Gongol.com Archives: November 2021

Brian Gongol

November 17, 2021

Weather and Disasters Check the radar

If it is indeed true that a changing climate is likely to cause a greater frequency of extreme or severe weather events, then we ought not only to take steps to try to reduce the causes but also to mitigate the effects. (Besides, unless China's output of carbon dioxide is set to be radically curtailed, even if the United States achieves net-zero emissions, the situation will still get worse.) ■ One (relatively) small investment that could help is to increase the number of National Weather Service radar installations, particularly in the Midwest and in other locations prone to the most extreme events, like tornadoes. It's perhaps surprising but true that large portions of Tornado Alley (and adjacent regions) remain far outside the effective low-elevation reach of modern Doppler radar installations. ■ The problem isn't one that can be overcome with technology, because its cause is the curvature of the planet. Earth is round, which means that any straight line projected laterally from anywhere close to the surface in one location will ultimately end up elevated well above points far away. This is a particular problem when it comes to severe weather, because we care less about what's happening way up high than we care about what's happening close to the ground. ■ And while it's possible to infer some things about what's happening close to the ground from the signals bouncing back from high up in the clouds, it's better to get the data than to "read between the lines". There's good reason why some of the most sophisticated tornado researchers have portable radar units they can deploy right up close to the action. But while this research is fascinating and has great potential, it's not practical to hope that a portable Doppler will be in the right place at the right time to capture an emerging storm. They're tools for research, not for 24/7 surveillance. ■ Much is said about the consequences of climate change on communities that are, for one reason or another, regarded as disadvantaged. At present, your chances of having good coverage from a radar system are pretty good if you live in a big population center, and your chances of being left with lesser coverage tend to be stronger if you're in a more remote location. Improving the radar coverage for those outlying areas would be one way to offer a form of equity that may be growing in importance if we truly are on the verge of seeing a more extreme weather environment. ■ It wouldn't seem to cost all that much in the grand scheme of things -- certainly not against the backdrop of a trillion-dollar infrastructure plan. In Iowa, the gaps in near-surface radar coverage could probably be filled just by adding installations at Storm Lake, Mason City, and Vinton (midway between Cedar Rapids and Waterloo) -- places each about 100 miles away from the nearest installations, and located where they could serve populations suitably large to make the coverage helpful. Similar sites could be named for other states with high severe-weather potential. ■ Plenty of other technological advances are either here or on the way that will help to make forecasting and real-time weather surveillance better. But filling some of the gaps in our coverage -- and getting all of the most tornado-prone parts of the country covered down to the 3,000-foot elevation -- seems like the kind of investment to begin taking seriously now, before the worst of the long-range forecasts may come to bear.

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