Climate change and the cryosphere
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Outline
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Background, climatology & variability
Role of snow in the global climate system
Contemporary observations of climate change
Cryospheric indicators of climate change
Future global & regional projections &
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implications of climate change
Background, climatology & variability
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20th Century Climatology
Observed
Ref: Masuda
GFDL
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Current
snow
coverage
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1 April 2013
Departure
from
average
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1 April 2013
Seasonal
climatology
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Observed & GFDL Northern Hemisphere Snow
Extent (x106 km2), 1973-2000
Season
OBS
GFDL
MAE
RMSE
Winter
44
42
2.4
0.55
Spring
30
35
4.8
1.00
Summer
6
4
2.3
0.51
Fall
19
20
1.7
0.40
Annual
25
25
0.9
0.22
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Mean annual
maximum
monthly snow
water
equivalent
(mm) in
Canada, 19801997
(Brown et al.
2003)
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Current SWE in the Prairies
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Monthly Eurasian standardized snow cover
extent anomalies
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Interannual variability
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Source: Karl et al. (1993).
Role of snow in the global climate
system
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Annual cycle of daily discharge in
Skeena River (1955-2004)
freshet
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Contribution of snow to river runoff
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Source: Barnett et al. (2005).
Teleconnections
Definition: Atmospheric interactions between
widely separated regions that have been identified
through statistical correlations (in space and time).
For example, the El Niño teleconnection with the
Southwest United States involves large-scale
changes in climatic conditions that are linked to
increased winter rainfall.
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Correlation coefficient between annual Eurasian
snow extent anomalies & discharge anomalies
the following year in 64 rivers of northern Canada
Source: Déry et al. (2005), JGR.
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Observed 20th century climate
change
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Warming air temperatures
Climatic Research Unit, University of East Anglia, http://www.cru.uea.ac.uk/
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20th century climate & trends
Reference: Déry and Wood (2005)
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Trends in global surface air temperature
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Trends in global surface precipitation
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Cryospheric indicators of
global change
• Snow depth, swe, density, albedo &
temperature (heat content)
• Duration of snow cover & growing season
• Snowmelt/spring freshet date
• Soil moisture
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Snow depth
Source: Curtis et
al. (1998), Int. J.
Climatology
25
26
Se
p.
1
Oc
t.
1
Oc
t.
31
No
v.
30
De
c.
30
Ja
n.
29
Fe
b.
28
Ma
r.
29
Ap
r.
28
Ma
y.
28
Ju
n.
27
Ju
l.
27
Au
g.
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Average annual cycle of daily
SWE (mm)
Annual cycle of daily snow
accumulation (SWE) at Barkerville
1971-1977
1996-2005
450
400
350
300
250
200
150
100
50
0
Date
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Trend (%)
in April 1st
swe, 19501997
Source: Mote et al.
(2005), BAMS
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Albedo
Source: Stone et al. (2002), JGR.
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Trend
(days/year)
in snow
cover
duration,
1972-2000
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32
Snowmelt
Date
Source: Stone et al. (2002), JGR.
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Reference: Déry and Brown (2007)
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Annual cycle of daily runoff for the
Little Swift River near Barkerville
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Trend in centre of volume in river
discharge across western N. America
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Source: Stewart et al. (2005), J. Climate.
Future projections & implications of
global change
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Components of the climate system
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IPCC 4th Assessment
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IPCC 4th Assessment
Expected
indicators
of climate
change
IPCC 3rd Assessment
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IPCC 4th Assessment
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IPCC 4th Assessment
IPCC 4th Assessment Runs
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Trends in Northern Hemisphere snow cover extent
Source: Déry et al. (2006), JGR.
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Projected change
in seasonal snow
cover frequency
based on GFDL
CM2 simulations
(21st - 20th
century)
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-0
Projected change in frequency
Trends in Northern Hemisphere snow mass
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Projected change
in seasonal snow
water equivalent
(swe) based on
GFDL CM2
simulations
(21st - 20th
century)
-1
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Projected change in swe (mm)
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Regional climate (baseline)
• Source: PCIC (http://www.pcic.uvic.ca)
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Temperature Projections
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Precipitation projections
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Regional
Projections
for snow
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Implications of global change
• Increase in planetary albedo (positive
feedback on global warming)
• Decreasing water resources, including
soil moisture
• Longer growing season
• Impacts on recreational activities
• Ecological implications
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Further reading:
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Points of Discussion:
• Which component of the cryosphere is most
vulnerable to climate change?
• What are the possible environmental impacts
of climate change in Prince George, B.C.,
Canada?
• Will there be any jobs for cryospheric
scientists in the 21st century?
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