Ei välttämättä liity ilmastonmuutokseen, El Nino on muuttumassa La Nina ilmiöksi. La Ninan myötä Atlantin vedet viilenevät mutta samalla poistuu tuulien tekemä suoja USAn itärannikolta (wind shear, mikä onkaan oikea suomennos). Esim viime kesänä hurrikaanit kääntyivät pohjoiseen ennen mantereelle tuloa:
"La Niña may bring about a more severe hurricane season
One of the biggest consequences of a shift to La Niña is the higher likelihood of major hurricanes in the Atlantic Ocean. Hurricanes are built from several ingredients, but two parameters are especially important when it comes to ENSO: water temperature and air stability.
The ocean needs to be around
80 degrees Fahrenheit or hotter to form a hurricane, and the air above it needs to hold steady. El Niño years tend to heat up the Atlantic Ocean, but they also induce wind shear, where air rapidly changes speed and direction in the atmosphere, disrupting tropical storms before they can form. Still, the Atlantic was so abnormally hot last year that it fueled an
above-average hurricane season."
Climate change and the outgoing El Niño will likely ignite more weather extremes.
www.vox.com
Sitten tieteilijät pähkäilevät sitä että pitäisikö hurrikaanien voimakkuutta mittaavaa taulukkoa rukata eli lisätä 6. luokka:
"Category 5 storms used to be relatively rare. But climate change is making them
more common, research shows. And some recent Category 5 storms have had such high wind speeds that it would make more sense to assign them to a Category 6, if such a category existed, the authors argue.
The authors of the
new paper, James Kossin of the First Street Foundation and Michael Wehner of the Lawrence Berkeley National Laboratory, have been studying the effects of climate change on hurricanes for decades. They propose that Category 5 should include hurricanes with maximum sustained winds of 157 to 192 miles per hour, and that a new Category 6 should include any storm with wind speeds above 192 miles per hour."
Tähän mennessä (tai vuodesta 2013), 1 hurrikaani ja 4 taifuunia menisivät 6. luokkaan.
JOL
