Using OSSEs to Evaluate the Impacts of Geostationary Infrared Sounders

McGrath-Spangler, E. L.; McCarty, Will; Privé, Nikki C.; Moradi, Isaac; Karpowicz, Bryan M.; McCorkel, Joel

doi:10.1175/jtech-d-22-0033.1

Cited by 4 publications

(4 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, these results can be supported by a similar study conducted by (McGrath‐Spangler et al ., 2022). That study was also carried out using an OSSE and concerns the evaluation of the impact of assimilating infrared observations from a hyperspectral sounder on board a geostationary satellite on the NWP, within the framework of the GeoXO programme in the United States.…”

Section: Assimilation Experiments and Resultsmentioning

confidence: 99%

Preparing the assimilation of the future MTG‐IRS sounder into the mesoscale numerical weather prediction AROME model

Coopmann,

Fourrié,

Chambon

et al. 2023

Quart J Royal Meteoro Soc

View full text Add to dashboard Cite

The IRS (InfraRed Sounder) instrument is an infrared Fourier transform spectrometer that will be on board the Meteosat Third Generation series of the future EUMETSAT geostationary satellites. It will measure the radiance emitted by the Earth at the top of the atmosphere using 1960 channels. IRS will provide high spatial and temporal frequency 4D information on atmospheric temperature and humidity, winds, clouds, surfaces, as well as on the chemical composition of the atmosphere. The assimilation of these new observations represents a great challenge and opportunity for the improvement of Numerical Weather Prediction (NWP) forecast skill, especially for mesoscale models such as AROME at Météo‐France (Brousseau et al. 2016). The objectives of this study are to prepare for the assimilation of IRS in this system and to evaluate its impact on the forecasts when added to the currently assimilated observations.By using an Observing System Simulation Experiment (OSSE) constructed for a mesoscale NWP model. This OSSE framework makes use of synthetic observations of both IRS and the currently assimilated observing systems in AROME, constructed from a known and realistic state of the atmosphere. The latter, called the Nature Run, is derived from a long and uninterrupted forecast of the mesoscale model. These observations were assimilated and evaluated using a 1 h update cycle 3D‐Var data assimilation system over two‐month periods, one in the summer and one in the winter.This study demonstrates the benefits that can be expected from the assimilation of IRS observations into AROME NWP system. The assimilation of only 75 channels over oceans increases the total amount of observations used in the AROME 3D‐Var by about 50 %. The IRS impact in terms of forecast scores was evaluated and compared for the summer and winter periods. The main findings are that (i) over both periods the assimilation of these observations lead to statistically improved forecasts over the whole atmospheric column, (ii) for the summer season experiment, the forecast ranges up to +48h are improved, (iii) for the winter season experiment, the impact on the forecasts is globally positive but is smaller compared to the summer period and extends only to 24 h. Based on these results, it is foreseen that the addition of future IRS observations in the AROME NWP systems will significantly improve mesoscale weather forecasts.This article is protected by copyright. All rights reserved.

show abstract

Section: Assimilation Experiments and Resultsmentioning

confidence: 99%

Preparing the assimilation of the future MTG‐IRS sounder into the mesoscale numerical weather prediction AROME model

Coopmann,

Fourrié,

Chambon

et al. 2023

Quart J Royal Meteoro Soc

View full text Add to dashboard Cite

show abstract

“…The Previous version of the GMAO OSSE framework used the GEOS/GSI versions that were in use quasi-operationally in 2018, with simulated observations based on the global observing network in 2015. That version has been extensively documented (Errico et al, 2013;2017;Privé et al, 2021;El Akkraoui et al, 2023), and multiple OSSE studies have been performed using that framework (Privé et al, 2022;McGrath-Spangler et al, 2022;Privé et al, 2023). The following discussion will give a brief overview of the GMAO NWP OSSE framework, with focus on the changes implemented in the Updated version.…”

Section: Osse Frameworkmentioning

confidence: 99%

“…The largest improvement occurring in the tropics is expected because these are the latitudes with the broadest observational coverage by a geostationary orbit. However, there is a degradation south of approximately 30°S associated with an increased error off the west coast of South America (McGrath-Spangler et al, 2022). An even larger temperature degradation exists near the South Polar tropopause, outside the coverage of the assimilated GEO IR satellite observations.…”

