Science Discipline Overview:

Atmosphere (large-scale perspective)

How might large-scale atmospheric challenges

add to the scientific arguments for MOSAIC?

Sources

ISAC (International Study of Arctic Change) Science Plan

SEARCH (Study of Environmental Arctic Change):

Recommendations for Understanding Arctic System Change (Workshop Report)

Others (WCRP Predictability, IASC/Arctic in Rapid Transition,…)

What is the Arctic Ocean’s role as a source/sink of greenhouse gases, aerosol particles, and other chemical species? [ISAC]

Postulated feedback involving DMS[http://me-www.jrc.it/dms/dms.html[

800 m

Methane flares on the Arctic shelves: Is there a summer signature in the central Arctic

[from N. Shakhova and I. Semiletov, IARC]

Arctic seabed methane stores destabilizing, venting Shakhova and Semiletov (2010, Science)

What is the Arctic Ocean’s role as a source/sink of greenhouse gases, aerosol particles, and other chemical species? [ISAC]

Are increases in midlatitudes being augmented or offset by exchanges at the surface of the Arctic Ocean?

Is reduced sea ice cover (area and thickness) altering the Arctic Ocean’s role in the global carbon and sulfur budgets?

Of particular interest: Dimethyl sulfide (DMS) and its role in cloudiness

How much has sea ice loss (area, thickness) contributed to polar amplification of the recent warming? [ISAC]

Change in surface air temperature (°C), 1961-2010[from NASA GISS]

Arctic Antarctic

How much has sea ice loss (area, thickness) contributed to polar amplification of the recent warming? [ISAC]

Sensible heat release from ocean (increased solar absorption)

Changes in atmospheric humidity, cloudiness due to enhanced evaporation

Increased influxes of atmospheric heat and moisture from lower latitudes

Increased inflows of oceanic heat from the North Atlantic and North Pacific

Can a station in the Arctic Ocean provide information relevant to springtime ozone depletion? [ISAC]

Total column ozone measured by satellite[Bernhard et al., 2011, Arctic Report Card]

Can a station in the Arctic Ocean provide information relevant to springtime ozone depletion? [ISAC]

Measurements of potential utility:

Spectral distribution of downwelling radiation

Upper atmosphere profiles

Others?

Can field measurements support a linkage between reduced autumn ice coverage and wintertime atmospheric circulation anomalies affecting middle latitudes?

Latitude-height section of temperature anomalies (135-225ºE)Oct-Dec, 2002-2008

[Overland and Wang, 2010, Tellus]

1000-500 mb thickness anomaliesOct-Dec, 2002-2008

[Overland and Wang, 2010, Tellus]

Can field measurements support a linkage between reduced autumn ice coverage and wintertime atmospheric circulation anomalies affecting middle latitudes?

Enhanced heating of upper ocean in recent summers is substantial (Perovich et al.)

Subsequent release of heat to the atmosphere is not fully understood (i.e., temporal, vertical distributions) – but warming of the lower troposphere is strongly indicated

Mechanisms linking midlatitude weather/climate anomalies to heating of Arctic troposphere need elucidation

How much is the atmosphere contributing to the extreme ice retreat of recent summers? [ISAC]

Satellite-derived cloud fractions, June-August[Stroeve et al., 2011, Climatic Change]

% of sea ice retreat explained by wind (black, blue)downwelling longwave (green),

and sensible hear flux convergence (red)[from Francis et al., 2005]

Arctic Ocean temperatures from NABOS

moorings, 2003-2009

How much is the atmosphere contributing to the extreme ice retreat of recent summers? [ISAC]

Factors to be included in quantitative diagnosis:

Downwelling radiation anomalies (clouds, water vapor)

Wind forcing/ice advection

Atlantic and Pacific water inflows

and

Effects of changes in surface albedo

How do storm events interact with the ice cover and upper ocean?

-- effects of storms on the ice/ocean state-- effects of lower boundary changes on storms

Polar low in Chukchi Sea (2009)

Contours: geopotential height at 500 hPa;

Color: SLP.

The polar low developed after a synoptic scale cyclone intruded into

the Chukchi Sea.

Mirai soundings crucial to diagnosis, initialization of WRF

Moreira et al. 2012

Targeting special observations to enhance weather forecasts –the Norwegian IPY-THORPEX success (Kristjansson et al., 2011)

special obs no special obs

← verifying analysis

LL

L

How do storm events interact with the ice cover and upper ocean?

-- effects of storms on the ice/ocean state-- effects of lower boundary changes on storms

Atmospheric soundings from vicinity of polar low have been found to enhance regional model simulations of system

Surface fluxes should be important to the development of the system

Boundary layer parameterization packages are many – choice of most appropriate modules need observational guidance