SNOW
AND CLIMATE
Click on an outlined
section below to listen to the audio.
(Transcripts will be available soon)

Tape Number: H2001-113-10
Dr. Matthew Sturm
U.S.A. Cold Regions Research & Engineering
Laboratory-Alaska
Ft. Wainwright, AK 99703
2) Begin Slide
Show
water molecule slide\ Blake -- building block\ tetrahedron --
hexagon\ snow molecules\ Hyrdo-meteorites -- building block of
snow|
3) Pictures of snow
crystals and layers of snow
web -- Caltech website\ Snowflake Bentley\ SEM -- department of
agriculture\ hexagons\ layer cake\ SHEBA (Surface Heat Energy Budget
of the Arctic)\ importance of snow to climate|
4) Layers of snow and
types of snow
Dan Solie -- snow in Fairbanks\ layers -- interactions\ perennial
snow\ taiga -- tundra\ glacier\ seasonal snow pack\ perennial snow --
always there\ seasonal snow -- melts every year\
albedo|
5) Metamorphic changes
graph
snow -- close to melting point\ strange properties\ World Trade
Center -- metal close to melting point\ high vapor pressure --
gasoline\ snow -- high vapor pressure\ snow not stable --
metamorphism|
6) Trapped snowflake
experiment
experiment -- 60 years ago\ trapped snowflake -- kept at same temp\
changed -- smooth edges\ snow unstable -- changes\ tetrahedral --
curve\ hydro-meteorite|
7) Snow changes into two
pathways
snow falls on ground -- changes\ equilibrium pathway -- ET round\
temp gradients -- minor\ kinetic growth -- sharp edges\ depth hoar\
Fairbanks\ Nome\ kinetic growth\ temperature gradient -- effects
pathway|
8) Snow crystals
melt grain clusters -- rounded clusters\ wind grains\ kinetic growth\
Steubens glass company -- kinetic growth|
9) Bonds of snow
crystals
snow -- experiment\ snow grains -- connected together\ high vapor
pressure -- sinter\ sinter -- snow bonds\ bonds -- heat moves through
snow|
10) Properties of a snow
pack
layer cake\ properties of snow pack\ thermal conductivity, water
equivalent albedo -- effect climate\ snow -- insulator\ ice crystals
-- air spaces\ heat moves through ice|
11) Thermal
Conductivity
property of snow -- insulator\ thermal conductivity -- snow
insulation\ experiment -- temperature difference|
12) Thermal
conductivity data collection
thermal conductivity of snow\ data collection\ Hjelmstorm -- 1889\
density -- not as good an insulator\ two types of snow in AK\ light
fluffy new snow\ depth hoar -- pukak\ low density -- low thermal
conductivity|
13) Pathway of a layer
cake
snow changes with time\ thermal conductivity changes|
14) Alaska climate
changes
climate\ AK changes -- climate changes\ deeper snow -- warmer\ shrub
density\ snow depth\ soil temperature\ microbial activity\ nutrient
availability|
15) Landscape changes
change landscape\ 1949 -- Chandler River\ 2001 -- same place\
landscape -- changes\ movement of trees north\ tundra change\ thermal
conductiviy|
16) Soil pit
Gary Michaelson and Chen Lui Ping -- soil scientists\ snow --
determines how thick active layer will be\ talik -- layer that
doesn't freeze\ talik -- active ground water all winter\ warming
climate -- snow insulation property|
17) Graph: effects of
warming
everything is linked\ snow trapping -- increased shrubs\ winter
warming -- change permafrost temps\ year round functioning ground
water|
18) albedo and solar
radiation
albedo -- ability to reflect sunlight\ snow -- solar radiation\
reflection\ lakes -- forests\ sunburn|
19) Graph: measuring
albedo throughout a melt season
measuring albedo -- across the melt season\ change in energy
absorbed|
20) Monthly snow cover
charts (Dave Robinson's website:
http://climate.rutgers.edu/snowcover/mainsnow.html)
