Atmospheric Chemistry and Physics
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8
2
2008
10.5194/acp-8-309-2008
http://www.atmos-chem-phys.net/8/309/2008/
http://www.atmos-chem-phys.net/8/309/2008/acp-8-309-2008.html
http://www.atmos-chem-phys.net/8/309/2008/acp-8-309-2008.pdf
309
320
2008-01-25
Comparison of satellite limb-sounding humidity climatologies of the uppermost tropical troposphere
M. Ekström
mattias.ekstrom@chalmers.se
P. Eriksson
W. G. Read
M. Milz
D. P. Murtagh
Department of Radio and Space Science, Chalmers University of Technology, Gothenburg, Sweden
Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA
Department of Space Science, Luleå Technical University, Kiruna, Sweden
formerly at: Institut für Meteorologie und Klimaforschung, Universität Karlsruhe (TH)/Forschungszentrum Karlsruhe, Karlsruhe, Germany
Humidity climatologies of the tropical uppermost troposphere from satellite
limb emission measurements have been compared. Four instruments are
considered; UARS-MLS, Odin-SMR, and Aura-MLS operating in the microwave
region, and MIPAS in the infrared region. A reference for the comparison is
obtained by MOZAIC in-situ measurements.
<br><br>
The upper tropospheric humidity products were compared on basis of their
empirical probability density functions and seasonally averaged horizontal
fields at two altitude layers, 12 and 15 km. The probability density
functions of the microwave datasets were found to be in very good agreement
with each other, and were also consistent with MOZAIC. The average seasonal
humidities differ with less than 10%RHi between the instruments, indicating
that stated measurement accuracies of 20–30% are conservative estimates.
The systematic uncertainty in Odin-SMR data due to cloud correction was also
independently estimated to be 10%RHi. MIPAS humidity profiles were found to
suffer from cloud contamination, with only 30% of the measurements reaching
into the upper troposphere, but under clear-sky conditions there is a good
agreement between MIPAS, Odin-SMR and Aura-MLS.
<br><br>
Odin-SMR and the two MLS datasets can be treated as independent, being based
on different underlying spectroscopy and technology. The good agreement
between the microwave limb-sounders, and MOZAIC, is therefore an important
step towards understanding the upper tropospheric humidity. The found
accuracy of 10%RHi is approaching the level required to validate climate
modelling of the upper troposphere humidity. The comparison of microwave and
infrared also stresses that microwave limb-sounding is necessary for a complete
view of the upper troposphere.
Barath, F T., Chavez, M C., Cofield, R E., Flower, D A., Frerking, M A., Gram, M B., Harris, W M., Holden, J R., Jarnot, R F., Kloezeman, W G., Klose, G J., Lau, G K., Loo, M S., Maddison, B J., Mattauch, R J., McKinney, R P., Peckham, G E., Pickett, H M., Siebes, G., Soltis, F S., Suttie, R A., Tarsala, J A., Waters, J W., and Wilson, W J.: The Upper Atmosphere Research Satellite microwave limb sounder instrument, J. Geophys. Res., 98, 10 751–10 762, 1993.
Bates, J J. and Jackson, D L.: Trends in upper-tropospheric humidity, Geophys. Res. Lett., 28, 1695–1698, 2001.
Buehler, S A. and Courcoux, N.: The impact of temperature errors on perceived humidity supersaturation, Geophys. Res. Lett., 30, 1759, \doi10.1029/2003GL017691, 2003.
Croskey, C L., Kämpfer, N., Belivacqua, R M., Hartmann, G K., Kunzi, K F., Schwartz, P R., Olivero, J J., Puliafito, S E., Aellig, C., Umlauft, G., Waltman, W B., and Degenhardt, W.: The Millimeter Wave Atmospheric Sounder (MAS): A Shuttle-Based Remote Sensing Experiment, IEEE Trans. Microwave Theory Techn., 40, 1090–1100, 1992.
Ekström, M., Eriksson, P., Rydberg, B., and Murtagh, D P.: First Odin sub-mm retrievals in the tropical upper troposphere: humidity and cloud ice signals, Atmos. Chem. Phys., 7, 459–469, 2007.
Eriksson, P., Ekström, M., Rydberg, B., and Murtagh, D P.: First Odin sub-mm retrievals in the tropical upper troposphere: ice cloud properties, Atmos. Chem. Phys., 7, 471–483, 2007.
Fischer, H. and Oelhaf, H.: Remote Sensing of vertical profiles of atmospheric trace constituents with MIPAS limb emission spectrometers, Appl. Optics, 35, 2787–2796, 1996.
