An Improvement in Forecasting Rapid Intensification of Typhoon Sinlaku (2008) Using Clear-Sky Full Spatial Resolution Advanced IR Soundings

Abstract Hyperspectral infrared (IR) sounders, such as the Atmospheric Infrared Sounder (AIRS) and the Infrared Atmospheric Sounding Interferometer (IASI), provide unprecedented global atmospheric temperature and moisture soundings with high vertical resolution and accuracy. In this paper, the authors investigate whether advanced IR soundings of water vapor and temperature observations can improve the analysis of a tropical cyclone vortex and the forecast of rapid intensification of a tropical cyclone. Both the IR water vapor and temperature soundings significantly improve the typhoon vortex in the analysis and the forecast of the rapid intensification of Typhoon Sinlaku (2008). The typhoon track forecast is also substantially improved when the full spatial resolution AIRS soundings are assimilated. This study demonstrates the potential important application of high spatial and hyperspectral IR soundings in forecasting tropical cyclones.

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Progress toward Cloud-Cleared Infrared radiance assimilation in a global modeling framework: Application to the 2017 Atlantic Tropical Cyclone Season.

10.5194/egusphere-egu21-2870 ◽

2021 ◽

Author(s):

Niama Boukachaba ◽

Oreste Reale ◽

Erica L. McGrath-Spangler ◽

Manisha Ganeshan ◽

Will McCarty ◽

...

Keyword(s):

Tropical Cyclone ◽

Strong Impact ◽

Modeling Framework ◽

Atmospheric Infrared Sounder ◽

Clear Sky ◽

Earth Observing System ◽

Infrared Radiance ◽

Radiance Assimilation ◽

The Impact ◽

Tropical Cyclone Season

Previous work by this team has demonstrated that assimilation of IR radiances in partially cloudy regions is beneficial to numerical weather predictions (NWPs), improving the representation of tropical cyclones (TCs) in global analyses and forecasts. The specific technique used by this team is based on the &#8220;cloud-clearing CC&#8221; methodology. Cloud-cleared hyperspectral IR radiances (CCRs), if thinned more aggressively than clear-sky radiances, have shown a strong impact on the analyzed representation and structure of TCs. However, the use of CCRs in an operational context is limited by 1) latency; and 2) external dependencies present in the original cloud-clearing algorithm. In this study, the Atmospheric InfraRed Sounder (AIRS) CC algorithm was (a) ported to NASA high end computing resources (HEC), (b) deprived of external dependencies, and (c) parallelized improving the processing by a factor of 70. The revised AIRS CC algorithm is now customizable, allowing user&#8217;s choice of channel selection, user&#8217;s model's fields as first guess, and could perform in real time. This study examines the benefits achieved when assimilating CCRs using the NASA&#8217;s Goddard Earth Observing System (GEOS) hybrid 4DEnVar system. The focus is on the 2017 Atlantic hurricane season with three infamous hurricanes (Harvey, Irma, and Maria) investigated in depth.&#160; The impact of assimilating customized CCRs on the analyzed representation of tropical cyclone horizontal and vertical structure and on forecast skill is discussed.

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The Impact of Dropwindsonde Data on Typhoon Track Forecasts in DOTSTAR

Weather and Forecasting ◽

10.1175/2007waf2006062.1 ◽

2007 ◽

Vol 22 (6) ◽

pp. 1157-1176 ◽

Cited By ~ 80

Author(s):

Chun-Chieh Wu ◽

Kun-Hsuan Chou ◽

Po-Hsiung Lin ◽

Sim D. Aberson ◽

Melinda S. Peng ◽

...

