HNO3 concentrations are obtained from the IASI instrument and the data set is characterized for the first time in terms of vertical profiles, averaging kernels and error profiles. A validation is also conducted through a comparison with ground-based FTIR measurements, with good results. The data set is then used to analyse HNO3 spatial and temporal variability for the year 2011. The latitudinal gradient and the large seasonal variability in polar regions are well represented with IASI data.
G. Ronsmans, B. Langerock, C. Wespes, J. W. Hannigan, F. Hase, T. Kerzenmacher, E. Mahieu, M. Schneider, D. Smale, D. Hurtmans, M. De Mazière, C. Clerbaux, and P.-F. Coheur
Surface-based two-filter radon detectors monitor the ambient concentration of atmospheric radon-222, a natural tracer of mixing and transport. They are sensitive, but respond slowly to ambient changes in radon concentration. In this paper, a deconvolution method is used to successfully correct observations for the instrument response. Case studies demonstrate that it is beneficial, sometimes necessary, to account for the detector response, especially when studying near-surface mixing.
A. D. Griffiths, S. D. Chambers, A. G. Williams, and S. Werczynski
New radiosonde instruments for humidity-, radiation- and gas profile measurements were introduced in recent years, for atmospheric research and climate monitoring. Such instruments are intended to be reused on multiple flights. Here we introduce the return glider radiosonde (RGR), which enables flying and retrieving valuable in situ upper-air instruments. The RGR is lifted with weather balloons to a preset altitude, and a built-in autopilot flies the glider autonomously back to the launch site.
A. Kräuchi and R. Philipona
Using data from a new airborne Hyperspectral Thermal Emission Spectrometer (HyTES) instrument, we present a technique for the detection and wide-area mapping of emission plumes of methane and other atmospheric trace gas species over challenging and diverse environmental conditions with high spatial resolution, that permits direct attribution to sources in complex environments.
G. C. Hulley, R. M. Duren, F. M. Hopkins, S. J. Hook, N. Vance, P. Guillevic, W. R. Johnson, B. T. Eng, J. M. Mihaly, V. M. Jovanovic, S. L. Chazanoff, Z. K. Staniszewski, L. Kuai, J. Worden, C. Frankenberg, G. Rivera, A. D. Aubrey, C. E. Miller, N. K. Malakar, J. M. Sánchez Tomás, and K. T. Holmes
This paper is presenting a feasibility study focused on methods of estimating the turbulence intensity based on a class of navigational messages routinely broadcast by the commercial aircraft (known as ADS-B and Mode-S). Using this kind of information could have potentially significant impact on aviation safety. Three methods have been investigated.
J. M. Kopeć, K. Kwiatkowski, S. de Haan, and S. P. Malinowski
We validate 2-D ionospheric tomography reconstructions against EISCAT incoherent scatter radar measurements. The method is based on Bayesian statistical inversion. We employ ionosonde measurements for the choice of the prior distribution parameters and use a sparse matrix approximation for the computations. This results in a computationally efficient tomography algorithm with clear probabilistic interpretation. We find that ionosonde measurements improve the reconstruction significantly.
J. Norberg, I. I. Virtanen, L. Roininen, J. Vierinen, M. Orispää, K. Kauristie, and M. S. Lehtinen
We present the development of a new airborne mass spectrometer AIMS-H2O for the fast and accurate measurement of water vapor in the upper troposphere and lower stratosphere. The high accuracy needed for e.g. quantification of atmospheric water vapor transport processes or cloud formation is achieved by an in-flight calibration of the instrument. AIMS-H2O is deployed on the DLR research aircraft HALO and Falcon where it covers a range of water vapor mixing ratios from 1 to 500 ppmv.
S. Kaufmann, C. Voigt, T. Jurkat, T. Thornberry, D. W. Fahey, R.-S. Gao, R. Schlage, D. Schäuble, and M. Zöger
Seven gravity-wave-resolving instruments (satellites, radiosondes and a meteor radar) are used to compare gravity-wave energy and vertical wavelength over the Southern Andes hotspot. Several conclusions are drawn, including that limb sounders and the radar show strong positive correlations. Radiosondes and AIRS weakly anticorrelate with other instruments and we see strong correlations with local stratospheric winds. Short-timescale variability is larger than the seasonal cycle.
C. J. Wright, N. P. Hindley, A. C. Moss, and N. J. Mitchell
We describe an innovative instrument based on cavity ring-down spectroscopy that analyzes the stable isotopes of methane in the ambient atmosphere. This instrument was used to study atmospheric emissions from oil and gas extraction activities in the Uintah Basin in Utah. These measurements suggest that 85 ± 7% of the total emissions in the basin are from natural gas production. The easy field deployment of this instrument can enable similar regional attribution studies across the world.
C.W. Rella, J. Hoffnagle, Y. He, and S. Tajima
This paper describes the feasibility of using a differential absorption radar technique for the remote sensing of water vapor within clouds near the Earth surface from a spaceborne platform. The proposed methodology is shown to be theoretically achievable and complimentary to existing water vapor remote sensing methods.
M. D. Lebsock, K. Suzuki, L. F. Millan, and P. M. Kalmus
The CCA algorithm is applicable to any modern passive microwave radiometer on board polar orbiting satellites; it has been developed using a data set of co-located SSMIS and TRMM-PR measurements and AMSU-MHS and TRMM-PR measurements. The algorithm shows a small rate of false alarms and superior detection capability and can efficiently detect (POD between 0.55 and 0.71) minimum rain rate varying from 0.14 mm/h (AMSU over ocean) to 0.41 (SSMIS over coast).
D. Casella, G. Panegrossi, P. Sanò, L. Milani, M. Petracca, and S. Dietrich
This work presents a comprehensive study of SPN1 radiometers accuracy and sources of uncertainty, drawing on laboratory experiments, numerical modelling and comparison studies between measurements from this sensor and state-of-the art instruments for six diverse sites. Several clues are provided for improving the SPN1 accuracy and agreement with state-of-the art measurements.
J. Badosa, J. Wood, P. Blanc, C. N. Long, L. Vuilleumier, D. Demengel, and M. Haeffelin
The difference due to the content of a priori information between a constrained retrieval and the true atmospheric state is usually represented by a diagnostic quantity called smoothing error. In this paper it is shown that the concept of the smoothing error as a component of the retrieval error budget is questionable because it is not compliant with Gaussian error propagation.
T. von Clarmann