Experts suggest introducing new category for intense storms

The frequency with which extremely powerful tropical storms have been seen in the last decade has prompted some experts in the field to suggest that a new category should be added to the existing nomenclature of intense storms. To this end, the introduction of Category-6 is being discussed, which will be used to categorize storms with wind speeds of 192 miles per hour or more.

This suggestion has been made following a study that states that the strongest tropical storms each season are getting progressively more intense, which has been attributed to climate change.

The current system follows the traditional five categories, which are given within the Saffir-Simpson scale. This scale has been in use for the last 50 years and it has been suggested that it no longer adequately categorizes the strongest storms which present with the most amount of destructive ability.

Due to this, two scientists voiced their concerns and suggested the introduction of Category-6 during the proceedings of the National Academy of Sciences on Monday.

According to the current classification, Category-5 applies to any storms with wind speeds of 157 miles or more. Experts believe that this does not accurately describe the intensity and the subsequent hazards of storms which are closer to the 200 miles per hour mark.

There are also instances when that limit has been exceeded, which further complicates matters.

In such situations, it is necessary to ensure that the public understands the severity of a weather system, which can only be achieved with a more comprehensive system of categorization.

While that is the perspective of one set of experts, others believe that the introduction of a new category is not necessary as the change would be based on wind speed, which does not take into account the effect that the water involved has on a weather system, which is a far more deadly proposition.

The Pacific has seen five storms that have exceeded wind speeds of 190 miles per hour, since 2013, out of which two hit the Philippines. All five of these storms would have made the cut for the new category, which has become a stark reality of the weather conditions in today’s world.

It is also important to note that warming global conditions have made such strong storms even more common, especially in regions such as the Gulf of Mexico, where many of the storms that end up hitting the United States gain a significant amount of momentum, becoming even stronger in the process.

Michael Wehner, a climate scientist at the Lawrence Berkley National Lab, who also happens to be the lead author of this study, stated the following, “Climate change is making the worst storms worse.”

To clarify, the study does not suggest that climate change has made storms more frequent but that climate change has made the most intense seasonal storms even stronger with each progressing year.

Brian McNoldy, who is a hurricane researcher at the University of Miami, explained that out of the total number of storms experienced each year, the proportion of major hurricanes is increasing. It is important to note that Brian McNoldy said so as an independent entity and was not a part of the aforementioned research project.

The study has reinforced the idea of introducing Category-6, which was a suggestion that was initially made after Typhoon Haiyan reached 195 mph wind speeds, while passing over the open sections of the Pacific. The study has also stated that Typhoon Haiyan is no longer considered an isolated incident.

It is important to note that storms which cross a basic threshold for wind speed are categorized as hurricanes if they form to the east of the international date line and typhoons if they form to the west of the international date line.

Similarly, in the Indian Ocean and Australia, they a categorized as cyclones. With that in mind, the five storms which exceeded the 192 miles per hour mark are:

• Haiyan (2013)- Killed more than 6,300 people in the Philippines.
• Hurricane Patricia (2015)- Reached wind speeds of 215 miles per hour before losing intensity slightly and hitting Jalisco in Mexico.
• Typhoon Meranti (2016)- Reached 195 miles per hour before sliding by the Philippines and Taiwan to it China.
• Typhoon Goni (2020)- Reached 195 miles per hour before losing intensity, yet killed dozens in the Philippines.
• Typhoon Surigae (2021)- Reached 195 mile per hour before sliding by various parts of Asia and Russia.

Jim Kossin, a former NOAA climate and hurricane researcher, who has co-authored the study and now works with the First Street Foundation stated the following, “If the world sticks with just five storm categories as these storms get stronger and stronger it will more and more underestimate the potential risk.”

Kossin explained that Pacific storms are more intense because there is less land to hamper their progression, unlike in the case of the Gulf of Mexico and the Caribbean region. While no Atlantic storms have reached or crossed the 192 miles per hour mark yet, Kossin and Wehner stated that warming conditions could make that possibility far more likely in the near future.

This is because as temperatures rise, the number of days which are conducive to the making storms more intense in the Gulf of Mexico will also increase. In the current scenario, that would be a period of 10 days every year, during which conditions are ripe for a Category-6 system to develop.

Considering the rate at which temperatures continue to rise, that period could soon become a month long as the world heats up over 3 degrees Celsius above pre-industrial levels. In that case, it would be even more likely that a Category-6 system could develop in the Atlantic as well.

According to Kerry Emanuel, a hurricane expert at MIT, “Wehner and Kossin make a strong case for changing the scale.”

Yet, he believes that the introduction of this change is unlikely as authorities are aware of the fact that most of the damage caused by hurricanes comes from flooding and storm surges.

According to Jamie Rhome, who is the Deputy Director of the National Hurricane Center, “When warning people about storms, we try to steer the focus toward the individual hazards, which include storm surge, wind, rainfall, tornadoes and rip currents, instead of the particular category of the storm, which only provides information about the hazard from wind. Category 5 on the Saffir-Simpson scale already captures ‘catastrophic damage’ from wind so it’s not clear there would be a need for another category even if the storms were to get stronger.”

University of Albany’s Professor for Atmospheric Sciences, Kristen Corbosiero and former Federal Emergency Management Agency Director Craig Fugate, have concurred with McNoldy assessment, stating that there is no need for the introduction of Category-6.