Ground-based validation of altitude, temperature, and four primary trace gas products of the operational MIPAS Level-2 processor

Transcription

1 Ground-based validation of altitude, temperature, and four primary trace gas products of the operational MIPAS Level-2 processor D. Hubert 1, A. Keppens 1, J. Granville 1, T. Verhoelst 1, J.-C. Lambert 1, P. Raspollini 2, A. Dehn 3 1 Royal Belgian Institute for Space Aeronomy (BIRA-IASB), 2 Istituto di Fisica Applicata "Nello Carrara" (IFAC-CNR), 3 ESA-ESRIN

2 MIPAS operational processor A brief history of Level-2 IPF V4 ( ) IPF V5 (5.02, 5.05, 5.06) IPF V7 (7.11) IPF V8 (8.X) Modifications in V7 processors Level-1b inflight non-linearity correction, altitude determination, spike detection/correction, Level-2 five more trace gas products, better microwindows FR, new approach continuum retrieval, IVS regularisation, More at ACVE 2016 V7: talk by Wetzel (MIPAS-B), and posters by Raspollini (ML2PP/ORM) & Laeng (IMK-IAA) V8: talk by Perron (L1b), and posters by Raspollini, Piro & Sgheri (ML2PP/ORM)

3 Ground-based validation GAW-contributing networks NDACC, SHADOZ, o radio/ozonesonde (85) stratospheric O3 lidar (12) + T lidar (9) FTIR (10-13) O3 MWR (2)

4 More at talks on QA/val. system (Keppens), co-location mismatch (Verhoelst), homogeneity O3sonde network (Hubert) ACVE posters on SCIAMACHY SGP V6 (Keppens), metrological best practices (Compernolle) ACVE workshop 2016

5 Temperature V7 cooler for & warmer in tropical UTLS radiosonde T lidar

6 Temperature Drift changes by K / decade Only OR period considered Linear regression model Weighted average over station sample Preliminary drift + 95% CI 90N-90S N-90S

7 MIPAS corrected altitude Radiosonde Altitude Previous scale has clear limitations 3-month moving median ± IP68% MIPAS: V5 V6 V7 110 hpa (15 km) 50.1 hpa (20 km) 22.6 hpa (25 km) 10.2 hpa (30 km) 60N-90N 30N-60N 30N-30S 30S-60S 60S-90S

8 MIPAS ECMWF corrected altitude Radiosonde ACVE workshop 2016 Altitude but the new ECMWF-anchored scale is superior (by far) 3-month moving median ± IP68% MIPAS: V5 V6 V7 110 hpa (15 km) 50.1 hpa (20 km) 22.6 hpa (25 km) 10.2 hpa (30 km) 60N-90N 30N-60N 30N-30S 30S-60S 60S-90S

9 Ozone FR: ~5% changes in UT/LS; OR: 1-2% increase O3 sonde O3 lidar

10 Ozone Drift changes by 1 3% / decade Only OR period considered Linear regression model Weighted average over station sample Drift + 95% CI 90N-90S N-90S

11 MIPAS vs NDACC FTIR CH 4 FR: reduced bias; OR: increase by ~5% MIPAS 1σ SYST, DAY 76.5 N 67.8 N 47.4 N 46.5 N 43.8 N 28.3 N

12 N 2 O FR: reduced bias; OR: increase by ~5% MIPAS vs NDACC FTIR MIPAS 1σ SYST, DAY 76.5 N 67.8 N 47.4 N 46.5 N 43.8 N 28.3 N

13 MIPAS vs NDACC FTIR HNO 3 No clear changes MIPAS 1σ SYST, DAY 80.0 N 78.9 N 76.5 N 67.8 N 46.5 N 28.3 N

14 Change V7 (vs. V6) Maturity ACVE workshop 2016 Conclusions ML2PP 7.03 released & characterised versus ground networks Altitude Temperature O3 CH4 HNO3 N2O V7 MIPAS corrected altitude better in FR, worse in OR ECMWF corrected altitude superior to MIPAS corrected altitude (no bias, no drift) FR: increased negative bias OR: similar bias, but positive drift V7-V6 OR: V7-GND more stable in US, less stable in MS+LS V7 overall quite similar to V5/V6 FR : V7 bias smaller in UT/LS OR : V7 bias larger between 5-50hPa No clear signs of additional drift ~5 % bias (slightly more pos. than V6) W.r.t. V6 smaller bias for FR Vert. bias dep. within spread ~5 % spread ~ -5 %/d drift insignificant Bias from -20 to 30 % (~ V6) Strong vertical dependence More neg. bias in local winter Up to 50 % spread No significant drifts ~5 % bias (slightly more pos. than V6) W.r.t. V6 smaller bias for FR Vert. bias dep. within spread ~5 % spread ~ -5 %/d drift insignificant Consistent picture sonde and GPS RO Picture qualitatively consistent sonde, lidar, GPS RO and MIPAS-B Consistent picture sonde, lidar and MIPAS-B More consistent picture than for V6 comparisons Difficult intercomparison due to large spreads Rather consistent picture Full details (of this analysis) in Technical Note ML2PP7-Iss1-RevB

15 More information Detailed validation reports Available at (Envisat > MIPAS > Cal/Val > Validation Activities)

16 More information ESA SPPA website

17 More information Product Quality Readme File Available at (Envisat > MIPAS > Products & Algorithms > Products Information)