X. Zou

• Professor at Nanjing University of Information Science and Technology

Higher cloud top and stronger convection within Typhoon Lekima (2019) corresponds to lower brightness temperature (TB) from Fengyun‐4A (FY‐4A) Advanced Geostationary Radiation Imager (AGRI) observations. In this study, an effort is made to see if all‐sky TB simulations from short‐term model forecasts by a radiative transfer model could capture obse...

The Cross‐track Infrared Sounder (CrIS) observations (O) contributed greatly to numerical weather prediction. Further contribution depends on the success of all‐sky data assimilation, which requires a method to produce realistic cloud/rain band structures from background fields (i.e., 6‐hr forecasts), and to remove large biases of all‐sky simulatio...

The use of remote sensing methods to accurately measure cloud properties and their spatiotemporal changes has been widely welcomed in many fields of atmospheric research. The Nanjing Joint Institute for Atmospheric Sciences (NJIAS) Himawari-8/9 Cloud Feature Dataset (HCFD) provides a comprehensive description of cloud features over the East Asia an...

GOES-16 Advanced Baseline Imager (ABI) observations of brightness temperature (TB) are used to examine the temporal evolutions of convection-affected structures of Hurricane Irma (2017) during its rapid intensification (RI) period from 0600 to 1800 UTC 4 September 2017. The ABI observations reveal that both an elliptical eye and a spiral rainband t...

Reanalysis data are extensively employed in investigation of the tropical large-scale climate variability. In this study, we attempt to use the Advanced Microwave Sounding unit-A (AMSU-A) window channel brightness temperature (TB) observations to examine their relationship with the sea surface temperature (SST). A close relationship is found betwee...

All‐sky simulations of brightness temperature (TB) at Microwave Humidity Sounder‐2 (MWHS‐2) channel 15 from Fengyun‐3E (FY‐3E) are generated based on the European Center for Medium‐Range Weather Forecasts (ECMWF) reanalysis version 5 (ERA5) and the National Centers for Environmental Prediction (NCEP) Global Forecast System (GFS) analysis for four t...

Microwave observations of brightness temperature (TB) from multiple polar‐orbiting operational environmental satellite imagers and infrared observations of geostationary operational environmental satellite Himawari‐8 imager are used to investigate characteristic features of secondary eyewall evolution of Typhoon Lekima (2019). It is found that micr...

In this study, a new way to assimilate clear-sky Advanced Himawari Imager (AHI) surface-sensitive brightness temperature (TB) observations over land is investigated for improving quantitative precipitation forecasts (QPFs) in eastern China. To alleviate problems arising from inaccurate surface temperature in radiance simulations, surface-station ob...

The use of remote sensing method to accurately measure cloud properties and their spatiotemporal changes has been widely welcomed in many fields of atmospheric research. The Nanjing Joint Institute for Atmospheric Sciences (NJIAS) Himawari-8/9 Cloud Feature Dataset (HCFD) provides a comprehensive description of cloud features over the East Asia and...

Influences of cloud liquid water, cloud ice, rain, snow, and graupel on all-sky simulations of the Cross-track Infrared Sounder (CrIS) brightness temperature (TB) are assessed for the 399 data assimilation (DA) channels. The analyses generated by the Gridpoint Statistical Interpolation (GSI) 3D-Var system assimilating conventional and clear-sky sat...

The newly launched early-morning satellite Fengyun-3E (FY-3E) helps to form a three-orbit constellation for better observing the first typhoon Malakas in 2022. Together with MetOp-B and NOAA-20, global observations are made available six times daily from three temperature sounders of MWTS-3, AMSU-A, and ATMS onboard FY-3E, MetOp-B, and NOAA-20, res...

Brightness temperature (TB) observations at an infrared channel (10.3 μm) of the Advanced Baseline Imager (ABI) on board the U. S. 16th Geostationary Operational Environmental Satellite (GOES-16) are used for determining tropical cyclone (TC) center positions and rainband sizes. Firstly, an azimuthal spectral analysis method is employed to obtain a...