Frisk, U., Hagström, M., Ala-Laurinaho, J., Andersson, S., Berges, J C., Chabaud, J P., Dahlgren, M., Emrich, A., Florén, H G., Fredrixon, M., Gaier, T., Haas, R., Hirvonen, T., Hjalmarsson, A., Jakobsson, B., Jukkala, P., Kildal, P S., Kollberg, E., Lassing, J., Lecacheux, A., Lehikoinen, P., Lehto, A., Mallat, J., Marty, C., Michet, D., Narbonne, J., Nexon, M., Olberg, M., Olofsson, A. O H., Olofsson, G., Origné, A., Petersson, M., Piironen, P., Pons, R., Pouliquen, D., Ristorcelli, I., Rosolen, C., Rouaix, G., Räisänen, A V., Serra, G., Sjöberg, F., Stenmark, L., Torchinsky, S., Tuovinen, J., Ullberg, C., Vinterhav, E., Wadefalk, N., Zirath, H., Zimmermann, P., and Zimmermann, R.: The Odin satellite I. Radiometer design and test, Astron. Astrophys., 402, L27–L34, \doi10.1051/0004-6361:20030335, 2003.
Gierens, K. and Spichtinger, P.: On the distribution of ice-supersaturated regions in the upper troposphere and lowermost stratosphere, Ann. Geophys., 18, 499–504, 2000.
Gierens, K., Schumann, U., Helten, M., Smit, H., and Marenco, A.: A distribution law for relative humidity in the upper troposphere and lower stratosphere derived from three years of MOZAIC measurements, Ann. Geophys., 17, 1218–1226, 1999.
Gille, J C., Bailey, P L., and Russell, J M.: Temperature and Composition Measurements from the l.r.i.r. and l.i.m.s. Experiments on Nimbus 6 and 7, Phil. Trans. R. Soc. A, 296, 205–218, 1980.
Harries, J E.: Atmospheric radiation and atmospheric humidity, Q. J. Roy. Meteor. Soc., 123, 2173–2186, 1997.
Helten, M., Smit, H. G J., Sträter, W., Kley, D., Nedelec, P., Zöger, M., and Busen, R.: Calibration and preformance of automatic compact instrumentation for the measurement of relative humidity from passenger aircraft, J. Geophys. Res., 103, 25 643–25 652, 1998.
Jensen, E J., Smith, J B., Pfister, L., Pittman, J V., Weinstock, E M., Sayres, D S., Herman, R L., Troy, R F., Rosenlof, K., Thompson, T L., Fridlind, A M., Hudson, P K., Cziczo, D J., Heymsfield, A J., Schmitt, C., and Wilson, J C.: Ice supersaturations exceeding 100% at the cold tropical tropopause: implications for cirrus formation and dehydration, Atmos. Chem. Phys., 5, 851–862, 2005.
Jiang, J H., Wang, B., Goya, K., Hocke, K., Eckermann, S D., Ma, J., Wu, D L., and Read, W G.: Geographical distribution and interseasonal variability of tropical deep convection: UARS MLS observations and analyses, J. Geophys. Res., 109, D03111, 1–19, 2004.
Kley, D., Russell III, J M., and Phillips, C. (Eds.): SPARC Assessment of Upper Tropospheric and Stratospheric Water Vapour, WCRP – No. 113, WMO/TD – No. 1043, SPARC Report No. 2, Paris, 2000.
Lary, D J. and Lait, L.: Using Probability Distribution Functions for Satellite Validation, IEEE Trans. Geosci. Rem. Sens., 44, 1359–1366, 2006.
List, R J.: Smithsonian Meteorological Tables, Smithson. Misc. Collect. 114, Smithson. Inst., Washington, D.C., 1951.
Livesey, N J., Read, W G., Froidevaux, L., Waters, J W., Santee, M L., Pumphrey, H C., Wu, D L., Shippony, Z., and Jarnot, R F.: The UARS Microwave Limb Sounder version 5 data set: Theory, characterization, and validation, J. Geophys. Res., 108, 4378, \doi10.1029/2002JD002273, 2003.
Livesey, N J., Snyder, W V., Read, W G., and Wagner, P A.: Retrieval algorithms for the EOS Microwave Limb Sounder (MLS), IEEE Trans. Geosci. Rem. Sens., 44, 1144–1155, \doi10.1109/TGRS.2006.872327, 2006.
