13 November 2017 - HURRICANE KATRINA

HURRICANE 

KATRINA

G'day folks,

As I write  this, Texas is going through similar problems.

Early in the morning on August 29, 2005, Hurricane Katrina struck the Gulf Coast of the United States. When the storm made landfall, it had a Category 3 rating on the Saffir-Simpson Hurricane Scale–it brought sustained winds of 100–140 miles per hour–and stretched some 400 miles across. The storm itself did a great deal of damage, but its aftermath was catastrophic. Levee breaches led to massive flooding, and many people charged that the federal government was slow to meet the needs of the people affected by the storm. Hundreds of thousands of people in Louisiana, Mississippi and Alabama were displaced from their homes, and experts estimate that Katrina caused more than $100 billion in damage.

Hurricane Katrina: Before the Storm 

The tropical depression that became Hurricane Katrina formed over the Bahamas on August 23, 2005, and meteorologists were soon able to warn people in the Gulf Coast states that a major storm was on its way. By August 28, evacuations were underway across the region. That day, the National Weather Service predicted that after the storm hit, “most of the [Gulf Coast] area will be uninhabitable for weeks…perhaps longer.”

New Orleans was at particular risk. Though about half the city actually lies above sea level, its average elevation is about six feet below sea level–and it is completely surrounded by water. Over the course of the 20th century, the Army Corps of Engineers had built a system of levees and seawalls to keep the city from flooding. 

The levees along the Mississippi River were strong and sturdy, but the ones built to hold back Lake Pontchartrain, Lake Borgne and the waterlogged swamps and marshes to the city’s east and west were much less reliable. Before the storm, officials worried that surge could overtop some levees and cause short-term flooding, but no one predicted levees might collapse below design height. Neighborhoods that sat below sea level, many of which housed the city’s poorest and most vulnerable people, were at great risk of flooding.

 The day before Katrina hit, New Orleans Mayor Ray Nagin issued the city’s first-ever mandatory evacuation order. He also declared that the Superdome, a stadium located on relatively high ground near downtown, would serve as a “shelter of last resort” for people who could not leave the city. (For example, some 112,000 of New Orleans’ nearly 500,000 people did not have access to a car.) By nightfall, almost 80 percent of the city’s population had evacuated. Some 10,000 had sought shelter in the Superdome, while tens of thousands of others chose to wait out the storm at home.

Hurricane Katrina: Storm and Flooding 

By the time Hurricane Katrina struck New Orleans early in the morning on Monday, August 29, it had already been raining heavily for hours. When the storm surge (as high as 9 meters in some places) arrived, it overwhelmed many of the city’s unstable levees and drainage canals. Water seeped through the soil underneath some levees and swept others away altogether. By 9 a.m., low-lying places like St. Bernard Parish and the Ninth Ward were under so much water that people had to scramble to attics and rooftops for safety. Eventually, nearly 80 percent of the city was under some quantity of water.

Hurricane Katrina: The Aftermath 

Many people acted heroically in the aftermath of Hurricane Katrina. The Coast Guard, for instance, rescued some 34,000 people in New Orleans alone, and many ordinary citizens commandeered boats, offered food and shelter, and did whatever else they could to help their neighbors. Yet the government–particularly the federal government–seemed unprepared for the disaster. The Federal Emergency Management Agency (FEMA) took days to establish operations in New Orleans, and even then did not seem to have a sound plan of action. Officials, even including President George W. Bush, seemed unaware of just how bad things were in New Orleans and elsewhere: how many people were stranded or missing; how many homes and businesses had been damaged; how much food, water and aid was needed. Katrina had left in her wake what one reporter called a “total disaster zone” where people were “getting absolutely desperate.”

