EARTH 108 Lecture Notes - Lecture 9: Wind Shear, Landfall, Hurricane Hanna (2008)

• School: U of M
• Department: Earth and Environmental Sciences
• Course: EARTH 108
• Professor: Eric Hetland

Document Summary

Lecture outline: forecasting cyclone paths, cyclone (early) warning, responding to warning (more in l11, hurricanes & climate, global warming, el ni o & la ni a, north atlantic oscillation. Hurricane hanna in 2008: there was a forecast to remain category 1 and make land-fall around 8am on friday, but it quickly degraded into a tropical depression by the next morning. However, the hurricane made landfall earlier than expected. There were 7 deaths and losses of million. Two of the conditions that dictate a cyclones fate are: North atlantic hurricanes appear to be becoming more intense as the sea surface temperature increases. Under el nino conditions, there is low risk of hurricanes. Under la nina conditions, there is high risk of hurricanes. When the north atlantic oscillation is positive there are stronger trade winds polar jet stream more direct cooler seas off africa. Cooler off e. us always expect the unexpected.