Saturday, July 2, 2011

Tempestuous Weather Returning; a Hurricane Question and Answer Guide

Helicopter Arrival on Western Regent; Gulf of Mexico: Polar Sea 07.2008

I had arrived safely onboard the Western Regent and was thrilled to be on a hard surface in the middle of the vast ocean. I walked up two flights of stairs to reach the conference room, where most of my crew members were already waiting. I peaked around the corner to ask a young gentleman in a fire suit, “How long we were going to be in the conference room before we mobilize to the Polar Sea?”

He responded, “It will be another hour or possibly longer; we are waiting for the seas to calm down. Shortly after this, then we can launch the Fire Rescue Craft (FRC) to drop you and your crew off at the Polar Sea.”

When the gentlemen finished talking with me, he set out to fulfill his morning responsibilities. I chatted with a few of the guys for a few more minutes, until the captain of the ship came to greet us.

The Boys Coming Onboard Polar Sea; Gulf of Mexico 07.2008

The captain was a little bit shorter than me and had a small beard that seemed to fit the figure of his face. I could tell that he was pleased that we were onboard, even if it was only for a little while. He turned to my colleagues and me and asked, “Would you like to see the view from the bridge?” Of course, I automatically replied, “Most definitely!” He guided us up a few more flights of stairs to reach the bridge.

Close-view of Personnel in FRC; Gulf of Mexico 07.2008

Instantly I noticed how large the area was. I have never seen wings on the port (the left side of the ship) and starboard (the right side of the ship), where you can walk to the glass on either side and overlook the ocean right underneath your feet! This was a truly amazing experience.

Climbing Up Rope Ladder to Come Onboard Polar Sea; Gulf of Mexico 07.2008

As I was mesmerized into the waves below my feet, I heard my name being called out from behind me. I quickly turned around and recognized Jill and Carolyn, two best friends that accompanied me in a few courses that I took for my offshore training (HUET). Ironically, we have not seen each other for 6 months, but somehow in this moment we were standing on the same ship. We had a quick chat session and then I was summoned to leave.

The captain exclaimed, “The weather is getting rough; we need to get you off the boat before the seas get worse.” The boat had begun to violently rock back and forth; obviously, something big was about to happen.

The captain had arrangements for my crew and myself to quickly depart to the Polar Sea by the FRC; utilizing the FRC meant that we would be using the second method on how we are transferred to a project – “Embark to the Polar Sea; a Closer Approach to Hurricane Season.” The FRC made a mad dash twice to the Polar Sea to drop off the crew. Once onboard, my colleagues and I were requested to see the captain on the bridge.

Captain Brian of the Polar Sea; Gulf of Mexico: Polar Sea 07.2008

Captain Brian, a shaven-head and good-looking British gentleman peered around the corner of the ship’s office on the bridge. He emphasized, “The weather conditions are really increasing; additionally, there’s a hurricane that will be coming through our survey in the next few days.”

I had never seen a hurricane, let alone be in one! I was slightly nervous with this news, but I was reassured that we will be notified about the hurricane before it becomes a major threat. Though this statement made me feel a little better, I was still anxious about what was in store for the Polar Sea. 

Once I left the bridge, I had a few hours before I had to conduct visual observations of the marine mammals in the project area. Right after lunch, I had acquainted myself with the internet. I scanned articles about hurricanes and how one can define them.

I came across several sources that explained hurricanes more in depth. I spent a few extra minutes researching how warm the temperature had to be, what conditions sustain a hurricane, etc. I have included my findings below.

Meghan and I Photo Session; Gulf of Mexico: Polar Sea 07.2011

The Question and Answer Guide to Hurricanes:

1. What is a hurricane? A hurricane is a tropical cyclone with winds pushing 64 knots or greater.  In addition, they circulate counter-clockwise about their centers in the Northern Hemisphere. 

2. Where did the word “hurricane” originate from? Hurricane derived its name from ‘Hurican,’ who was the Carib god of evil. The legend has it that the Carib god ‘Hurican’ was derived from the Mayan god ‘Hurakan,’ one of their creator gods. This particular creator god blew his breath across the chaotic water and brought forth dry land. The breath reached the men, which destroyed their wood and summoned a great storm and flood.  

3. How are hurricanes formed?  Hurricanes are formed from simple complexes of thunderstorms. However, these thunderstorms can only grow to hurricane strength with cooperation from both the ocean and the atmosphere. First of all, the ocean water itself must be warmer than 26.5 degrees Celsius (81°F). The heat and moisture from this warm water is ultimately the source of energy for hurricanes. Hurricanes will weaken rapidly when they travel over land or colder ocean waters -- locations with insufficient heat and/or moisture. 

4. What factors have to be mixed together for a hurricane?  Hurricanes start over the ocean. Related to having warm ocean water, high relative humidities in the lower and middle troposphere are also required for hurricane development. These high humidities reduce the amount of evaporation in clouds and maximize the latent heat released because there is more precipitation. The concentration of latent heat is critical to driving the system.

The vertical wind shear in a tropical cyclone's environment is also important. Wind shear is defined as the amount of change in the wind's direction or speed with increasing altitude. Wind shear plays a role in hurricane formation.

