Intensity of Tropical Cyclones Shifting Poleward: New Study in Nature

Tropical expansion, most likely due to anthropogenic global warming, is causing hurricanes and cyclones to stray further from the equator in both hemispheres. The consequences of the Northward drift in the Americas and Asia could be huge as hurricanes and associated tropical storms will be more likely to hit the heavily populated US Eastern seaboard and high population coasts in China and Japan more often. New York better prepare for future storms like Sandy in other words.

According to the study, the latitude at which tropical cyclones reach their greatest intensity is gradually shifting from the tropics toward the poles at rates of about 33 to 39 miles per decade.

The new study was led by Jim Kossin, a National Oceanic and Atmospheric Administration (NOAA) National Climatic Data Center scientist stationed at the University of Wisconsin-Madison’s Cooperative Institute for Meteorological Satellite Studies.

The research documents a poleward migration of storm intensity in both the Northern and Southern Hemispheres through an analysis of 30 years of global historical tropical cyclone data.

More: Intensity of Tropical Cyclones Shifting Poleward: Study

More regarding this study from Andrew Freedman at Mashable:

The new study examines a metric known as a storm’s “lifetime-maximum intensity” during the period from 1982 to 2012, which is a timeframe that is not complicated by changes in storm observations. The metric refers to the point where storms max out in strength.

By examining storm data using this metric, the researchers found a strikingly apparent poleward shift in the locations where storms are reaching their peak intensity. Although the changes varied from ocean basin to ocean basin, with the greatest migration seen in the western North Pacific Ocean, which is the most active area for tropical cyclones, the shift was found in both the Northern and Southern Hemispheres.

In the Northern Hemisphere, the lifetime-maximum intensity point is moving north at 33 miles per decade, whereas in the Southern Hemisphere, that point is moving south at 39 miles per decade.

Also note that the full data set on storm tracks is here, however the earlier parts of last century’s data is less┬áreliable, which is why the paper is based on more recent storm data.