I am a climate-change skeptic. Not about the science, which I think is pretty solid, but about our political will to prevent global warming from happening. CO2 levels have been rising since the Industrial Revolution. A corresponding temperature increase, though masked by large natural variations, is indicated by virtually all atmospheric models.
Will we slow our CO2 emissions? People in China, Brazil, India, and elsewhere want to live like Americans, with all the energy use that implies. Their governments are not about to put on the brakes. Nor, in our current political climate, do I see America taking the lead to reduce carbon emissions. Don’t get me wrong, I’m not knocking prosperity. Rich and happy beats poor and resentful any day. But, it comes with an environmental price.
The impact of a couple of billion more American lifestyles might be tempered and eventually offset by “green” technologies, but the numbers are overwhelming. The upward trend in CO2 seems all but certain to continue for some time. So, our climate is going to change, likely becoming hotter and more violent. What are we, as water professionals, to do?
The first step is to face up to the changes, to think differently about design standards, and move from optimization to robustness and loss reduction. When we realistically consider infrastructure having to last centuries, we must admit the recent past is a poor guide to the future climate and become more humble about our ability to forecast a “worst case” design standard.
Humble design works. Arguably the greatest engineer of the 19th century, John Roebling nevertheless appreciated the limits of his knowledge. He knew nothing about harmonic wind vibrations which would tear apart later bridges, or about today’s traffic loadings, and he would have been horrified at decades of deferred maintenance. He realized, though, his great bridge would be subject to a lot of forces he didn’t fully understand, so he massively overdesigned by today’s standards. I wonder what a modern “bean counter” would say to Mr. Roebling. (“Do you really need all that steel in the truss?” “Why four main cables?”) The Brooklyn Bridge stands proudly well into its second century because its designer was humble.
Enjoy our Featured Connection on Nonstationarity. And, engineers, be humble!