Every year, blue-white glaciers inching down the western slopes of the 100,000-year-old Greenland ice sheet plunge icebergs into Baffin Bay. Slowly melting fragments drift south in the Labrador current along the eastern coast of Canada, heading eventually toward strategic offshore oil facilities on the Grand Banks of Newfoundland. Icebergs and jagged rafts of sea ice threaten the safety of drilling rigs, platforms, oil tankers, and FPSO vessels.

“Iceberg Alley,” as the area is known, has seen more than 500 collisions between icebergs and ships. The HMS Titanic went down a few hundred miles from the Hibernia oil field, site of the world’s largest offshore platform. Hibernia’s gravity-based structure is reportedly designed to withstand a collision with a 1-million-ton iceberg, but no one actually wants to test its durability. Over the past few decades, therefore, operators and service companies working off the coasts of Labrador and Newfoundland have devised clever ice management strategies.

Ice management teams prevent icebergs of all sizes from colliding with rigs and other costly facilities. To locate, track, and predict potential ice hazards in a timely manner, ice specialists require reams of detailed ice, weather, and ocean information. Commercial vendors have developed electronic ice navigation and data management systems. But many of these tools suffer from shortcomings, especially when faced with chaotic, unpredictable ice conditions. ION’s new Narwhal technology represents a step-change in integrated ice data access, visualization, and decision-making efficiency.

As more nations such as Russia open ice-infested waters to exploration and drilling, more operators will need to implement effective ice management operations.

Effective ice management operations

Whenever pack ice or an iceberg threatens an offshore operation, ice management teams can either move the operation or move the ice. Mobile operations such as seismic acquisition find it much easier to dodge the ice. Fixed or relatively fixed facilities such as drilling rigs and FPSO vessels are more complex and costly to move. Every minute the drillbit stops turning or oil stops flowing, asset owners are losing money. This is why every offshore operation in ice-prone waters has a formal ice management plan specifying procedures for almost every conceivable situation. Judgment and sound decisions, of course, are critical pieces of the puzzle.

Ice management vessels (IMVs) are tasked with keeping ice out of the operational area. During a drilling operation off the coast of Greenland, a 1,500-m (4,920-ft) iceberg floated south past a rig. Two days later, a storm shattered the berg into 150 pieces and drove them back north. A handful of IMVs had to pick their way through potentially lethal debris, lassoing fragments with ropes or special nets and towing them away or shoving them off course with their propellers (a technique called prop washing) to ensure the safety of the rig.

Sometimes nature gets out of control, and some part of the operation must be removed from harm’s way. During a heavy ice season off the Grand Banks one year, IMVs defended an FPSO vessel while the semisubmersible rig was towed away for a couple of days until the threat passed. At a cost of perhaps US $1 million per day, operators are loath to take this type of action.

On another occasion, an iceberg had grounded in shallow water 16 km (10 miles) away. In the middle of the night, after sitting harmlessly for days, the berg started to drift toward a tanker offloading oil. To comply with HSE requirements outlined in the ice management plan, the tanker was disconnected and moved away while IMVs deflected the danger. At 5:30 a.m., the partner who owned that particular shipment called to understand exactly what had happened. He had to explain to management why they were paying the overnight carrying charges on 860 MMbbl of oil.

Lost time always impacts the bottom line. Effective ice management, therefore, seeks to mitigate ice risks while reducing downtime to the absolute minimum. An experienced ice observer, rapid access to diverse ice data, and efficient ice management technology are essential to success.

Efficient ice management technology

Anticipating ice threats as early as possible depends on live radar, satellite images, aerial photographs, weather reports, bathymetry, ice and navigation charts, and other information. In the past, ice analysts printed fax reports, plotted hard copy maps and images, and sifted through piles of data scattered about the bridge.

Early ice navigation software combined electronic ice charts, satellite images, and radar on a single computer. However, data files had to be downloaded from various sources via FTP and manually checked for quality. Some data was not geo-referenced or timestamped, making it difficult to visualize, overlay, and correlate one piece with another. Some data such as vessel positioning, weather, currents, and sea temperature could not be accessed. Ice analysis was therefore slow and inefficient.

ION’s own ice observers, working extensive seismic surveys in Arctic waters since 2006, became frustrated with existing software’s inability to automate, integrate, or visualize critical ice data. As a result, ION’s Concept Systems group developed Narwhal for Ice Management, a patented and fully integrated system that automatically downloads, updates, timestamps, and geo-references every ice product available. With unlimited layers, ice specialists correlate, analyze, and visualize all of the ice, weather, radar, and ocean data required to make informed decisions in rapidly changing conditions.

One of the most valuable features is the “trafficability” or routing capability. Every offshore vessel has an ice rating, indicating the concentrations of sea ice it can safely navigate. With vessel ratings and maps of current ice conditions, the software graphically displays – and continually updates – go and no-go zones. This allows ice management teams to determine appropriate routes for tankers and supply boats to traverse icy waters from producing fields to the mainland, ensuring safety and minimizing fuel costs.

The calendar feature in Narwhal can animate ice movements and other changes over any selected period of time. It can run backward or forward in time, even projecting ice trajectories a day or two into the future. At the end of an operational season, ice analysts can visually review ice incursions and towing incidents using the calendar feature to help meet reporting requirements, study ice behaviors, and fine-tune parameters for the next season.

Additional capabilities include multivessel data sharing and visualization, automated alerts for approaching ice, and the ability to track birds and marine mammals in ecologically sensitive areas.

Growing Arctic activity

Declining reserves from mature fields, growing demand for oil, and retreating sea ice have sparked new activities, with six of the eight countries with Arctic territories granting energy companies offshore exploration licenses despite the enormous challenges. To optimize ice defense strategies and ensure the safety of personnel, facilities, and the environment, operators must make timely, well-informed decisions. Reliable ice management technology will be critical to ensuring the industry’s ability to safely explore, develop, and produce in this delicate but harsh environment.

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