Application of φ-IASI to IASI: retrieval products evaluation and radiative transfer consistency

Abstract. Retrieval products for temperature, water vapour and ozone have been obtained from spectral radiances measured by the Infrared Atmospheric Sounding Interferometer flying onboard the first European Meteorological Operational satellite. These products have been used to check the consistency of the forward model and its accuracy and the expected retrieval performance. The study has been carried out using a research-oriented forward-inverse methodology, called φ-IASI, that the authors have specifically developed for the new sounding interferometer. The performance of the forward-inversion strategy has been assessed by comparing the retrieved profiles to profiles of temperature, water vapour and ozone obtained by co-locating in space and time profiles from radiosonde observations and from the European Centre for Medium-Range Weather Forecasts analysis. Spectral residuals have also been computed and analyzed to assess the quality of the forward model. Two versions of the high-resolution transmission molecular absorption database have been used. Their performance has been assessed by inter-comparing the results.

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Application of φ-IASI to IASI: retrieval products evaluation and radiative transfer consistency

Atmospheric Chemistry and Physics ◽

10.5194/acp-9-8771-2009 ◽

2009 ◽

Vol 9 (22) ◽

pp. 8771-8783 ◽

Cited By ~ 30

Author(s):

G. Masiello ◽

C. Serio ◽

A. Carissimo ◽

G. Grieco ◽

M. Matricardi

Keyword(s):

Water Vapour ◽

Forward Model ◽

Continuum Absorption ◽

Weather Forecasts ◽

Time Profiles ◽

Spectral Residual ◽

Atmospheric Sounding ◽

Medium Range ◽

Temperature Water

Abstract. Retrieval products for temperature, water vapour and ozone have been obtained from spectral radiances measured by the Infrared Atmospheric Sounding Interferometer flying onboard the first European Meteorological Operational satellite. These products have been used to check the consistency of the forward model and its accuracy and the expected retrieval performance. The study has been carried out using a research-oriented forward-inverse methodology, called φ-IASI, that the authors have specifically developed for the new sounding interferometer. The performance of the forward-inversion strategy has been assessed by comparing the retrieved profiles to profiles of temperature, water vapour and ozone obtained by co-locating in space and time profiles from radiosonde observations and from the European Centre for Medium-Range Weather Forecasts analysis. Spectral residuals have also been computed and analyzed to assess the quality of the forward model. Two versions of the high-resolution transmission molecular absorption database have been used, which mostly differ for ozone absorption line parameters, line and continuum absorption of both CO2 and H2O molecules. Their performance has been assessed by inter-comparing the results, and a consistent improvement in the spectral residual has been found when using the most updated release.

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Technical Note: Functional sliced inverse regression to infer temperature, water vapour and ozone from IASI data

Atmospheric Chemistry and Physics ◽

10.5194/acp-9-5321-2009 ◽

2009 ◽

Vol 9 (14) ◽

pp. 5321-5330 ◽

Cited By ~ 24

Author(s):

U. Amato ◽

A. Antoniadis ◽

I. De Feis ◽

G. Masiello ◽

M. Matricardi ◽

...

Keyword(s):

Water Vapour ◽

Technical Note ◽

Retrieval Algorithm ◽

Inverse Regression ◽

Weather Forecasts ◽

Time Profiles ◽

Statistical Strategy ◽

Atmospheric Sounding ◽

Medium Range ◽

Temperature Water

Abstract. A retrieval algorithm that uses a statistical strategy based on dimension reduction is proposed. The methodology and details of the implementation of the new algorithm are presented and discussed. The algorithm has been applied to high resolution spectra measured by the Infrared Atmospheric Sounding Interferometer instrument to retrieve atmospheric profiles of temperature, water vapour and ozone. The performance of the inversion strategy has been assessed by comparing the retrieved profiles to the ones obtained by co-locating in space and time profiles from the European Centre for Medium-Range Weather Forecasts analysis.

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Technical note: Functional sliced inverse regression to infer temperature, water vapour and ozone from IASI data

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-9-7589-2009 ◽

2009 ◽

Vol 9 (2) ◽

pp. 7589-7613 ◽

Cited By ~ 1

Author(s):

U. Amato ◽

A. Antoniadis ◽

I. De Feis ◽

G. Masiello ◽

M. Matricardi ◽

...