The Formosa Satellite-7/Constellation Observing System for Meteorology, Ionosphere, and Climate-2 (Satellite-7/COSMIC-2), which was successfully launched on 25 June 2019, provides dense radio occultation (RO) observations over the tropics and subtropics. This study examines the RO-observed lowest altitude and its possible relationship to refractivi...

The northeast China cold vortex (NCCV) refers to a closed low‐pressure system over northeast China extending from China‐Siberia to the northwest Pacific coast region. It is cut off from the westerly jet belt in the middle and upper troposphere, has a cold core, lasts several days, and could bring heavy rain events in late spring and summer that are...

Global positioning satellite system (GPS) radio waves that reach the tropical lower troposphere are strongly affected by small-scale water vapor fluctuations. We examine along-the-ray simulations of the impact parameter at every ray integration step using the high-resolution European Centre for Medium-Range Weather Forecasts ERA5 reanalysis as the...

In this study, the three-dimensional (3D) warm-core structures of the Northwest Pacific typhoons Francisco, Lekima, and Krosa in August 2019 are retrieved from the Fengyun-3D (FY-3D) microwave temperature sounder-2 (MWTS-2) observations of brightness temperature. Due to the lack of two window channels at 23.8 GHz and 31.4 GHz, an empirical cloud de...

Atmospheric refractivity fields are more strongly affected by more water vapor in the tropical lower troposphere than elsewhere. In this study, based on model simulations, we first collocated the radio occultation (RO) data in 2009 from the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) with CloudSat cloud profilin...

Microwave temperature sounding observations from polar-orbiting meteorological satellites have been widely used for research on climate trends of atmospheric temperature at different heights around the world. Taking the Amazon rainforest as the target area, this study combined the Microwave Temperature Sounder-2 (MWTS-2) data onboard the Chinese Fe...

Cloud optical/microphysical properties (COMP) with a high spatiotemporal resolution are required for monitoring the evolution of convective clouds, studying aerosol–cloud–precipitation interactions, and evaluating cloud microphysics parameterization schemes in weather and climate models. This study applied the bispectral method, commonly used for C...

Hurricane top structures are not well captured by airborne or dropsonde observations. Total column ozone (TCO) observations provided by the Ozone Mapping and Profiler Suite (OMPS) Nadir Mapper (NM) onboard the Suomi National Polar-orbiting Partnership (S-NPP) satellite are employed in an investigation of hurricane top structures. We show that the O...

Satellite observations of brightness temperature from the Advanced Technology Microwave Sounder (ATMS) and Microwave Humidity Sounder (MHS) humidity sounding channels can provide relatively high horizontal resolution information about cloud and atmospheric moisture in the troposphere, thus revealing the structures of tropical cyclones (TCs). There...

A four-dimensional variational (4D-Var) data assimilation (DA) system is developed for the global nonhydrostatic atmospheric dynamical core of the Model for Prediction Across Scales (MPAS). The nonlinear forward and adjoint models of the MPAS-Atmosphere dynamic core are included in a Python-driven structure to formulate a continuous 4D-Var DA syste...

Measurements from various sounding instruments onboard polar-orbiting meteorological satellites quantify contributions to the total radiation at various microwave or infrared frequencies from different levels of the atmosphere. Satellite data assimilation adjusts model profiles of temperature and water vapor by minimizing the differences between ob...

The cloud-top-phase climatology over the western North Pacific (WNP) has received little attention. Using 3 years (2017–2019) of cloud-top-phase products from the Advanced Himawari Imager onboard the Japanese Himawari-8 satellite, this study examines the seasonal and diurnal variations in the cloud-top phase over the WNP. Results show that over the...

Aimed at improving all-sky Cross-track Infrared Sounder (CrIS) radiance assimilation, this study explores the benefits for CrIS all-sky radiance simulations, focusing on the accuracy of background cloud information, through assimilating cloud liquid water path (LWP), ice water path (IWP), and rain water path (RWP) data retrieved from the Advanced T...

With the rapid advances and abundant observations from Chinese Fengyun-3 (FY-3) meteorological satellites, it is of great interest to summarize a decade of quality assessments of FY-3 observations. The topics covered are noise characterization, bias estimation, striping noise detection and mitigation of striping noise, radio frequency interference...