Keyword(s):

Tropical Cyclone ◽

Error Reduction ◽

Track Forecast ◽

Cyclone Track ◽

Tropical Cyclone Track ◽

Global Spectral Model ◽

Track Error ◽

Typhoon Track ◽

The Mean ◽

The Impact

Abstract Starting from 2003, a new typhoon surveillance program, Dropwindsonde Observations for Typhoon Surveillance near the Taiwan Region (DOTSTAR), was launched. During 2004, 10 missions for eight typhoons were conducted successfully with 155 dropwindsondes deployed. In this study, the impact of these dropwindsonde data on tropical cyclone track forecasts has been evaluated with five models (four operational and one research models). All models, except the Geophysical Fluid Dynamics Laboratory (GFDL) hurricane model, show the positive impact that the dropwindsonde data have on tropical cyclone track forecasts. During the first 72 h, the mean track error reductions in the National Centers for Environmental Prediction’s (NCEP) Global Forecast System (GFS), the Navy Operational Global Atmospheric Prediction System (NOGAPS) of the Fleet Numerical Meteorology and Oceanography Center (FNMOC), and the Japanese Meteorological Agency (JMA) Global Spectral Model (GSM) are 14%, 14%, and 19%, respectively. The track error reduction in the Weather Research and Forecasting (WRF) model, in which the initial conditions are directly interpolated from the operational GFS forecast, is 16%. However, the mean track improvement in the GFDL model is a statistically insignificant 3%. The 72-h-average track error reduction from the ensemble mean of the above three global models is 22%, which is consistent with the track forecast improvement in Atlantic tropical cyclones from surveillance missions. In all, despite the fact that the impact of the dropwindsonde data is not statistically significant due to the limited number of DOTSTAR cases in 2004, the overall added value of the dropwindsonde data in improving typhoon track forecasts over the western North Pacific is encouraging. Further progress in the targeted observations of the dropwindsonde surveillances and satellite data, and in the modeling and data assimilation system, is expected to lead to even greater improvement in tropical cyclone track forecasts.

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Comparisons of the Millimeter and Submillimeter Bands for Atmospheric Temperature and Water Vapor Soundings for Clear and Cloudy Skies

Journal of Applied Meteorology and Climatology ◽

10.1175/jam2438.1 ◽

2006 ◽

Vol 45 (12) ◽

pp. 1622-1633 ◽

Cited By ~ 18

Author(s):

Catherine Prigent ◽

Juan R. Pardo ◽

William B. Rossow

Keyword(s):

Water Vapor ◽

Spatial Resolution ◽

Atmospheric Temperature ◽

Submillimeter Wave ◽

Severe Weather ◽

High Frequencies ◽

Geostationary Satellites ◽

Potential Applications ◽

Cloud Ice ◽

The Impact

Abstract Geostationary satellites provide revisiting times that are desirable for nowcasting and observations of severe weather. To overcome the problem of spatial resolution from a geostationary orbit, millimeter to submillimeter wave sounders have been suggested. This study compares the capabilities of various oxygen and water vapor millimeter and submillimeter bands for temperature and water vapor atmospheric profiling at nadir in cloudy situations. It shows the impact of different cloud types on the received signal for the different frequency bands. High frequencies are very sensitive to the cloud ice phase, with potential applications to cirrus characterization.

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Impact of Adaptively Thinned AIRS Cloud-Cleared Radiances on Tropical Cyclone Representation in a Global Data Assimilation and Forecast System

Weather and Forecasting ◽

10.1175/waf-d-17-0175.1 ◽

2018 ◽

Vol 33 (4) ◽

pp. 909-931 ◽

Cited By ~ 7

Author(s):

Oreste Reale ◽

Erica L. McGrath-Spangler ◽

Will McCarty ◽

Daniel Holdaway ◽

Ronald Gelaro

Keyword(s):

