Difference between hurricane and typhoon

Typhoon, hurricane, cyclone: ​​what's the difference?

Typhoon Usagi - named after the Japanese word for "hare" - is the third and strongest Pacific typhoon to have formed this year. It was called a severe typhoon or "super typhoon" after meteorologists measured gusts of wind at up to 260 kilometers per hour.

If you've never lived in Asia, you might be wondering what a typhoon feels like. But anyone who has ever experienced a hurricane or cyclone knows the answer for a long time.

Because the terms “hurricane”, “cyclone” and “typhoon” all describe the same weather phenomenon. The name scientists give these storms depends on the region in which they occur.

In the Atlantic and North Pacific, the storms are called "hurricanes", after the Caribbean god of evil.

In the Northwest Pacific, the same mighty storms are called "typhoons". In the southwest Indian Ocean and southwest Pacific, they are known as "heavy tropical cyclones".

In the northern Indian Ocean they are called "severe cyclones". In the south-western Indian Ocean one speaks simply of “tropical cyclones”.

To be classified as a hurricane, typhoon, or cyclone, a storm must reach wind speeds of at least 119 kilometers per hour.

When the winds of a hurricane reach speeds of 179 kilometers per hour, one speaks of a "strong hurricane".

If a typhoon reaches 150 miles per hour - like Usagi - it is called a “super typhoon”.

DIFFERENT SEASONS

While the Atlantic hurricane season runs from June 1st to November 30th, the typhoon and cyclone seasons follow slightly different patterns.

In the northeastern Pacific, the official season runs from May 15th to November 30th. Typhoons are most common in the Northwest Pacific from late June to December. Cyclones form over the northern Indian Ocean from April to December.

Whatever they are called, these monster storms are powerful natural phenomena that can develop tremendous destructive power.

According to the US National Ocean and Atmospheric Administration (NOAA) National Hurricane Center, a hurricane eye - the quiet center where pressure is lowest and air temperature is highest - has an average diameter of 30 miles. However, individual eyes can also reach a diameter of up to 200 kilometers.

The strongest storms, which correspond to category 5 on the Saffir-Simpson scale, have caused winds of over 250 kilometers per hour.

With the help of satellites and good models, such storms can be predicted several days in advance and can be followed relatively well. But as Hurricane Sandy recently showed, predicting the exact path a hurricane or typhoon or cyclone will take after it has formed remains difficult.

CONSEQUENCES OF GLOBAL WARMING?

In recent years, scientists have debated whether human-made global warming is making hurricanes stronger or more frequent.

In theory, higher temperatures in the atmosphere should lead to higher temperatures on the ocean surface, which in turn should lead to stronger hurricanes.

The number of Category 4 and 5 hurricanes nearly doubled worldwide from the early 1970s to the early 2000s. In addition, both the duration of tropical cyclones and their highest wind speeds have increased by around 50 percent over the past 50 years.

So far, however, scientists have not agreed on whether there is a connection between climate change and hurricanes.

"The mean maximum wind speeds of tropical cyclones are likely to increase, but possibly not in all ocean basins," said the 2012 report by the Intergovernmental Panel on Climate Change.

"It is likely that the global frequency of tropical cyclones will either decrease or remain essentially the same."

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Article published in English on September 25, 2013