Developed here is an algorithm for determining the infrared (IR) cloud-top phase for advanced Himawari imager (AHI) measurements from the Japanese geostationary satellite Himawari-8. The tests and decision tree used in the AHI algorithm are different from those in the Moderate Resolution Imaging Spectroradiometer (MODIS) Level-2 cloud product algor...

Global Positioning System (GPS) radio occultation (RO) and radiosonde (RS) observations are two major types of observations assimilated in numerical weather prediction (NWP) systems. Observation error variances are required input that determines the weightings given to observations in data assimilation. This study estimates the error variances of g...

The Hyperspectral Infrared Atmospheric Sounder (HIRAS) onboard the Feng Yun-3D (FY-3D) satellite is the first Chinese hyperspectral infrared instrument. In this study, an improved cloud detection scheme using brightness temperature observations from paired HIRAS long-wave infrared (LWIR) and short-wave infrared (SWIR) channels at CO2 absorption ban...

Observation error variances are required input parameters for assimilating GPS radio occultation (RO) data in numerical weather prediction systems. A three‐cornered hat method is applied to estimate RO observation error standard deviation (SD) of both refractivity and bending angle. RO data from the Global Navigation Satellite System Receiver for A...

Determining tropical cyclone (TC) center positions is of interest to many researchers who conduct TC analysis and forecasts. In this study, we develop and apply a TC centering technique to CrIS and ATMS observations of brightness temperature and report on an improvement of accuracy by adding a TC spectral analysis to the state of the art (ARCHER),...

In the tropical lower troposphere, the radio occultation (RO) bending angle can have complex and sharp structures. In current numerical weather prediction data assimilation, the estimated observation uncertainty (or error) of the RO bending angle is typically derived from a fixed‐fraction uncertainty model of the RO bending angle. Therefore, the co...

This study develops and tests a version of the Python-driven, non-hydrostatic Model for Prediction Across Scales – Atmosphere (MPAS-A) dynamic model, as well as its tangent linear and adjoint models. The non-linear, non-hydrostatic dynamic core of the MPAS-A is restructured to have a Python driver for the convenience of parsing namelists, manipulat...

The Advanced Microwave Sounding Unit (AMSU)-A/Advanced Technology Microwave Sounder (ATMS) onboard the National Oceanic Atmospheric Administration (NOAA)-18/-19, MetOp-A/-B, and Suomi National Polar-orbiting Partnership satellites provide global observations of the cloud Liquid Water Path (LWP) almost 10 times a day. This study explores the possibi...

This study explores the possibility of improving the impact of the Advanced Himawari Imager (AHI) clear‐sky radiance data assimilation (DA), focusing on cloud detection. First, the performance of the “clear‐channel” detection scheme of the minimum residual (MR) method embedded in the Gridpoint Statistical Interpolation (GSI) DA system is compared w...

The Fengyun (FY)-3C/D microwave temperature sounder-2 (MWTS-2) is similar to the Advanced Microwave Sounding Unit-A (AMSU-A), except it lacks two window channels located at 23.8 GHz and 31.4 GHz. This makes a clear-sky data determination challenging for the MWTS-2 due to the unavailability of cloud liquid water path (LWP) retrievable from the two w...

Satellite microwave temperature sounding data have been widely used in the study of climate trends over the past decades. When merging advanced microwave sounding unit-A (AMSU-A) data from 1998 to 2017 from different satellites, brightness temperature observations can be affected by differences in the center frequency, incidence angle, and local eq...

Both the Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) Data Analysis and Archival Center (CDAAC) and the European Radio Occultation Meteorology Satellite Application Facility (ROM) process the radio occultation data from the Global Navigation Satellite System Receiver for Atmospheric Sounding (GRAS) onboard the Me...

The second Advanced Technology Microwave Sounder (ATMS) was onboard the National Oceanic and Atmospheric Administration (NOAA)-20 satellite when launched on 18 November 2017. Using nearly six months of the earliest NOAA-20 observations, the biases of the ATMS instrument were compared between NOAA-20 and the Suomi National Polar-Orbiting Partnership...