Tropical Cyclone ◽

Data Assimilation ◽

Forecast Model ◽

Adaptive Strategy ◽

Atmospheric Infrared Sounder ◽

Full Agreement ◽

Clear Sky ◽

Earth Observing System ◽

Moving Domain ◽

Global Data

Abstract A simple adaptive thinning methodology for Atmospheric Infrared Sounder (AIRS) radiances is evaluated through a combination of observing system experiments (OSEs) and adjoint methodologies. The OSEs are performed with the NASA Goddard Earth Observing System (GEOS, version 5) data assimilation and forecast model. In addition, the adjoint-based forecast sensitivity observation impact technique is applied to assess fractional contributions of sensors in different thinning configurations. The adaptive strategy uses a denser AIRS coverage in a moving domain centered around tropical cyclones (TCs) but sparser everywhere else. The OSEs consist of two sets of data assimilation runs that cover the period from 1 September to 10 November 2014, with the first 20 days discarded for spinup. Both sets assimilate all conventional and satellite observations used operationally. In addition, one ingests clear-sky AIRS radiances, the other cloud-cleared radiances, each comprising multiple thinning strategies. Daily 7-day forecasts are initialized from all these analyses and evaluated with a focus on TCs over the Atlantic and Pacific. Evidence is provided on the effectiveness of this simple TC-centered adaptive radiance thinning strategy, in full agreement with previous theoretical studies. Specifically, global skill increases, and tropical cyclone representation is substantially improved. The improvement is particularly strong when cloud-cleared radiances are assimilated. Finally, the article suggests that cloud-cleared radiances, if thinned more aggressively than the currently used clear-sky radiances, could successfully replace them with large improvements in TC forecasting and no loss of global skill.

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An investigation of the sensitivity of the clear-sky outgoing longwave radiation to atmospheric temperature and water vapor

Journal of Geophysical Research Atmospheres ◽

10.1029/2005jd006906 ◽

2007 ◽

Vol 112 (D5) ◽

Cited By ~ 31

Author(s):

Yi Huang ◽

V. Ramaswamy ◽

Brian Soden

Keyword(s):

Water Vapor ◽

Outgoing Longwave Radiation ◽

Longwave Radiation ◽

Atmospheric Temperature ◽

Clear Sky

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Evaluation and Improvement of the Quality of Ground-Based Microwave Radiometer Clear-Sky Data

Atmosphere ◽

10.3390/atmos12040435 ◽

2021 ◽

Vol 12 (4) ◽

pp. 435

Author(s):

Qing Li ◽

Ming Wei ◽

Zhenhui Wang ◽

Yanli Chu

Keyword(s):

Water Vapor ◽

Temperature Inversion ◽

Atmospheric Temperature ◽

Radiosonde Data ◽

Vapor Density ◽

Clear Sky ◽

Brightness Temperatures ◽

Temperature And Humidity ◽

Humidity Profiles

To assess the quality of the retrieved products from ground-based microwave radiometers, the “clear-sky” Level-2 data (LV2) products (profiles of atmospheric temperature and humidity) filtered through a radiometer in Beijing during the 24 months from January 2010 to December 2011 were compared with radiosonde data. Evident differences were revealed. Therefore, this paper investigated an approach to calibrate the observed brightness temperatures by using the model-simulated brightness temperatures as a reference under clear-sky conditions. The simulation was completed with a radiative transfer model and National Centers for Environmental Prediction final analysis (NCEP FNL) data that are independent of the radiometer system. Then, the least-squares method was used to invert the calibrated brightness temperatures to the atmospheric temperature and humidity profiles. A comparison between the retrievals and radiosonde data showed that the calibration of the brightness temperature observations is necessary, and can improve the inversion of temperature and humidity profiles compared with the original LV2 products. Specifically, the consistency with radiosonde was clearly improved: the correlation coefficients are increased, especially, the correlation coefficient for water vapor density increased from 0.2 to 0.9 around the 3 km height; the bias decreased to nearly zero at each height; the RMSE (root of mean squared error) for temperature profile was decreased by more than 1 degree at most heights; the RMSE for water vapor density was decreased from greater than 4 g/m3 to less than 1.5 g/m3 at 1 km height; and the decrease at all other heights were also noticeable. In this paper, the evolution of a temperature inversion process is given as an example, using the high-temporal-resolution brightness temperature after quality control to obtain a temperature and humidity profile every two minutes. Therefore, the characteristics of temperature inversion that cannot be seen by conventional radiosonde data (twice daily) were obtained by radiometer. This greatly compensates for the limited temporal coverage of radiosonde data. The approach presented by this paper is a valuable reference for the reprocessing of the historical observations, which have been accumulated for years by less-calibrated radiometers.

