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ensemble filter algorithms. Section 4 applies these techniques to nonlinearly evolving shear instabilities. Finally, section 5 closes the manuscript with a recapitulation of the most important results and a discussion of the major conclusions. 2. Square root and perturbed observation ensemble generation We begin by reviewing the properties of square root and perturbed observation ensemble generation schemes. The presentation that follows only discusses the ensemble generation step of an ensemble
ensemble filter algorithms. Section 4 applies these techniques to nonlinearly evolving shear instabilities. Finally, section 5 closes the manuscript with a recapitulation of the most important results and a discussion of the major conclusions. 2. Square root and perturbed observation ensemble generation We begin by reviewing the properties of square root and perturbed observation ensemble generation schemes. The presentation that follows only discusses the ensemble generation step of an ensemble
Fast Playback Framework for Analysis of Ground-Based Doppler Radar Observations Using MapReduce Technologythe sizes of rainfall regions in landfalling TCs. Because of the scanning limitations of a single radar ( Carbone et al. 1985 ), multiradar composites are essential to many meteorological applications, including real-time weather forecasting, observational research of synoptic-scale weather systems, and numerical weather prediction models. This range of applications requires different data processing strategies. Real-time analysis requires a time-sensitive handling of input data from the recent
the sizes of rainfall regions in landfalling TCs. Because of the scanning limitations of a single radar ( Carbone et al. 1985 ), multiradar composites are essential to many meteorological applications, including real-time weather forecasting, observational research of synoptic-scale weather systems, and numerical weather prediction models. This range of applications requires different data processing strategies. Real-time analysis requires a time-sensitive handling of input data from the recent
Antenna Pattern Measurements of Weather Radars Using the Sun and a Point Source. Unfortunately, most cosmic sources with better characteristics than the sun (stable power, real point source) used in this community are too weak for weather radar observations. Nevertheless, some techniques developed in this area can be applied to weather radar measurements of the sun, too. In this paper, dedicated raster scans are used to derive the antenna pattern, exemplarily shown for the polarimetric Doppler weather radar POLDIRAD. The scan strategy and signal processing will be described in detail
. Unfortunately, most cosmic sources with better characteristics than the sun (stable power, real point source) used in this community are too weak for weather radar observations. Nevertheless, some techniques developed in this area can be applied to weather radar measurements of the sun, too. In this paper, dedicated raster scans are used to derive the antenna pattern, exemplarily shown for the polarimetric Doppler weather radar POLDIRAD. The scan strategy and signal processing will be described in detail
Identification and Reduction of Retracker-Related Noise in Altimeter-Derived Sea Surface Height Measurements). A variety of waveform models and parameter estimation algorithms have been employed for retracking that account for characteristics of the antenna, the scene illuminated by the radar pulse, and approximations to the physics of the ocean surface and its electromagnetic properties ( Rodriguez 1988 ; Zanifé et al. 2003 ; Thibaut et al. 2010 ). For the Jason-1 ( J1 ) and Jason-2 ( J2 ) missions, the GDR data values are obtained with a four-parameter maximum likelihood estimator retracker (MLE4
). A variety of waveform models and parameter estimation algorithms have been employed for retracking that account for characteristics of the antenna, the scene illuminated by the radar pulse, and approximations to the physics of the ocean surface and its electromagnetic properties ( Rodriguez 1988 ; Zanifé et al. 2003 ; Thibaut et al. 2010 ). For the Jason-1 ( J1 ) and Jason-2 ( J2 ) missions, the GDR data values are obtained with a four-parameter maximum likelihood estimator retracker (MLE4
) use data where ρ hv < 0.97 to identify the melting layer. For hail, ρ hv can be much lower because of Mie scattering. At present, quantitative use of ρ hv is hampered by a lack of rigorous confidence intervals accompanying the ρ hv estimates. Error estimates are available by adopting an empirical approach ( Illingworth and Caylor 1991 ) or a linear perturbation technique ( Liu et al. 1994 ; Torlaschi and Gingras 2003 ), both of which implicitly assume a Gaussian probability distribution
) use data where ρ hv < 0.97 to identify the melting layer. For hail, ρ hv can be much lower because of Mie scattering. At present, quantitative use of ρ hv is hampered by a lack of rigorous confidence intervals accompanying the ρ hv estimates. Error estimates are available by adopting an empirical approach ( Illingworth and Caylor 1991 ) or a linear perturbation technique ( Liu et al. 1994 ; Torlaschi and Gingras 2003 ), both of which implicitly assume a Gaussian probability distribution
