Refining projections of the 'warm Arctic, cold Siberia' pattern in climate model simulations
1. Refining projections of the
'warm Arctic, cold Siberia'
pattern in climate model
simulations
Zachary Labe
Colorado State University
With
Yannick Peings & Gudrun Magnusdottir
10 September 2020
Yale University
Atmosphere and Ocean
Climate Dynamics
Seminar
20. [Newson, 1973;
Nature]
“…great warming of the
lower layers of the
troposphere over the
Arctic basin... In fact,
there is a lowering of
mid-latitude continental
temperatures near the
surface”
21. Global climate change
Northern Hemisphere
mid-latitude weather
Arctic
Amplification
Changes in:
+ Storm tracks
+ Jet stream
+ Planetary waves
Natural Variability
+ Internal modes
+ Solar cycle
+ Volcanoes
Northern Hemisphere cryosphere changes
+ Summer and early fall Arctic sea-ice loss
+ Fall Eurasian snow cover increases
+ Late fall and winter Arctic sea-ice loss
Polar Vortex
[adapted/changed from
Cohen et al., 2014;
Nature Geosciences]
22. Global climate change
Northern Hemisphere
mid-latitude weather
Arctic
Amplification
Changes in:
+ Storm tracks
+ Jet stream
+ Planetary waves
Natural Variability
+ Internal modes
+ Solar cycle
+ Volcanoes
Northern Hemisphere cryosphere changes
+ Summer and early fall Arctic sea-ice loss
+ Fall Eurasian snow cover increases
+ Late fall and winter Arctic sea-ice loss
Polar Vortex
[adapted/changed from
Cohen et al., 2014;
Nature Geosciences]
23. Global climate change
Northern Hemisphere
mid-latitude weather
Arctic
Amplification
Changes in:
+ Storm tracks
+ Jet stream
+ Planetary waves
Natural Variability
+ Internal modes
+ Solar cycle
+ Volcanoes
Northern Hemisphere cryosphere changes
+ Summer and early fall Arctic sea-ice loss
+ Fall Eurasian snow cover increases
+ Late fall and winter Arctic sea-ice loss
Polar Vortex
[adapted/changed from
Cohen et al., 2014;
Nature Geosciences]
24. Global climate change
Northern Hemisphere
mid-latitude weather
Arctic
Amplification
Changes in:
+ Storm tracks
+ Jet stream
+ Planetary waves
Natural Variability
+ Internal modes
+ Solar cycle
+ Volcanoes
Northern Hemisphere cryosphere changes
+ Summer and early fall Arctic sea-ice loss
+ Fall Eurasian snow cover increases
+ Late fall and winter Arctic sea-ice loss
Polar Vortex
[adapted/changed from
Cohen et al., 2014;
Nature Geosciences]
25. Global climate change
Northern Hemisphere
mid-latitude weather
Arctic
Amplification
Changes in:
+ Storm tracks
+ Jet stream
+ Planetary waves
Natural Variability
+ Internal modes
+ Solar cycle
+ Volcanoes
Northern Hemisphere cryosphere changes
+ Summer and early fall Arctic sea-ice loss
+ Fall Eurasian snow cover increases
+ Late fall and winter Arctic sea-ice loss
Polar Vortex
[adapted/changed from
Cohen et al., 2014;
Nature Geosciences]
26. Global climate change
Northern Hemisphere
mid-latitude weather
Arctic
Amplification
Changes in:
+ Storm tracks
+ Jet stream
+ Planetary waves
Natural Variability
+ Internal modes
+ Solar cycle
+ Volcanoes
Northern Hemisphere cryosphere changes
+ Summer and early fall Arctic sea-ice loss
+ Fall Eurasian snow cover increases
+ Late fall and winter Arctic sea-ice loss
[adapted/changed from
Cohen et al., 2014;
Nature Geosciences]
Polar Vortex
31. [ SIT ]
Sea Ice
Thickness
Depth between sea
surface and ice/snow
layer
[ SIC ]
Sea Ice
Concentration
Fraction (%) of seawater
covered by ice
Snow
Ice
[ SIE ]
Sea Ice
Extent
Area of seawater
covered by any
amount of ice (>15%)
32. [ SIT ]
Sea Ice
Thickness
Depth between sea
surface and ice/snow
layer
[ SIC ]
Sea Ice
Concentration
Fraction (%) of seawater
covered by ice
Snow
Ice
[ SIE ]
Sea Ice
Extent
Area of seawater
covered by any
amount of ice (>15%)
33. [ SIT ]
Sea Ice
Thickness
Depth between sea
surface and ice/snow
layer
[ SIC ]
Sea Ice
Concentration
Fraction (%) of seawater
covered by ice
Snow
Ice
[ SIE ]
Sea Ice
Extent
Area of seawater
covered by any
amount of ice (>15%)
35. R/V Lance – Greenland Sea – May 2017
Turbulent heat fluxes
[ SIC ]
36. R/V Lance – Greenland Sea – May 2017
Turbulent heat fluxes
[ SIC + SIT ]
37. WACCM4
Whole Atmosphere
Community Climate
Model version 4 –
Specified Chemistry
“high top”
chemistry-climate
atmosphere
model
Physical
parameterizations
from CAM4
• 66 vertical levels – extending to
5 x 10-6 hPa (140 km)
• 1.9° latitude x 2.5° longitude
• QBO prescribed from
radiosonde observations
• Improved representation of
sudden stratospheric warming
(SSW) events
• fixed radiative forcings from
year 2000
38. !SIT = FIT – HIT
!SIC = FIC – HIC
!NET = FICT – HIT• Loss of sea-ice
thickness and
concentration
• Loss of sea-ice
thickness
• Loss of sea-ice
concentration
41. Future Arctic
How does sea-ice thickness
decline influence the large-
scale atmospheric response?
