Big Four Glacier
| Mass Balance |
Ice Worms Google earth Distribution map file. |
Snowpack Changes: Snowpack-Precipitation Ratio |
Terminus
Behavior Google Earth Tour of Monitored Glaciers Terminus Data Set |
Glacier Runoff | Updated 5/28/09 |
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David Head (Scrooge) has conducted a photographic examination of
Big Four Glacier in from 2005-2009. At left is a
map by Anderson and Vining in 1970. The question of whether this
is a glacier is an interesting one. Look through this material and
decide for yourself. This is an interesting case. All
photographs besides the map and the 1920 image are from David Head.
Certainly in 2005 there was very little snowpack left, and no evident
glacier ice. Each year from 2006-2008 the Big Four avalanche cone
has added mass. Winter precipitation has been above normal in each
of these three winters. There have also been some notable warm
spells helping release snowpack above in large avalanches. Given
the size of the ice mass in 2008, it now appears to be a glacier.
2009 below proved to be another good year for winter precipitation and one
rain on snow event in January triggered large avalanches in the area.
It will be interesting to see if the large footprint of 2008 can be
maintained. |
Big Four Glacier in 1920. This spot has long been a
visited location. Traffic toward Monte Cristo has been high for a long
time. The amount of debris on the surface of the glacier suggests that
this was summer of severe melting, exposing a number of years worth of
debris. Below is a tunnel at the base of the glacier, indicating
blue multi year ice below the surface layer. The new snow above is
2002, below likely 2000 snowpack.  |
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| Big Four in 2003. The 1999-2002 period featured heavy winter snowpack and avalanching boosting Big Four. The summer of 2003 was the first of three cruel seasons to Big Four. In this image you cannot note the blue case to all but the very top of the avalanche cone, indicating it is older snow. There is further two layers that look to be annual layers on the right side of the image. This suggests to me, the base is a 1999, layer, than a 2000 layer, than a broader dirty band and a 2002 layer, followed by a 2003 snowpack,. The summer of 2001 was warm and no snowpack would have survived, causing the wider dirt band. |
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| Above is Big Four Glacier in the fall of 2005 | Above is Big Four Glacier in the fall of 2006 |
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| Above is Big Four Glacier in the fall of 2007 | Above is Big Four Glacier in the fall of 2008. The top of the snow mass-glacier has now reached to about the greenline in the 2005 photograph. |
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| This sequence of pictures from 2007 indicates Big Four Glacier in July above, August above right, September below and October below right. All photographs from David Head. The October visit required rafting across the Stilliguamish River to reach the glacier. | The change from September to October is modest. The interesting changes is the reappearance of the waterfall from above at the end of the dry season. |
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|
 Big Four in Late June 2008 |
Big Four in September 2008 |