by The Green Hornet
It’s that time of year again. Yup, hurricane season has started officially. The media is cluttered with warning; hurricane kits abound; committees have been formed, our hurricane response has been streamlined and modified based on our experiences with Ivan.
On the radio comes the reassuring voice of the Leader of Government Business, Hon. Kurt Tibbetts, followed shortly thereafter by His Excellency the Governor Stuart Jack. Lines of communication have been opened with the international media, and with the U.K. government. If there is a next time – and hopefully there won’t be – then we won’t pretend nothing bad has happened and keep out the international media and refuse international aid. Like we did last time around.
Should we be worried? Well, I’m afraid so.
The latest 2006 Atlantic hurricane season forecast from the veteran forecast team at Colorado State University (CSU) was issued last week – that’s from hurricane guru Dr. Bill Gray and his buddy Phil Klotzbach. Their forecast is unchanged from their earlier April 4 and December 6 forecasts, predicting 17 named storms (10 is average), nine hurricanes (six is average), and five intense hurricanes (2.3 is average). This is the highest level of activity they have forecast in their 23 years of making these predictions.
They put the odds of a major (Category 3-4-5) hurricane crossing the U.S. coast at 82% (the average for last century is 52%). The U.S. East Coast (including Florida) has a 69% chance of a major hurricane strike (31% is average), and the Gulf Coast, 38% (30% is average). In addition, there is an above-average risk of major hurricanes in the Caribbean.
The CSU team identified four years that had similar weather patterns in May compared to this year, and all four of these years had much higher than usuak levels of hurricane activity: 2004 (six major hurricanes, three of which made landfall in the U.S.); 2001 (no hurricanes made landfall in the U.S., but there were two major hurricanes); 1996 (six major hurricanes, one of which hit the U.S. – Fran); and 1961 (seven major hurricanes, one of which hit the U.S.– Carla).
So what about the other guys? What are the other hurricane forecasting groups are predicting for 2006?
The NOAA forecast issued May 22, 2006: 13–16 named storms, 8–10 hurricanes and 4–6 intense hurricanes. Cuba’s National Weather Institute prediction from May 2, 2006: 15 named storms and 9 hurricanes. Finally, Tropical Storm Risk, Inc.’s May 5, 2006 forecast: 15 named storms and 8 hurricanes.
The warming cycle continues
The Colorado State University forecasters cite three main reasons to expect a very busy season:
1) Weaker trade winds than usual have led to abnormal warming of the tropical Atlantic since the early part of April. Sea surface temperatures remain much warmer than average, and are expected to be much warmer than average during the August-October peak of hurricane season.
2) No El Niño is expected to be present during August-October 2006. When the tropical Atlantic is warm and no El Niño is present, Atlantic basin hurricane activity is greatly enhanced.
3) We continue to be in the positive phase of the Atlantic Multidecadal Oscillation (AMO), the decades-long cycle of natural hurricane activity.
In other words, global warming continues on its merry way and the conditions that feed the storms keep on getting more favourable.
At the same time a fascinating story appeared on the BBC. Its science reporter, Rebecca Morelle reports that the results of analysis of a sediment core excavated from 400 meters (1,300feet) below the seabed of the Arctic Ocean have enabled scientists to delve far back into the region’s past.
Three papers published in the journal Nature reveal that an international team of scientists has been able to pin-point the changes that occurred as the Arctic transformed from green house to ice house – 55 million years ago. At that time, the authors report, the North Pole was an ice-free zone with tropical temperatures – just imagine what today’s tropics were like then!
Until now, our understanding of the Arctic’s environmental history has been limited because of the difficulties in retrieving material from the harsh, ice-covered region, the story continues.
But in 2004, the Arctic Coring Expedition (Acex) used ice-breaking ships and a floating drilling rig to remove 400 meter long cylinders of sediment from the bottom of the ocean floor. The cores were taken from the Lomonosov Ridge, which stretches between Siberia and Greenland.
