Hypercanes

Hypercanes would have wind speeds of over 800 kilometres per hour (500 mph) and would also have a central pressure of less than 70 kilopascals (21 inHg), giving them an enormous lifespan. For comparison, the largest and most intense storm on record was 1979’s Typhoon Tip, with a wind speed of over 300 kilometres per hour (190 mph) and central pressure of 87 kilopascals (26 inHg).

The extreme conditions needed to create a hypercane could conceivably produce a system up to the size of North America (compare image of Typhoon Tip’s size at right), creating storm surges of 18 metres (59 ft) and an eye nearly 300 kilometres (190 mi) across. The waters could remain hot enough for weeks, allowing more hypercanes to be formed. A hypercane’s clouds would reach 30 kilometres (19 mi) into the stratosphere. Such an intense storm would also damage the earth’s ozone. Water molecules in the stratosphere would react with ozone to accelerate decay into O2 and reduce absorption of ultraviolet light.

Other scientists have theorized that the system, compared to a normal hurricane, would be considerably smaller,[citation needed] about 10 miles in diameter, making it more comparable to a tornado; however the largest tornado on record was estimated to be about 2.5 miles (4.0 km) wide.