Large wildfires and their induced thunderstorms, pyrocumulonimbus (pyroCb), are getting increasing interest and attention. Most previous studies are based on broadband satellite data, and the use of hyperspectral infrared data for pyroCb detection has not been explored. Australia’s unprecedented fires at the end of 2019 to early 2020 induced an extreme pyroCb outbreak, and the largest event occurred on 30 December 2019 was successfully captured by the Cross-track Infrared Sounder (CrIS) onboard JPSS-1 and S-NPP. Analysis of these CrIS data demonstrated that the slopes and standard deviations of the spectral brightness temperature (BT), derived from a linear fitting to the spectrum in 800-980 cm-1, along with the split-window technique using selected CrIS channels, can aid in pyroCb detection. An inverted “V” feature in the spectra near 9.6 μm is associated with high pyroCb, and its depth, H_index, can provide information of cloud top height. These characteristics are verified through radiative transfer model (RTM) simulations and analysis of another case of pyroCb induced from California Creek fire on 5 September 2020. It is found that a combination of H_index and BT difference between 1231 and 677 cm-1is promising to distinguish high pyroCbs. A more accurate determination of pyroCb plume height can be achieved from the single Field of View Sounder Atmospheric Products (SiFSAP), which indicate that several pyroCb pixels reach 3-6 km above the tropopause. These approaches could be applied to study more pyroCbs using over 20 years of hyperspectral sounder data.

Different retrieval algorithms have been developed to process top-of-atmosphere (TOA) spectral radiance data provided by hyperspectral infrared sounder missions. Those algorithms are either optimal estimation method (OEM) based schemes with radiative transfer calculation involved in the retrieval process, or machine learning based methods that allow ultra-efficient data procession but lack of radiometric consistency validation based on the directly measured information. Combining both approaches leverages their respective technical advantages, leading to more accurate results. This study introduces a hyperspectral sounder fingerprinting algorithm to explore this hybrid approach. This approach involves the use of a spectral information-based classification method to identify an reference geophysical state and the corresponding radiative kernel. This enables the efficient retrieval of geophysical variables of interest through a radiative kernel-based linear inversion procedure. The fingerprinting method has been applied to analyze a decadelong hyperspectral sounder data record.

The Hunga Tonga-Hunga Ha'apai volcanic eruption, with the largest eruption occurring on 15 January 2022, ejected unprecedented amounts of water vapor (H2O) and SO2into the stratosphere. Using the hyperspectral infrared sounder CrIS on S-NPP and JPSS-1 (also NOAA-20), we present some unique features of the spectral near 9.6 μm and its great potential value for detecting plumes or clouds with tops near or above tropopause. We identified the existence of two umbrella clouds and observed the continued westward propagation of the upper plume even 8-9 hours after the eruption onset, as well as its dissipation from two CrIS observations onboard JPSS-1 and S-NPP taken in 50 minutes apart. Using a new Single Field-of-view Sounder Atmospheric Products (SiFSAP) from CrIS and ATMS on JPSS-1, which has a high spatial resolution of about 14 km, this study analyzes the impact of Hunga Tonga eruption on the distribution of temperature, H2O and ozone near the tropopause. These results demonstrate the value of hyperspectral infrared sounder and its single-field-view retrieval products for monitoring the volcanic eruptions and their impact on the lower stratosphere.

The Single Field-of-view Sounder Atmospheric Products (SiFSAP) answer the need for a novel high spatial resolution atmospheric data product for major hyper-spectral infrared (IR) sounder missions. SiFSAP include a complete set of atmospheric vertical profiles, cloud, and surface properties, which are physically retrieved from top-of-atmosphere (TOA) spectral radiances under all-sky conditions via a rigorously defined radiative transfer relationship. By using a state-of-art fast radiative transfer model and a carefully designed optimal estimation based physical retrieval scheme, the SiFSAP algorithm ensures both an ultra-fast data processing speed needed for operational weather applications and the radiometric consistency desired by long-term climate studies. SiFSAP supplement existing operational products by providing data at the native spatial resolution of the sounder instruments, the direct and accurate retrieval of cloud scattering properties, and the establishment of ‘radiance closure’.

The Single Field-of-view Sounder Atmospheric Products (SiFSAP), including ozone (0 3 ) and carbon monoxide (CO), from CrIS on SNPP have a spatial resolution of about 14 km at nadir. Such high-resolution sounder products enable us to make process-oriented analysis of CO emission and transport from large wildfires as well as the 0 3 production along the transport of fire plumes. An analysis of SiFSAP CO from Australia's unprecedented wildfires in the end of 2019 to early 2020, as well as comparison with satellite products from TROPOMI and MOPPIT and MERRA-2 reanalysis products, demonstrate an overall good agreement of CO observations among these space-borne sensors. This study also demonstrates the advantage of the SiFSAP CO in capturing the feature of CO transport and 0 3 production from wildfires, which will benefit air quality study.

The Single Field of View (SFOV) retrieval products from CrIS on SNPP have a spatial resolution of ∼ 0.15 by 0.15 degree. Such high resolution observations of the thermodynamic state of atmosphere may provide a very useful dataset to monitor the extreme weather events and strong dynamic transport process. This study compared the SFOV-retrieved temperature and water vapor with ERA5 reanalysis data for one polar vortex breakup case and one stratospheric intrusion event. The results show a good agreement between them in matching the large scale patterns but with some differences in the finer scale features. Comparison of the corresponding SFOV ozone with OMPS measurements demonstrated that the enhancement of ozone can be used to map the air transport. This study suggests that the SFOV sounding products may have a great value to help analyze the mechanism of dynamics, model diagnosis and weather forecasting.

