Chapters 12 & 13: Rocky Mountain Region and the Intermonte West

The Rocky Mountain Region and the Intermonte West area are in close proximity to one another and for purposes of this post will be compared with New Orleans in regards to the various natural hazards that threaten those regions.

The weather patterns in the Rocky Mountains and the Intermonte West make for very changeable weather. Winter storms can lead to flooding and avalanches. Spring and summer thunderstorms lead to crop and property damaging hail and potentially deadly lighting strikes.

 

 

New Orleans is considered part of the Coastal South.  This region is North America's most thunderstorm-prone area. Hurricanes are perhaps the climatic hazard that, since landfall of Katrina in 2005, are most brought to mind when New Orleans is mentioned.

 

New Orleans has a long history with damaging hurricanes.  Statistically, New Orleans is affected by a hurricane (either brushed or hit) every 2.24 years. The longest gap between storms was a 7 year period (1936-1944). The average number of years between direct hurricane hits ( hurricane force winds for a few hours) is once every 15.67 years. The average MPH of hurricane hits (based on sustained winds, not gusts) is 107 mph.  New Orleans was last affected by a hurricane on August 29th, 2012. Hurricane Isaac passed 45 miles to the southwest with 80 mph winds while moving slowly north/northwest causing surge flooding in surrounding areas with 5 dead in Louisiana.

 

Weather warning flag meanings:

 





Hurricane Katrina must be addressed when discussing natural hazards in regards to New Orleans.
An estimated 1,836 people died in the hurricane and the flooding that followed. Millions of people were left homeless along the Gulf Coast and in New Orleans, which experienced the highest death toll. According to the National Oceanic and Atmospheric Administration , Katrina was the most destructive storm to strike the United States. It ranks sixth overall in strength of recorded Atlantic hurricanes. It was also a very large storm; with, at its peak, maximum winds stretched 25 to 30 nautical miles and its extremely wide swath of hurricane force winds extended at least 75 nautical miles to the east from the center.

 Originally formed as a tropical depression over the Bahamas, it was a slow moving system. By the time it made its way to southern Florida Katrina was a moderate Category 1 hurricane. It weakened over land, but gathered strength once back out onto the Gulf of Mexico. It re-intensified as a Category Five storm with winds blowing at 175mph. As it turned to the Louisiana coast, it weakened to a Category 3 storm before making its second landfall along the Louisiana-Mississippi border on the morning of Aug. 29th.

Several levees in New Orleans collapsed and the city began to flood. Thousands sought refuge in the New Orleans Convention Center and the Superdome, which were overwhelmed. The National Guard was called in to help with evacuations.

Ultimately 80 percent of New Orleans and large portions of nearby parishes became flooded, and the flood waters did not recede for weeks. While many of the tourist areas such as the French Quarter have recovered, there are still neighborhoods just a short ride from the city where the effects of Katrina can still be seen.

Superdome Before and After

 

 



Levee and home NOLA Before and After

 

Photo sources: Google Images
Information Sources:
http://www.livescience.com/22522-hurricane-katrina-facts.html
http://www.hurricanecity.com/city/neworleans.htm
The Geography of North America: Environment/Culture/Economy Hardwick, Shelley, Holtgrieve