Livesey, N J., Read, W G., Lambert, A., Cofield, R E., Cuddy, D T., Froidevaux, L., Fuller, R A., Jarnot, R F., Jiang, J H., Jiang, Y B., Knosp, B W., Kovalenko, L J., Pickett, H M., Pumphrey, H C., Santee, M L., Schwartz, M J., Stek, P C., Wagner, P A., Waters, J W., and Wu, D L.: Earth Observing System (EOS) Microwave Limb Sounder (MLS) Version 2.2 Level 2 data quality and description document, JPL Tech. Doc. D-33509, Jet Propulsion Lab., Pasadena, CA, 2007.
Luo, Z., Kley, D., Johnson, R H., and Smit, H.: Ten Years of Measurements of Tropical Upper-Tropospheric Water Vapor by MOZAIC. Part I: Climatology, Variability, Transport, and Relation to Deep Convection, J. Climate, 20, 418–435, 2007.
Marenco, A., Thouret, V., Nédélec, P., Smit, H., Helten, M., Kley, D., Karcher, F., Simon, P., Law, K., Pyle, J., Poschmann, G., von Wrede, R., Hume, C., and Cook, T.: Measurement of ozone and water vapor by Airbus in-service aircraft: The MOZAIC airborne program, an overwiew, J. Geophys. Res., 103, 25 631–25 642, 1998.
Milz, M., von Clarmann, T., Fischer, H., Glatthor, N., Grabowski, U., Höpfner, M., Kellman, S., Kiefer, M., Linden, A., Tsidu, G M., and Stiller, G P.: Water vapor distributions measured with the Michelson Interferometer for Passive Atmospheric Sounding on board Envisat (MIPAS/Envisat), J. Geophys. Res., 110, D24307, \doi10.1029/2005JD005973, 2005.
Minschwaner, K. and Dessler, A E.: Water vapor feedback in the tropical upper troposphere: Model results and observations, J. Climate, 17, 1272–1282, 2004.
Murtagh, D., Frisk, U., Merino, F., Ridal, M., Jonsson, A., Stegman, J., Witt, G., Eriksson, P., Jiménez, C., Megie, G., de~La~No\"e, J., Ricaud, P., Baron, P., Pardo, J R., Hauchcorne, A., Llewellyn, E J., Degenstein, D A., Gattinger, R L., Lloyd, N D., Evans, W. F J., McDade, I C., Haley, C., Sioris, C., von Savigny, C., Solheim, B H., McConnell, J C., Strong, K., Richardson, E H., Leppelmeier, G W., Kyrölä, E., Auvinen, H., and Oikarinen, L.: An overview of the Odin atmospheric mission, Can. J. Phys., 80, 309–319, 2002.
Nordh, H L., von Schéele, F., Frisk, U., Ahola, K., Booth, R S., Encrenaz, P J., Hjalmarson, A., Kendall, D., Kyrölä, E., Kwok, S., Lecacheux, A., Leppelmeier, G., Llewellyn, E J., Mattila, K., Mégie, G., Murtagh, D., Rougeron, M., and Witt, G.: The Odin orbital observatory, Astron. Astrophys., 402, L21–L25, \doi10.1051/0004-6361:20030334, 2003.
Ovarlez, J., Gayet, J.-F., Gierens, K., Ström, J., Ovarlez, H., Auriol, F., Busen, R., and Schumann, U.: Water vapour measurements inside cirrus clouds in Northern and Southern hemispheres during INCA, Geophys. Res. Lett., 29, 1813, \doi10.1029/2001GL014440, 2002.
Peter, T., Marcolli, C., Spichtinger, P., Corti, T., Baker, M B., and Koop, T.: When Dry Air Is Too Humid, Science, 314, 1399–1402, \doi10.1126/science.1135199, 2006.
Read, W G., Waters, J W., Flower, D A., Froidevaux, L., Jarnot, R F., Hartmann, D L., Harwood, R S., and Rood, R B.: Upper-Tropospheric Water Vapor from UARS MLS, B. Am. Meteorol. Soc., 76, 2381–2389, 1995.
Read, W G., Waters, J W., Wu, D L., Stone, E M., Shippony, Z., Smedley, A C., Smallcomb, C C., Oltmans, S., Kley, D., Smit, H. G J., Mergenthaler, J L., and Karki, M K.: UARS Microwave Limb Sounder upper tropospheric humidity measurement: Method and validation, J. Geophys. Res., 106, 32 207–32 258, 2001.
