TY - JOUR
T1 - Extending the satellite data record of tropospheric ozone profiles from Aura-TES to MetOp-IASI
T2 - Characterisation of optimal estimation retrievals
AU - Oetjen, H.
AU - Payne, V. H.
AU - Kulawik, S. S.
AU - Eldering, A.
AU - Worden, J.
AU - Edwards, D. P.
AU - Francis, G. L.
AU - Worden, H. M.
AU - Clerbaux, C.
AU - Hadji-Lazaro, J.
AU - Hurtmans, D.
N1 - Publisher Copyright:
© 2014 Author(s).
PY - 2014/12/8
Y1 - 2014/12/8
N2 - We apply the Tropospheric Emission Spectrometer (TES) ozone retrieval algorithm to Infrared Atmospheric Sounding Instrument (IASI) radiances and characterise the uncertainties and information content of the retrieved ozone profiles. This study focuses on mid-latitudes for the year 2008. We validate our results by comparing the IASI ozone profiles to ozone sondes. In the sonde comparisons, we find a negative bias (1-10%) in the IASI profiles in the lower to mid-troposphere and a positive bias (up to 14%) in the upper troposphere/lower stratosphere (UTLS) region. For the described cases, the degrees of freedom for signal are on average 3.2, 0.3, 0.8, and 0.9 for the columns 0 km - top of atmosphere, (0-6), (0-11), and (8-16) km, respectively. We find that our biases with respect to sondes and our degrees of freedom for signal for ozone are comparable to previously published results from other IASI ozone algorithms. In addition to evaluating biases, we validate the retrieval errors by comparing predicted errors to the sample covariance matrix of the IASI observations themselves. For the predicted versus empirical error comparison, we find that these errors are consistent and that the measurement noise and the interference of temperature and water vapour on the retrieval together mostly explain the empirically derived random errors. In general, the precision of the IASI ozone profiles is better than 20%.
AB - We apply the Tropospheric Emission Spectrometer (TES) ozone retrieval algorithm to Infrared Atmospheric Sounding Instrument (IASI) radiances and characterise the uncertainties and information content of the retrieved ozone profiles. This study focuses on mid-latitudes for the year 2008. We validate our results by comparing the IASI ozone profiles to ozone sondes. In the sonde comparisons, we find a negative bias (1-10%) in the IASI profiles in the lower to mid-troposphere and a positive bias (up to 14%) in the upper troposphere/lower stratosphere (UTLS) region. For the described cases, the degrees of freedom for signal are on average 3.2, 0.3, 0.8, and 0.9 for the columns 0 km - top of atmosphere, (0-6), (0-11), and (8-16) km, respectively. We find that our biases with respect to sondes and our degrees of freedom for signal for ozone are comparable to previously published results from other IASI ozone algorithms. In addition to evaluating biases, we validate the retrieval errors by comparing predicted errors to the sample covariance matrix of the IASI observations themselves. For the predicted versus empirical error comparison, we find that these errors are consistent and that the measurement noise and the interference of temperature and water vapour on the retrieval together mostly explain the empirically derived random errors. In general, the precision of the IASI ozone profiles is better than 20%.
UR - https://www.scopus.com/pages/publications/84915791193
U2 - 10.5194/amt-7-4223-2014
DO - 10.5194/amt-7-4223-2014
M3 - Article
AN - SCOPUS:84915791193
SN - 1867-1381
VL - 7
SP - 4223
EP - 4236
JO - Atmospheric Measurement Techniques
JF - Atmospheric Measurement Techniques
IS - 12
ER -