Fire-Prone Suburban Southwest Built At 'Catastrophic' Densities

"While this may all look like business as usual for legions of jaded, CNN-watching fire buffs, the enormity of this year's out-of-control blazes sets them apart.

So why on this scale?

Even by its own arid standards, the Golden State and much of the Southwest has just experienced an unprecedented summer heat wave, shrivelling crops and lawns and turning always-dry terrain into a blast furnace. Drought this year and last sucked the land dry. Rainfall across the region this past six months was just one-fifth of average levels.

Compounding the threat is the fact that despite soaring temperatures, Americans continue to head south and west.

Since 1990, an estimated eight million new homes have been built in the western U.S. states, chiefly in areas described as 'the urban-wild land interface,' code for uprooted city dwellers, many retired, who live in big houses or near pristine forests and deserts.

Those eight million buildings house at least 20 million new western residents.

And in Southern California, whose deserts are dotted with combustible scrub, brush and trees, that translates into ever-growing population density, meaning more houses, built ever-more closely together, and more people for the local fire department to protect.

That density can be catastrophic."