Core reveals Arctic’s tropical phase
The core holds layer upon layer of compressed fossils and minerals, which when studied can tell the story of millions of years of the Arctic’s history, Ms. Morelle explains. The bottom or deepest end of the cylinder helped scientists to uncover what had happened to the Arctic during a dramatic global event known as the Palaeocene/Eocene Thermal Maximum, which took place about 55 million years ago.
“This time period is associated with a very enhanced green house effect,” explained Dr. Appy Sluijs, a palaeoecologist from Utrecht University in the Netherlands and the lead author on one of the papers. “Basically, it looks like the Earth released a gigantic fart of green house gases into the atmosphere – and globally the Earth warmed by about 5C (9F),” he continued. “This event is already widely studied over the whole planet – but the one big exception was the Arctic Ocean.”
The core revealed that before 55 million years ago, the surface waters of the Arctic Ocean were ice-free and as warm as 18C (64F). But the sudden increase in greenhouse gases boosted them to a balmy 24C (75F) and the waters suddenly filled with a tropical algae.
And here’s the cruncher – when current climate models were applied to this period of the Earth’s history, said Dr Sluijs, they predict North Pole temperatures to be about 15C (27F) lower than the core shows.
The second of the three papers, led by paleaoecologist Henk Brinkhuis, also from Utrecht University, reports that the Arctic Ocean underwent another transformation about 50 million years ago, the BBC story continues. The water changed from salty to fresh, and the ocean became covered with a thick layer of freshwater fern, called Azolla.
“We assume from climate models from the early Eocene Period that there was lots of fresh water coming into the basin via precipitation and giant Canadian and Siberian river run-offs,” said Professor Brinkhuis. “And at a certain point this gave rise to this whopping great growth of Azolla .”
He believes the prolific growth of this fern may be linked to the later drops in temperature in the area. “When you have so much of this plant in this giant sea you have a mechanism to pump out carbon dioxide from the atmosphere. It is sort of an anti-green house effect,” he said. “We argue that this sits right on the break from the really warm hot house period into the time when the ice house begins.”
Further up the core – 500,000 years above where the Azolla was found – the researchers found the first drop stones, explained Professor Brinkhuis, who is also a co-author on the third paper which details Arctic ice-formation. “These are little stones that come from icebergs, ice sheets or sea ice. So it must have been cold enough to have ice.
Data needs to be revisited
“Before we did this it was thought that the ice field in the Northern hemisphere only began about three million years ago, but now we have pushed that back to 45 million years ago.”
Although the data tells us how the world changed from one with green house conditions to one with ice house conditions millions of years ago it may also help scientists to predict what will result from the present changes in climate, the story concludes.
Dr Sluijs points out that the data reveals that some of the climate models used to detail the Arctic’s history got things wrong, and as they are the same models that predict our future climate they may need adjusting.
Kate Moran, lead author of one the papers and professor of oceanography and ocean engineering at University of Rhode Island, agrees: “We anticipate that our data will be used by climate modellers to give us better information about how climate change occurs and possibly where global climate might be leading,” she said. “Today’s warming of the Arctic can, in all likelihood, be attributed to mankind’s impact on the planet, but as our data suggest, natural processes operating in the past have also resulted in a significant warming and cooling of the Arctic.”
The Acex arctic core revelations show that we are continually learning about our planet. They also reveal what the arctic was like when the planet was hot, hot, hot. Certainly it’s not that hot now, but it is getting a whole lot warmer, and we need to know what things were like when it was much hotter. Information we can find out through such activities as the artic core project.
We do know that 55 million years ago storms raged around the planet that make our current hurricanes look puny. That’s something to think about as we prepare for the worst during the next six months. It’s also something to think about when we see buildings on the beach being rebuilt from Ivan’s wrath to be exactly the same as they were before the storm hit, with some newer buildings even closer to the sea.
I guess we just don’t learn all our lessons at the same time.
If you wish to contact the Green Hornet directly, you can e-mail me at: caymanhornet@yahoo.com. All messages will be treated confidentially.