Satellite data assimilation of hyperspectral Cross-track Infrared Sounder (CrIS) clear channels in regions with but not affected by low-level clouds requires a set of height-dependent cloud emission and scattering indices (CESIs) that are sensitive to cloud top pressures. In this study, three CESIs are generated by pairing CrIS longwave and shortwa...

Microwave temperature sounders (MWTS) onboard Polar-orbiting Operational Environmental Satellites (POES) provide measurements in the microwave spectrum around 60 GHz. The amount of thermal emission measured at different frequencies depends mainly on the atmospheric temperature at different altitudes. Measurements from MWTS were among the earliest t...

Observations can be directly assimilated in a three-dimensional variational (3D-Var) system as long as there is a forward model to generate simulations from a given model state. Dynamic and mathematical smoothing constraints can be either directly built into 3D-Var systems or added as penalty terms while assimilating newly available observations du...

The Microwave Radiation Imager (MWRI) on board the FengYun‐3 (FY‐3) series of satellites can provide global observations four times daily, which significantly improves the ability to monitor large‐scale natural disasters. There is noticeable striping noise in brightness temperature observations from the MWRIs on board the FY‐3B, FY‐3C and FY‐3D sat...

The Tibetan Plateau (TP) and the atmospheric conditions over it strongly affect downstream regional weather. Advanced Microwave Sounding Unit-A (AMSU-A) brightness temperature observations provide temperature sounding information and have been long assimilated successfully for numerical weather prediction. AMSU-A brightness temperatures observed fr...

A four-dimensional variational (4D-Var) vortex initialization (VI) system is developed for a nonhydrostatic axisymmetric numerical model with convection accounted for (the RE87 model). Derivations of the tangent linear and adjoint models of the RE87 model and the correctness checks are presented. As an initial evaluation of the 4D-Var VI system, a...

The Microwave Temperature Sounder (MWTS)-2 has a total of 13 temperature-sounding channels with the capability of observing radiance emissions from near the surface to the stratosphere. Similar to the Advanced Technology Microwave Sounder (ATMS), striping pattern noise, primarily in the cross-track direction, exists in MWTS-2 radiance observations....

Global observations from the Advanced Technology Microwave Sounder (ATMS) onboard the Suomi National Polar-Orbiting Partnership satellite are affected by striping-patterned noise. An optimal symmetric filter method to mitigate the striping noise in warm counts, cold counts, warm load temperatures, and scene counts instead of antenna temperatures is...

The relationship between differences in microwave humidity sounder (MHS)–channel biases which represent measured brightness temperatures and model-simulated brightness temperatures, and cloud ice water path (IWP) as well as the influence of the cloud liquid water path (LWP) on the relationship is examined. Seven years (2011–17) of NOAA-18 MHS-deriv...

The Advanced Technology Microwave Sounder (ATMS) onboard the Suomi National Polar-Orbiting Partnership satellite is a cross-track scanning instrument containing 22 sounding channels in total. In this study, the bias characteristics of channels 1–6, which could have significant cloud contamination in heavy precipitation, are first analyzed based on...

In the moist tropical lower troposphere, atmospheric refractivity fields are strongly affected by water vapour and have complicated, non‐spherically symmetric structures. Strong horizontal gradients of refractivity could make the simulated bending angle by raytracing a multivalued function of the impact parameter, which is called impact multipath f...

The Advanced Technology Microwave Sounder (ATMS) is onboard both the National Oceanic and Atmospheric Administration (NOAA)-20 and the Suomi National Polar-Orbiting Partnership (S-NPP) satellites. NOAA-20 has the same sun-synchronous orbit as that of the S-NPP, but is 50 min (i.e., half orbit) ahead. The striping noise is found in ATMS brightness t...

Observations from the microwave sounding unit (MSU), from 1978 to 2006 and its successor, the Advanced Microwave Sounding Unit-A (AMSU-A, 1998–present), and onboard the National Oceanic and Atmospheric Administration’s polar-orbiting satellites have been widely used for estimating global climate trends. The MSU has a long-term data set, but it is d...