Keyword(s):

Water Vapour ◽

Technical Note ◽

Retrieval Algorithm ◽

Inverse Regression ◽

Weather Forecasts ◽

Time Profiles ◽

Statistical Strategy ◽

Atmospheric Sounding ◽

Medium Range ◽

Temperature Water

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An “island” in the stratosphere – on the enhanced annual variation of water vapour in the middle and upper stratosphere in the southern tropics and subtropics

Atmospheric Chemistry and Physics ◽

10.5194/acp-17-11521-2017 ◽

2017 ◽

Vol 17 (18) ◽

pp. 11521-11539 ◽

Cited By ~ 3

Author(s):

Stefan Lossow ◽

Hella Garny ◽

Patrick Jöckel

Keyword(s):

Water Vapour ◽

Atmospheric Chemistry ◽

Annual Variation ◽

Trace Gases ◽

Michelson Interferometer ◽

Full Account ◽

Weather Forecasts ◽

European Centre ◽

Atmospheric Sounding ◽

Medium Range

Abstract. The amplitude of the annual variation in water vapour exhibits a distinct isolated maximum in the middle and upper stratosphere in the southern tropics and subtropics, peaking typically around 15° S in latitude and close to 3 hPa (∼  40.5 km) in altitude. This enhanced annual variation is primarily related to the Brewer–Dobson circulation and hence also visible in other trace gases. So far this feature has not gained much attention in the literature and the present work aims to add more prominence. Using Envisat/MIPAS (Environmental Satellite/Michelson Interferometer for Passive Atmospheric Sounding) observations and ECHAM/MESSy (European Centre for Medium-Range Weather Forecasts Hamburg/Modular Earth Submodel System) Atmospheric Chemistry (EMAC) simulations we provide a dedicated illustration and a full account of the reasons for this enhanced annual variation.

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An assessment of the accuracy of the RTTOV fast radiative transfer model using IASI data

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-9-9491-2009 ◽

2009 ◽

Vol 9 (2) ◽

pp. 9491-9535 ◽

Cited By ~ 8

Author(s):

M. Matricardi

Keyword(s):

Radiative Transfer ◽

Regression Coefficients ◽

Radiative Transfer Model ◽

Transfer Model ◽

Weather Forecasts ◽

Medium Range ◽

Forecasting System ◽

Relative Differences ◽

Temperature Water

Abstract. IASI measurements of spectral radiances made between the 1 April 2008 and the 15 April 2008 are compared with simulations performed using the RTTOV fast radiative transfer model utilizing regression coefficients based on different line-by-line models. The comparisons are performed within the framework of the European Centre for Medium-Range Weather Forecasts Integrated Forecasting System using fields of temperature, water vapour and ozone obtained from short-range forecasts. Simulations are performed to assess the accuracy of the RTTOV computations and investigate relative differences between the line-by-line models and the quality of the spectroscopic databases on which the RTTOV coefficients are based.

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An island in the stratosphere – On the enhanced annual variation of water vapour in the middle and upper stratosphere in the southern tropics and subtropics

10.5194/acp-2017-392 ◽

2017 ◽

Cited By ~ 1

Author(s):

Stefan Lossow ◽

Hella Garny ◽

Patrick Jöckel

Keyword(s):

Water Vapour ◽

Atmospheric Chemistry ◽

Annual Variation ◽

Trace Gases ◽

Michelson Interferometer ◽

Full Account ◽

Weather Forecasts ◽

European Centre ◽

Atmospheric Sounding ◽

Medium Range

Abstract. The annual variation of water vapour exhibits a distinct isolated maximum in the middle and upper stratosphere in the southern tropics and subtropics, peaking typically around 15° S in latitude and close to 3 hPa (~ 40.5 km) in altitude. This enhanced annual variation is primarily related to the Brewer–Dobson circulation and hence also visible in other trace gases. So far this feature has not gained much attention in the literature and the present work aims to add more prominence. Using Envisat/MIPAS (Environmental Satellite/Michelson Interferometer for Passive Atmospheric Sounding) observations and ECHAM/MESSy (European Centre for Medium-Range Weather Forecasts Hamburg/Modular Earth Submodel System) Atmospheric Chemistry (EMAC) simulations we provide a dedicated illustration and a full account for the reasons of this enhanced annual variation.

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Technical Note: An assessment of the accuracy of the RTTOV fast radiative transfer model using IASI data

Atmospheric Chemistry and Physics ◽

10.5194/acp-9-6899-2009 ◽

2009 ◽

Vol 9 (18) ◽

pp. 6899-6913 ◽

Cited By ~ 31

Author(s):

M. Matricardi

Keyword(s):

Radiative Transfer ◽

Technical Note ◽

Regression Coefficients ◽

Radiative Transfer Model ◽

Transfer Model ◽

Weather Forecasts ◽

Medium Range ◽

Relative Differences ◽

Temperature Water

Abstract. IASI measurements of spectral radiances made between the 1st April 2008 and the 15th April 2008 are compared with simulations performed using the RTTOV fast radiative transfer model utilizing regression coefficients based on different line-by-line models. The comparisons are performed within the framework of the European Centre for Medium-Range Weather Forecasts Integrated Forecast System using fields of temperature, water vapour and ozone obtained from short-range forecasts. Simulations are performed to assess the accuracy of the RTTOV computations and investigate relative differences between the line-by-line models and the quality of the spectroscopic databases on which the RTTOV coefficients are based.

