As cyclone Darius approached Mauritius, it produced spectacular colored sunsets.
Photo : Verity Steptoe
January 13, 2004
Preparing for Cyclone Darius
This is Odyssey science intern, Verity Steptoe, speaking to you from Mauritius in the aftermath of a tropical cyclone that bore down upon the tiny oceanic island nation situated in the southwest Indian Ocean.
On December 31st, 2003 as people around the world prepared for a night of celebration, the crew welcomed the new year by preparing the Odyssey for the fury of a cyclone named Darius, scheduled to pass through Mauritius in the first few days of 2004.
In the Indian Ocean, tropical storms originate between latitudes 5° - 13°, spinning to the south in the Southern Hemisphere, and to the north in the Northern Hemisphere. On average, there are 11 tropical storms and 4 cyclones a year in this region of the Indian Ocean. The peak season for cyclones is between the months of December to March. Tropical cyclones in the southern Indian Ocean generally form as a result of a combination of different weather conditions. First, sea surface temperatures are generally above 26° C. Increasing convection around the equator at the area of convergence of Southern and Northern Hemisphere weather systems, results in humid, warm air rising and cooling to form large thunder clouds. Cooler air replaces the displaced warm air causing wind speeds to pick up and to begin to spiral (clockwise in the Southern Hemisphere, anti-clockwise in the Northern Hemisphere) around a low-pressure area.
As a cyclone advances, it is preceded by characteristic changes in weather. The wind speed increases in severity, occasionally reaching gusts of over 100 knots. The skies open up with bouts of torrential rain and the ocean surface swells, bucking and rising in response to the power of the wind. Atmospheric pressure starts to decrease, dropping more rapidly as the cyclone draws closer.
In the southwest Indian Ocean, tropical cyclones are described as tropical storms where estimated wind gusts range from 64 - 130 knots. The cyclone warning system in Mauritius is as follows: A Class One warning is issued 36 - 48 hours before the advent of cyclonic conditions; Class Two, when there are approximately 12 hours of daylight prior to predicted wind gusts of 64 knots; Class Three, issued to allow 6 hours of daylight prior to estimated wind gusts up to 64 knots and; Class Four, when gusts of 64 knots are observed and are expected to continue. Understanding the behavior of cyclones in these waters, the Odyssey crew, with great trepidation, tracked the movements of Darius as she moved southwards towards Mauritius.
The following is an account leading up to Darius.
December 29, 2003 - Monday:
1pm - Darius first came to our attention on the afternoon of Monday, December 29th, during the crew's regular monitoring of weather reports in the Southern Indian Ocean. The first official warning was posted on the US Navy meteorology website regarding a tropical cyclone, located 700 nautical miles, northeast of Mauritius and advancing in our general direction.
December 30, 2003 - Tuesday:
10am - Darius does not yet pose an immediate threat to Mauritius, located 495 nautical miles, north/northeast of Mauritius and tracking in a southwesterly direction at a speed of 13 miles per hour. Currently wind gusts are reaching 50 knots, with average wind speeds of 35 - 45 knots. Wave heights around Darius are up to 18 feet.
December 31, 2003 - Wednesday:
10am - Darius is 300 nautical miles, northeast of Mauritius and tracking southwest direction at 7 miles per hour. Current maximum sustained winds speeds are 45 - 55 knots with gusts over 70 knots. Wave height around Darius is peaking at 18 ft. Warnings and updates on Darius's impending movements are now regularly broadcast on marine radios aboard all boats in Mauritian waters.
12am - The Odyssey crew face a dilemma. We need to move from our present location to more suitable one, where she will be protected from strong winds and accompanying high swells that Darius may unleash.
While the Odyssey's neighbors, an eclectic collection of pleasure yachts from Reunion and France, recreational sport fishermen, and tourist charter catamarans, scatter to the safety of shallower waters, the Odyssey is limited in her options.
One designated safe area in Port Louis harbour has a maximum water depth of 3 meters, unsuitable for the Odyssey, with a draft of 3.5 meters.
Bob Wallace boards up the windows of the Odyssey to prepare for the coming cyclone.
Photo : Verity Steptoe
After an anxious 2 hour wait, an appropriate location was found, still within Port Louis harbour. We were directed to where large long-line tuna fishing boats were moored, with sufficient water depth. We are currently sandwiched between a raft of three Taiwanese long liners, and a large catamaran.
You may wonder how the crew prepares a ship for potentially dangerous weather conditions such as a tropical cyclone?
First, we need to reach safe ground. Special reinforcements are required. We have 3 bow lines, 2 bow springs, 2 stern springs and 2 stern lines attaching us to our nearest neighbour, a 125 foot long liner fishing vessel. Hopefully these will hold us.
