ACPD Atmospheric Chemistry and Physics Discussions ACPD 1680-7375 Copernicus GmbH Göttingen, Germany 10.5194/acpd-11-31495-2011 Arctic clouds and surface radiation – a critical comparison of satellite retrievals and the ERA-interim reanalysis Zygmuntowska M. 1 2 Mauritsen T. 1 Quaas J. 1 3 Kaleschke L. 4 Max Planck Institute for Meteorology, Hamburg, Germany Nansen Environmental and Remote Sensing Center, Bergen, Norway Leipzig Institute for Meteorology, University of Leipzig, Germany Institute of Oceanography, University of Hamburg, Germany 01 12 2011 11 11 31495 31522 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys-discuss.net/11/31495/2011/acpd-11-31495-2011.html The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/11/31495/2011/acpd-11-31495-2011.pdf

Clouds regulate Earth's radiation budget, both by reflecting part of the incoming sunlight leading to cooling and by absorbing and emitting infrared radiation which tends to have a warming effect. Globally averaged, at the top of the atmosphere the cloud radiative effect is to cool the climate, while at the Arctic surface, clouds are thought to be warming. Ground-based observations of central Arctic Ocean cloudiness are limited to sporadic field campaigns. Therefore many studies rely on satellite- or reanalysis data. Here we compare a passive instrument, the AVHRR-based retrieval from CM-SAF, with recently launched active instruments onboard CloudSat and CALIPSO and the widely used ERA-Interim reanalysis. We find that the three data sets differ significantly. In summer, the two satellite products agree having monthly means of 70–80 percent, but the reanalysis are approximately ten percent higher. In winter passive satellite instruments have serious difficulties, detecting only half the cloudiness of the reanalysis, active instruments being in between. The monthly mean long- and shortwave components of the surface cloud radiative effect obtained from the ERA-Interim reanalysis are about twice that calculated on the basis of CloudSat retrievals. We discuss these discrepancies in terms of instrument-, retrieval- and reanalysis characteristics.

 References Abbot, D. S., Walker, C. C., and Tziperman, E.: Can a convective cloud feedback help to eliminate winter sea ice at high CO<sub>2</sub> concentrations?, J. Clim., 22, 5719–5731, 2009. Arctic Climate Impact Assessment (ACIA), Cambridge University Press, 1042~pp., 2005. Curry, J. A.: On the formation of continental polar air, J. Atmos. Sci., 40, 2279–2292, 1983. Curry, J. A. and Herman, G. F.: Infrared radiative properties of Arctic stratus clouds, J. Clim. Appl. Meteorol., 24, 525–538, 1985. Curry, J. A., Rossow, W. B., Randall, D., and Schramm, J. L.: Overview of Arctic cloud and radiation characteristics, J. Clim., 9, 1731–1763, 1996. Cuzzone, J. and Vavrus, S.: The relationships between Arctic sea ice and cloud-related variables in the ERA-Interim reanalysis and CCSM3, Environ. Res. Lett., 6, 014016, 2011. Eastman, R. and Warren, S. G.: Arctic cloud changes from surface and satellite observations, J. Clim., 23, 4233–4242, 2010. Garrett, T. J. and Zhao, C.: Increased Arctic cloud longwave emmisivity associated with pollution from mid-latitudes, Nature, 440, 787–789, 2006. Gillett, N. P., Stone, D. A., Stott, P. A., Nozawa, T., Karpechko, A. Y., Hegerl, G. C., Wehner, M. F., and Jones, P. D. Attribution of polar warming to human influence, Nat. Geosci., 1, 750–754, 2008. Graversen, R. G., Mauritsen, T., Tjernström, M., Källén, E., and Svensson, G.: Vertical structure of recent Arctic warming, Nature, 451, 53–56, 2008. Held, I. M.: The tropospheric lapse rate and climate sensitivity: Experiments with a two-layer atmospheric model, J. Atmos. Sci., 35, 2083–2098, 1979. % Held, I. M. and Soden, B. J. Water vapor feedback and global warming. Annu. Rev. Energy Environ., 25, 441–475 (2000). Herman, G. F. and Goody, R.: Formation and persistence of summertime Arctic stratus clouds, J. Atmos. Sci., 33, 1537–1553, 1976. Holland, M. M. and Bitz, C. M.: Polar amplification of climate change in coupled models, Clim. Dyn. 21, 221–232, 2003. Huschke, R. E.: Arctic cloud statistics from "Air-Calibrated" surface weather observations, Rand Corp. Memo., RM-6173-PR, Santa Monica, California, 