Hiroyuki Enomoto National Institute of Polar Research

The Arctic Sea Ice Monitoring and Climate Variation

Monitoring Climate Change from Space COP21 Japan Pavilion, Dec. 4, 2015

Background • Arctic warming rate is twice faster than other regions. • The enhanced change in the Arctic is called “Polar Amplification” of warming.

Sea ice area in September 2012 was nearly half of that in 1980s (JAXA-ADS).

Observed surface air temperature anomalies from the 1880-1890 mean, for each latitude bands, 9 year moving average (Shindell and Faluvegi, 2009).

Noｒｔｈ of ６０N

2012 1980s

“Polar Amplification” and “Feedbacks” in climate system • Arctic sea ice declining became drastic in 2000’s with the

summer minimum record in 2012 (“Early Indicator”). • Arctic sea ice change is an results of warming, and at

same time, sea ice is the cause of accelerating warming by “Ice albedo feedback”.

Summer sea ice

sea

ice

area

Year

atmosphere Insolation

reflection

Snow/ice

Data: JMA

terrestrial radiation

Ｓｅａ ｉｃｅ

Questions arise from Arctic and sea ice Why Arctic warming is so rapid? How sea ice is changing? What is the influence to various fielded of Arctic? How we can monitor, understand, respond to change?

Atmosphere Ocean Terrestrial condition Cryosphere/hydrosphere change and Society

AMSR-2 data products and visualization for Arctic study through ADS/GRENE Arctic Project, NIPR, JAXA

Snow cover Soil moisture

https://ads.nipr.ac.jp/vishop/vishop-monitor.html

Seasonal cycle of sea ice

Large fluctuation

Spring Autumn

Winter temperature is increasing

Summer Sea ice melting is strong air conditioner

Warming is not apparent on this figure, however change is occurring in the other style.

Data:NCEP

Temperature at North Pole

Month-year

Air T

empe

ratu

re (C

)

Summer temperature is very stable and homogeneous on sea ice

Sea ice: reflection of solar radiation

Forming melt pond over sea ice

Heat: ice melt, stored in open water…

Microwave suganal of melt water

Contribution of each processes to Arctic warming amplification

Arctic amplification and feedback Ar

ctic

am

plifi

catio

n in

dex

(AAI

)

CO2 Water vapor Albedo Cloud Surface evap. Large-scale condense. Cumulus Sens. heat + turbulent Advection Ocean heat content

Month

-Warming is small in Jun.-Aug., when solar radiation is reflected by ice. Heat is absorbed in ocean.

-The heat is released in Oct.-Dec.

-Amplified warming is maintained with cloud feedback.

Expanding open water=Ocean: heat storage

Ice : Albedo Heat & vapor release from Ocean+Cloud formation

Summer Autumn

Yoshimori et al. (2014)

Positive Negative

summer

winter spring

autumn

Decay: melting

Opening Lead

River dicharge

Freezing, Growth

Snow cover

Mid-latitude weather,

Ice conditions

Open water, melt pond,

Sea ice seasonal cycle and satellite monitoring

ice thickness

Weather, Transport, Ocean environment

Heat and water vapor, cloud

AMSR-E/AMSR2 thickness : every September 10

Purple-pink: melt pond concentration

2002 2003 2004 2005 2006

2007 2008 2009 2010 2012

2013

Krishfield et al, 2014 Data: Tateyama Kitami Inst. Tech。

Thinning of sea ice

Fragile ice : Thin ice and violent weather

Reduction of sea ice in 2012.8.1-18 Reduction of sea ice in

2012.8.1-18

New Arctic weather condition: Great Arctic Cyclone (GAC)

Wind, wave: Coastal and navigation safety, mixing (ocean), erosion(coast)

summer

winter spring

autumn

Decay: melting

Opening Lead

River dicharge

Freezing, Growth

Snow cover

Mid-latitude weather,

Ice conditions

Open water, melt pond,

Sea ice seasonal cycle and satellite monitoring

ice thickness

Weather, Transport, Ocean environment

Heat and water vapor, cloud

Winter ice growth by dynamic condition, and forecast of summer sea ice Data: GCOM-W AMSR2

Yamaguchi lab. Univ of Tokyo http://www.1.k.u-tokyo.ac.jp/YKWP/2015arctic.html

In situ freezing/sea ice dynamics

Thin / thick ice Dynamic conditions

Winter ice motion for forecasting summer retreat

GRENE Arctic project

Univ. of Tokyo Group N. Kimura and H. Yamahguchi

2013.03.04 & 02.18NOAA Changing winter sea ice conditions Data: GCOM-W AMSR2

Winter sea ice coverage, thickness, movement

Frequent opening/ridging Water vapor and heat releases Summer ice prediction

1979 2014

Cold and snow in the Mid-latitudes

Sea Ice Decrease in winter

Snow and cold air to

mid-latitudes as extreme weather .

Concluding remarks

Satellite observation and advance of analyzing technology provide new understanding of Arctic: Arctic warming Polar Amplification, Ice albedo feed back Ice reduction: more open water, heat + water cycle snow

ocean, cloud, cyclone, atmospheric circulation, snow Application to Society

Weather, Mid-latitude connection, Environment, Coastal safety, Transport and industry

From observation and understanding, Japanese new project ArCS (2015-20) aims to provide scientific information for Arctic environment and sustainable development ,and global role 2015-2020 (MEXT, Japan)

2011-2015 (MEXT, Japan)