Our second task is to tie down everything that could potentially become a lethal flying object. The zodiac, small dinghy and kayak are securely attached to the deck and loose objects safely stored in the holds below.
Next, we have to protect the windows from flying debris. It was my job to securely fasten the porthole covers in the cabins, while other crewmembers screwed storm boards to the many windows of the Odyssey.
3pm - A few days prior, the crew had been invited to spend the evening at a popular tourist location on the island, to welcome in the new year. It was with much disappointment that we had to cancel but it was necessary to stay onboard the boat to ensure its safety.
10pm - Weather update! Darius is now 290 nautical miles, north/northeast of Mauritius. She is heading south/southwest at 5 knots. Her wind speeds are increasing, at 55 - 65 knots, with gusts of 80 knots and wave height over 23 feet. Darius's intensity is estimated to peak in 48 hours, just after dinner on the 2nd January 2004. We are still uncertain how close she will pass the Mauritius coastline and the crew waits patiently with bated breath.
January 1, 2004 - Thursday:
12am - Happy New Year! We emerge from the salon to witness a spectacular fireworks display!
Everywhere we look there are large sparkling colourful bursts of light, illuminating the sky.
10am - After a long night on 2 hour watch shifts, we arose in the New Year to find Darius was 220 nautical miles, north/northeast of Mauritius.
4pm - Darius has just been officially upgraded to a Class 2 cyclone, with wind speeds around 70 - 85 knots. She is now only 180 nautical miles, north/northeast of Mauritius. Her projected trajectory is to track south and pass approximately 56 NM to the east of the island. Fortunately, this means Mauritius will escape the full impact of Darius.
5pm - Some crew members jump in the Zodiac to survey the harbour and get an estimate on the number of boats using Port Louis as a safe haven.
In a small area, close to our original mooring, we count over 100 boats. It's starting to get a little crowded in here.
One consolation to being in the pathway of a cyclone, are the amazing sunsets. The sun setting over the billowing clouds creates the most fantastic portrait of an explosion of colours: shades of yellow, orange, red, pink and purple! Photographs do not do the view any justice!
7pm - Three large fishing boats have entered our sanctuary, directed by 2 tug boats alongside a row of 2 other similar sized fishing boats. Not sure if any more boats can fit as every available space in the harbour appears to now be occupied.
9pm - The cyclone is coming and the rain has commenced. There is little wind in the harbour so the heavy rain falls vertically onto the deck and streams over the sides to cascade into the murky harbor water. Darius is 140 nautical miles away.
Odyssey is tied up alongside fishing boats and pleasure craft awaiting the arrival of Darius.
Photo : Verity Steptoe
All throughout the day there has been palpable electricity in the air, with boats united in their anxious and long wait for the cyclone to pass. How close will she get to Mauritius? How strong will the winds be? Is my boat fully prepared? It is no different aboard the Odyssey. Despite several offers from friends on land, all crew members are staying aboard. If we thought the winds were to exceed 70 - 80 knots, we would likely vacate the boat and head ashore but there has been no evidence so far to suggest this, so we elect to sit tight. In addition, there is increasing evidence that Darius is gradually decreasing in intensity over time.
January 2, 2004 - Friday:
4am - The atmospheric pressure is still dropping and currently hovers around 1005 Mb (Millibars).
In the center of Darius, the pressure is 980 Mb so we know she is drawing closer, traveling south, 96 nautical miles north/northeast of Mauritius.
10am - Darius is currently 78 nautical miles, northeast of Mauritius.
2pm - Barometric reading: 1001.9 Mb, and still dropping.
4pm - Barometric reading: 1000 Mb.
5pm - Barometric reading: 999 Mb. Darius is 44 nautical miles from us and has just been categorized as a Class 3 cyclone, with wind gusts up to 66 knots.
1am - The cyclone has passed. About 1000 houses on the east coast of Mauritius lost power, while those houses most exposed to the full force of the cyclone and subjected to winds around 60 knots were severely damaged. Fortunately we experienced winds no greater than 30 knots, and minimal swell while safely nestled in Port Louis harbor. After the long hours waiting and tracking the cyclone, the entire episode was rather anti-climatic but we are relieved there was no injury to the crew or damage to the boat.
3pm - With the passing of the cyclonic system, the atmospheric pressure has slowly increased over the past few hours to reach 1007.7 Mb. We have returned to our original mooring and this is where we will stay until we depart Mauritius late next week.
After the (anti) climax of Darius, the main focus of the Odyssey crew is to prepare for our upcoming passage to the Maldives. We must obtain sufficient fuel and food provisions for the two-week passage. After saying goodbye to new friends, we will travel as fast as possible to get north of 5° south, to escape the threat of future cyclones in the region. Once in the Maldives we will join other crew members, before recommencing our quest for sperm whales.
Log written by Verity Steptoe.