Alaska gets a ton of snow. Possibly the most snow on Earth. But why?

It’s an important question especially since Alaska is not only one of the snowiest places on Earth, but also holds some of its best terrain for skiing and snowboarding, specifically in the Chugach Range of southern Alaska. The pros flock there every March and April to prove themselves and deliver stunning footage of the best skiing and riding found anywhere in the world.

The Science

Why does Alaska most likely get more snow than anywhere else on Earth? (We only say “most likely” as there just aren’t many measurements in Alaska. No one is out in the middle of the Chugach or on the Bagley Icefild or on the Juneau Icefield taking measurements to confirm the insane amount of snow that falls there.)

The answer is an interesting combination that keeps the Alaskan snow machine firing:  

Polar Jet Stream + Aleutian Low + Positive PDO  

=

Big Snow in Alaska

PDO is a pattern of ocean-atmosphere climate variability that, when positive, shows an increase in rain and snow in Alaska. When it is positive, AK is 3x more likely to see low pressure storms.

In it’s most basic form, this system is pretty simple:  

A semi-permanent low pressure center called the Aleutian Low gathers storms, the Polar Jet Stream consistently blows those storms into mainland Alaska, and a Positive PDO leads to more storms showing up in the Aleutian Low in Alaska. The Polar Jet Stream and the Aleutian Low define the storm track for the Alaska region.

Ok, now lets definite these three important terms:

Aleutian Low

The Aleutian Low is a semi-permanent low pressure center located near the Aleutian Islands of AK during the winter. It is one of the main centers of action in the atmospheric circulation of the Northern Hemisphere. Low pressure = storms.

***

Polar Jet Stream

The Polar Jet Stream is belt of powerful upper-level winds that sits at mid-latitudes in Alaska.  The polar jet streams blow faster than the subtropical jet stream we are used to in the Lower 48. Most large winter storm systems form and move along the polar jet stream, so the position and strength of the stream dramatically influence Alaskan storm patterns.

***

Pacific Decadal Oscillation (PDO)

Pacific Decadal Oscillation is a robust, recurring pattern of ocean-atmosphere climate variability centered over the mid-latitude Pacific basin. The PDO is detected as warm or cool surface waters in the Pacific Ocean, north of 20° N latitude.  This climate pattern affects coastal sea and continental surface air temperatures from Alaska to California.

“Bond and Harrison (a study published in the year 2000) found that during the positive phase of the PDO, low pressure storms (also called upper-level troughs) were 3 times more likely along the 170^o W meridian than ridges (high pressure)” – NOAA

** Check out the constantly spinning air in Southern Alaska where the best skiing is: the Chugach Mountains. This video (above) shows exactly how the polar jet stream works. NASA/Goddard Space Flight Center

What does this mean for skiers and snowboarders?

This means that Alaska is situated in the perfect place to take advantage of the Aleutian Low, the Polar Jet, and a Postive PDO and receive storm after storm all winter long.

Thompson Pass is the snowiest documented place in Alaska, recording an average of 551.5″ of snow per year.  The pass also holds the Alaskan record for the most snow in a single day: 62 inches fell on December 29, 1955.

The city of Valdez, near the legendary heli skiing terrain of Thompson Pass, averages 85 snow days per year and 326″ of snowfall—and it’s at sea level…

Alyeska Ski Resort, 40 miles outside of Anchorage, is the snowiest ski resort in North America averaging 650″ of snowfall per year.  

Alyeska lies 27 miles outside of Anchorage, and consistently gets some of the most snow out of any ski resort in the U.S. and Canada. 

Alyeska Ski Resort is certainly no stranger to powder. In the 2011-2012 season, Alyeska got a whopping 978″ of snowfall.

Seriously: check out these ridiculous annual snowfall totals:

2014-2015	478″
2013-2014	476″
2012 – 2013	726″
2011 – 2012	978″
2010 – 2011	515″
2009 – 2010	880″
2008 – 2009	616″
2007 – 2008	875″
2006 – 2007	668″
2005 – 2006	710″
2004 – 2005	657″
2003 – 2004	763″
2002 – 2003	557″
2001 – 2002	606″
2000 – 2001	939″
1999 – 2000	818″

 

 

 

 

 

 

 

 

 

 

 

 

 

Need more proof?

Alyeska’s Weekly Conditions Report

Easily the largest state in the U.S., Alaska is 663,298 square miles, could comfortably fit the next three largest states inside its borders (California, Texas, and Montana), and most likely gets more snow than any other state. Alaska not only has the country’s highest point (Denali at 20,320 feet), but also the coldest temperature on record (-80 F in Prospect Creek, 1971) and technically speaking, it’s the furthest north, west, and east (think international dateline) state in the USA.

For powder seekers—there’s no other place on Earth like AK.