organizational and operational paradigms. The separately funded ARM Unmanned Aerospace Vehicle (ARM-UAV) program carried out 12 missions between 1993 and 2006 relying on UAVs and piloted aircraft. The ARM-UAV program was established originally to develop measurement techniques and instruments suitable for use with a new class of high-altitude, long-endurance UAVs and to demonstrate these instruments and measurement techniques in a series of field campaigns designed to support the climate change community
organizational and operational paradigms. The separately funded ARM Unmanned Aerospace Vehicle (ARM-UAV) program carried out 12 missions between 1993 and 2006 relying on UAVs and piloted aircraft. The ARM-UAV program was established originally to develop measurement techniques and instruments suitable for use with a new class of high-altitude, long-endurance UAVs and to demonstrate these instruments and measurement techniques in a series of field campaigns designed to support the climate change community
A Point Cloud Method for Retrieval of High-Resolution 3D Gridded Reflectivity from Weather Radar Networks for Air Traffic Managementare combined using the DWM. The gridding technique known as objective analysis (OA) was developed originally to create analyses of meteorological variables for assimilation into NWP using irregularly spaced observation data, such as those provided by surface observing sites or by radiosonde ascents. The early schemes of Cressman (1959) and Barnes (1964) are probably the best known and have been used extensively for gridding of radar data (e.g., Henja and Michelson 1999 ). In addition to
are combined using the DWM. The gridding technique known as objective analysis (OA) was developed originally to create analyses of meteorological variables for assimilation into NWP using irregularly spaced observation data, such as those provided by surface observing sites or by radiosonde ascents. The early schemes of Cressman (1959) and Barnes (1964) are probably the best known and have been used extensively for gridding of radar data (e.g., Henja and Michelson 1999 ). In addition to
). Researchers have historically focused more on the precipitation retrieval algorithm development for imagers. For example, numerous algorithms, either using regression model or Bayesian technique, have been developed for the Special Sensor Microwave Imager (SSM/I) and Special Sensor Microwave Imager/Sounder (SSMIS; e.g., Spencer et al. 1989 ; Liu and Curry 1992 ; Petty 1994 ; Ferraro and Marks 1995 ; McCollum and Ferraro 2003 ; Sanò et al. 2013 ; You et al. 2015 ). Similarly, a variety of the
). Researchers have historically focused more on the precipitation retrieval algorithm development for imagers. For example, numerous algorithms, either using regression model or Bayesian technique, have been developed for the Special Sensor Microwave Imager (SSM/I) and Special Sensor Microwave Imager/Sounder (SSMIS; e.g., Spencer et al. 1989 ; Liu and Curry 1992 ; Petty 1994 ; Ferraro and Marks 1995 ; McCollum and Ferraro 2003 ; Sanò et al. 2013 ; You et al. 2015 ). Similarly, a variety of the
Radiometric Comparison of 1.6-μm CO2 Absorption Band of Greenhouse Gases Observing Satellite (GOSAT) TANSO-FTS with Suomi-NPP VIIRS SWIR BandCO 2 retrieval depends on a number of parameters, such as surface albedo, scattering albedo, surface pressure, aerosol optical thickness, and cloud-top height. These parameters can be estimated accurately from measurements only if the instrument is well calibrated in absolute scale. To meet the observation requirement for CO 2 retrieval, surface albedo and aerosol retrieval requires an accuracy of absolute radiometric calibration better than 5% ( Kuze et al. 2009a ). Several studies have been
CO 2 retrieval depends on a number of parameters, such as surface albedo, scattering albedo, surface pressure, aerosol optical thickness, and cloud-top height. These parameters can be estimated accurately from measurements only if the instrument is well calibrated in absolute scale. To meet the observation requirement for CO 2 retrieval, surface albedo and aerosol retrieval requires an accuracy of absolute radiometric calibration better than 5% ( Kuze et al. 2009a ). Several studies have been
1. Introduction Using a technique known as tomography , atmospheric temperature and wind vector profiles may be computed from sound speed observations. The technique has been widely used for many decades in oceanography, medicine, archaeology, and remote sensing of different geophysical media ( Brown et al. 2014 ; Kak and Slaney 2001 ). The first implementation of the technique to atmospheric observation was based on a series of 10-m towers that support microphones and loud speakers covering
1. Introduction Using a technique known as tomography , atmospheric temperature and wind vector profiles may be computed from sound speed observations. The technique has been widely used for many decades in oceanography, medicine, archaeology, and remote sensing of different geophysical media ( Brown et al. 2014 ; Kak and Slaney 2001 ). The first implementation of the technique to atmospheric observation was based on a series of 10-m towers that support microphones and loud speakers covering
