How hurricanes and tropical storms impact Alaskans

ANCHORAGE (KTUU) -


(App users, to view the interactive data visualization, follow this link).

Methodology:
Data is sourced from Weather Underground's Hurricane Archive.

Use this interactive data visualization above to:
- Examine how many tracked storms occurred globally between 1851 through 2015.
- Examine how many deaths were tracked globally as a result of these annual storms.
- Examine which storm names were retired between 1950 and 2015.

It's important to note that there is no absolute correlation between deaths and storm severity. Aside from storm severity, many other factors play into the causes of death, including population density and city infrastructure, to name a few.

For instance, Alaska climatologist Brian Brettschneider says when Haiti is struck with a hurricane, many deaths result from mudslides, which are triggered from excessive deforestation of the area. He adds that this does not necessarily happen in the Dominican Republic, Haiti's neighboring country.

Additionally, storm names are retired when deemed significant enough by the World Meteorological Organization's Hurricane Committee, which was created on March 23, 1950.

"When a storm has caused a significant loss of life or property damage, out of respect for the people affected by that storm, they (WMO) will retire the name," said Brettschneider. "There is no set criteria, but each year in the Atlantic, they send probably two – on average – names into retirement."

As of 2015, zero storm names have been retired in the Indian Ocean. According to Brettschneider, naming storms in that region has only begun "fairly recently," and that the area only began getting "really good data" starting around 1971.

Story:
It's a fact that Alaskans don't experience hurricanes in the 49th state; however, that does not mean the storms have zero impact on the Last Frontier.

According to Brian Brettschneider, a specialist in hurricane climatology with UAF’s International Arctic Research Center, Alaska is impacted by recurving extra-tropical storms – otherwise known as typhoon remnants.

Brettschneider says that extra-tropical storms occasionally occur when a typhoon – a Pacific hurricane – leaves an area of "really warm, tropical waters." Furthermore, Alaska is affected when a typhoon brushes past Japan or the Philippines and heads northward towards the state.

"At least once or twice every year, the remains of a typhoon will enter the Aleutians or even the Bering Sea," says Brettschneider. "And sometimes, it can quite dramatically have lots of wind and even storm surge impacts that affect the West Coast and even the Aleutian Islands. So it’s not a typhoon anymore, but we would call it remnants of a typhoon from the Western Pacific."

One recent example of this occurred in 2014, following Typhoon Nuri.

That year, when Typhoon Nuri brushed past Japan and continued into the North Pacific, "it transformed into a very, very strong extra-tropical low pressure system that caused winds gusting to near 100 mph," says Brettschneider. As a result, he says the large storm surge impacted the west coast of Alaska, all the way up to Nome. And as the storm progressed into the Gulf of Alaska, Southcentral Alaska ended up getting a lot of rain and wind, especially near Anchorage.

He adds that these storms would mostly likely fall upon Alaska between the months of late summer to fall.

While a storm's movement is difficult to forecast, its "long history," prior to transforming into an extra-tropical storm, makes it rather convenient for Alaska climatologists, says Brettschneider.

"The National Weather Service usually has a good idea at predicting what the impacts will be and advises people appropriately - given potential storm surges and wind impacts," he says.

Aside from a hurricane's distant impact on Alaska, Brettschneider says that the state also has an impact on forming hurricanes.

"Occasionally, a disturbance that’s associated with the jet stream that’s moving past Alaska – maybe a storm in the Gulf of Alaska – will continue on to the east," he says. "And as it approaches maybe the lower part of the 48, it tends to break down the tropical ridge, which causes an existing storm to bend and travel a lot farther to the north."

Brettschneider says that a notable example of this was Hurricane Sandy in 2012. He adds that even Hurricane Irma had potential to have been affected by Alaska.

"The disturbance that is going to pull Hurricane Irma to the north was actually not too far away from Alaska, two or three days ago," he states. "So it’s a little bit of a global circulation nexus that can trace back to thousands of miles from the hurricane’s location."

As far as storm preparation goes, Brettschneider recommends that the public heeds the advice of the local emergency management officials. This goes for populations near hurricane and extra-tropical storm scenarios alike.

"It's always a good idea – no matter where you live – to have emergency provisions," he says. "I think here in Alaska, we're probably doing better than most. Because so many people are out hunting, camping, fishing and are use to living off the grid or semi-off the grid... we're probably better prepared than most places. It is always a good idea to think ahead and have a plan ready to implement, should the case arise."