On the quality of MIPAS kinetic temperature in the middle atmosphere

The kinetic temperature and line of sight elevation information are retrieved from the MIPAS Middle Atmosphere (MA), Upper Atmosphere (UA) and NoctiLucent-Cloud (NLC) modes of high spectral resolution limb observations of the CO2 15 μm emission using the dedicated IMK/IAA retrieval algorithm, which considers non-local thermodynamic equilibrium conditions. These variables are accurately derived from about 20 km (MA) and 40 km (UA and NLC) to 105 km globally and both at daytime and nighttime. Typical temperature random errors are smaller than 0.5 K below 50 km, 0.5–2 K at 50–70 km, and 2–7 K above. The systematic error is typically 1 K below 70 km, 1–3 K from 70 to 85 km and 3–11 K from 85 to 100 km. The average vertical resolution is typically 4 km below 35 km, 3 km at 35–50 km, 4–6 km at 50–90 km, and 6–10 km above. We compared our MIPAS temperature retrievals from 2005 to 2009 with co-located ground-based measurements from the lidars located at the Table Mountain Facility and Mauna Loa Observatory, the SATI spectrograph in Granada (Spain) and the Davis station spectrometer, and satellite observations from ACE-FTS, Aura-MLS and TIMED-SABER from 20 km to 100 km. We also compared MIPAS temperatures with the high latitudes climatology from falling sphere measurements. The comparisons show very good agreement, with differences smaller than 3 K below 85–90 km in mid-latitudes. Differences over the poles in this altitude range are larger but can be generally explained in terms of known biases of the other instruments. The comparisons above 90 km worsen and MIPAS retrieved temperatures are always larger than other instrument measurements.MGC was supported by ESA within the framework of the Changing Earth Science Network Initiative. The IAA team was supported by the Spanish MICINN, under project AYA2008-03498/ESP, and EC FEDER funds

On the quality of MIPAS kinetic temperature in the middle atmosphere

The kinetic temperature and line of sight elevation information are retrieved from the MIPAS Middle Atmosphere (MA), Upper Atmosphere (UA) and NoctiLucent- Cloud (NLC) modes of high spectral resolution limb observations of the CO2 15 μm emission using the dedicated IMK/IAA retrieval algorithm, which considers non-local thermodynamic equilibrium conditions. These variables are accurately derived from about 20 km (MA) and 40 km (UA and NLC) to 105 km globally and both at daytime and nighttime. Typical temperature random errors are smaller than 0.5K below 50 km, 0.5–2K at 50–70 km, and 2–7K above. The systematic error is typically 1K below 70 km, 1–3K from 70 to 85 km and 3–11K from 85 to 100 km. The average vertical resolution is typically 4 km below 35 km, 3 km at 35–50 km, 4–6 km at 50–90 km, and 6–10 km above. We compared our MIPAS temperature retrievals from 2005 to 2009 with co-located ground-based measurements from the lidars located at the Table Mountain Facility and Mauna Loa Observatory, the SATI spectrograph in Granada (Spain) and the Davis station spectrometer, and satellite observations from ACE-FTS, Aura-MLS and TIMED-SABER from 20 km to 100 km. We also compared MIPAS temperatures with the high latitudes climatology from falling sphere measurements. The comparisons show very good agreement, with differences smaller than 3K below 85–90 km in midlatitudes. Differences over the poles in this altitude range are larger but can be generally explained in terms of known biases of the other instruments. The comparisons above 90 km worsen and MIPAS retrieved temperatures are always larger than other instrument measurements

Analysis of nonlocal thermodynamic equilibrium CO 4.7 m fundamental, isotopic, and hot band emissions measured by the Michelson Interferometer for Passive Atmospheric Sounding on Envisat

[1] Nonlocal thermodynamic equilibrium (non-LTE) simulations of the (CO)-C-12-O-16(1 -> 0) fundamental band, the (CO)-C-12-O-16(2 -> 1) hot band, and the isotopic (CO)-C-13-O-16(1 -> 0) band performed with the Generic Radiative Transfer and non-LTE population Algorithm (GRANADA) and the Karlsruhe Optimized and Precise Radiative Transfer Algorithm (KOPRA) have been compared to spectrally resolved 4.7 mu m radiances measured by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS). The performance of the non-LTE simulation has been assessed in terms of band radiance ratios in order to avoid a compensation of possible non-LTE model errors by retrieval errors in the CO abundances inferred from MIPAS data with the same non-LTE algorithms. The agreement with the measurements is within 5% for the fundamental band and within 10% for the hot band. Simulated (CO)-C-13-O-16 radiances agree with the measurements within the instrumental noise error. Solar reflectance at the surface or clouds has been identified as an important additional excitation mechanism for the CO( 2) state. The study represents a thorough validation of the non-LTE scheme used in the retrieval of CO abundances from MIPAS data

Intense Saharan Dust Outbreak over the Iberian Peninsula in springtime 2021: Monitoring and Characterization of Transported Dust Particles

In spring 2021 an intense Saharan dust outbreak reached the Iberian Peninsula (IP), lasting from 26 March until 5 April. It was monitored at six lidar stations, belonging to either MPLNET or ACTRIS/EARLINET networks, covering thus almost all the IP extension. Polarized Micro-Pulse Lidar measurements were carried out at El Arenosillo/Huelva (ARN, Spain; 37.1ºN, 6.7ºW, 40 m a.s.l.), Torrejón de Ardoz (TRJ, Spain; 40.5º N, 3.5º W, 568 m a.s.l, which is not within MPLNET yet), and Barcelona (BCN, Spain; 41.4ºN, 2.1ºE, 125 m a.s.l.); and multi-wavelength Raman lidars measurements were performed at Granada (GRA, Spain; 37.1ºN, 3.6ºW, 680 m a.s.l.), Évora (EVO, Portugal; 38.6ºN, 7.9º W, 293 m a.s.l.), and Madrid (MAD, Spain; 40.5ºN, 3.7ºW, 680 m a.s.l.). Both particle backscatter coefficient (βp) and particle linear depolarization ratio (δp) profiles are retrieved for all the stations under cloud-free conditions. The optical properties (backscatter and extinction coefficients at 532 nm) for both the fine (Df) and coarse (Dc) dust components are separately derived by applying the POLIPHON (POlarisation LIdar PHOtometer Networking; Mamouri and Ansmann, 2014) approach. Additionally, the mass concentration profiles, the mass extinction efficiency and the height of the centre-of-mass for both fine and coarse-modes are also calculated for the overall period. Results are compared along with the evolution of the dust intrusion as it crosses the IP