79~pp., 1969. Intrieri, J. M., Fairall, C. W., Shupe, M. D., Persson, P. O. G., Andreas, E. L., Guest, P. S., and Moritz, R. E.: An annual cycle of Arctic surface cloud forcing at SHEBA, J. Geophys. Res., 107, C10, http://dx.doi.org/10.1029/2000JC000439doi:10.1029/2000JC000439, 2002a. Intrieri, J. M., Shupe, M. D., Uttal, T., and McCarthy, B. J.: An annual cycle of Arctic cloud characteristics observed by radar and lidar at SHEBA, J. Geophys. Res. 107, C10, http://dx.doi.org/10.1029/2000JC000423doi:10.1029/2000JC000423, 2002b. Kahl, J. D. W., Martinez, D. A., and Zaitseva, N. A.: Long-term variability in the low-level inversion layer over the Arctic Ocean, Int. J. Clim., 16, 1297–1313, 1996. Kaleschke, L., Lüpkes, C., Vihma, T., Haarpaintner, J., Bochert, A., Hartmann, J., and Heygster, G.: SSM/I sea ice remote sensing for mesoscale ocean-atmosphere interaction analysis, Can. J. Remote Sens. 27, 526–537, 2001. Karlsson, J. and Svensson, G.: The simulation of Arctic clouds and their influence on winter surface temperature in present-day climate in the CMIP3 multi-model dataset, Clim. Dyn., 36, 623–635, http://dx.doi.org/10.1007/s00382-010-0758-6doi:10.1007/s00382-010-0758-6, 2011. Kaspar, F., Hollmann, R., Lockhoff, M., Karlsson, K.-G., Dybbroe, A., Fuchs, P., Selbach, N., Stein, D., and Schulz, J.: Operational generation of AVHRR-based cloud products for Europe and the Arctic at EUMETSATs Satellite Application Facility on Climate Monitoring (CM-SAF), Adv. Sci. Res. 3, 45–51, 2009. Kay, J. E. and Gettelman, A.: Cloud influence on and response to seasonal Arctic sea ice loss, J. Geophys. Res., 114, D18204, http://dx.doi.org/10.1029/2009JD011773doi:10.1029/2009JD011773, 2009. L'Ecuyer, T. S.: Level 2 Fluxes and Heating Rates Product, Process Description and Interface Control Document, Version 5.1. Cooperative Institute for Research in the Atmosphere, Colorado State University, available at: http://cloudsat.cira.colostate.edu/ICD/2B-FLXHR/2B-FLXHR_PDICD_5.1.pdf, 2007. L'Ecuyer, T. S., Wood, N. B., Haladay, T., Stephens, G. L., and Stackhouse, P. W.: Impact of clouds on atmospheric heating based on the R04 CloudSat fluxes and heating rates data set, J. Geophys. Res., 113, D00A15, http://dx.doi.org/10.1029/2008JD009951doi:10.1029/2008JD009951, 2008. Lubin, D. and Vogelmann, A. M.: A climatologically significant aerosol longwave indirect effect in the Arctic, Nature, 439, 453–456, 2006. Mace, G.: Level 2 Radar-Lidar Geoprof Product, Process Description and Interface Control Document, Version 0 – Draft. California Institute of Technology, Pasadena, California, 2003. Mace, G.: A NASA Earth System Science Pathfinder Mission, CloudSat Standard data Products Handbook. Cooperative Institute for Research in the Atmosphere, Colorado State University, 2008. Manabe, S. and Wetherald, R. T. The effects of doubling the CO<sub>2</sub> concentration on the climate of a general circulation model, J. Atmos. Sci., 32, 3–15, 1975. Manabe, S. and Wetherald, R. T.: On the distribution of climate change resulting from an increase in CO<sub>2</sub> content of the atmosphere, J. Atmos. Sci., 37, 99–118, 1980. %Mauritsen, T., Sedlar, J., %Tjernströ m, M., Leck, C., Martin, M., Shupe, M. and Sjogren, S. and % Sierau, B. and Persson, P. O. G. and Brooks, I. M. and Swietlicki, E. An Arctic % CCN-limited cloud-aerosol regime. Atmos. Chem. Phys. 11, 165–173, doi:10.5194/acp-11-165-2011 (2011). Mauritsen, T., Sedlar, J., Tjernström, M., Leck, C., Martin, M., Shupe, M., Sjogren, S., Sierau, B., Persson, P. O. G., Brooks, I. M., and Swietlicki, E.: An Arctic CCN-limited cloud-aerosol regime, Atmos. Chem. Phys., 11, 165–173, http://dx.doi.org/10.5194/acp-11-165-2011doi:10.5194/acp-11-165-2011, 2011. Min, S. K., Zhang, X., Zwiers, F. W., and Agnew, T.: Human influence on Arctic sea ice detectable from early 1990s onwards. Geophys. Res. Lett., 35, L21701, http://dx.doi.org/10.1029/2008GL035725doi:10.1029/2008GL035725, 2008. Partain, P.: CloudSat Project, A NASA Earth System Science Pathfinder Mission, CloudSat ECMWF-AUX Auxillary Data, Process Description and Interface Control Document, Version 3.0. Cooperative Institute for Reasearch in the Atmosphere, Colorado State University, 2004. Ramanathan, V.: Interactions between