With less than six weeks to go until the official start of the Atlantic hurricane season, forecasters will get an essential update just in time for the start of the season.
A new technology from the University of Wisconsin will help prepare more detailed forecasts and provide more reliable information to meteorologists and emergency planners, which should ultimately translate into better and safer outcomes for public safety.
The Advanced Dvorak Technique (ADT) is a satellite-based method for determining the intensity of tropical cyclones.
Planned enhancements include the use of full-resolution imagery from weather satellites, better identification of the location of the eye of each storm, and the ability to better analyze hurricanes that occur outside of tropical regions.
Developed by researchers at the University of Wisconsin’s Cooperative Institute for Meteorological Satellite Studies (CIMSS), the ADT provides an indication of how a storm might strengthen, especially as it approaches populated coastal areas.
Names of the hurricanes of the 2022 season in the Atlantic
Tropical storm and hurricane names are alphabetic and alternate between masculine and feminine. It is rare that the entire list is needed in one season.
Both 2020 and 2021 were very active Atlantic hurricane seasons, and if this year turns out to be like the previous two, updates will be welcome.
How will this new technology be used?
“For us, the goal is to provide a tool for forecasters to do their jobs better,” Tim Olander, CIMSS researcher at the University of Wisconsin, said in a news release.
The release also notes that since preparations for landfall and evacuations are costly and disruptive, “accurate forecasts with the help of ADT can have huge implications for emergency planners who must decide whether to issue an order and for residents who must follow it.
One of the ADT updates plans to tackle the problem head-on by providing better identification of the location of the center of circulation (often called the eye of the storm).
“Determining the center of circulation with the highest degree of accuracy is very important to the National Hurricane Center as it helps us start the forecasting process with the best initial conditions, which will likely make track forecasts more accurate,” said John Cangialosi, NHC’s senior hurricane specialist.
“Furthermore, the ADT itself performs better when the center position used in the technique is more precise, which in turn will provide better intensity estimates to the NHC.”
There are many different ways to obtain information for tropical forecasts. One of the most valuable is that of hurricane hunters, who fly planes directly into tropical systems to collect critical data used by NHC forecasters. The problem is that tropical systems are fluid and constantly changing, and hurricane hunters can’t fly 24 hours a day through each and every storm.
With more data, forecasters can reduce errors in the storm’s future track, called the forecast’s ‘cone of uncertainty’. Being able to reduce it, even a little bit, can help city planners, emergency managers and local residents know when to evacuate.
“When the NHC flies hurricane hunter planes into storms, they primarily rely on that ‘ground truth’ for current intensity estimation,” explained Phil Klotzbach, a research scientist at Colorado State University (CSU). its acronym in English).
“However, when there are no planes, NOAA relies on a variety of satellite estimation tools to assess the current intensity of a storm.”
One such tool includes subjectively analyzed Dvorak estimates from the Tropical Forecast and Analysis Branch as well as the Satellite Analysis Branch. The analysis of these tools and others is incorporated directly into the forecasts.
“In addition to these subjective analyses, the ADT also runs automatically every 30 minutes and provides estimates of storm intensity,” Klotzbach noted. “You can see how the NHC combines these tools in some of their forecast analysis of Hurricane Sam last year.”
The new software for improving ADT storm center positions is called Automated Rotational Center Hurricane Eye Retrieval (ARCHER).
Olander pointed out that previous versions of the ADT used infrared (IR) images, which, unlike visible images, are available at all times of the day. But the new version has additional images to help forecast.
“The technique uses multispectral satellite data to improve storm center determination compared to infrared imagery,” Olander said.
In addition to hurricanes in the Atlantic basin, the system works well for tropical storms in other oceans, where direct measurements may be more difficult to obtain.
“It is important to be able to estimate the intensity of a storm to help emergency planners prepare for any storm that may interact with coastal regions and population centers, as well as nautical interests such as shipping and the military,” Oliver added.
“Places like Canada, the UK and Europe are very interested in these types of storms and how they can affect them, as they can cause a lot of damage,” Olander said. “Extending the ADT to provide intensity estimates when the storm is in these regions can be a huge help to forecasters in those areas.”
Another busy season?
CSU is just one of more than a dozen academic institutions, government agencies and private forecasting companies that produce seasonal projections.
The CSU Tropical Meteorology Project team released its annual Atlantic Basin hurricane forecast earlier this month, announcing 19 named storms for this hurricane season, five more than normal. Of the 19 storms, nine are expected to become hurricanes and four are expected to become major hurricanes of Category 3 or higher.
Climatologically, about 30% of all Atlantic hurricanes make landfall in the United States. However, it is not necessary for all forecast storms to make landfall in the US for it to be considered a busy season.
“It’s important to understand that it doesn’t matter if there are 20 storms or one, if it hits you, it’s a busy season,” said Citizen Free Press meteorologist Haley Brink.
The chance of a major hurricane making landfall on the US coast is now 71%, well above the 52% average over the last century, according to the CSU report.
Statistics like these demonstrate why it’s important to start preparing now by reviewing your evacuation plans and making sure your evacuation kit is in order and up to date.