Forecasting changing sea ice conditions months to years in advance
Julienne Stroeve Senior Scientist National Snow and Ice Data Center September 30, 2015
State of the Arctic
UCAR Congressional Briefing – September 2015
State of the Arctic
Accelera'ng ice loss
Modern Satellite Era Various ship, aircraft, early satellite, in situ data, whaling ship log reports
Average summer ice loss from 1850-‐2015 = -‐19,357 km2 yr-‐1
Average summer ice loss from 1979 to 2015: -‐83,090 km2 yr-‐1
UCAR Congressional Briefing – September 2015
State of the Arctic
Shipping routes are opening
August 22, 2007
Northern Sea Route NSR open since 2008
NWP open most years since 2007
UCAR Congressional Briefing – September 2015
State of the Arctic
Probability that the Northern Sea Route will be ice free
80% Ice-‐Free 50% Ice-‐Free
Russia
Murmansk
Using the NSR, ships can reduce the distance between Europe and Asia by 40%
Increasing need for shorter-‐term predic'ons
Median PredicCon Spread in PredicCons Observed Ice CondiCons
UCAR Congressional Briefing – September 2015
State of the Arctic
Need for predic'ng spa'al distribu'on of ice condi'ons
NCAR NASA NOAA University of Washington
NSIDC
Probability of Ice (0-‐100%)
0 20 40 60 80 100%
Observed ice edge in 2014
UCAR Congressional Briefing – September 2015
State of the Arctic
How to improve seasonal forecasts?
• We also need a beVer understanding of important processes such as melt ponds and ocean upwelling.
• Having the necessary observa'ons to ini'alize the forecasts. For example maps of ice thickness are cri'cally needed.
UCAR Congressional Briefing – September 2015
State of the Arctic
• A dedicated polar predic'on effort is needed.
• The proposed Year of Polar Predic'on (YOPP) from mid-‐2017 to mid-‐2019 will bring together the interna'onal community in a period of intensive observing, modeling, predic'on, verifica'on, user-‐engagement. • This is an opportunity for the US to contribute to improved polar predic'on.
• Polar predic'on systems lag weather predic'on by several decades.