(For one thing, many had nowhere to go. At the Superdome in New Orleans, where supplies had been limited to begin with, officials accepted 15,000 more refugees from the storm on Monday before locking the doors. City leaders had no real plan for anyone else. Tens of thousands of people desperate for food, water and shelter broke into the Ernest N. Morial Convention Center complex, but they found nothing there but chaos. Meanwhile, it was nearly impossible to leave New Orleans: Poor people especially, without cars or anyplace else to go, were stuck. For instance, some people tried to walk over the Crescent City Connector bridge to the nearby suburb of Gretna, but police officers with shotguns forced them to turn back.)

Katrina pummeled huge parts of Louisiana, Mississippi and Alabama, but the desperation was most concentrated in New Orleans. Before the storm, the city’s population was mostly black (about 67 percent); moreover, nearly 30 percent of its people lived in poverty. Katrina exacerbated these conditions, and left many of New Orleans’s poorest citizens even more vulnerable than they had been before the storm.

In all, Hurricane Katrina killed nearly 2,000 people and affected some 90,000 square miles of the United States. Hundreds of thousands of evacuees scattered far and wide. Today, after years of recovery and rebuilding efforts, people along the Gulf Coast have made great strides in returning to life as usual even as they continue to rebuild.

   

Clancy's comment: Mm ... Not good. Australia also has massive floods.

I'm ...

 

13 September 2016 - TORNADOES

TORNADOES

G'day folks,

Many of my American friends will relate to this post. So, what is a tornado? A tornado is a violently rotating column of air that rotates while in contact with both the surface of the Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud.

Although tornadoes can happen at any time of year, they are especially common during the spring and early summer. May and June are the peak months in terms of numbers of tornadoes, but April appears to be the deadliest month. Two of the all-time worst tornado disasters occurred in April. On April 3-4, 1974, 148 twisters struck 13 states, causing more than 300 deaths, and on April 27, 2011, 137 reported tornadoes swept through the south, killing nearly 300 people in six states. Most of the fatalities occurred in Alabama. May holds the record for experiencing the most tornadoes. In May 2003, there were 543 recorded tornadoes. On average, 60 people die each year as a result of tornadoes, mostly from flying and falling debris. 

What Is a Tornado?

A tornado is a dark funnel-shaped cloud made up of violently rotating winds that can reach speeds of up to 300 m.p.h. The diameter of a tornado can vary between a few feet and a mile, and its track can extend from less than a mile to several hundred miles. Tornadoes generally travel in a northeast direction (depending on the prevailing winds) at speeds ranging from 20-60 m.p.h.

 What Causes a Tornado?

 

Tornadoes are most often spawned by giant thunderstorms known as "supercells." These powerful, highly organized storms form when warm, moist air along the ground rushes upward, meeting cooler, drier air. As the rising warm air cools, the moisture it carries condenses, forming a massive thundercloud, sometimes growing to as much as 50,000 ft. in height. Variable winds at different levels of the atmosphere feed the updraft and cause the formation of the tornado's characteristic funnel shape.

 Where Do Tornadoes Occur?

 

The conditions that lead to the formation of tornadoes are most often met in the central and southern U.S., where warm, humid air from the Gulf of Mexico collides with cool, dry air from the Rockies and Canada. This area, dubbed "tornado alley," extends roughly from the Rocky Mountains to the Appalachians, and from Iowa and Nebraska to the Gulf of Mexico. Tornadoes can also occur elsewhere, though, including all U.S. states, Europe, Asia, and Australia.

What Kind of Destruction Do Tornadoes Cause?

The Fujita scale classifies tornadoes according to the damage they cause. Almost half of all tornadoes fall into the F1 or "moderate damage" category. These tornadoes reach speeds of 73-112 m.p.h. and can overturn automobiles and mobile homes, rip off the roofs of houses, and uproot trees. Only about 1 percent of tornadoes are classified as F5, causing "incredible damage." With wind speeds in excess of 261 m.p.h., these tornadoes are capable of lifting houses off their foundations and hurling them considerable distances.

 

Clancy's comment: It sounds crazy, but I'd love to be up close and personal  so I could take some good photographs.

I'm ...