterday.  And it just so happens that T. R. Malthus keeps coming up in discussion about consumption, scarcity, the environment, global warming, etc.  Consider this riposte by Paul Krugman regarding feedback on earlier post of his.  It’s all related.

Some would say that Borlaug, the Nobel Prize winner, showed Malthus the door when he ushered in the Green Revolution.  (He rejected that term, though.)  Food supply didn’t have to inevitably fall behind the growth of population.  Except that Borlaug remained worried about population growth throughout his life and feared that if the rate of increase wasn’t checked, his work would have done no more than bought a temporary reprieve from famine to the world.  Borlaug, who seems to have been a deeply compassionate and extremely sensible man (see this address) was also criticized by many for a narrow technocratic approach to the problem of feeding the world – Simple, we’ll breed more productive wheat! – understood the wider context within which agriculture sits.  He wasn’t trying to get the developing world hooked on Western fertilizer and seed products – he was trying to feed the world.  He regarded such critics as elitists who didn’t worry about where their next meal, or their family’s meal, was coming from.

Oh dear, so much comes together here, not the least of which is just how great those 18th century thinkers were.  Did Malthus forsee it all?  Now we associate him with Carlyle’s remark about economics being the dismal science:  nothing but famine, war and pestilence bring production and consumption into balance, that’s the future.  Dismal, yes, but that’s not what Carlyle was talking about anyway. And Malthus was just trying to introduce some hard nosed good sense into a discussion too much dominated by optimistic good feeling of people like Condorcet.  In situating ourselves within Nature, the universe, we have not advanced much beyond Rousseau and Voltaire’s argument of more than 200 years ago.

Krugman’s gripe was with people calling him a (neo) Malthusian when he rantedabout congressmen being treasonous to the planet and the sky falling and all that climate change stuff.  But he was way off base, as this commenter pointed out:

“[Krugman wrote] We only think Malthus got it wrong because the two centuries he was wrong about were the two centuries that followed the publication of his work.”

Only an economist could say that with a straight face.

Shorter version: “Malthus was wrong because his theory had zero predictive ability”.

Yes, I thought of that too.  If only Malthus had published his work in 1598, he would be looked upon as an undisputed master of analysis and prediction!   On the other hand, just this evening, here at a conference on water resources and climate change, a speaker remarked that maybe bringing the Green Revolution to India wasn’t such a “wise idea” because a significant consequence has been unregulated and unrestricted pumping of groundwater for irrigation, which is bringing the nation to the point of  massive water shortages.  Maybe Malthus should have written about water supply instead of grain supply, although it comes to the same thing in the end.

Or does it?  The same speaker said we should never underestimate our ability to adapt, an intellectual mistake that neo-Malthusians make a lot.

Advertisements

USA by the numbers

September 12, 2008

Where is everyone?  Crowded on your doorstep if you believe the group NumbersUSA, a group dedicated to reducing all immigration, even legal immigration.  (I heard about them from this NPR story.)  Whatever their real reasons for opposing immigration may be – misanthropy, nostalgia, bigotry, fear of change – their argument about environmental degradation in the USA is a lot of hooey.  The biggest problem with our treatment of the natural world here in the US of A is our history of gobbling up space as if there’s no tomorrow!  Consider these maps:

This is a map of the population density (people per square mile) in the lower 48 with 2004 Census data.  Note that nearly all of the land is settled at the lowest density on the map, less than 250 people per square mile.  (Much of it is at much less than that!)  The high concentrations are where the cities are.  If we weren’t so violently opposed to city life…

“I view great cities as pestilential to the morals, the health and the liberties of man. True, they nourish some of the elegant arts; but the useful ones can thrive elsewhere; and less perfection in the others, with more health, virtue and freedom, would be my choice.”

–Thank you, Thomas Jefferson!

…perhaps we would concentrate our citizens there and leave the rest of the continent as a garden.  Even in those diseased parts of the nation that are highly urban, the density is not nearly so great as what is common in the rest of the world.  Consider this next map of the metro area around New York City.

Note how the higher density areas are relatively small, and are almost all within the five boroughs of NYC.  The area to the northeast of Manhattan, Bergen County, NJ, is one of the most densely populated regions of the country, but it is settled at about 2500 per square mile.  As I like to say, the USA is mostly unpopulated empty space.  To put these figures in world perspective, consider this chart:

 This graph shows many data items and has two axes.  The black curve on the top (refer to left axis) shows that about 97% of the USA population lives on only 50% of its land.  80% of the population lives on about 7% of the land.  (15% of the population lives within 50 miles of I-95 between Boston and Washington, DC.) 

The blue curve refers to the right axis, and shows that 90% of the land is settled at densities so low that they barely register on the axis. 

Manhattan, our most densely populated place, is only twice as dense as ALL of Bangladesh.  If you factor in Brooklyn, Queens, Bronx, and Staten Island, NY City is about as dense as ALL of Japan.  Many world cities are much denser than American ones as few cities in the USA even approach the density of NYC, let alone Manhattan! 

The horizontal dashed lines show the densities of some modernized countries – clearly people are crammed in – comfortably from what I’ve seen and heard – at rates that far exceed what we have here in the USA.

So, if we want to pave over the USA and have everyone live in a McMansion, then maybe we should cut back on our immigration and population growth.  If we want to use resources wisely, I don’t see anything to worry about.