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The biggest storms and how they’re getting bigger

A tale of storms and how the best part isn’t here yet

If 2017 seemed like the year of storms to you, then you’re not mistaken – the year, in particular, saw quite a few high-intensity storm events from around the world. Now, when it comes to storms and storm seasons in the different oceans of the world, there are quite a few parameters to measure and quantify them – ranging from peak wind speed to the number of storms in a season to pressure at the eye of the storm and more. But, overall, these factors combine to make storms what they are today – deadly, frequent and somewhat unexpected. If you delve into the past of storm seasons around the world, the story isn’t much different.

Storm stats – what do they mean
Tropical storms are usually measured in a number of ways, but a couple of readings that you will mostly see are peak wind speeds and lowest central pressure. The first is measured at 10m above the earth’s surface as an average of sustained wind speed over time (1min in US and 10min elsewhere) by satellite readings. Central pressure is measured by reconnaissance planes doing flybys over the storm and is also an indicator of whether the storm is growing or dying out.

Typhoon Tip (1979)

When it comes to size and speed, Typhoon Tip ranks right up there on the top with some of the strongest storms ever. At its peak, its central pressure dropped to 870 mbar, which is the lowest ever observed on Earth. This translated to wind gusts over 300kmph. And that’s not even the most overwhelming fact about Tip – at its peak, it was 2,220km wide. To put some perspective on that – if it were to happen over India today, it would stretch from Delhi to Chennai and pretty much destroy everything in its path.

Cheat box
Just in case you’re also confused about what’s the difference between hurricanes, typhoons and cyclones, here’s the thing – there’s none. It’s just about where they’ve originated:

  • Hurricane: Atlantic and Northeast Pacific
  • Typhoon: Northwest Pacific
  • South Pacific and the Indian Ocean: Cyclones

Fortunately for us mortals, the storm weakened before making landfall in Japan on Oct.19, 1979 – but it still was the most intense storm to hit the island of Honshu in almost a decade, killing more than 86 people and injuring hundreds. Even the city of Tokyo saw buildings swaying with the force of high-speed gusts.

Typhoon Nancy (1961)

Nancy’s rank among the top storms in the world isn’t without controversy. Back in 1961, wind readings were most likely overestimated due to deficient technology and an inferior understanding of how typhoons work. But assuming that the readings were accurate, the numbers throw it right to the top with a peak wind-speed of 345kmph! It also qualifies for the record of the longest Category-5 storm in the Northern hemisphere yet – it lasted in category 5 for five and a half days before making landfall.
When it made landfall in Japan, as a category 2, it caused more than $500 million in damage and 200 deaths.

Hurricane seasons around the world
Season Name Starts Ends
Atlantic Hurricane Season June 1 November 30
Eastern Pacific Hurricane Season May 15 November 30
Northwest Pacific Typhoon Season all year all year
North Indian Cyclone Season April 1 December 31
Southwest Indian Cyclone Season October 15 May 31
Australian/Southeast Indian Cyclone Season October 15 May 31
Australian/Southwest Pacific Cyclone Season November 1 April 30

Hurricane Harvey (2017)

We’ve all heard of Hurricane Harvey this year. Part of the extremely active 2017 Atlantic Hurricane season, if Harvey’s peak wind-speed of 215kmph and lowest pressure of 938 mbar don’t impress you, look again. Hurricane Harvey is the costliest tropical storm on record, causing more than $200billion in damages. It also broke a 12-year streak of no major hurricanes making landfall in the United States. That’s not all – with peak rainfall measurements of 1,539mm Harvey was also the wettest tropical cyclone on record in the US.

As expected Harvey had intensified into a hurricane

Hurricane Ophelia (2017)

Just like Harvey, if you’re looking for higher wind speeds and lower pressures on Ophelia, you’d be disappointed. The significance of Ophelia lies elsewhere. Tropical storms usually form on warm waters – which is conducive to create the conditions required (temperature difference, pressure drop) for wind speed to increase. That is why it came as a surprise to meteorologists and ordinary people alike that Hurricane Ophelia affected Ireland, the UK and parts of Europe. It was the easternmost Atlantic major hurricane on record.

If you want to grasp just how unexpected the storm was, take a look at the image that the US National Hurricane Centre tweeted.

The NHC chart that shows the incomplete prediction

It didn’t account for storms going north of 60 degrees North latitude or eastward than 0 degrees longitude – ending up with a jarringly incomplete storm prediction graph. Ophelia wasn’t just a surprise this year – it was the strongest storm to hit Ireland since the 1960s.

All of these big and unique storms bring us to one question – why are storms defying reason and where are they headed?

Climate change?

While there has been much debate about whether climate change is real or not, there is one undeniable fact about the issue that we can confidently share with you – IT IS REAL! Now with that taken care of, it isn’t really straightforward to blame climate change for the increasing frequency, range and strength of storms. And no, as stated earlier, we’re not being climate change naysayers here.

The typical structure of a tropical cyclone in the Northern Hemisphere

When it comes to a storm formation, there is a wide array of factors responsible – some might say too wide. But some of these factors do point at bigger storms. For instance, warmer ocean waters and higher sea levels are both favourable to increasing the intensity of storms – and both are directly affected by climate change. While warmer seas directly affect wind speed, both the factors contribute to increased flooding – warm waters causing increased precipitation and higher sea level causing more coastal flooding.

Even though it might appear that storms are increasing in frequency, that is not entirely true especially if you look at historic storm season data. Some models even project a decrease in frequency. What is happening, though, is that whatever storms do occur now, have higher intensities. And if climate change keeps heading in the direction it is right now, there’s no sign of Earth’s stormy days and nights being over anytime soon.

Arnab Mukherjee

Arnab Mukherjee

A former tech-support desk jockey, you can find this individual delving deep into all things tech, fiction and food. Calling his sense of humour merely terrible would be a much better joke than what he usually makes.