GEOLOGY & GEOPHYSICS
Ice data management system
improves Arctic operations
Terry Kennedy
ION Geophysical
Operators can now accurately pinpoint dangerous ice incursions
M
ore than 100 years ago when the Titanic struck an
iceberg and sank in the North Atlantic Ocean, the only
ice detection technologies available to the captain and
crew were visual sightings and wireless transmissions
in Morse Code from other vessels. Over time,
additional ice detection technologies have emerged to protect cruise
vessels and other commercial operations from the threat of sea
ice and icebergs. These include aerial photography, marine radar,
satellite imaging, infra-red cameras, weather bulletins, and sea ice
charts from government agencies and service providers.
With so much ice data available, the risk of a collision today
would seem remote. Nevertheless, in recent decades, collisions
with icebergs have occurred at a rate of more than two per year.
Why? More tourists are visiting Antarctica each year; a growing
number of commercial vessels take the Northern Sea Route across
the Russian Arctic to reduce time and fuel costs; and because the
US Geological Survey estimates that one-quarter of the planet’s
undiscovered but technically recoverable hydrocarbons lie above
the Arctic Circle. With the intensification of maritime activity in
ice-prone waters, the risk increases.
Narwhal’s display shows
a marine radar signal
with four icebergs approaching the vessel during the operator’s 2014
operations. Note the red
0.5 nm circular exclusion
zone and the green alert
zone.
The standard manual method used to display iceberg observations.
(All images courtesy ION Geophysical)
Even with many sources of ice data, a single piece of missing
or overlooked information can lead to a collision. In 2007, the MS
Explorer, an ice-reinforced cruise ship, sank in the Antarctic Ocean
due to a misjudgment. The captain and crew were experienced ice
navigators, but they underestimated the thickness and density of sea
ice they began to plow through one night. They mistakenly believed
that they were entering a thin first-year sea ice field and maintained
full speed. The vessel then struck a 15-ft (4.6-m) “wall” of older,
harder glacial ice that exceeded the Explorer’s ice classification,
slicing open the hull. The ship sank days later. All passengers and
crew were rescued safely.
One reason ship captains and professional ice observers can still
misjudge ice conditions is that, even today, most of them still depend
largely on a disparate mix of manual methods to make sense of
diverse ice information. This is, however, no longer the only option.
In 2011 and 2012, an E&P operator conducted site surveying,
scientific coring, and high-resolution seismic streamer operations
near the coast of Greenland. In this area, the frequent presence
of both large and small icebergs needs to be carefully managed
in order to keep personnel and equipment safe. To assess the
risks from hour to hour, dedicated ice observers tracked bergs
GEOLOGY & GEOPHYSICS
Narwhal set-up on the bridge of the vessel.
around the clock using marine radars and satellite images,
calculated their mass using spreadsheets, and posted their
speed, direction, and position on paper polar plots. Critical
ice information was scattered around the bridge. Obtaining
up-to-date data required ice specialists to print hardcopy
plots and images elsewhere on the ship. Keeping the captain
well informed, especially under extreme conditions, was both
challenging and time-consuming.
The operator’s ice management plan prescribed a threshold
perimeter around the survey vessel, based on the time required to
safely suspend operations and move out of harm’s way. However,
for mobile seismic operations, there was no way to plot the
constantly moving perimeter on paper along with iceberg positions.
Working closely with the captain, ice observers had to estimate
where an encounter might occur and exactly when to move off
site/line. To guarantee the safety of the vessel, crew, equipment,
and environment, they frequently decided to move off location
sooner and wait longer to return than was absolutely necessary.
This resulted in nonproductive downtime.
Prior to the 2013 operating season, the operator learned about
recent advancements in ice data visualization and decided to
optimize and field test Nar whal, a new, integrated ice management
system developed by ION’s Concept Systems. Nar whal
evolved from the company’s 30-plus years of experience in data
management and software development, as well as knowledge
and experience gained during eight seasons acquiring seismic
data in Arctic waters.
Relevant ice information was automatically updated via ION’s
remote data-hosting service and combined, in multiple GIS layers
including marine radar, on a single screen. Geo-referenced map
and satellite data were blended with temporal dimensions in
an animated “calendar” or time-slider. Using existing ice data,
Narwhal predicted iceberg positions over ensuing 24-hour periods
and automatically displayed current iceberg locations, forecasted
trajectories, and the limits of the ship’s safe perimeter on a single
screen, even during mobile operations.
Because the captain and crew could view data in one place,
they could quickly assess risks. It was estimated in 2013 and
2014 that designated ice obser vers gained roughly 30% more
time per shift to make visual obser vations and to discuss options
GEOLOGY & GEOPHYSICS
and risks with the bridge officers. Communications were deemed
more effective and decisions were made faster, and with greater
confidence. With better ice intelligence, the vessel could remain
safely on site longer and could resume operations faster following
an ice incursion into the safety perimeter. This was demonstrated
in September 2014, when ice downtime was reduced by a factor
of three compared to September 2012 at the same location under
similar operational and ice conditions.
Advanced ice data management and visualization technology can
also protect stationary or fixed offshore drilling and production
facilities. For example, many oil fields are located along the infamous
“Iceberg Alley” off the Grand Banks of Newfoundland (where the
Titanic went down.) Every minute the bit stops turning or oil stops
flowing, asset owners lose money. Normally ice management vessels
(IMVs) keep icebergs from penetrating the safety perimeter. At
times, however, IMVs may not be able to defend all the FPSOs and
drilling rigs. During the heaviest ice seasons like 2014, hundreds of
bergs can threaten operations. Recently, a rig had to be towed off
site for a week and another for two weeks until the ice threat passed,
an expensive course of action. Rig day rates and associated costs
offshore Newfoundland are roughly $1 million. Offshore Greenland,
they may be twice as high.
So how can Narwhal’s new ice management technology help? By
integrating more data in one place, automating tasks, and tracking
more icebergs in a timely manner, operators can pinpoint the
arrival and departure of dangerous ice incursions more accurately
than before. Narwhal enables these savings automatically and
does so while also increasing the safety of personnel, equipment,
and the environment.
Another new valuable tool is Narwhal’s “trafficability” or routing
capability. Every vessel has a specific ice class classification,
indicating the maximum concentration of sea ice it can safely
navigate. Combining vessel classes with satellite images and colorcoded ice charts (updated daily) ice analysts can graphically identify
“go” and “no-go” zones. They can quickly determine appropriate
routes for tankers and supply boats to traverse icy waters between
producing fields and the mainland, ensuring safety and minimizing
fuel costs. In the past, even with radar, satellite images and ice charts,
it was very time consuming for ice observers to integrate or update
reams of ice, weather, and ocean information. Using Narwhal’s
fully-integrated ice management tools, every piece of information is
loaded automatically, time-stamped, and geo-referenced in a single
database. As a result, ice observers, captains, and management
can make more informed decisions, reduce downtime and costs
under extreme conditions, and maximize the effectiveness of every
operating season in icy waters. •
Eprinted and posted with permission to ION Geophysical from Offshore
February © 2015 PennWell Corporation
Reprinted with revisions to format, from the February 2015 edition of Offshore
Copyright 2015 by PennWell Corporation