Weather experts are calling for  new, stronger category for hurricanes. They say this is because climate change is causing more powerful storms. Scientists in  USA want to extend  current scale used to measure hurricanes. This scale ranks storms from 1 to 5. A category five is currently  strongest. This is when winds reach 252 kph. The meteorologists say  new category of 6 is needed for winds of over 309 kph. Their studies show that in  past decade, there have been five hurricanes and typhoons that would have been  category 6. Hurricanes and typhoons are the same weather phenomenon.  former start in  Atlantic Ocean, while  latter occur in the north-western Pacific Ocean.
Meteorologist Dr James Kossin said it would take  long time for  new category 6 to be accepted. It would need the USA's National Hurricane Center to start researching more intense storms. Dr Kossin hopes to, "inform broader discussions about how to better communicate risk in  warming world". He said "significantly increasing" temperatures are caused by greenhouse gas emissions. This increase in emissions is heating oceans, which gives  water extra energy. This makes hurricanes more powerful, with much higher wind speeds. He believes there will be  greater number of "super-storms" in  future. He said: "These storms keep getting stronger as  climate changes."