About Axel Schweiger Dr. Schweiger's research focuses on ways to impove estimates of the surface radiation balance in the Arctic. To this end he has been developing and evaluating satellite-based algorithms. He has been assembling the TOVS Polar Pathfinder data set, a 20-year data set of polar temperature, humidity profiles and cloud information. He is currently working on applications of this data set to derive radiative fluxes and investigates their role in climate variability through sea ice model experiments. Previous research includes work on microwave-based sea ice concentration algorithms and the application of artificial intelligence methods to remote sensing problems. Dr. Schweiger has been with the Polar Science Center since 1992.

Publications

R.W. Lindsay, J. Zhang, A. Schweiger, M.A. Steele and H. Stern. Arctic Sea Ice Retreat in 2007 Follows Thinning Trend. Journal of Climate 2008, accepted

Schweiger, A.J. , J. Zhang, R.W. Lindsay and M. Steele. (in press). Did unusually sunny skies help drive the sea ice anomaly of 2007. GRL , 2008 in press

Schweiger, A. J., R.W. Lindsay, S. Vavrus and J. A. Francis. "Relationships between Arctic Sea Ice and Clouds during Autumn", Journal of Climate, 2008 in press

Zhang, J, R.W Lindsay, M. Steele and A. Schweiger. “What Drove the Dramatic Retreat of Arctic Sea Ice During Summer 2007?" Geophysical Research Letters, 2008 in press

Zhang J., M. Steele, R. Lindsay, A. Schweiger, J. Morison, Ensemble 1-Year predictions of Arctic sea ice for the spring and summer of 2008, Geophys. Res. Lett., 35, L08502, doi:10.1029/2008GL033244, 2008

Lindsay, R. W., J. Zhang. A. J Schweiger and M. Steele., Seasonal predictions of ice extent in the Arctic Ocean, J.Geophys.Res., 113(C2), 2008

Perovich D.K., S.V. Nghiem, T. Markus, A. Schweiger, "Seasonal evolution and interannual variability of the local solar energy absorbed by the Arctic sea ice-ocean system", J. Geophys. Res.-Oceans 112 (C3): Art. No. C03005, 2007.

Liu, Y.H., J.R. Key, A. Schweiger, and J.A. Francis, "Characteristics of satellite-derived clear-sky atmospheric temperature inversion strength in the Arctic, 1980-96", Journal of Climate (19): 4902-4913, 2006.

Schweiger, A. J. Changes in seasonal cloud cover over the Arctic seas from satellite and surface observations (PDF), Geophysical Research Letters, Vol 31, L12207, doi:10.1029/2004GL020067, 2004.

Schweiger, A. J., R. W. Lindsay, J. A. Francis, J. Key, J. M. Intrieri, and M. D. Shupe, Validation of TOVS Path-P data during SHEBA, J. Geophys. Res., 107(C10), 8041, doi:10.1029/2000JC000453, 2002.

Francis, J. A. and A. J. Schweiger. (2000). A New Window Opens on the Arctic, Eos, Transactions, American Geophysical Union, Vol. 81, No.8, February, 22, 2000, Pages 77,83.

A. J. Schweiger, R.W. Lindsay, J.R. Key, and J.A. Francis. 1999, Arctic Clouds in Multiyear Data Sets. Geophysical Research Letters. 26(13), 1,845-48.

Key, J. R., and A.J. Schweiger. 1998. Tools for Atmospheric Radiative Transfer: Streamer and FluxNet. Computers & Geosciences, Vol. 24. No. 5, pp 443-451.

R. Kwok, A. Schweiger, D. A. Rothrock, S. Pang and C. Kottmeier (1998). Assessment of Sea Ice Motion from Sequential Passive Microwave Observations with ERS and Buoy Ice Motions. Journal of Geophysical Research. Vol 103, C4, 8191-8214.

Key, J. R. , A. J. Schweiger and R. S. Stone. (1997). Expected Uncertainty in Satellite-Derived Estimates of the Surface Radiation Budget at High Latitudes. Journal of Geophysical Research. (Oceans) Vol. 102, No.C7, 15,837-15,847

Schweiger, A. J. and J. Key. 1997. Estimating surface radiation fluxes in the Arctic from TOVS HIRS and MSU brightness Temperatures. International Journal of Remote Sensing. Vol 18., No. 4, 955-970

Lindsay, R.W. , J.A. Francis, P.O.G. Person, D.A. Rothrock and A.J. Schweiger. 1997. Surface Turbulent Fluxes over Pack Ice Inferred from TOVS observations. Annals of Glaciology. Vol. 25, 393-399.

Schweiger, A. J. and J. Key. 1994. Arctic Ocean Radiative Fluxes and Cloud Forcings estimated from the ISCCP C2 Cloud Dataset, 1983-1990. Journal of Applied Meteorology. Vol.33, No. 8, 948-963

Schweiger, A. J., J. Key and M.C. Serreze. 1993. Arctic Sea Ice Albedo. A Comparison of two Satellite-Derived Data Sets. Geophysical Research Letter, Vol. 20, No. 1., 41-44.

