A key challenge for planning and design professionals is figuring out how to incorporate the uncertain impacts of climate change in their plans.
We try to avoid building in flood-prone areas, but we haven’t forecast how climate change will alter flood zones. And what about sea level rise? If you buy a property that's less than 2m above sea level, it could be like a 99-year lease: at the end of it, you walk away with nothing.
There are lots of other areas where change matters. Hotter weather means we need to work harder to keep buildings cool without using more energy for air conditioning. Heavier rainfalls mean we need to design stormwater systems to carry the load (or hold back the peak flow longer). Less rain in growing seasons means we need more efficient irrigation systems, or different crops. Stronger winds mean buildings and other structures need to withstand the extra pressure.
But we don’t know how severe these changes will be, so it’s hard to set standards to guide engineers, architects and other designers. And we depend on these standards for responsible management of design risks.
And that’s just for adapting to change.
We also need to understand how to mitigate climate change through reduced carbon emissions. If a country like South Africa is going to achieve targets, we’ll need to change the way we plan projects and evaluate designs.
It’s all very well saying more people need to use public transport, for example, but how should transport planners look at the way they identify infrastructure needs? We routinely perform analyses that see how congested the roads are, and recommend improvements to reduce traffic delays during the peak periods. If we keep doing that, we’ll encourage more and more car travel, until eventually we run out of space to widen roads, and we’ll have a system that doesn’t work for cars or buses or even the pedestrians and cyclists who might dare to navigate this heavy traffic.
We should see it as unethical for professionals in the built environment to continue with business as usual. Some change is inevitable, and we need to do what we can to allow cities to adapt, and prevent avoidable change. If we don’t, it won’t just be the next generation asking, “what were you thinking?” but also the litigation lawyers rubbing their hands in glee at the tsunami of cases brought for design failures.
Engineering standards change as new materials are used in construction, and new building methods are adopted. These things change the science on which design is based. If they were not updated, we would be negligent. Climate change presents us with the same need to update our methods of analysis. The best science available says that change is coming, and it’s time to do something about it.
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If you are interested in the debate about sea level rise, have a look at Skeptical Science, where you'll find some healthy discussion between people who believe it's happening, and those who don't. The discussion covers topics like expansion of water as it heats up, how silt does (or doesn't) raise sea levels, the influence of building dams on sea level, the absorption of carbon dioxide by the seas, the role of melting glaciers, and so on. You could view original article in the link as just an intro - there are pages and pages of comments that are very informative.