The obvious thing that Pinaki Chakraborty has forgotten to factor into his study – in which he finds that hurricanes now take 33 rather than 17 hours to weaken when they make landfall – is that 50 years ago there wasn’t technology such as doppler weather radar and sophisticated satellite measuring wind speeds around, and drawing a linear trend through a bunch of values on a scatter graph doesn’t prove that climate change and warmer sea temperatures are the cause of that slowing down of that decay.
This is just another study in the past couple of years into tropical cyclones to add to the growing list that invents a new metric to try and prove a causal link between what are relatively small rises in sea temperatures over recent decades to the frequency, longevity, faster intensification, slower movement and now slower decay of tropical cyclones.
- Probability of hurricanes reaching category 3 has increased decade after decade
- Tropical cyclones intensifying more quickly
- Hurricanes have grown stronger since 1979
- Frequency of major hurricanes increased by 330% in a century
- Tropical cyclones taking longer to develop into hurricanes
- Atlantic hurricanes slowing down
I see that Chakraborty says that this slowness to decay might be due to the increased ‘moisture’ content of hurricanes these days, which makes sense. How they are going to come up with some kind of estimate of the moisture content of each tropical cyclone seems fraught with difficulties. There seems to be no end to these studies and new metrics from scientists in lockdown, as they search in a vain to find the holy grail or the master ring which proves a definitive link between warmer seas and these various increases. That’s because they can’t factor in (or factor out) the rapid advances in technology which means that tropical cyclones today are under greater forensic like scrutiny than ever before, and will certainly skew any results their study will find global warming’s way. To any skeptic the only thing a study which compares the 1970’s with today will prove, is just how much technology has advanced in the last 50 years. Perhaps when the NHC have collected more data in the coming decades, and we can compare like for like, the link between the two will become clearer, but until then at least for me the jury is still out.