The U.S. Geological Survey study says the smaller, more frequent icebergs could become a threat to bridges and communities and may also damage equipment and underwater cables.
The study estimates that the number of icebergs in Glacier Bay, which opens up to the Gulf of Alaska, could jump by 40 percent by 2100.
While the size of the icebergs likely will decrease — because they will have broken off earlier — there will be more of them, according to the report.
“In the future, the icebergs will all be smaller, but there will be twice as many of them,” said Erin Pettit, the study’s lead author.
The number of icebergs in Icy Bay is projected to increase by about 20% by the end of the century.
The projected increase is due to rising ocean temperatures, which cause glaciers to retreat. When a glacier retreats, it becomes thinner, and the ice becomes more fractured.
This makes it more likely that the glacier will calve off icebergs.
The increase in icebergs in Glacier Bay and Icy Bay could have a significant impact on ship traffic in the region.
The Port of Juneau is located at the mouth of Gastineau Channel, which is about 10 miles from Glacier Bay.
The port is a major hub for cruise ships and commercial fishing vessels.
The increase in icebergs could also pose a threat to oil tankers traveling to and from the Valdez terminal.
The Valdez terminal is located about 150 miles from Glacier Bay.
The risk of accidents, oil spills, and other environmental disasters may increase as more icebergs enter these shipping routes and waterways, the scientists say.
“A lot of the ships that transit that area and go to Valdez are going to be exposed to higher iceberg frequency and more hazards. It's something we need to start looking into now, so we can start planning and addressing the potential impacts,” Pettit said.
According to the study, the size of icebergs in the Glacier Bay area will likely decrease from an average of 4 to 6 kilometers in length to an average of 1 to 2 kilometers in length.
This is because a warming climate is causing glaciers to melt at an accelerated rate.
The researchers also found that some of the glaciers that currently produce icebergs may cease to do so by 2100.
However, other glaciers may start to produce icebergs by the end of the century, as they retreat and become thinner.
The potential increase in smaller icebergs in Alaska’s waterways would have implications beyond the shipping industry, the study said.
The changes could affect tourism and fishing, and could cause damage to infrastructure such as bridges, fish hatcheries and underwater pipelines.
“You can’t just put up a stop sign for an iceberg,” Pettit said.
The researchers said the increase in smaller, more frequent icebergs is a complex challenge that will require a collaborative effort from scientists, government agencies, and industry to mitigate the potential risks and impacts.