Bias correction (BC) is a crucial step for satellite radiance data assimilation (DA). In this study, the traditional airmass BC scheme in the National Centers for Environmental Prediction (NCEP) Gridpoint Statistical Interpolation (GSI) is investigated for Cross-track Infrared Sounder (CrIS) DA. The ability of the airmass predictors to model CrIS b...

The algorithm to retrieve the ice water path (IWP) from Microwave Humidity Sounder (MHS) measurements of two window channels at 89 and 157 GHz was already developed, and the IWP retrieval products have been made operationally available since NOAA-15. An adaptation of the same algorithm to the Advanced Technology Microwave Sounder (ATMS) is not stra...

The FORMOSAT-7/Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC-2) will provide more radio occultation (RO) data in the tropical lower troposphere than ever before. Accurate observation operators are important to fully realize the benefits of COSMIC-2 data for high-resolution numerical weather prediction through data...

The conical-scanning Tropical Rainfall Measuring Mission Microwave Imager (TMI), which plays an important role in monitoring global precipitation, has nine channels. A clear striping noise feature is found in pitch-over maneuver data of deep-space and earth-view observations at all nine channels of the TMI. A modified striping noise mitigation algo...

Due to a shorter effective integration time for each field‐of‐view (FOV) of the Advanced Microwave Temperature Sounder (ATMS) onboard the Suomi National Polar‐orbiting Partnership (S‐NPP) satellite than that for the Advanced Microwave Sounding Unit‐A (AMSU‐A) onboard previous National Oceanic and Atmospheric Administration (NOAA) polar‐orbiting sat...

The final published version of this manuscript will replace the preliminary version. If you would like to cite this EOR in a separate work, please use the following full citation: Tian, X., X. Zou, and S. Yang, 2018: A limb correction method for the Microwave Temperature Sounder 2 and its applications. Adv. Atmos. Sci., 35, https://doi. ABSTRACT Th...

Tropical cyclone (TC) temperature and water vapor structures are essential atmospheric variables. In this study, global positioning system (GPS) radio occultation (RO) observations from the GPS RO mission named the Constellation Observing System for Meteorology, Ionosphere, and Climate and the Global Navigation Satellite System (GNSS) Receiver for...

Convective initiation (CI) nowcasting often has a low probability of detection (POD) and a high false-alarm ratio (FAR) at sub-tropical regions where the warm-rain processes often occur. Using the high spatial- and temporal-resolution and multi-spectral data from the Advanced Himawari Imager (AHI) on board Japanese new-generation geostationary sate...

The fluctuation of radio occultation (RO) signals in the presence of refractivity irregularities in the moist lower troposphere results in uncertainties of retrieved bending angle and refractivity profiles. In this study the local spectral width (LSW) of ROsignals, transformed to impact parameter representation, is used for the characterization of...

MicroWave Radiation Imagers (MWRIs) onboard the afternoon FengYun-3B (FY-3B) and midmorning FengYun-3C (FY-3C) satellites provide global observations almost 4 times a day at any location. This study examines the diurnal cycle of the liquid water path (LWP) over the southeast Pacific Ocean using MWRI data. A double-difference calibration method is f...

This study compares the simulation biases of Advanced Himawari Imager (AHI) brightness temperature to observations made at night over China through the use of three land surface emissivity (LSE) datasets. The University of Wisconsin-Madison High Spectral Resolution Emissivity dataset, the Combined Advanced Spaceborne Thermal Emission and Reflection...

GOES-R satellite was successfully launched on November 19, 2016 with an Advanced Baseline Imager (ABI) on board. ABI is a new imager and provides more advanced capabilities for weather applications through more channels and higher temporal and spatial resolutions than the earlier GOES imagers. In this study, impacts from assimilating ABI brightness...

A recently refined hurricane warm-core retrieval algorithm was applied to data from multiple polar-orbiting satellites that carry the Advanced Technology Microwave Sounder (ATMS) and the Advanced Microwave Sounding Unit-A (AMSU-A) to examine the diurnal variability of the warm cores of Hurricanes Irma and Maria. These hurricanes occurred during the...

