Glaciers Of The North Cascades

The  North  Cascades  are  home  to  the  most  glacial  masses  in  the  lower  forty   eight  states.  This  part  of  the  world  is  Gods  country;  the  sheer  beauty  of  the   landscape  is  breathtaking.  Most  of  the  beauty  of  this  land  has  been  touched   by  ice.  The  North  Cascades  sit  in   the  northern  most  part  of   Washington  State.  This  region  is   filled  with  countless  canyons   and  cirques,  cliffs  and  knobs.   Within  the  Cascades  lie  five   active  volcanoes  that  tower  over  12,000  feet  above  the  valley  floor.  The   tallest  non-­‐volcanic  peak  is  over  9,000  feet.  This  massive  area  is  prime  for   the  building  of  ice  and  snow,  key  ingredients  in  glacial  formation.   Washington  State  is  an  excellent  place  to  find  glaciers  as  the  relatively  warm   climate  and  abundant  snowfall  exceeds  the  loss  of  snow  due  to  summer  melt.     Some  the  mountains  in  Washington  that  you  will  find  glaciers  are  Mount   Rainier,  Mount  Baker,  Glacier  Peak,  and  Mount  Olympus.       At  the  high  end  of  where  more  snow  accumulates  than  is  lost  is  called  the   accumulation  zone  this  where  glaciers  are  composed  of  fallen  snow  that  is   compressed  after  many  years  in  thick  ice  masses  and  form  when  snow  stays   in  one  location  long  enough  to  be  transformed  into  ice.  Glaciers  will  form   where  the  yearly  snowfall  is  more  than  the  loss  of  snow.    Every  year  new   layers  of  snow  cover  the  previous  years  falls;  the  compression  forces  snow  to   recrystallize,  forming  grains  the  size  of  sugar.  Slowly  the  grains  grow  larger   3  

and  the  air  pockets  between  the  grains  gets  smaller  causing  the  snow  to   increase  in  density.  After  about  two  winters  the  ice  turns  into  firn.  As  the   glacier  increases  in  weight  it  causes  glacial  movement.  A  glacier  is  unique   because  of  their  ability  to  move.   The  lower  region  where  the  more  snow  is  lost  than  is  gained  through   snowfall  and  the  ice  flows  downhill  into  the  lower  region  is  called  the   ablation  zone,  and  in  the  summer  there  usually  isn’t  any  snow,  leaving  the  ice   exposed.   Between  the  two  zones  is  a  transition  called  the  equilibrium  line,  where   the  annual  accumulation  equals  ablation.  This  line  is  visible  in  the  summer  as   the  transition  between  the  snow  covered  portion  of  the  glacier  and  the  lower   ice  section.   There  are  eleven  classified   types  of  glaciers  in  the  word.   There  are  only  four  found  in   the  Cascades.  The  most   common  found  here  are,  the   mountain  glaciers.  They  often   form  at  high  elevations  where   the  temperature  consistently  touches  below  zero.  These  make  up  the  bulk  of   the  ice  fields  found  here.  The  Valley  glaciers  are  often  spurred  off  of  valley  

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glaciers,  they  often  look  like  a  giant  tongue,  and  they  can  be  very  long  flowing   down  beyond  the  snow  line  and  sometimes  down  to  sea  level.     Glaciers  affect  the  landscape  by  the  way  they  transport  material  and  the   way  they  carve  land  from  beneath  them,  they  will  move  broken  rocks  and   soil  and  leaves  behind  a  landscape  that  has  been  completely  changed.    The   evidence  that  these  massive  ice  flows  have  passed  through  this  land  is  found   all  around.  Another  type  of  glacier  that  can  be  found  in  the  North  Cascades  is   the  Cirque  Glaciers,  which  is  named  for  the  bowl  like  hollows  they  occupy,   called  cirques.  They  are  usually  found  high  on  mountainsides  and  tend  to  be   wide  rather  than  long.    Cirques  are  created  when  glaciers  erode  backwards   into  mountainsides,  creating  rounded  out  hollows  shaped  like  a  shallow  

