| 61. |
- Stevens, M. H., et al.
(författare)
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Bright polar mesospheric clouds formed by main engine exhaust from the space shuttle's final launch
- 2012
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Ingår i: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 117:19, s. Art. no. D19206-
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Tidskriftsartikel (refereegranskat)abstract
- The space shuttle launched for the last time on 8 July 2011. As with most shuttle launches, the three main engines injected about 350 t of water vapor between 100 and 115 km off the east coast of the United States during its ascent to orbit. We follow the motion of this exhaust with a variety of satellite and ground-based data sets and find that (1) the shuttle water vapor plume spread out horizontally in all directions over a distance of 3000 to 4000 km in 18 h, (2) a portion of the plume reached northern Europe in 21 h to form polar mesospheric clouds (PMCs) that are brighter than over 99% of all PMCs observed in that region, and (3) the observed altitude dependence of the particle size is reversed with larger particles above smaller particles. We use a one- dimensional cloud formation model initialized with predictions of a plume diffusion model to simulate the unusually bright PMCs. We find that eddy mixing can move the plume water vapor down to the mesopause near 90 km where ice particles can form. If the eddy diffusion coefficient is 400 to 1000 m(2)/s, the predicted integrated cloud brightness is in agreement with both satellite and ground-based observations of the shuttle PMCs. The propellant mass of the shuttle is about 20% of that from all vehicles launched during the northern 2011 PMC season. We suggest that the brightest PMC population near 70 degrees N is formed by space traffic exhaust.
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| 62. |
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| 63. |
- Urban, Joachim, 1964, et al.
(författare)
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Odin/SMR Limb Observations of Nitric Acid in the Stratosphere
- 2007
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Ingår i: European Space Agency, (Special Publication) ESA SP. - 0379-6566. ; ESA-SP-636:SP-636
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The Sub-Millimetre Radiometer (SMR) on board the Odin satellite, launched in February 2001, observes thermal emissions of stratospheric nitric acid (HNO3) originating from the Earth limb in a band centred at 544.6GHz. The characteristics of the retrieved Odin/SMR version-2.0 HNO3 profiles are described. A climatology over more than five years of HNO 3 observations from 2001 to 2007 was created. Different aspects of the data, such as the global distribution and seasonal variation, the denitrification inside the polar vortices as well as the presence of high quantities of HNO3 in the middle and upper stratosphere at midwinter high latitudes are discussed.
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| 64. |
- Urban, Joachim, 1964, et al.
(författare)
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Odin/SMR Limb Observations of Stratospheric Trace Gases: Level 2 Processing of ClO, N2O, O3, and HNO3
- 2005
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Ingår i: Journal of Geophysical Research. - 0148-0227 .- 2156-2202. ; 110:D14, s. 1-20
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Tidskriftsartikel (refereegranskat)abstract
- The Sub-Millimetre Radiometer (SMR) on board the Odin satellite, launched on 20 February 2001, observes key species with respect to stratospheric chemistry and dynamics such as O-3, ClO, N2O, and HNO3 using two bands centered at 501.8 and 544.6 GHz. We present the adopted methodology for level 2 processing and the achieved in-orbit measurement capabilities of the SMR radiometer for these species in terms of altitude range, altitude resolution, and measurement precision. The characteristics of the relevant level 2 data versions, namely version 1.2 of the operational processor as well as versions 222 and 223 of the reference code, are discussed and differences are evaluated. An analysis of systematic retrieval errors, resulting from spectroscopic and instrumental uncertainties, is also presented.
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| 65. |
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| 66. |
- Urban, Joachim, 1964, et al.
(författare)
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Odin/SMR Observations of Stratospheric Water Vapour and its Isotopes: Requirements on Spectroscopy
- 2004
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Ingår i: Proc. Int. Workshop on Critical Evaluation of mm-/submm-wave Spectroscopic Data for Atmos. Observ., 29-30 January 2004, Mito, Japan, edited by Amano, T., Kasai, Y., Manabe, T.. ; , s. 69-74
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 67. |
- Wang, D.Y., et al.
(författare)
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Comparisons of MIPAS/ENVISAT ozone profiles with SMR/ODIN and HALOE/UARS observations
- 2005
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Ingår i: Advances in Space Research. - : Elsevier BV. - 1879-1948 .- 0273-1177. ; 36:5, s. 927-931
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Tidskriftsartikel (refereegranskat)abstract
- Ozone volume mixing ratio (VMR) profiles are measured by the Michelson Interferometer for passive atmospheric sounding (MIPAS) on ENVISAT. The data sets produced by the science data processor at Institut fur Meteorologic und Klimaforschung (IMK), Germany are compared with those obtained by halogen occultation experiment (HALOE) on UARS and by sub-millimetre radiometer (SMR) on ODIN. For the stratospheric measurements taken during September/October 2002, the three instruments show reasonable agreement, with global mean differences within 0.1-0.3 ppmv. The typical zonal mean differences are of 0.4 ppmv for HALOE and 0.6 ppmv for SMR (4-6%) in the ozone VMR peak region at 25-30 km near the equator, though larger differences of 0.8-1 ppmv (8-10%) are also observed in a small latitude-altitude region in the tropic. A positive bias of about 0.2-0.4 ppmv in the MIPAS data in the 35-40 km region has also been found. Further studies are under way to explain these differences.
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