Estimating Longwave Net Radiation at Sea Surface from the Special Sensor Microwave/Imager (SSM/I)

Quanhua Liu Institute for Marine Sciences, Kiel, Germany

Search for other papers by Quanhua Liu in
Current site
Google Scholar
PubMed
Close
,
Clemens Simmer Institute for Marine Sciences, Kiel, Germany

Search for other papers by Clemens Simmer in
Current site
Google Scholar
PubMed
Close
, and
Eberhard Ruprecht Institute for Marine Sciences, Kiel, Germany

Search for other papers by Eberhard Ruprecht in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

A neural network is used to calculate the longwave net radiation (Lnet) at the sea surface from measurements of the Special Sensor Microwave/Imager (SSM/I). The neural network applied in this study is able to account largely for the nonlinearity between Lnet and the satellite-measured brightness temperatures (TB). The algorithm can be applied for instantaneous measurements over oceanic regions with the area extent of satellite passive microwave observations (30–60 km in diameter). Comparing with a linear regression method the neural network reduces the standard error for Lnet from 17 to 5 W m−2 when applied to model results. For clear-sky cases, a good agreement with an error of less than 5 W m−2 for Lnet between calculations from SSM/I observations and pyrgeometer measurements on the German research vessel Poseidon during the International Cirrus Experiment (ICE) 1989 is obtained. For cloudy cases, the comparison is problematic due to the inhomogenities of clouds and the low and different spatial resolutions of the SSM/I data. Global monthly mean values of Lnet for October 1989 are computed and compared to other sources. Differences are observed among the climatological values from previous studies by H.-J. Isemer and L. Hasse, the climatological values from R. Lindau and L. Hasse, the values of W. L. Darnell et al., and results from this study. Some structures of Lnet are similar for results from W. L. Darnell et al. and the present authors. The differences between both results are generally less than 15 W m−2. Over the North Atlantic Ocean the authors found a poleward increase for Lnet, which is contrary to the results of H.-J. Isemer and L. Hasse.

Corresponding author address: Dr. Quanhua Liu, Institute for Marine Sciences, Düsternbrooker Weg 20, 24105 Kiel, Germany.

Abstract

A neural network is used to calculate the longwave net radiation (Lnet) at the sea surface from measurements of the Special Sensor Microwave/Imager (SSM/I). The neural network applied in this study is able to account largely for the nonlinearity between Lnet and the satellite-measured brightness temperatures (TB). The algorithm can be applied for instantaneous measurements over oceanic regions with the area extent of satellite passive microwave observations (30–60 km in diameter). Comparing with a linear regression method the neural network reduces the standard error for Lnet from 17 to 5 W m−2 when applied to model results. For clear-sky cases, a good agreement with an error of less than 5 W m−2 for Lnet between calculations from SSM/I observations and pyrgeometer measurements on the German research vessel Poseidon during the International Cirrus Experiment (ICE) 1989 is obtained. For cloudy cases, the comparison is problematic due to the inhomogenities of clouds and the low and different spatial resolutions of the SSM/I data. Global monthly mean values of Lnet for October 1989 are computed and compared to other sources. Differences are observed among the climatological values from previous studies by H.-J. Isemer and L. Hasse, the climatological values from R. Lindau and L. Hasse, the values of W. L. Darnell et al., and results from this study. Some structures of Lnet are similar for results from W. L. Darnell et al. and the present authors. The differences between both results are generally less than 15 W m−2. Over the North Atlantic Ocean the authors found a poleward increase for Lnet, which is contrary to the results of H.-J. Isemer and L. Hasse.

Corresponding author address: Dr. Quanhua Liu, Institute for Marine Sciences, Düsternbrooker Weg 20, 24105 Kiel, Germany.

Save
  • Anderson, E. R., 1952: Energy budget studies. U.S. Geol. Surv. Circ.,229, 71–119.

  • Bauer, P., and P. Schluessel, 1993: Rainfall, total water, ice water, and water vapor over sea from polarized microwave simulations and Special Sensor Microwave/Imager data. J. Geophys. Res.,98, 20 737–20 759.

  • Bignami, F., R. Santoleri, M. Schiano, and S. Marullo, 1991: Net longwave radiation in the western Mediterranean Sea. Poster Session at the 20th General Assembly of the International Union of Geodesy and Geophysics, Vienna, Austria, IAPSO.

  • Budyko, M. I., 1974: Climate and Life. International Geophysics Series, Vol. 18, Academic Press, 508 pp.

  • Chen, K. S., W. L. Kao, and Y. C. Tzeng, 1995: Retrieval of surface parameters using dynamic learning neural network. Int. J. Remote Sens.,16, 801–809.

  • Crewell, S., E. Ruprecht, and C. Simmer, 1991: Latent heat flux over the North Atlantic Ocean—A case study. J. Appl. Meteor.,30, 1627–1635.

  • Darnell, W. L., W. F. Staylor, S. K. Gupta, N. A. Ritchey, and A. C. Wilber, 1992: Seasonal variation of surface radiation budget derived from International Satellite Cloud Climatology Project C1 data. J. Geophys. Res.,97, 15 741–15 760.

  • Fung, I. Y., D. E. Harrison, and A. A. Lacis, 1984: On the variability of the net longwave radiation at the ocean surface. Rev.Geophys.,22, 177–193.

