Flood preparedness – climate change warning signs you should be heeding
By Jeremy Duensing
If we can learn anything from this past winter and spring, it’s that weather is becoming extremely volatile and more severe. Severe weather during summer months can pose a larger potential threat to the public as people are outdoors more so than any other season. The possibility of large populations being at or next to a body of water is also high, whether a river, ocean or lake.
The warm weather that comes with summer can dramatically affect regions across the country. Due to the increased moisture in the air, areas are more susceptible to heavy rains and severe storms that can impact a large area very quickly. This also increases the threat of localized flooding. It prompts two questions:
- When will severe storms affect your assets and infrastructure; and
- To what extent and severity?
Current technologies combine real-time data with accurate weather forecasting to give public safety officials an even more powerful tool for storm preparedness. Officials can use a real-time map of water levels and overlay an hourly weather forecast to achieve optimal awareness of when high water levels will coincide with high-impact weather. The most important parameters to watch in the event of a potential flood are something that should be known by every public safety official, emergency response manager and DOT director.
Especially helpful when severe weather such as hurricanes are expected, tide predictions can determine whether the impact from the combination of the tide and severe weather will be mild or detrimental. A storm that hits at high tide may require higher levels of preparation and resources than a storm that hits at low tide.
Measuring the level of a body of water is an extremely important measurement when determining if and when a flood can occur — yet immediate, accurate readings can be difficult to find. A public safety official can significantly increase awareness and determine potential flooding events with a real-time, geographic representation of high-impact ocean and river levels by plotting water level observations from thousands of ocean buoys and river gauges and analyzing them with other high-impact weather information, such as radar and local storm reports.
Knowing where and when the largest impact on the population will be due to high water levels can be highly effective in evacuations, so officials know what roads can stay open to the public and get them out of the danger zone as quickly as possible. This is crucial for DOT workers as well when stationed for response during a storm.
Hourly forecasts of ocean water levels can also be used to glean critical information about when ocean tide levels will be effected by forecast weather patterns. If the tide is expected to be higher than normal due to strong winds, this information can be very helpful to DOTs when determining whether to close certain roads or if wash-outs and shoulder floods are likely to occur.
To better predict how communities and infrastructure may be impacted, emergency response and public safety officials must have an understanding of wave conditions during a potential high tide. High waves can have an extremely larger impact during high tide and dictate the level of response needed if water levels get too high. Will the waves go over a city’s sea wall? This is vital information for the businesses and assets near the shore that officials must be aware of in case evacuation is needed.
Public safety officials can mobilize response teams faster and give regions advanced warning if they have a cohesive view of specialized weather forecasts and expected impacts, allowing them to better protect people and infrastructure while alleviating the potential for extreme danger.
With climate change, devastating storm surges could make landfall far more frequently – every three to 20 years. “500-year floods” are likely to occur once every 25 to 240 years. Needless to say, severe storms are here to stay and will become more frequent.
To prepare for storms, above all, being proactive is most important and much more effective than being reactive. An emergency response plan that includes all potential outcomes pertinent to a region or city is crucial. For example, a plan is needed when a river gauge may be over the tipping point or ocean level predictions are reaching dangerous levels. What are the immediate actions and what are the actions after it passes that point? Having an inclusive plan of all possible instances will only leave the region and its population in better hands when a storm hits.
A 2012 study in Nature Climate Change from Massachusetts Institute of Technology and Princeton found that what we previously considered a “storm of the century,” may actually be a “storm of the decade.” It’s important to remember that as our climate changes in how it affects severe weather, our perceptions and how to appropriately prepare for these storms should change as well.
Jeremy Duensing is the transportation product manager at Schneider Electric, based in Minneapolis, Minn. Jeremy joined Schneider Electric in September 1998 and has worked in the weather department since he graduated from the University of Nebraska in Lincoln with a Bachelor’s Degree in Meteorology.