Dave Robinson -- website\ tracks snow cover -- Northern Hemisphere
through time\ August -- Greenland covered by snow\ white -- high
albedo\ October -- more snow coverage\ March -- even more coverage\
more reflection -- earth cool\ important for climate|
21) Feedback loop
feed-back loops\ thermal conductivity and albedo -- effect climate\
warming climate -- less snow\ more earth dark -- absorbs solar
energy|
22) Sea ice is
shrinking
sea ice -- coastal locations\ Don Perovich -- aerial photo\ sea ice
extent -- shrinking|
23) Water resources
water resources\ fresh water -- comes from snow\ snow runoff -- North
Slope\ water resources will change\ aspect of snow that effects
climate\ break-up|
24) Final thoughts
Matthew's children -- Eli and Skye Sturm\ measuring snow\ temperature probes\ checking the
temp|
25)Q\A
Buckland, Selewick, Ambler -- villages in AK\ volcanic activity --
Pacific Ocean\ volcanoes -- climate changes\ climate trigger\
volcanoes -- lots of gases\ ice ages -- warming and cooling\ earth's
climate system -- change rapidly\ Greenlandic Core -- shifts\ hard to
track patterns\ current atmosphere -- rich in CO2\ warmer temps\ sea
ice -- changes rapidly\ environmental indicators -- tempo uprise\
Eastern Canada -- cooling\ Alaska\ Siberia\ earth -- complex climate
history|
26) Looking at
snow crystals in the classroom
Nikon scope -- stereoscope\ bucket of snow -- in class\ hand lens\
stretch cloth over board\ see flakes\ Tanana -- class\ working in the
cold -- difficult\ old style -- low powered stereo microscopes\
monocular scope -- too powerful\ magnifying glass\ Barrow\ depth hoar
-- between tundra tussocks\ depth hoar -- large crystals\ way to get
crystals\ 6 pointed snowflake\ making a snow flake|
27) Information
on slides
google.com\
Caltech Snowflakes\ Rutgers snow\ resources on the web\ Snowflake
Bentley -- Wilson Bentley http://snowflakebentley.com/snowflakes.htm\
Vermont -- photographed snow flakes\ book of photos\ farm -- now a
museum\ Caltech http://www.its.caltech.edu/~atomic/snowcrystals\
moist layers -- liquid water layer\ rime snow flake\ Nakaya --
snowflake\ messenger from heaven|
28) Snow up and
break up
temperature measurements\ phenology -- changes in timing\ season
changes -- timing\ human judgment\ microbe example\ snow cover --
insulator\ timing of snow and cold -- months\ freeze up-- breakup\
relationship to travel\ things to do in a classroom\ pattern
recognition\ draws pattern on white board\ graphing -- patterns\
elders\ develop models\ 4th graders -- grasp patterns\ something vs.
time\ best fit|
29) How climate
effects people's lives
travel -- later in the season\ hunting\ reindeer herding\
transportation changes -- lack of snow\ challenge students\ something
to think about\ human dimension -- season cycle|
30) Albedo
explaination
albedo works towards cooling\ exchange\ shiny earth -- reflects light
and is cooler\ dark earth absorbs heat\ snow cover -- temps drop\
white and black sweatshirts -- albedo experiments\ high albedo --
reflects energy\ promotes cooling\ temps climbing -- less snow
coverage\ duration of snow\ spring earlier|
31) Climate
Change
Mark Serreze -- expert\ arctic oscillation\ Vikings\ earths climate
changes\ gulf stream\ storms -- cyclones\ Icelandic low\ Azores high\
North Atlantic Oscillation\ Pacific conveyor belt -- united express\
patterns\ centers of warming and cooling\ Eastern Canada -- cold
winters\ Alaska -- warm winters\ Fairbanks warm -- high automobile
accidents\ rain\ latent heat of freezing and cooling\ berries
effected|
Click here to go back to the top of the page