  • Gilman, C., and C. Carrett, 1994: Heat flux parameterizations for the Mediterranean Sea: The role of atmospheric aerosols and constraints from the water budget. J. Geophys. Res.,99, 5119–5134.

  • Goodberlet, M. A., C. I. Swift, and I. C. Wilheon, 1990: Ocean surface wind speed measurements of the special microwave imager (SSM/I). IEEE Trans. Geosci. Remote Sens.,GE-28, 823–827.

  • Greenwald, T., G. L. Stephens, T. H. Vonder Haar, and D. L. Jackson, 1993: A physical retrieval of cloud liquid water over the global oceans using Special Sensor Microwave/Imager (SSM/I) observations. J. Geophys. Res.,98, 18 471–18 488.

  • Gupta, S. K., 1989: A parameterization for longwave surface radiation from sun-synchronous satellite data. J. Climate,2, 305–320.

  • Haferman, J. L., E. N. Anagnostou, D. Tsintikidis, W. F. Krajewski, and T. F. Smith, 1996: Physically based satellite retrieval of precipitation using a 3D passive microwave radiative transfer model. J. Atmos. Oceanic Technol.,13, 832–850.

  • Hennings, D., M. Quante, and R. Sefzig, 1990: International Cirrus Experiment 1989 Field Phase Report, 129 pp. [Available from Institute of Geophysics and Meteorology, University of Cologne, Cologne, Germany.].

  • Hertz, J., A. Krogh, and R. G. Palmer, 1991: Introduction to the Theory of Neural Computation. Addison-Wesley, 327 pp.

  • Isemer, H.-J., and L. Hasse, 1985: The Bunker Climate Atlas of the North Atlantic Ocean. Vol. 1, Observations, Springer-Verlag, 218 pp.

  • Karstens, U., C. Simmer, and E. Ruprecht, 1994: Remote sensing of cloud liquid water. Meteor. Atmos. Phys.,54, 157–171.

  • Liebe, H. J., 1985: An updated model for millimeter wave propagation in moist air. Radio Sci.,20, 1069–1089.

  • Lindau, R., and L. Hasse, 1997: COADS Climate Atlas of the Atlantic Ocean. Springer-Verlag, in press.

  • Liou, K. N., 1980: An Introduction to Atmospheric Radiation. Academic Press, 392 pp.

  • ——, 1986: Influence of cirrus clouds on weather and climate processes: A global perspective. Mon. Wea. Rev.,114, 1167–1199.

  • Liu, G., and J. A. Curry, 1992: Retrieval of precipitation from satellite microwave measurement using both emission and scattering. J. Geophys. Res.,97, 9959–9974.

  • Liu, Q., and E. Ruprecht, 1996: A radiative transfer model: Matrix operator method. Appl. Opt.,35, 4229–4237.

  • Petty, G. W., 1994: Physical retrievals of over-ocean rain rate from multichannel microwave imagery. Part II: Algorithm implementation. Meteor. Atmos. Phys.,54, 101–122.

  • Ramanathan, V., 1986: Scientific use of surface radiation budget data for climate studies. Position Paper in NASA RP-1169, 132 pp.

  • Schmetz, J., 1986: An atmospheric-correction scheme for operational application to METEOSAT infrared measurements. ESA,10, 145–159.

  • ——, 1989: Towards a surface radiation climatology: Retrieval of downward irradiances from satellites. Atmos. Res.,23, 287–321.

  • Simmer, C., 1994: Satellitenfernerkundung Hydrologischer Parameter der Atmosphäre mit Mikrowellen. Verlag, 313 pp.

  • Smith, W. L., and H. M. Woolf, 1983: Geostationary satellite sounder (VAS) observations of longwave radiation flux. Paper Presented at the Satellite Systems to Measure Radiation Budget Parameters and Climate Change Signal, Igls, Austria, International Radiation Commission.

  • Stephens, G. L., D. L. Jackson, and J. J. Bates, 1994: A comparison of SSM/I and TOVS column water data over the global oceans. Meteor. Atmos. Phys.,54, 183–201.

  • Tsang, L., Z. X. Chen, S. Oh, R. J. Marks, and A. T. C. Chang, 1992: Inversion of snow parameters from passive microwave remote sensing measurements by a neural network trained with a multiple scattering model. IEEE Trans. Geosci. Remote Sens.,30, 1015–1024.

  • Weng, F. Z., and N. Grody, 1994: Retrieval of cloud water using the Special Sensor Microwave Imager (SSM/I). J. Geophys. Res.,99, 25 535–25 551.

  • Wentz, F. J., 1992: Measurement of oceanic wind vector using satellite microwave radiometers. IEEE Trans. Geosci. Remote Sens.,30, 960–972.

  • Wisler, M. M., and J. P. Hollinger, 1977: Estimation of marine environmental parameters using microwave radiometric remote sensing systems. N.R.L. Memo. Rep. 3661, 27 pp.

  • Zhi, H., and Harshvardhan, 1993: A hybrid technique for computing the monthly mean net longwave surface radiation over oceanic areas. Theor. Appl. Climatol.,47, 65–79.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 1106 703 35
PDF Downloads 211 46 7