When the wind shear is weak, the storms that are part of the cyclone grow vertically, and the latent heat from condensation is released into the air directly above the storm, aiding in development. When there is stronger wind shear, this means that the storms become more slanted and the latent heat release is dispersed over a much larger area.

Sea Surface Temperature Map - yellow, orange, and red colors show water temperatures warm enough to sustain hurricanes (> 26.5°C)

5. When is a hurricane categorized as a “hurricane”, and not a cyclone? When wind blows at least 74 miles per hour (mph), it is defined as a hurricane.  Hurricanes can destroy what they hit with violent force. When wind and water act as a team, then nothing can stand in its way; not even a house! The 5 classifications are on a scale 1 to 5; 1 being the less destructive force, while 5 is a critical situation developing.

  • Type 1 – Potential to move smaller objects; Slight damage
  • Type 2 – Ability to break windows and destroy trees, normally blowing at 100 mph; Moderate damage
  • Type 3 – Likely to break windows and doors; Moderate damage
  • Type 4 – Powerful enough to destroy homes; Severe damage
  • Type 5 – Force of energy blowing and flooding everything in its path; Severe damage

Category 5 on the Saffir-Simpson hurricane scale has no upper bound, on paper. But in theory, winds from a powerful hurricane could blow the scale out of the water, scientists say.  There is no such thing as a Category 6 storm, in part because once winds reach Category 5 status, it does not matter what we call it, this is very critical in whichever way you look at it.

The scale starts with a Category 1, which ranges from 74 to 95 mph. A Category 5 storm has winds of 156 mph or stronger. An extrapolation of the scale suggests that if a Category 6 were created, it would be in the range of 176-196 mph. Hurricane Wilma, in 2005, had top winds of 175 mph.

How much higher could hurricane winds blow? A hurricane gains strength by using warm water as fuel. With Earth's climate warming, oceans may grow warmer, too. And so, some scientists predict, hurricanes might become stronger. But physics dictates there must be a limit.

Based on ocean and atmospheric conditions on Earth nowadays, the estimated maximum potential for hurricanes is about 190 mph, according to a 1998 calculation by Kerry Emanuel, a climatologist at the Massachusetts Institute of Technology. This upper limit is not absolute; however, it can change as a result of changes in climate. Scientists predict that as global warming continues, the maximum potential hurricane intensity will go up. They disagree, however, on what the increase will be.

6. What are the parts of a hurricane?  

  • Eye – This is the center. It is also the calmest part of the storm
  • Eye Wall – This is located around the eye. This is the location where the strongest winds and rains are formed. The winds may blow 200 miles per hour in this area 
  • Rain Bands – These are the clouds that spin out and make the storm bigger

Three Parts in a Hurricane

7. When does hurricane season begin in the Atlantic? Additionally, what months have the most activity? Hurricane season in the Atlantic Basin, which includes the Caribbean and the Gulf of Mexico, officially runs June 1 to Nov. 30. There have been tropical storms and hurricanes before June 1 and after Nov. 30, but those are exceedingly rare.

"Usually the bulk of activity is in August through October," said Chris Landsea of NOAA's Atlantic Oceanographic & Meteorological Laboratory. "June and July are typically not good indicators for the rest of the season."

The reason hurricanes occur during these months is that they need warm water, which feeds a storm with energy, in order to form. For a hurricane to have enough energy to form and keep going, the water must be at least 80 degrees Fahrenheit (26.5 Celsius) down to at least 150 feet (50 meters), scientists estimate. The atmosphere must also be laden with moisture.

8. How do cyclones, hurricanes, and typhoons differ? Cyclone, typhoon and hurricane are all just different names for the same basic weather phenomenon. They are all powerful, spinning storms collectively called tropical cyclones, which form over warm tropical waters and reach sustained internal wind speeds of 74 miles per hour.

Hurricanes start in the Atlantic, Caribbean and northeast Pacific, while typhoons form in the western Pacific and southeastern Indian Ocean. If one of these monsters develops in certain parts of the Indian Ocean or part of the southwest Pacific Ocean, it goes by one of three variations of the generic term cyclone.

The storms are named according to seasonal lists kept by their respective basin's monitoring body. Typhoons and hurricanes and cyclones all rotate in the same direction, counterclockwise, if they form in the Northern Hemisphere.

So-called "backward" storms, which rotate clockwise, form in the Southern Hemisphere, though they are extremely rare in the Atlantic basin. Clockwise-rotating storms are more common in the Indian Ocean and off the coast of Australia, however.

After reading dozens of articles and researching further information on hurricanes, I had an in-depth conversation about hurricanes and the damage that they cause. I called my family and told them that a hurricane may interfere with our project. Ironically, my mother was already watching the news and following Hurricane Bertha’s every move across the Atlantic Ocean.

I reassured her that I would keep her updated on our ship’s position. That night as I laid my head down on my pillow, I thought about what I would do in the case of an emergency.

How would I react if a hurricane was approaching our ship? Would our ship act just in the nick of time? Or would our ship be destroyed by the monstrous waves and the violent winds? The situation will unravel itself, but I do hope that I am on the weather gods “good side.”

FRC Transfer to Polar Sea; Gulf of Mexico 07.2008