Pixel distortion reflects a change of the area and shape of the pixel observed by a geostationary imager with the location of the earth. The ability of detecting convective-scale weather phenomenon is determined by the pixel distortion, the location of the sub-satellite point and the pixel size at the sub-satellite point. If a geostationary meteoro...

The Microwave Radiation Imager (MWRI) on board Chinese Fengyun-3 (FY-3) satellites provides measurements at 10.65, 18.7, 23.8, 36.5, and 89.0 GHz with both horizontal and vertical polarization channels. Brightness temperature measurements of those channels with their central frequencies higher than 19 GHz from satellite-based microwave imager radio...

Measurements of brightness temperatures from Advanced Microwave Sounding Unit-A (AMSU-A) temperature sounding instruments onboard NOAA Polarorbiting Operational Environmental Satellites (POES) have been extensively used for studying atmospheric temperature trends over the past several decades. Intersensor biases, orbital drifts and diurnal variatio...

The Advanced Himawari Imager (AHI) onboard Japanese geostationary satellite Himawari-8 provides two more visible, three more near-infrared, and six more infrared channels than the only one visible and four infrared channels available from the previous geostationary imager instruments. By taking advantage of AHI's newly added channels 1, 3, and 4 wi...

The accuracy of simulated radiances for surface-sensitive visible and infrared channels is affected by the specification of surface type. The current version of Community Radiative Transfer Model (CRTM) employs three surface type data sets, which are referred to as the National Polar-orbiting Operational Environmental Satellite System (NPOESS), the...

The launch of the Japanese Advanced Himawari Imager (AHI) on 7 October 2014 represents a new era of geostationary operational environmental satellite (GOES) imagers, providing many more channels than any previously launched GOES imagers for the first time. In this study, we compare the impacts of assimilating all AHI versus GOES-like infrared chann...

The S-NPP ATMS upper air temperature sounding channels display a clear across-track striping noise in the NWP O-B fields. The striping magnitude variation is much more significant in ATMS along-track directions. Such a striping feature is also visible at brightness temperature fields at all 22 channels during an ATMS on-orbit pitch manoeuvre period...

The Global Precipitation Measurement (GPM) Microwave Imager (GMI) plays an important role in monitoring global precipitation. In this study, an along-track striping noise is found in GMI observations of brightness temperatures for the two highest-frequency channels-12 and 13-with their central frequencies centered at 183.31 GHz. These two channels...

The Cross-track Infrared Sounder (CrIS) on board the Suomi National Polar-Orbiting Partnership (S-NPP) satellite is a hyperspectral Fourier Transform Spectrometer. In this study, biases of the 399 channels used in numerical weather prediction applications are characterized based on the differences between CrIS observations and model simulations in...

GPS Radio Occultation (RO) cloudy profiles during a seven-year period from 2007 to 2013 over the globe are firstly selected and grouped into four types of ice clouds (e.g., nimbostratus, deep convective, cirrus, altostratus) based on collocated CloudSat data. Vertical temperature profiles within ice clouds below − 20 °C are then retrieved from GPS...

We collected global COSMIC RO data from 2009 and 2010 using measurements from the NOAA-18 Advanced Microwave Sounding Unit-A (AMSU-A) along GPS RO limb tracks and also using data from the CloudSat Cloud Profiling Radar (CPR). The collocated AMSU-A liquid water path (LWP) retrieval over the ocean is then used to quantify the dependence of fractional...

Two new constellations comprising 14 small satellites with microwave instruments onboard are proposed in this study. Properly arranged, the first constellation is capable of covering the entire globe at an hourly interval and the second constellation is more favorable for the tropical area. Compared to the current JPSS and MetOp satellite constella...

Detection of clouds within certain vertical layers of the atmospheric from satellite infrared instruments is challenging, especially of those optically thin clouds due to their small thermal contrasts to the background. This study develops a new method for cloud detection using the Cross-track Infrared Sounder (CrIS) hyperspectral radiances at shor...

Starting in 2014, the new generation of Japanese geostationary meteorological satellites carries an Advanced Himawari Imager (AHI) to provide the observations of visible, near infrared, and infrared with much improved spatial and temporal resolutions. For applications of the AHI measurements in numerical weather prediction (NWP) data assimilation s...