Key, J., J. A. Maslanik, T. Papakryriakou, M.C. Serreze and A. J. Schweiger. 1993. On the Validation of Satellite-derived Sea Ice Surface Temperature. Arctic.

Schweiger, A.J., Key, J. 1992. Comparison of ISCCP-C2 and Nimbus-7 satellite-derived cloud products with a surface-based cloud climatology in the Arctic. Journal of Climate. Vol.5 No. 12, 1514-1527)

Steffen, K., Schweiger, A.J. 1991. NASA Team Algorithm for Sea Ice Concentration Retrieval from Defense Meteorological Satellite Program Special Sensor Microwave Imager: Comparison with Landsat Satellite Imagery. Journal of Geophysical Research, Vol. 96, no. C12, 21,971 - 21,987.

Steffen, K., Schweiger, A. J. 1990. A Multisensor Approach to Sea Ice Classification for the Validation of DMSP-SSM/I Passive Microwave Derived Sea Ice Products.Photogrammetric Engineering and Remote Sensing. Vol 56, No. 1, 75-82.

Schweiger, A.J., Barry, R.G. 1989. Evaluation of algorithms for mapping snow cover parameters in the Federal Republic of Germany using passive microwave data. Erdkunde, B 43/89.

Key. J, Maslanik,J.A., and Schweiger,A.J.1989. Classification of merged AVHRR and SMMR arctic data with Neural Networks. Photogrammetric Engineering and Remote Sensing, Vol. 55, No. 9, 1331-1338.

McGuffie, K., Barry, R.G., Schweiger, A.J., Robinson, D.A., and Newell, J. 1988. Intercomparison of satellite derived cloud analyses for the arctic ocean in spring and summer. International Journal of Remote Sensing, 9(3), 447-467.

Barry, R.G., Crane, R.G., Schweiger, A.J. and Newell, J. 1987. Arctic cloudiness in spring from satellite imagery. Journal of Climatology, Vol. 7, 423-451.

Schweiger, A.J., Armstrong, R. and Barry, R.G. 1987. Snow cover parameter retrieval from various data sources in the Federal Republic of Germany. In: Large scale effects of seasonal snow cover eds. B.Goodison, R.G.Barry and J.Dozier IAHS publ 166, International Association of Hydrological Sciences Press, 353-364.

PUBLISHED CONFERENCE PAPERS, REPORTS

A. J. Schweiger, C. Fowler, J. Key, J. Maslanik, J. Francis, R. Armstrong, M.J. Brodzik, T. Scambos, T. Haran, M. Ortmeyer, S. Khalsa, D. Rothrock and R. Weaver. (1999). P-Cube: A multisensor data set for polar climate research. To appear in: Proceedings of the Fith Conference on Polar Meteorology and Oceanography, American Meteorological Society, January 10-15, 1999, Dallas, TX.

Francis, J. A. and A. J. Schweiger. (1999). The NASA TOVS Polar Pathfinder. 18 Years of Arctic data. To appear in: Proceedings of the Fith Conference on Polar Meteorology and Oceanography, American Meteorological Society, January 10-15, 1999, Dallas, TX.

Francis, J. A , Schweiger, A. J. and D. Groves. The NASA Polar Pathfinder. 18 Years of Arctic data. To appear in proceedings of the AMS conference, Paris, May, 1998.

Duff, J., Salem, K., Schweiger, A., and Livny, M. (1997). Processing TOVS Polar Pathfinder Data Using the Distributed BatchController,Proc. SPIE, Vol. 3117, pp. 132-142, Earth Observing Systems II,William L. Barnes, Ed.

Schweiger, A.J., Key. J, and Francis. J. 1995. A neural-network based approach to the retrieval of the surface radiation budget of the Arctic from TOVS brigthness temperatures. Techical Proceedings of the Eighth International TOVS Study Conference, Queenstown, NZ, April 4 - 11, 1995

Maslanik, J.A., J. R. Key and A.J. Schweiger. 1995. Cloud amount and radiation: Effects of climatology and method on arctic sea-ice simulations. Proceedings of the Fourth Conference on Polar Meteorology and Oceanography, Dallas Texas, January 15-20, 1995. 168-173

Schweiger, A.J. and A. D. Rothrock. Monitoring sea ice flux through Fram Strait. Proceedings of the 2nd ERS-1 users conference. Hamburg Oct 11-14, 1993

Winebrenner, D., J. Key, A. J. Schweiger, E. Nelson R. Colony, D. Barber and E. LeDrew. 1993. On links between microwave and shortwave signatures of multiyear sea ice during the onset of melt. Proceedings of the Topical Symposium on the Combined Optical-Microwave Earth and Atmosphere Sensing. March 22-25,Albuquerque, NM. 74-77

Serreze, M.C, Schweiger, A.J. and Key, J.R. 1993. Comparison of Two Satellite-Derived Albedo Data Sets for the Arctic Ocean. Snow Watch 92. Glaciological Data Report , GD-25, 172-188.

