2015 was an interesting year for tropical cyclones. Hurricane Joaquim, Hurricane Patricia, and Tropical Cyclone Chapala were each significant in comparison to past cyclones.
Joaquim developed in the Atlantic and moved toward the Bahamas, where it caused extensive damage. Although Joaquim was not a particularly unusual storm, it was notable for its strength. It wind speeds of 155 mph made it a Category Four hurricane, the strongest hurricane the Atlantic had produced since Hurricane Igor in 2010. The last Category Five hurricane to form in the Atlantic Basin was Hurricane Felix in 2007. Another notable feature of Joaquim was its formation late in the season; it hit the Bahamas in October, which is the latest a Category Four or stronger hurricane has hit that area since 1932.
Patricia, a Category Five hurricane, was even more notable for its strength, breaking multiple records. Its highest wind speed was clocked at 215 mph, which made it the strongest hurricane ever recorded in the east Pacific and Atlantic Basin. This makes it the strongest hurricane period, though there have been typhoons that have been stronger. Tropical cyclones are also measured by pressure, lower pressure generally equating to more intense storms. Patricia had the second lowest pressure every recorded by any storm, only beat out by Typhoon Tip in 1979. Lastly, Patricia had winds that maintained a speed of 200 mph for over a minute. This means Patricia had the highest sustained wind speed of any storm ever recorded on the planet, breaking the record of Typhoon Haiyan in 2013.
Patricia touched down in Mexico. While it caused extensive flooding, the area was mostly rural, which resulted in less devastation than had it touched down somewhere extensively populated. The storm also dissipated quickly, though flooding occurred throughout Mexico and South Texas.
Cyclone Chapala was unusual due to its location. It developed into a Category Four storm in the Arabian Sea, the strongest storm ever recorded there. When it hit Yemen it was a Category One storm, the strongest storm to have hit Yemen in over 50 years. Chapala caused two to seven times the yearly rainfall to occur in a single day, causing significant damage. Since the area typically gets so little rain, the infrastructure of affected towns and villages were not built to withstand this kind of flooding, which contributed to the devastation.
Multiple factors contributed to this particular hurricane season, and it is important not to ascribe a single factor as explanation for these occurrences. For instance, climate change is such a slow and incremental process that to claim Chapala is solely a result of climate change would be scientifically inaccurate. However, because warm waters drive these storms and a heat trapped by carbon dioxide will eventually result in warmer waters, scientists do predict that climate change will contribute to creating more violent storms. Another factor that contributed to this hurricane season is the fact that 2015 was an El Nino year, meaning warmer temperatures and more rain in certain parts of the globe.
