Validation of temperature retrievals obtained by the Limb Infrared Monitor of the Stratosphere (LIMS) Experiment on NIMBUS 7

The LIMS is a six-channel limb scanning infrared radiometer flying on the NIMBUS 7 spacecraft. It measured radiances from October 25, 1978 to May 28, 1979, from which vertical profiles of temperature, ozone, water vapor, nitric acid and nitrogen dioxide were derived. The temperature is of major importance for studies of middle atmospheric dynamics, as well as for chemical and radiative studies. It is also needed by LIMS in order to derive the concentrations of the trace gases. This paper briefly outlines the temperature determination (as a function of pressure) from measurements in two channels covering portions of the 15-μm band of CO2. The known sources of error, from the radiometer and data reduction, are used to estimate the systematic and random errors (accuracy and precision, respectively) expected of the results. Observational determinations of the complete end-to-end precision are obtained by computing the standard deviation of six sequential temperature retrievals in regions where the atmosphere is horizontally uniform. This yields values of 0.2 to 0.6 K, in reasonable agreement with the estimates. A correction for horizontal gradients in the atmosphere leads to a large reduction in the differences between the stratospheric temperatures determined on the ascending and descending portions of the orbit. The temperatures agree in the mean with radiosondes and rocketsondes to within 1–2 K in most regions below 1 mbar. This is approximately the accuracy of these in situ sensors in the stratosphere. Above 1 mbar, LIMS temperatures are cooler than rocketsondes by a few degrees at all latitudes, especially in mid-latitude winter. However, comparisons with other results suggest that rocket temperatures are high, contributing at least part of the error. The temperature cross sections show several interesting features, such as cold regions in the mid-latitude mesosphere and wavelike vertical variations in the tropics, which have not been seen before. These data provide a useful and in some ways unique basis for studies of the stratosphere and mesosphere.

[1]  John C. Gille,et al.  The Limb Infrared Monitor of the Stratosphere: Experiment Description, Performance, and Results , 1984 .

[2]  John C. Gille,et al.  Accuracy and precision of the nitric acid concentrations determined by the limb infrared monitor of the stratosphere experiment on NIMBUS 7 , 1984 .

[3]  S. R. Drayson,et al.  Validation of nitrogen dioxide results measured by the Limb Infrared Monitor of the Stratosphere (LIMS) Experiment on NIMBUS 7 , 1984 .

[4]  J. Russell,et al.  The validation of NIMBUS 7 LIMS measurements of ozone , 1984 .

[5]  John C. Gille,et al.  Validation of water vapor results measured by the Limb Infrared Monitor of the Stratosphere Experiment on NIMBUS 7 , 1984 .

[6]  John J. Barnett,et al.  Temperature comparisons between the NIMBUS 7 SAMS, rocket/radiosondes and the NOAA 6 SSU , 1984 .

[7]  S. R. Drayson,et al.  Spectroscopy and transmittances for the LIMS Experiment , 1984 .

[8]  J. Gille,et al.  Evidence for Equatorial Kelvin Modes in Nimbus-7 LIMS , 1984 .

[9]  J. Gille,et al.  Infrared limb scanning in the presence of horizontal temperature gradients: an operational approach. , 1982, Applied optics.

[10]  J. Olivero,et al.  Can the standard radiosonde system meet special atmospheric research needs , 1982 .

[11]  P. D. Phillips,et al.  Reproducibility of VIZ Radiosonde Data and Some Sources of Error. , 1981 .

[12]  J. Barnett,et al.  Review of the radiance distribution in the upper mesosphere as observed from the Nimbus 6 Pressure Modulator Radiometer (PMR) , 1981 .

[13]  F. Schmidlin.  Repeatability and measurement uncertainty of the united states Meteorological Rocketsonde , 1981 .

[14]  L. Gordley,et al.  Rapid inversion of limb radiance data using an emissivity growth approximation. , 1981, Applied optics.

[15]  W. Planet,et al.  Intensities and pressure-broadened widths of CO2 R-branch lines at 15 μm from tunable laser measurements , 1980 .

[16]  J. Gille,et al.  Sounding the Stratosphere and Mesosphere by Infrared Limb Scanning from Space , 1980, Science.

[17]  J. Gille,et al.  Temperature and composition measurements from the l.r.i.r. and l.i.m.s. experiments on Nimbus 6 and 7 , 1980, Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences.

[18]  J. Russell,et al.  Limb Infrared Monitor of the Stratosphere (LIMS) experiment , 1978 .

[19]  J. Susskind,et al.  Synthetic atmospheric transmittance spectra near 15 and 4.3 microns , 1978 .

[20]  S. R. Drayson,et al.  The inference of atmospheric ozone using satellite horizon measurements in the 1042 per cm band. , 1972 .

[21]  John C. Gille,et al.  On the inversion of limb radiance measurements. I. , 1971 .

[22]  O. White,et al.  The Analysis and Restoration of Astronomical Data via the Fast Fourier Transform , 1971 .

[23]  J. J. Lambiotte,et al.  A technique to infer atmospheric temperature from horizon radiance profiles , 1969 .

[24]  D. Wark.  Validation of satellite-derived atmospheric temperature and water vapor concentration using radiosonde and rocketsonde measurements , 1983 .

[25]  J. L. Brownscombe,et al.  Validation of the stratospheric sounding unit , 1983 .

[26]  P. Conti.  IUE observations of hot stars , 1983 .

[27]  J. Russell,et al.  Results from the LIMS experiment for the PMP-1 winter 1978/79 , 1982 .

[28]  K. Hurley.  Gamma-ray bursts — the current status , 1982 .