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Synergistic use of Imager Window observations for Cloud Clearing of Sounder Observation for INSAT-3D

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprsarchives-xl-8-315-2014 ◽

2014 ◽

Vol XL-8 ◽

pp. 315-320 ◽

Cited By ~ 2

Author(s):

J. Satapathy ◽

P. K. Thapliyal ◽

M. V. Shukla ◽

C. M. Kishtawal

Keyword(s):

Statistical Analysis ◽

High Resolution ◽

Spatial Resolution ◽

Atmospheric Temperature ◽

Indian Region ◽

Supplementary Information ◽

Atmospheric Conditions ◽

Clear Sky ◽

Fractional Cloud ◽

Cloud Mask

The retrieval of atmospheric temperature and water vapor profiles from infrared Sounder are severely limited by the presence of cloud. Therefore, retrieval from infrared sounding observations is performed only over clear-sky atmospheric conditions. The probability of finding a clear-sky pixel at spatial resolution of 10 km is found to be very small globally. This study presents a quantitative analysis of the clear-sky probability that is carried out for different months over the Indian region for INSAT-3D Sounder. The probability of a clear-sky is found to be ~7 % for the field of view of 10 km corresponding to the INSAT-3D Sounder. This statistical analysis is established using MODIS cloud mask having 95 % confidence level at 1 km resolution spread in the region between 50E–110E and 30S–30N. This necessitates cloud clearing to remove the effect of partial clouds in the Sounder FOV to provide a clear-sky equivalent sounding retrieval. Various methods were explored to derive the cloud-cleared radiances using supplementary information such as high resolution infrared or microwave observations. This study presents an effort to use the existing traditional method to derive optimal cloudcleared radiances for INSAT-3D Sounder, by estimating the fractional cloud cover using collocated high resolution INSAT-3D Imager window channel observation. The final Sounder cloud-cleared radiances have been validated with the operational AIRS L2 cloud-cleared radiance products. Nevertheless, the statistical analysis of clear-sky probability over Indian region also provides a significant insight towards the dependency of spatial resolution and the considerable field-of-regard (FOR) in obtaining the clear-sky area in the satellite observations. This, in a way, necessitates the cloud-clearing for coarser resolution sensors and at the same time, states the benefits of using very high resolution sensors. It has been observed that FOV of 1km and by choosing a reasonably good FOR can eliminate the cloudy-sky hindrances by increasing the probability of clear-sky from 5 % to 50 %.

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A Global Climatology of Temperature and Water Vapor Variance Scaling from the Atmospheric Infrared Sounder

Journal of Climate ◽

10.1175/2009jcli2934.1 ◽

2009 ◽

Vol 22 (20) ◽

pp. 5558-5576 ◽

Cited By ~ 34

Author(s):

Brian H. Kahn ◽

João Teixeira

Keyword(s):

Boundary Layer ◽

Water Vapor ◽

Seasonal Variations ◽

Atmospheric Infrared Sounder ◽

Upper Troposphere ◽

Clear Sky ◽

Power Law Exponent ◽

Large Length ◽

The Tropics ◽

Scale Break

Abstract A global climatology of height-resolved variance scaling within the troposphere is presented using derived temperature (T) and water vapor (q) profiles from the Atmospheric Infrared Sounder (AIRS). The power-law exponent of T variance scaling approaches 1.0 outside of the tropics at scales >500–800 km, but it is closer to 0.3 at scales <500 km, similar to exponents obtained from aircraft campaigns, numerical modeling, and theoretical studies. The T exponents in the tropics at all scales become less than 0.3, with a similar pattern observed within the boundary layer in some extratropical regions. For q, the variance scaling differs substantially from T with exponents near 0.5–0.6 in parts of the tropics and subtropics with little to no scale break, showing some consistency with a very limited set of aircraft and satellite studies. Scaling differences as a function of land and ocean, altitude, and cloudy- and clear-sky scenes are quantified. Both T and q exponents indicate peak magnitudes in the midtroposphere and reductions are observed near the boundary layer and upper troposphere. Seasonal variations of T and q scaling reveal a stronger seasonal cycle over land than ocean, especially for T at large length scales. While the zonal variations of T and q exponents vary significantly for scales <500 km, the seasonal variations are much smaller in magnitude. The exponents derived from AIRS could eventually be extrapolated to smaller scales in the absence of additional scale breaks <150 km to provide useful information for constraining subgrid-scale cloud parameterizations.

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