Since the launch of NOAA-15 satellite in 1998, the observations from microwave temperature and humidity sounders have been routinely disseminated to user communities through two separate data streams. In the Advanced Microwave Sounding Unit-A (AMSU-A) data stream, brightness temperatures at 15 channels are available primarily for profiling atmosphe...

The Advanced Technology Microwave Sounder (ATMS) is a cross-track microwave radiometer. Its temperature sounding channels 5-15 can provide measurements of thermal radiation emitted from different layers of the atmosphere. In this study, a traditional Advanced Microwave Sounding Unit-A (AMSU-A) temperature retrieval algorithm is modified to remove t...

Assimilation of infrared channel radiances from geostationary imagers requires an algorithm that can separate cloudy radiances from clear-sky ones. An infrared-only cloud mask (CM) algorithm has been developed using the Advanced Himawari Imager (AHI) radiance observations. It consists of a new CM test for optically thin clouds, two modified Advance...

The Advanced Microwave Scanning Radiometer 2 (AMSR2) measurements at K-band channels are used for snow retrieval. However, television (TV) signals transmitted from DirecTV satellites at the K-band, if reflected by snow surfaces, could enter the antenna of AMSR2 to introduce errors in AMSR2 snow products. This letter investigates TV frequency interf...

Microwave Humidity Sounder (MWHS) onboard the Chinese FengYun-3C satellite has a total of 12 channels. Eight of these channels are located near the 118-GHz oxygen absorption band for probing atmospheric temperature and humidity fields from space. While the water vapor sounding channels near 183 GHz have been extensively studied in the past, we repo...

Television (TV) radio frequency interference (TFI) signals are found in the Advanced Microwave Scanning Radiometer 2 (AMSR2) observations of those channels with their frequencies centered at 18.7- or 10.65-GHz frequencies over coastal regions near the U.S. and Europe, respectively. When TV signals are reflected off the ocean surface and get into AM...

The Advanced Technology Microwave Sounder (ATMS) onboard Suomi National Polar-orbiting Partnership satellite has 22 channels at frequencies ranging from 23 to 183 GHz for probing the atmospheric temperature and moisture under all weather conditions. As part of the ATMS calibration and validation activities, the geolocation accuracy of ATMS data mus...

This paper describes a new quality control (QC) scheme for microwave humidity sounder (MHS) data assimilation. It consists of a cloud detection step and an O–B (i.e., differences of brightness temperatures between observations and model simulations) check. Over ocean, cloud detection can be carried out based on two MHS window channels and two Advan...

This study demonstrates the importance of an early morning orbit satellite for improved coastal quantitative precipitation forecasts (QPFs) near the Gulf of Mexico. The Advanced Microwave Sounding Unit-A (AMSU-A) radiance observations from the early morning satellite NOAA-15, the mid-morning satellite MetOp-A, and the afternoon satellite NOAA-18, a...

Currently, the instrument sensitivity of sensors onboard weather satellites is quantified by computing the standard deviation of the measurements taken from their calibration targets. The standard deviation is valid for describing the spread of a statistical distribution of the measured values around its mean that is stable. However, the actual mea...

Comparisons between observations and background fields indicate that amplitude and phase differences in oscillations result in a non-Gaussian distribution in observation minus background vectors (OMB). Empirical Orthogonal Function (EOF) quality control (QC) and Fast Fourier Transform (FFT) quality control are proposed from the perspective of data...

The Atmospheric Infrared Sounder (AIRS) provides infrared radiance observations twice daily, which can be used to retrieve total column ozone with high spatial resolution. However, it was found that almost all of the ozone data within typhoons and hurricanes were flagged to be of bad quality by the AIRS original quality control (QC) scheme. This de...

Radio Frequency Interference (RFI) causes severe contamination to passive and active microwave sensing observations and corresponding retrieval products. RFI signals should be detected and filtered before applying the microwave data to retrieval and data assimilation. It is difficult to detect RFI over land surfaces covered by snow because of the s...