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bowl.      Nooksack  Cirque,  the  headwaters  of  the  North  Fork  of  the  Nooksack   River,  is  a  valley  that  has  been  scared  by  valley  glaciers.  The  canyon  walls   have  been  rubbed  smooth.  This  is  the  land  of  rocks;  rocks  left  over  from  an   age  when  glaciers  covered  the  area  like  a  blanket.  As  the  vast  sheets  of  ice   slowly  move  down  the  canyon  they  scrape  the  walls  of  the  canyon  down  to   the  bedrock.  This  rock  is  ground  down  to  these  smooth  sheets  found  on  the   walls  of  Nooksack  Cirque.   Today  the  only  glacier  left  in  Nooksack  Cirque  lives  up  to  its  name.  A   Cirque  glacier  hangs  at   the  end  of  the  valley.   These  rugged  glaciers   form  low  on  a  canyon   avoiding  the  sunlight   for  most  of  the  day.   Most  of  the  glaciers   move  rapidly  down  the  side  of  the  canyon  wall.  Some  of  these  glaciers  are   completely  covered  with  rock.  It  is  possible  to  be  standing  on  a  glacier  of  this   type  with  out  knowing  it.  The  lower  portion  of  these  glaciers  is  in  sheet  form.   Vast  flat  expanses  of  ice  formed  as  the  wash  from  the  glacier  refreezes  on  top   of  itself.  Hanging  glaciers  are  very  similar  to  the  cirque  glacier.  These   however  are  found  much  higher  in  elevation.  The  slopes  of  Jack  Mt.  and  Ruby   Mt.  are  home  to  four  of  these  types  of  ice  masses.  The  flat  surfaces  of  ice  often  

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produce  avalanches.  As  the  winter  snow  accumulates  and  freezes  to  the   surface  ice  of  the  glacier.  The  top  layer  remains  soft  and  unstable.     Crevasses  are   found  on  the  glaciers   on  the  Lower  48   peaks  like  Mt.  Rainer,   Mt.  Hood,  Mt.   Olympus  and  Mt.   Adams.  Crevasses   often  appear  where  a   glacier  scrapes   against  uneven  valley  walls  or  turns  a  corner.    A  crevasse  is  one  of  the   treacherous  things  you  will  find  on  a  glacier.     Which  way  are  the  glaciers  in  the  Cascades  heading?  Are  they  shrinking,   staying  the  same  or  growing?  Spider  Glaciers  in  the  North  Cascades  has   shown  what  glaciers  in  most  parts  of  Washington  are  doing.    A  recent  hike   into  the  area  by  Andrea  Imler  it  was  noted  that  what  once  was  a  glacier  is   now  a  snowfield  and  in  a  few  years  it  will  be  extinct.  Another  glacier  in  the   same  area,  Lyman  Glacier  is  estimated  to  have  shrunk  about  one  third  of  its   former  size  and  in  the  past  50  years  has  receded  about  33  feet  per  year  and   in  30  to  50  years  is  predicted  that  it  will  completely  disappear.  The  same  is   true  for  Nooksack  Cirque.    National  Park  Service  ices  are  tracking  glacier  

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melting  rates  in  the  North  Cascades  National  Parks  by  Jon  Riedel  who  is  a   geologist,  says  the  “ice  is  melting  fast  especially  in  the  last  16  years.    What  the   loss  of  glaciers  means  is  that  there  will  be  less  in  the  “glacial  bank  account”   and  the  loss  of  about  400  billion  gallons  of  water,  that  represents   approximately  one  month  of  flow  of  the  Skagit  River,  less  snowpack  means   less  water  for  fish  and  wildlife,  hydropower,  forest  fire  control  and   agriculture.  Riedel  feels  this  is  because  it  is  getting  warmer  and  thinks  it’s   related  to  humans  and  their   impact  on  the  atmosphere.     More  a  research  scientist  at   University  of  Washington   says,  everything  is  now   retreating,  and  the  smaller   glaciers  are  disappearing.”  It   is  being  said  that  the  amount   of  snow  falling  in  the   Northwest  is  becoming  less  while  the  temperatures  are  rising.    “The  decline   in  snowfall  in  the  Northwest  has  been  the  largest  in  the  West,  and  it  is  clearly   related  to  t  (Sohn)emperature,  “  Mote  said.   Glaciers  in  the  Northwest  tell  their  own  stories  of  time  and  come  in   different  sizes,  shapes  and  color,  but  the  one  thing  that  all  glaciers  have  in   common  is  that  they’re  just  one  of  the  unique  pieces  of  creation  revealing   God  himself  as  Romans  1:20  says,  “For  since  the  creation  of  the  world  God’s   8  

invisible  qualities  -­‐-­‐  his  eternal  power  and  divine  nature—have  been  clearly   seen,  being  understood  from  what  has  been  made,  so  that  men  are  without   excuse.”  

     

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