Read, W G., Lambert, A., Bacmeister, J., Cofield, R E., Christensen, L E., Cuddy, D T., Daffer, W H., Drouin, B J., Fetzer, E., Froidevaux, L., Fuller, R., Herman, R., Jarnot, R F., Jiang, J H., Jiang, Y B., Kelly, K., Knosp, B W., Pumphrey, H C., Rosenlof, K H., Sabounchi, X., Santee, M L., Schwartz, M J., Snyder, W V., Stek, P C., Su, H., Takacs, L L., Thurstans, R P., Vömel, H., Wagner, P A., Waters, J W., Webster, C R., Weinstock, E M., and Wu, D L.: Aura Microwave Limb Sounder upper tropospheric and lower stratospheric H<sub>2</sub>O and relative humidity with respect to ice validation, J. Geophys. Res., 112, D24S35, \doi10.1029/2007JD008752, 2007.
Ridolfi, M., Carli, B., Carlotti, M., Clarmann, T V., Dinelli, B M., Dudhia, A., Flaud, J.-M., Höpfner, M., Morris, P E., Raspollini, P., Stiller, G., and Wells, R J.: Optimized forward model and retrieval scheme for MIPAS near-real-time data processing, Appl. Optics, 39, 1323–1340, 2000.
Sassi, F., Salby, M., and Read, W G.: Relationship between upper tropospheric humidity and deep convection, J. Geophys. Res., 106, 17 133–17 146, 2001.
Sherwood, S C. and Dessler, A E.: On the control of stratospheric humidity, Geophys. Res. Lett., 27, 2513–2516, 2000.
Soden, B J.: The diurnal cycle of convection, clouds, and water vapor in the tropical upper troposphere, Geophys. Res. Lett., 27, 2173–2176, 2000.
Soden, B J. and Bretherton, F P.: Interpolation of TOVS water vapor radiances in terms of layer-average relative humidities: Method and climatology for the upper, middle and lower troposphere, J. Geophys. Res., 101, 9333–9343, 1996.
Soden, B J., Turner, D D., Lesht, B M., and Miloshevich, L M.: An analysis of satellite, radiosonde, and lidar observations of upper tropospheric water vapor from the Atmospheric Radiation Measurement Program, J. Geophys. Res., 109, D04105, doi:10.1029/2003JD003828, 2004.
Sonntag, D.: Advancements in the field of hygrometry, Meteorol. Z., 3, 51–66, 1994.
Spichtinger, P., Gierens, K., and Read, W.: The global distribution of ice-supersaturated regions as seen by the Microwave Limb Sounder, Q. J. Roy. Meteor. Soc., 129, 3391–3410, \doi10.1256/qj.02.141, 2003.
Spichtinger, P., Gierens, K., Smit, H. G J., Ovarlez, J., and Gayet, J.-F.: On the distribution of relative humidity in cirrus clouds, Atmos. Chem. Phys., 4, 639–647, 2004.
Tian, B., Soden, B J., and Wu, X.: Diurnal cycle of convection, clouds, and water vapor in the tropical upper tropopsphere: Satellites versus a general circulation model, J. Geophys. Res., 109, D10101, \doi10.1029/2003JD004117, 2004.
Waters, J W., Froidevaux, L., Harwood, R S., Jarnot, R F., Pickett, H M., Read, W G., Siegel, P H., Cofield, R E., Filipiak, M J., Flower, D A., Holden, J R., Lau, G K., Livesey, N J., Manney, G L., Pumphrey, H C., Santee, M L., Wu, D L., Cuddy, D T., Lay, R R., Loo, M S., Perun, V S., Schwartz, M J., Stek, P C., Thurstans, R P., Boyles, M A., Chandra, K M., Chavez, M C., Chen, G.-S., Chudasama, B., Dodge, R., Fuller, R A., Girard, M A., Jiang, J H., Jiang, Y., Knosp, B W., LaBelle, R C., Lam, J C., Lee, K A., Miller, D., Oswald, J E., Patel, N C., Pukala, D M., Quintero, O., Scaff, D M., Snyder, W V., Tope, M C., Wagner, P A., and Walch, M J.: The Earth Observing System Microwave Limb Sounder (EOS MLS) on the Aura Satellite, IEEE Trans. Geosci. Rem. Sens., 44, 1075–1092, \doi10.1109/TGRS.2006.873771, 2006.
Zhang, C., Mapes, B E., and Soden, B J.: Bimodality in tropical water vapour, Q. J. Roy. Meteor. Soc., 129, 2847–2866, \doi10.1256/qj.02.166, 2003.