Steffen. K, Schweiger, A.J. 1992. Ocean Surface Energy Flux Estimates from Satellite Data in Arctic Regions. Proceedings of the Marine Technology Society Conference. Washington, DC. 1992, 434-437.

Schweiger, A.J. and J. Key. 1992. Arctic Radiative Fluxes and Cloud Forcing Estimated from the ISCCP-C2 Cloud Data Set. Proceedings of the Third AMS Conference on Polar Meteorology and Oceanography, Portland Sept. 1992, 13-16.

Steffen, K. and A.J. Schweiger. (1992). SSM/I - Landsat Comparison. In: Cavalieri, D.J (ed.) NASA Sea Ice Validation Program for the Defense Meteorological Satellite Program Special Sensor Microwave Imager: Final Report. NASA Technical Memorandum 104559, 33-46.

Key, J., Schweiger, A.J. and Maslanik,J.A. (forthcoming). Arctic radiation forcing fields for thermodynamic sea ice models. Workshop on sea ice thickness. NASA-GODDARD SFC Nov. 1991

Key, J., Maslanik, J.A. and Schweiger, A.J. 1990. Neural Network vs. Maximum Likelihood Classification of Spectral and Textural Features in Visible, Thermal, and Passive Microwave Data. Proceedings, IGARSS 1990, Vol. 2. 1277-1280.

Key, J., Schweiger, A.J. and Maslanik, J.A. 1990. Mapping Sea Ice with a coupled Numeric/Symbolic System. ACSM/ASPRS Proceedings Vol.4, Denver, Colorado, March 18, 228-237.

Maslanik, J.A., Key, J. and Schweiger, A.J. 1990. Neural Network Identification of SeaIce Seasons in Passive Microwave Data. Proceedings, IGARSS 1990, Vol 2, 281-1284.

Steffen, K., Weaver, R.L. and Schweiger,A.J. 1990. Use of Landsat MSS, TM, NOAA AVHRR Satellite Data, Aircraft Sar and Photography for Validation of Passive Microwave Sea Ice Algorithms. ACMS/ASPRS Proceedings,Annual Convention, Denver, Co. March, 1990

Schweiger, A.J., Maslanik, J.A. and Key. J.R., 1990. Multi-Sensor and Multi-Dimensional Analysis. Addressing problems of classification using Artificial-Intelligence Techniques. Proceedings OCEANS FROM SPACE, VENICE 1990, IAPSO publication

Schweiger, A.J., Steffen, K. 1989. Comparison of sea ice parameters retrieved from passive microwave, Landsat MSS and AVHRR imagery. Proceedings IGARSS 89, Vancouver B.C

Steffen, K., Schweiger, A.J. 1989. Sensitivity of passive microwave sea ice concentration algorithms to the selection of locally and seasonally adjusted tie points. Proceedings IGARSS 89, Vancouver, B.C.

Barry, R.G., and A.J. Schweiger. 1988. Snow cover conditions in northern and central Europe. Final Report to National Science Foundation. April, 1988.

Schweiger, A.,J. 1987. Retrieval of snow cover parameters using passive microwave radiometry in the Federal Republic of Germany. M.A. Thesis, University of Colorado.

Schweiger, A. J. 1987. A bibliography of snow and ice on highways. NHRAIC Topical Biblio-graphy No. 13. Natural Hazards Research and Applications Center, University. of. Colorado.

PUBLISHED ABSTRACTS/ADDITIONAL CONFERENCE PRESENTATIONS

Schweiger, A. J. and Francis, J. 1995. TOVS Path-P: A new TOVS-based data set for Arctic Research. Technical Proceedings of the Eighth Internationalt TOVS Study Conference. Queenstown, NZ. April 4-11, 1995

Francis, J., Schweiger, A, J. and Rothrock, D.A. 1995. TOVS Path-P: A Pathfinder Data Set of Atmospheric and Surface Variables for Process and Climate Studied of the Arctic Basin. American Geophysical Union, Baltimore, May 29-June 1, EOS.

Steffen., K., Schweiger, A.J. 1992. Bidirectional spectral reflectance of snow: Comparison of field measurements on the Greenland ice sheet with Model Calculations. International Glaciological Society Symposium on Remote Sensing of Snow and Ice. May 1992.

Schweiger, A.J., Key, J. and Haefliger, M. 1991. Arctic radiative fluxes and cloud forcings estimated from the ISCCP-C2 cloud data set, 1983-9186. American Geophysical Union, San Francisco, December, 9-13, EOS, October 29, 238.

Schweiger, A. J., 1987. Snow cover parameter retrieval from the SMMR microwave sensor in northern and central Europe. Association of American Geographers Annual Meeting, Portland, Or. April 1987.

Schweiger, A.J., Armstrong, R. and Barry, R.G.,1987 Snow cover parameter retrieval from various data sources in the Federal Republic of Germany. IAHS conference, Vancouver. BC 1987.