Saving lives: The accurate forecast
Wednesday, October 16, 2013, 2:12 -
Reaching the equivalent strength of a Category 5 hurricane just a day before landfall, Cyclone Phailin made worldwide headlines and will go down as one of the strongest cyclones to ever form in the Indian Ocea. Dozens were killed in East India, but many believe that early warnings and mass evacuation efforts spared the region from higher loss of life.
THE EVER-IMPROVING WEATHER FORECAST
Before a warning can be issued, forecasts must be made. The accuracy of these predictions is vital to issuing detailed warnings and triggering evacuations.
Predicting hurricanes, typhoons and tropical cyclones is no easy job. Some of the most advanced weather researchers in the world have focused on forecasting hurricane tracks, and with much success. Since the turn of the 21st century, Atlantic hurricane forecasts – issued by the U.S. National Hurricane Center – have improved by up to 50%. When forecasting a hurricane’s location three days ahead of time, a typical forecast is now typically only 160 kilometres (100 miles) off.
These more accurate forecasts have led to earlier warnings, and it allows for more confident messaging within them. But it’s not just getting the forecast right that counts. It’s how you say it, too.
WHAT’S THE MESSAGE?
The issuing of weather warnings is as much a sociological challenge as it is a meteorological one.
There are many examples of this sociological spin within weather warnings. For example, the Saffir-Simpson wind scale creates simple categories, from 1 to 5, that describe the possible wind damage associated with different hurricane strengths. Inspired by the Richter scale for earthquakes, it is now a widely understood rating scale, and the benchmark for communicating the severity of a hurricane.
Another example is the U.S. Storm Prediction Center’s usage of the wording “tornado emergency” under rare and particularly dangerous situations, when a tornado warning in itself may not elicit the response required for immediate public safety.
Two recent examples of this were in May 2013, during the Moore tornado and El Reno tornado, in Oklahoma. It’s one thing to issue a warning, and another to have it understood and generate action. In many cases, the wording of a warning is just as important as the existence of the warning itself.
According to Nigel Snoad of Google Crisis Response, the key to good warning text is a combination of good content and actionable information. Instead of just giving details of the weather conditions expected, it is equally important to compliment that information with actionable information.
A good warning must answer the question “what do I do?”
When it comes to hurricanes, the most important “actionable information” is usually the message to evacuate. Large-scale evacuations have become more common in recent years in the United States.
When faced with an imminent landfall of a strong hurricane, evacuations are seen as the most effective way of putting millions of people out of harm’s way. Over 800,000 people were evacuated in the days before Cyclone Phailin made landfall in East India. This undoubtedly saved many lives. But what convinced the Indian government of seeking such a large-scale evacuation operation? Was it the reliability of the forecast?
Or was it the specific wording used in the weather warnings?
When it comes to Phailin, one key factor should also be considered: a devastating cyclone still in the memories of many East Indians.
WILL HISTORY REPEAT ITSELF?
Perhaps the most important consideration in Phailin’s relatively low death toll was a powerful storm that occurred just 14 years prior. The 1999 Odisha cyclone was a much more destructive storm than Phailin. The Odisha cyclone made landfall with stronger winds, struck a more populated area, and stalled over the region for a prolonged period of time.
The resulting floods were overwhelming, and were considered one of India’s worst floods in the past 100 years. Most importantly, the 1999 storm made landfall just a couple hundred kilometres east of where Phailin eventually came onshore.
The memories of that super cyclonic storm are likely what saved many lives this time around. The fear of a repeat ensured that Phailin’s warnings would be heard, loud and clear.
NOT ONE FOR THE RECORD BOOKS
In the end, all of these factors discussed are key pieces to the extreme weather puzzle. Improvements in weather forecasts, warnings and mitigation tactics will continue to save lives. It is the job of meteorologists around the world to help inform the public, and improve the way society responds when faced with a threatening storm. But nothing compares to the fear of history repeating itself.
The memory of the 1999 Odisha cyclone played a substantial role in East India, setting the precedent for what might happen if evacuation orders were ignored. Decades from now, Cyclone Phailin likely won’t have a prominent spot in the record books. And that’s a very good thing.