The researchers found that the probability of storms reaching hurricane status (category 3 or higher on the Saffir-Simpson scale with winds above 110 mph or more) has increased decade after decade.
The new research builds on previous studies that had shown a probable increase in the strongest storms with global warming global oceans, but the data did not rise far enough to confidently estimate that the increase was due to human-caused global warming. and not to natural cycles that can span decades. The latest results add another 11 years to the dataset, which helps clear up statistically significant trends.
“Signals really begin to emerge beyond the noise of indoor climate variability when looking at (about) 40 years of data compared to their previous study that looked at (about) 25 years of data,” Colorado State University hurricane researcher Phil Klotzbach, who was not involved in this study, told CNN in an email interview.
Research by Kossin and his team has crossed the globe, showing that storms around the world are becoming stronger and therefore more destructive, as the upper end of storms on a scale produces a disproportionate amount of damage and death.
“Almost all the damage and mortality caused by hurricanes is caused by major hurricanes (categories 3 to 5),” said Kossin. “Increasing the likelihood of having a major hurricane will certainly increase this risk.”
The study reveals that global warming has increased the temperature of the sea surface in regions where tropical cyclones are formed. The combination of these hot temperatures and changes in weather conditions have allowed storms to reach higher intensities more easily.
Super Cyclone Amphan strengthens to new record
A current example of what the study says is happening most frequently can be found in Bengal Bay, where Super Cyclone Amphan reached the top of the ladder with winds equivalent to a category 5 hurricane on the Saffir-Simpson Ladder.
On Monday, the storm hit sustained winds of 270 km / h (165 mph), making it the strongest storm ever recorded in the Gulf of Bengal, according to data from the United States Joint Typhoon Warning Center.
“Sea surface temperatures are much warmer than normal in the Gulf of Bengal at the moment,” said Klotzbach. Warmer ocean temperatures are one of the main ingredients the new study has shown in explaining the observed increase in the force of the storm.
Interestingly, this was one of the few locations on Earth where the authors didn’t see the intensity of the storm increase.
“The trend we have found is not very evident in the Northern Indian Ocean, but this is mainly due to the fact that the data is so scarce and it is difficult to identify trends especially noise,” said Kossin.
“I suspect that if they extended the study to 2018 and 2019, it would become significant,” said Klotzbach. “Last year he was absolutely mad in the Northern Indian Ocean, particularly in the Arabian Sea.”
Evidence shows that global warming is strengthening tropical cyclones
Finding trends in global tropical cyclones has traditionally suffered from inconsistent data records dating back several decades, said Ryan Maue, a private sector meteorologist not involved in recent research.
Scientists have long theorized that the warmer oceans of human warming of the climate would likely have resulted in stronger hurricanes and typhoons and climate patterns also show an increase in the future, but observations have not conclusively shown the increase so far, mainly at due to inconsistent and short data sets.
“Here, the authors apply an objective technique over four decades of satellite data to create a consistent record of the global intensity of tropical cyclones,” said Maue.
“Their results are consistent with the theory that rising sea surface temperatures are actually increasing the intensity (but not the frequency) of storms that are stronger than at least the hurricane’s greatest force.”
“Like all aspects of the climate, there is an element of natural variability at stake,” said Kossin. “Our study does not formally distinguish natural causes from causes of human activity and the trends we have encountered are most likely due to a combination of both,”
While the exact causes are complicated, Maue said, this research increases confidence in climate models that show that global warming is and will continue to increase the intensity of the tropical cyclone in the future.
Coffee enthusiast. Travel scholar. Infuriatingly humble zombie fanatic. Thinker. Professional twitter evangelist.