Significant thermodynamic
response over Arctic Ocean
Poleward weakening of jet
LABE ET AL. 2018, GRL
42. Future Arctic
Significant thermodynamic
response over Arctic Ocean
Poleward weakening of jet
LABE ET AL. 2018, GRL
How does sea-ice thickness
decline influence the large-
scale atmospheric response?
48. Assess the role of the Quasi-biennial
Oscillation (QBO) on the atmospheric
response to Arctic sea-ice loss
Composite response by
QBO phase (~67 years)
Modulation
by QBO
Sea ice
experiments
50. Assess the role of the Quasi-biennial
Oscillation (QBO) on the atmospheric
response to Arctic sea-ice loss
Composite response by
QBO phase (~67 years)
Modulation
by QBO
Sea ice
experiments
Future (2051-2080)
Historical (1975-2005)
51. Assess the role of the Quasi-biennial
Oscillation (QBO) on the atmospheric
response to Arctic sea-ice loss
Composite response by
QBO phase (~67 years)
Modulation
by QBO
Sea ice
experiments
Future (2051-2080)
Historical (1975-2005)
52. Assess the role of the Quasi-biennial
Oscillation (QBO) on the atmospheric
response to Arctic sea-ice loss
Modulation
by QBO
Sea ice
experiments
Composite response by
QBO phase (~67 years)
Easterly (QBO-E)
Westerly (QBO-W)
53. Assess the role of the Quasi-biennial
Oscillation (QBO) on the atmospheric
response to Arctic sea-ice loss
Modulation
by QBO
Sea ice
experiments
Composite response by
QBO phase (~67 years)
Easterly (QBO-E)
Westerly (QBO-W)
54. Assess the role of the Quasi-biennial
Oscillation (QBO) on the atmospheric
response to Arctic sea-ice loss
Sea ice
experiments
Composite response by
QBO phase (~67 years)
Modulation
by QBO
Surface (thermodynamic)
Troposphere/Stratosphere
62. MOTIVATION
ARCTIC SEA ICE
MID-LATITUDE
WEATHER
Sea-ice thickness variability is important for reinforcing the
atmospheric response
Strength of Siberian High closely related to Eurasia cold spells
QBO can modulate teleconnections due to Arctic sea-ice loss
63. MOTIVATION
ARCTIC SEA ICE
MID-LATITUDE
WEATHER
Sea-ice thickness variability is important for reinforcing the
atmospheric response
Strength of Siberian High closely related to Eurasia cold spells
QBO can modulate teleconnections due to Arctic sea-ice loss
64. MOTIVATION
ARCTIC SEA ICE
MID-LATITUDE
WEATHER
Sea-ice thickness variability is important for reinforcing the
atmospheric response
Strength of Siberian High closely related to Eurasia cold spells
QBO can modulate teleconnections due to Arctic sea-ice loss
109. Dependence of the
Siberian High response on
polar mid-tropospheric
warming
Gray bar shows the
uncertainty range between
NCEP/NCAR R1 and ERA5
for 10-year epochs
110. 1. Climate models forced only by sea-ice anomalies do not
capture the vertical extent of Arctic warming
2. Increase in 1000-500 hPa layer is linked to a strengthening of
the Siberian High and cold anomalies in eastern Asia
3. Role of the stratosphere is unclear due to large internal
variability at future global warming levels of 2°C
Arctic amplification >> sea-ice loss
111. 1. Climate models forced only by sea-ice anomalies do not
capture the vertical extent of Arctic warming
2. Increase in 1000-500 hPa layer is linked to a strengthening of
the Siberian High and cold anomalies in eastern Asia
3. Role of the stratosphere is unclear due to large internal
variability at future global warming levels of 2°C
Arctic amplification >> sea-ice loss