Last Fall, I wrote a Katrina online activity entitled, Hurricane Katrina: A Citizen Resource. This citizen resource is designed to help us understand the magnitude of this natural disaster, and to point us toward ways to reduce the destruction and loss of life caused by natural disasters. Nearly 3,000 visitors have made use of the Hurricane Katrina site.
Image: The Path of Katrina
One of the most important documents regarding what we knew about the potoential effect of a Category 4 or 5 Hurricane on New Orleans was documented in an article Washing Away published in 2002 by the Times-Picayune Newspaper. The Pulitzer Prize winning article was written by John McQuaid and Mark Schleifsten.
I want to update readers of the blog, and those who have visited the Hurricane Katrina website that McQuaid and Schleifsten published a book, Path of Destruction: The Devastation of New Orleans and the Coming Age of Superstorms..
What is powerful about this book is the scientific and historical context that the authors describe by providing a vivid exploration of the relationship between hurricanes and the location of New Orleans, from the Native Americans that inhabited the area as far back as 900 AD, and the French who built the city in the middle of a swamp. The authors, who provided a documented warning of the effects of a superstorm years before Katrina explore the aftermath of Katrina, as well the scientific relationship between intense hurricanes and global warming.
If you live in Florida, one word you don’t want to hear on the evening news is “hurricane.” I lived in Florida in 1972 and 1975, and I don’t recall a concern about hurricanes. But now, friends that I have that do live in Florida have been affected for the past two-three years by the devastation brought on by very powerful hurricane seasons. What can hurricanes teach us about climate change? How can teachers inform their students of changes that many scientists think are occuring to the earth’s climates?
There are at least two schools of thought concerning climate change. Some scientists think that the increase in the number and intensity of hurricanes is part of a natural cycle of ebb and flow, and that we are in the midst of part of the cycle that followed a period of decreased hurricane intensity. They say that the earth’s climates have changed through time, with periods of colder weather following warmer weather, increased hurricane intensity followed by an ebb in intensity, and so forth. One scientist at Colorado State University who doesn’t accept the concept of global warming, but rather sees natural cycles at work is Prof. Bill Gray. Gray is known as one of the most famous weather predicters but feels that global warming is a hoax.
A second school of thought claims that the burning of coal and other fossil fuels has released enormous amounts of carbon dioxide gas into the atmosphere, causing a warming trend since 1860. Not only has the atmosphere heated up, but so has the land surface and surface water temperatures of the oceans. It’s the increased surface water temperatures that has interested climate scientists who study hurricanes because hurricanes “feed” or get their energy from warm ocean water. Increase the water temperature, and you have provided additional energy resulting in increased numbers and more intense hurricanes, they say.
Research done at Georgia Institute of Technology and reported elsewhere supports the second claim. Studying hurricanes from the period 1970 to 2004, researchers found that the number of category 4 and 5 hurricanes has more than doubled after 1990. This is shown in the graph below.
Hurricane Katrina is an example of one of the most powerful hurricanes to affect the United States. After the hurricane, I developed a Katrina website as a resource for teachers to use help inform their students of hurricanes in general, and Katrina specifically.
The hurricane season has begun with Alberto, which fortunately weakened after it nearly reached hurricane winds. But it the season wake-up call for coastal citizens, and those of us inland that another season is apon us. Some are predicting an intense season.
No. That’s the short answer. No one factor causes hurricanes, cyclones or tornadoes. However, global warming, (especially the warming of ocean surface temperature) could contribute to an increase the frequency and intensity of hurricanes. Recent studies suggest that hurricane intensities (say more category 4 or 5 storms) may have increased. One scientist, Kerry Emanuel, published a report in Nature predicting that hurricane intensity should increase as global mean temperatures increase. Another report suggests that hurricanes will increase in intensity later in this century.
However, 2005 was one of the worst hurricane seasons ever (we ran out of names on the A-Z list, and had to go to Greek letters, alpha, beta, etc.) with 27 (that’s twenty-seven) hurricanes. And some very surprising things happened. Katrina moved across Florida as a Category 1-2 storm, causing great damage, and then once it entered the warm waters of the Gulf of Mexico, and raged into a Category 5 storm, and hit New Orleans as a very strong Category 4 storm, resulting in the destruction of levees, the flooding of a great part of the city, and eventual evacuation of more than 500,000 people.
A new hurricane season has arrived. The first tropical depression (Tropical Depression 1—it will become Alberto if its winds reach hurricane intensity). The depression formed west of Cuba, and could enter the Gulf and sweep across Florida and South Georgia.
I asked if global warming caused hurricanes. The answer is still no. But, global warming is viewed as contributing the increased intensity of hurricanes. Meterologists predict an active hurricane season. Could this be the result of global warming? I think the answer is probably yes.
The devastation of Hurricane Katrina was beyond belief, and might be the worst natural disaster in US history. Natural disasters, such as hurricanes, earthquakes, volcanic eruptions, floods, and other severe storms have impacted more than 2.2 billion people in the past 10 years. This is a very large increase from the previous ten years, and it will increase in the forseeable future. It is isn’t that there are more hurricanes or earthquakes, it is that people have continued to populate high risk areas, and in many cases, not take the precautions that might lessen the effect of these natural events. For example, in the case of the flooding of New Orleans, the THE TIMES-PICAYUNE Newspaper wrote a five-part series on the effect of a hurricane on New Orleans in 2002. It was a clear warning of what would happen to New Orleans in the event of a category 4 or 5 hurricane. The response of federal and state agencies has been considered by many as “unacceptable” and has led to a great deal of criticism.
I have developed a citizen resource (in the form of a webquest) that is designed to educate and inform people about Hurricane Katrina. Teachers should find the resource valuable for upper elementary, middle and high school students.