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Validation of SCIAMACHY AMC-DOAS water vapour columns

Atmospheric Chemistry and Physics ◽

10.5194/acp-5-1835-2005 ◽

2005 ◽

Vol 5 (7) ◽

pp. 1835-1841 ◽

Cited By ~ 31

Author(s):

S. Noël ◽

M. Buchwitz ◽

H. Bovensmann ◽

J. P. Burrows

Keyword(s):

Water Vapour ◽

Visible Spectral Region ◽

Optical Absorption Spectroscopy ◽

Data Sets ◽

Monthly Means ◽

Data Set ◽

Weather Forecasts ◽

Microwave Imager ◽

Scanning Imaging

Abstract. A first validation of water vapour total column amounts derived from measurements of the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) in the visible spectral region has been performed. For this purpose, SCIAMACHY water vapour data have been determined for the year 2003 using an extended version of the Differential Optical Absorption Spectroscopy (DOAS) method, called Air Mass Corrected (AMC-DOAS). The SCIAMACHY results are compared with corresponding water vapour measurements by the Special Sensor Microwave Imager (SSM/I) and with model data from the European Centre for Medium-Range Weather Forecasts (ECMWF). In confirmation of previous results it could be shown that SCIAMACHY derived water vapour columns are typically slightly lower than both SSM/I and ECMWF data, especially over ocean areas. However, these deviations are much smaller than the observed scatter of the data which is caused by the different temporal and spatial sampling and resolution of the data sets. For example, the overall difference with ECMWF data is only -0.05 g/cm2 whereas the typical scatter is in the order of 0.5 g/cm2. Both values show almost no variation over the year. In addition, first monthly means of SCIAMACHY water vapour data have been computed. The quality of these monthly means is currently limited by the availability of calibrated SCIAMACHY spectra. Nevertheless, first comparisons with ECMWF data show that SCIAMACHY (and similar instruments) are able to provide a new independent global water vapour data set.

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Choices in the Verification of S2S Forecasts and Their Implications for Climate Services

Monthly Weather Review ◽

10.1175/mwr-d-20-0067.1 ◽

2020 ◽

Vol 148 (10) ◽

pp. 3995-4008

Author(s):

Andrea Manrique-Suñén ◽

Nube Gonzalez-Reviriego ◽

Verónica Torralba ◽

Nicola Cortesi ◽

Francisco J. Doblas-Reyes

Keyword(s):

Skill Score ◽

Climate Services ◽

Near Surface ◽

Weather Forecasts ◽

Probabilistic Evaluation ◽

Skill Scores ◽

Medium Range ◽

The Impact ◽

Start Dates

AbstractSubseasonal predictions bridge the gap between medium-range weather forecasts and seasonal climate predictions. This time scale is crucial for operations and planning in many sectors such as energy and agriculture. For users to trust these predictions and efficiently make use of them in decision-making, the quality of predicted near-surface parameters needs to be systematically assessed. However, the method to follow in a probabilistic evaluation of subseasonal predictions is not trivial. This study aims to offer an illustration of the impact that the verification setup might have on the calculation of the skill scores, thus providing some guidelines for subseasonal forecast evaluation. For this, several forecast verification setups to calculate the fair ranked probability skill score for tercile categories have been designed. These setups use different number of samples to compute the fair RPSS as well as different ways to define the climatology, characterized by different time periods to average (week or month). These setups have been tested by evaluating 2-m temperature in ECMWF-Ext-ENS 20-yr hindcasts for all of the initializations in 2016 against the ERA-Interim reanalysis. Then, the implications on skill score values of each of the setups are analyzed. Results show that to obtain a robust skill score several start dates need to be employed. It is also shown that a constant monthly climatology over each calendar month may introduce spurious skill score associated with the seasonal cycle. A weekly climatology bears similar results to a monthly running-window climatology; however, the latter provides a better reference climatology when bias adjustment is applied.

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Technical and operational characteristics of GPS radiosounding system in the upper air network of IMD

MAUSAM ◽

10.54302/mausam.v62i3.318 ◽

2021 ◽

Vol 62 (3) ◽

pp. 403-416

Author(s):

GAJENDRA KUMAR ◽

RANJU MADAN ◽

K.C. SAIKRISHNAN ◽

S.K. KUNDU ◽

P.K. JAIN

Keyword(s):

Global Positioning System ◽

Weather Forecasting ◽

Quality Change ◽

Weather Forecasts ◽

National Centre ◽

Operational Characteristics ◽

Global Positioning ◽

Medium Range ◽

Black List

In recent years, the upper air radiosounding system based on Global Positioning System (GPS) is used as an effective method. GPS receiving device in a Radiosonde improves observation accuracy, allowing simplification of ground equipment. To get improved quality of upper air data, ten stations have been upgraded with new upper air systems based on GPS. This paper describes the upper air radiosounding system that adopts the GPS. After the introduction of GPS Radiosonde in the network at 10 places, data quality has improved substantially at these stations, which has been validated by National Centre for Medium Range Weather Forecasting (NCMRWF) and European Centre for Medium-Range Weather Forecasts (ECMWF). In all cases the quality change has been remarkable and as a result black list tag is removed by ECMWF for the Indian GPS stations.

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