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Observed Arctic Ocean clouds, sea ice, and radiative fluxes during the early 21st century. Jennifer E. Kay NCAR/University of Colorado T. L’Ecuyer (Wisconsin) A. Gettelman (NCAR). Image credit: J. Kay/PBI. Arctic vs. Global Warming. Arctic Sea Ice Loss.
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Observed Arctic Ocean clouds, sea ice, and radiative fluxes during the early 21st century Jennifer E. Kay NCAR/University of Colorado T. L’Ecuyer (Wisconsin) A. Gettelman (NCAR) Image credit: J. Kay/PBI
Arctic Sea Ice Loss Data from NSIDCsea ice index September 2012 was 49% of the 1979-2000 average Kay et al. 2011 GRL Figure 1
New data + Ice loss = New discoveries Stephens et al. 2008; Marchand et al. 2008; Winker et al. 2009; Mace et al. 2009; L’Ecuyer and Jiang, 2010
Ubiquitous liquid-containing Arctic Clouds Observed with SpaceborneLidar(2006-2012) Cesana et al. 2012 GRL Figure 1 Retrieval incorporated now in COSP and being used to evaluate climate models.
Outline: Arctic Ocean climatology Implications for cloud feedbacks
Annual Cycle Arctic Ocean Net Radiation Kay, and L’Ecuyer 2013 Figure 1
Annual Cycle Arctic OceanCloud Amount/Radiative Effect Kay, and L’Ecuyer 2013 Figure 3
How do our values compare to SHEBA? Change to figure comparing ice amount in 1996 and 2006-2010
Geographic variations in clouds:Arctic Ocean stability regimes Kay, and L’Ecuyer 2013 Figure 5
Stable vs. Unstable Regime Clouds Kay, and L’Ecuyer 2013 Figure 5
Outline: Arctic Ocean climatology Implications for cloud feedbacks
When were the largest observed Arctic TOA radiation anomalies from 2000-2011? Image credit: National Geographic
Largest monthly anomalies: June 2001, June 2007 and July 2007 The largest observed monthly Arctic Ocean radiation anomalies are associated with cloud anomalies not sea ice anomalies.
Are the clouds responding to Arctic Sea Ice Loss? Image credit: R. Aronson/PBI
Observed cloud response to sea ice loss July 2, 2007 No cloud response to summer Arctic sea ice loss Low cloud increases over newly open water during early fall Kay and Gettelman2009 JGR September 30, 2007 See also Palm et al. 2010 JGR, Wu and Lee 2012 JGR, Kay and L’Ecuyer2013
Kay and L’Ecuyer(JGR, 2013) Longer observational records confirm no summer cloud trend affecting Arctic shortwave radiation Extend to 2012
Summary • Cloud and radiation climatology xxxx. • Cloud anomalies lead to largest radiation anomalies. • Cloud feedbacks are XXX • Observational “golden age”
Kay, J. E. and T. L'Ecuyer (2013): Observational constraints on Arctic Ocean clouds and radiative fluxes during the early 21st century, J. Geophys. Res, 118, doi:10.1002/jgrd.50489. Cesana, G., Kay, J. E., Chepfer, H., English, J.M., and G. de Boer (2012): Ubiquitous low-level liquid-containing Arctic clouds: New observations and climate model constraints from CALIPSO-GOCCP, Geophys. Res. Lett., 39, L20804, doi:10.1029/2012GL053385. Kay, J. E., Holland, M. M., and A. Jahn (2011): Inter-annual to multi-decadal Arctic sea ice extent trends in a warming world, Geophys. Res. Lett., 38, L15708, doi:10.1029/2011GL048008 Kay, J. E. and A. Gettelman (2009): Cloud influence on and response to seasonal Arctic sea ice loss, J. Geophys. Res., doi:10.1029/2009JD011773.
Climate models can qualitatively reproduce observed Arctic sea ice loss… but have large internal variability. Kay, Holland, Jahn 2011 GRL