The Ozone Mapping and Profiler Suite (OMPS) Nadir Profilers (NPs) are advanced backscatter ultraviolet (BUV) hyperspectral instruments that measure ozone profiles in the Earth atmosphere. The first NP sensor onboard the Suomi National Polar-orbiting Partnership (Suomi-NPP) satellite began its science observations on January 26, 2012, after its aperture door opened. The second OMPS NP, flying on the NOAA-20 satellite, opened its aperture door on January 8, 2018, starting science its data collection. The two NP sensors acquire Earth spectral images along their satellite flight path with a 16.7° wide swath, enabling weekly coverage of vertical ozone distribution in the Earth atmosphere. A successful thorough sensor calibration enables the NP sensors’ data records (SDRs) to meet measurement accuracy requirements. The largest error term in the albedo calibration came from the spectral wavelength calibration. This article provides SDRs accuracy analysis for both NP sensors and discusses important aspects of the SDRs performance in relation to the sensors’ characterization and calibration.

This paper presents a comparison of methane (CH4), one important greenhouse gas in terrestrial atmosphere, observed from two hyperspectral infrared sensors on satellites, one is the Atmospheric Infrared Sounder (AIRS) onboard NASA/AQUA and the other is the Infrared Atmospheric Sounding Interferometer (IASI) onboard METEOP-A and -B. Comparison using about 500 cases shows the mean DOFs from AIRS is slightly smaller than IASI, with the difference of -0.049±0.152. Overall the retrieved CH4from AIRS is larger than IASI, and their difference is 10.2±23.8 ppb below 650 hpa and 27.4±26.9 ppb above 350 hPa. In the most sensitive layer of infrared sounder between 350 and 650 hPa, their difference is as small as 2.8±17.2 ppb. Compared to aircraft measurements, AIRS retrievals tend to be overestimated while IASI retrievals tend to be underestimated in most cases, suggesting the necessarity to further improve the algorithms and call for more dedicated aircraft measurements for validation.

We perform a demonstration experiment using the National Oceanic Atmospheric Administration Unique Cross-track Infrared Sounder (CrIS)/Advanced Technology Microwave Sounder Processing System to assess the improvement on trace gas retrievals upon switching to high spectral resolution CrIS radiance measurements (0.625 cm-1). The focus of this study is carbon monoxide retrievals. The experimental high spectral resolution CO retrievals show a remarkable improvement, of almost up to one order of magnitude in the degree of freedom of the signal, with respect to the low-resolution mode. Furthermore, high-resolution CO retrievals show similar skill with respect to existing CO operational products from the Atmospheric InfraRed Sounder, Atmospheric Sounder Interferometer, and Measurements of Pollution In The Troposphere instruments, both in terms of spatial variability and degrees of freedom. The results of this research provide evidence to support the need for high spectral resolution CrIS measurements. This is a fundamental prerequisite in guaranteeing continuity to the CO afternoon orbit monitoring as part of a multisatellite uniformly integrated long-term data record of atmospheric trace gases.

China's industrialized regions have seen increasing occurrence of heavy haze caused by severe particle pollution. However, aerosol retrieval under these circumstances is often excluded from NASA's Moderate Resolution Imaging Spectrometer (MODIS) aerosol products due to cloud mask and suspected high surface reflectance. An algorithm to retrieve the haze aerosol optical thickness (HAOT) is developed using MODIS data to supplement the current MODIS retrieval algorithm. This method includes 1) haze identification, 2) the generation of a surface reflectance database using MODIS data in hazy conditions, and 3) the development of haze aerosol models with four aerosol components simulated by a global 3-D atmospheric chemical transport model (GEOS-Chem). This algorithm was used in combination with the MODIS dense dark vegetation algorithm to retrieve 1 km HAOT over North China Plain from March to September of 2008. The values of the retrieved HAOT values are mostly between 0.7–3, with a correlation coefficient of 0.82 with the Aerosol Robotic NETwork observations and a 19% mean relative difference. Retrieval uncertainties associated with the errors in haze detection, surface reflectance, and haze models were analyzed using ground measurements.

Atmospheric Vertical Temperature Profile (AVTP) and Atmospheric Vertical Moisture Profile (AVMP) retrievals produced by the Cross-track Infrared Sounder and the Advanced Technology Microwave Sounder suite (CrIMSS) official algorithm were evaluated with global European Center for Medium Range Weather Forecast (ECMWF) analysis fields, radiosonde (RAOB) measurements, and Aqua-Atmospheric Infrared Sounder (AIRS) heritage algorithm retrievals. The operational CrIMSS AVTP and AVMP product statistics with truth data sets are quite comparable to the AIRS heritage algorithm statistics. Planned updates and improvements to the CrIMSS algorithm will alleviate many issues observed with `day-one' focus-day results and show promise in meeting the Key Performance Parameter (KPP) specifications.

As a part of the Joint Polar Satellite System (JPSS) and the Suomi National Polar-orbiting Partnership (NPP), the Cross-track Infrared Sounder (CrIS) and Advanced Technology Microwave Sounder (ATMS) instruments make up the Cross-track Infrared and Microwave Sounder Suite (CrIMSS). CrIMSS primarily provides globally-referenced calibrated radiances and vertical profiles of temperature, moisture, and pressure. The CrIMSS operational code has been ported to various LINUX systems and retrievals are performed using both proxy and real ATMS/CrIS data. The high quality proxy data generated from the IASI instrument provided useful testing for the CrIMSS EDR algorithm prior to the launch of the SUOMI NPP satellite. The experience learned from processing the proxy data helped us to handle the SUOMI NPP CrIS/ATMS data as soon as they became available to the CAL/VAL team. In this paper, encouraging preliminary results of applying the ported CrIMSS EDR algorithm to the SUOMI NPP CrIS/ATMS data are presented.