ice-albedo, lapse-rate and cloud-top feedbacks: An analysis of the nonlinear response of a GCM climate model, J. Atmos. Sci., 34, 1885–1897, 1977. Ramanathan, V., Cess, R. D., Harrison, E. F., Minnis, P., Barkstrom, B. R., Ahmed, E., and Hartmann, D.: Cloud-radiative forcing and climate: Results from the Earth Radiation Budget Experiment, Science, 243, 57–63, 1989. Schneider, S. H.: Cloudiness as a global climatic feedback mechanism: The effects on the radiation balance and surface temperature of variations in cloudiness, J. Atmos. Sci., 29, 1413–1422, 1972. Schweiger, A. J. and Key, J. R.: Arctic Cloudiness: Comparison of ISCCP-C2 and Nimbus-7 satellite derived cloud products with a surface based on cloud climatology, J. Clim., 5, 1514–1527, 1992. Sedlar, J., Tjernström, M., Mauritsen, T., Shupe, M. D., Brooks, I. M., Persson, P. O. G., Birch, C. E., Leck, C., Sirevaag, A., and Nicolaus, M.: A transitioning Arctic surface energy budget: the impacts of solar zenith angle, surface albedo and cloud radiative forcing, Clim. Dyn., 37, 1643–1660,, http://dx.doi.org/10.1007/s00382-010-0937-5doi:10.1007/s00382-010-0937-5, 2010. Serreze, M. C. and Francis, J.: The Arctic amplification debate, Clim. Change, 76, 241–264, 2006. Serreze, M. C., Holland, M. M., and Stroeve, J.: Perspectives on the Arctic's rapidly shrinking sea-ice cover, Science, 315, 1533–1536, 2007. Shupe, M. and Intrieri, J.: Cloud radiative forcing of the arctic surface: The influence of cloud properties, surface albedo and solar zenith angle, J. Clim., 17, 616–628, 2004. Simmons, A., Uppala, S., Dee, D., and Kobayashi, S.: ERA-Interim: new ECMWF reanalysis products from 1989 onwards, ECMWF Newslett. 110, 25–35, 2006. Soden, B. J. and Vecchi, G. A.: The vertical distribution of cloud feedback in coupled ocean-atmosphere models, Geophys. Res. Lett. 38, L12704, http://dx.doi.org/10.1029/2011GL047632doi:10.1029/2011GL047632, 2011. Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, K. B., Tignor, M., and Miller, H. L.: Climate change 2007: The physical science basis. Cambridge University Press, 996~pp., 2007. Stephens, G. L., Vane, D. G., Boain, R. J., Mace, G. G., Sassen, K., Wang, Z., Illingworth, A. J., O'Connor, E. J., Rossow, W. B., Durden, S. L., Miller, S. D., Austin, R. T., Benedetti, A., Mirescu C., and the CloudSat Team: The CloudSat mission and the A-Train, Bull. Amer. Meteorol. Soc., 83, 12, 1771–1790, http://dx.doi.org/10.1175/BAMS-83-12-1771doi:10.1175/BAMS-83-12-1771, 2002. Stephens, G. L., Vane, D. G., Tanelli, S., Im, E., Durden, S., Rokey, M., Reinke, D., Partain, P., Mace, G. G., Austin, R. T., L'Ecuyer, T. S., Haynes, J., Lebsock, M., Suzuki, K., Waliser, D., Wu, D. Kay, J., Gettelman, A., Wang, Z., and Marchand, V.: CloudSat mission: Performance and early science after the first year of operation, J. Geophys. Res., 113, D00A18, http://dx.doi.org/10.1029/2008JD009982doi:10.1029/2008JD009982, 2008. Stroeve, J., Holland, M. M., Meier, W., Scambos, T. and Serreze, M.: Arctic sea ice decline: Faster than forecast, Geophys. Res. Lett. 34, L09501, http://dx.doi.org/10.1029/2007GL029703doi:10.1029/2007GL029703, 2007. Uttal, T., Curry, J.A. , McPhee, M G., Perovich, D K., Moritz, R E., Maslanik, J A., Guest, P S., Stern, H L., Moore, J A. , Turenne, R., Heiberg, A., Serreze, M C., Wylie, D P., Persson, P O G. , Paulson, C A. , Halle, C. , Morrison , J H. , Wheeler P A. , Makshtas, A. , Welch H. , Shupe, M D. , Intrieri J M., Stamnes K., Lindsey R W., Pinkel, R., Pegau, W S., Stanton, T P., and Grenfeld T C.: Surface heat budget of the Arctic ocean, Bull. Amer. Meteorol. Soc., 83, 255–275, 2002. Vavrus, S., Holland, M. M., and Bailey, D. A.: Changes in Arctic clouds during intervals of rapid sea ice loss, Clim. Dyn., 36, 1475–1489, http://dx.doi.org/10.1007/s00382-010-0816-0doi:10.1007/s00382-010-0816-0, 2011. Walsh, J. E. and Chapman, W. L.: Arctic cloud-radiation-temperature associations in observational data and atmospheric reanalysis, J. Clim., 11, 3030–3045, 1998. Winker, D., Hund, W. H., and Gill, M. C.: Initial performance assessment of CALIOP, Geophys. Res. Lett., 34, L19803, 2007. Wetherald, R. T. and Manabe, S.: Cloud feedback processes in a general circulation model, J. Atmos. Sci., 45, 1397–1415, 1988.