Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna Chiara Piccolo and Anu Dudhia Precision Validation

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna Random error mapping of the radiometric noise on the retrieved profiles proportional to NESR and inverse proportional to temperature (it does not directly depend on VMR profiles) pT error propagation contribution –does not depend on target species profile –included in the error budget Pressure registration error –due to lack of knowledge of the pressure at the tangent altitude although the pointing is known –depends on the target species profile –very small: not included in the error budget

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna H2O RND time series

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna HNO3 RND time series

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna Variability of RND with time is evident for both species in the polar latitude bands –peak in polar winter cases –smaller intensity in Northern Hemisphere –second peak in Feb04 (Northern polar bands) –no variation at mid&equatorial latitudes All other species present similar behaviour Are these variations due to temperature? –Does the NESR vary with time?  Jul-Aug02 and Oct02: missing Antarctic L2 data RND time series

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna NESR time series Jul-Aug02 and Oct02: Missing Antarctic L2 profiles Sep03: missing Antarctic NESR data

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna Temperature time series

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna NESR slightly depends on the variation of the signal with time through the variation of atmospheric temperature Temperature variations with time explain quite well RND variations in both hemisphere –the increase of RND error at polar winters corresponds to the decrease of temperature –double peaks in northern polar winters correspond to double deeps in temperature –low (~150K) Temperature Oct02 for 20S-EQU?  September 03: missing Antarctic NESR data? NESR & T time series

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna Precision: dispersion of an ensemble of retrievals of the same atmospheric state Approximation: pairs of measurements located at the intersections of MIPAS viewing tracks Standard deviation of the ensemble of the profile pairs is a combination of the random uncertainties and the variability of the atmosphere Comparison between matching profile pairs and predicted random error given by MIPAS Offline L2 data (but NO 2 since large diurnal difference at intersections) Matching criteria: 300km for every 5 days per month –within 6h: matches near the poles only –within 12h: matches at three additional latitudes Validation methodology

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna Matches locations

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna Matches at 80N-90N

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna Time series of the ratio of the statistic of observed scatter over the predicted random error (with and without pT error contribution included) for the four latitude bands: (90S-80S, 80S-60S, 60N-80N, 80N-90N)  TEM follows seasonal variability  H2O, O3 and N2O: big oscillations that could be caused by oscillating matched profiles (time series different one day to the next)  HNO3 and CH4: SD of the matching pairs ensemble reasonable explained by predicted random error when pT error contribution included Validation Results

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna Only RND error

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna RND + pT error

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna TEM RND time series

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna O3 RND time series

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna CH4 RND time series

Atmospheric, Oceanic & Planetary Physics, University of Oxford QWG-11, October 2006, Bologna N2O RND time series