Section: Geostationary Hyperspectral Infrared (Ir)mentioning

confidence: 99%

“…Several new observing types were tested in both the Previous and Updated OSSE frameworks. These instruments are the Geostationary eXtended Observations (GeoXO) hyperspectral infrared sounder (GXS) (McGrath-Spangler et al, 2022), additional Global Navigation Satellite System Radio Occultation (GNSS-RO) observations (Privé et al, 2022), and atmospheric motion vectors for the Midwave Infrared Sounding of Temperature and humidity in a Constellation for Winds (MISTiC Winds) instrument (McCarty et al, 2021). Select experiments for each of these instruments were repeated in both OSSE frameworks to compare how the observation impacts of the new instruments are affected by the framework used.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Robustness of Observing System Simulation Experiments

Privé,

McGrath-Spangler,

Carvalho

et al. 2023

Tellus A: Dynamic Meteorology and Oceanography

Self Cite

View full text Add to dashboard Cite

Observing System Simulation Experiments (OSSEs) are used to investigate the potential performance of proposed new instruments on numerical weather prediction (NWP). As OSSEs involve a framework in which the atmosphere and observations are all completely simulated, it is necessary to perform validation of the OSSE to ensure that it is sufficiently realistic to provide useful experimental results. A common issue that affects the forecast skill and observation impacts is the tendency of OSSEs to have insufficient model error compared to NWP in the real world. In this work, two versions of the National Aeronautics and Space Administration Global Modeling and Assimilation Office (NASA/GMAO) NWP OSSE framework are compared, with the newer framework having more simulated forecast model error than the older framework due to changes to the NWP system. The performance of the updated OSSE is validated against corresponding behavior of the same NWP system in the real world in terms of the simulated observations, the analysis increments, forecast error, and observation impacts. OSSE results of analysis and forecast impacts for three proposed new observation systems are also compared between the older and newer frameworks to evaluate the robustness of the OSSE experiments and the role of model error in observation impacts. These three new instruments are the Geostationary eXtended Observations (GeoXO) hyperspectral infrared sounder (GXS), the Midwave Infrared Sounding of Temperature and humidity in a Constellation for Winds (MISTiC Winds) atmospheric motion vectors, and additional Global Navigation Satellite System Radio Occultations (GNSS-RO).

show abstract

Extension of all‐sky radiance assimilation to hyperspectral infrared sounders

Okamoto,

Ishibashi,

Okabe

et al. 2024

Quart J Royal Meteoro Soc

View full text Add to dashboard Cite

This study accomplished the all‐sky infrared (IR) radiance assimilation of the hyperspectral IR sounders of the IR atmospheric sounding interferometer in the Japan Meteorological Agency's global system. Essential assimilation procedures, including cloud‐dependent quality control, bias correction, and observation‐error modeling, were directly adapted from the all‐sky assimilation of geostationary satellite imagers in our previous study, without any sophisticated modifications. Data assimilation experiments conducted in different seasons demonstrated that, compared with clear‐sky radiance assimilation, the all‐sky radiance assimilation of three channels sensitive to mid and upper tropospheric water vapor yielded significant forecast improvements in not only humidity but also temperature, wind, and geopotential height. These improvements originated from more than twofold increments in the number of globally assimilated observations under the all‐sky approach and better observation coverages. Increasing the number of assimilated channels to nine further amplified these improvements. The incorporation of an upper tropospheric channel mitigated upper tropospheric humidity biases that were originally exacerbated during three‐channel assimilation. These results underscore the broad applicability of the all‐sky assimilation approach to various IR instruments.

show abstract

Using OSSEs to Evaluate the Impacts of Geostationary Infrared Sounders

Cited by 4 publications

References 50 publications

Preparing the assimilation of the future MTG‐IRS sounder into the mesoscale numerical weather prediction AROME model

Preparing the assimilation of the future MTG‐IRS sounder into the mesoscale numerical weather prediction AROME model

Robustness of Observing System Simulation Experiments

Extension of all‐sky radiance assimilation to hyperspectral infrared sounders

Contact Info

Product

Resources

About