NOAA-led research results indicate that the average latitude where tropical cyclones achieve maximum intensity has been shifting poleward since 1980, briefs the NOAA.
Over the past 30 years, the location where tropical cyclones reach maximum intensity has been shifting toward the poles in both the northern and southern hemispheres at a rate of about 35 miles, or one-half a degree of latitude, per decade according to a new study, 'The Poleward Migration of the Location of Tropical Cyclone Maximum Intensity', that NOAA inform is to be published in Nature.
As tropical cyclones move into higher latitudes, some regions closer to the equator may experience reduced risk, while coastal populations and infrastructure poleward of the tropics may experience increased risk. With their devastating winds and flooding, tropical cyclones can especially endanger coastal cities not adequately prepared for them. Additionally, regions in the tropics that depend on cyclones' rainfall to help replenish water resources may be at risk for lower water availability as the storms migrate away from them.
Researchers explain that the amount of poleward migration varies by region. The greatest migration is found in the northern and southern Pacific and South Indian Oceans, but there is no evidence that the peak intensity of Atlantic hurricanes has migrated poleward in the past 30 years.
By using the locations where tropical cyclones reach their maximum intensity, the scientists have high confidence in their results.
"Now that we see this clear trend, it is crucial that we understand what has caused it - so we can understand what is likely to occur in the years and decades to come," says Gabriel Vecchi, scientist at NOAA's Geophysical Fluid Dynamics Laboratory and co-author of the study.