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175 Results Found

  • Article
  • Open Access
19 Citations
8,040 Views
30 Pages

3 September 2018

The data assimilation method to improve the sea fog forecast over the Yellow Sea is usually three-dimensional variational assimilation (3DVAR), whereas ensemble Kalman filter (EnKF) has not yet been applied to this weather phenomenon. In this paper,...

  • Article
  • Open Access
240 Views
30 Pages

23 January 2026

Geostationary atmospheric motion vectors (e.g., FY4A AMVs) are routine mid-upper atmospheric observations used in numerical weather prediction (NWP) models, yet their complex spatiotemporal errors and assimilation limitations, i.e., high-temporal/coa...

  • Article
  • Open Access
22 Citations
7,108 Views
20 Pages

A Case Study of Assimilating Lightning-Proxy Relative Humidity with WRF-3DVAR

  • Ying Wang,
  • Yi Yang,
  • Dongxia Liu,
  • Dongbin Zhang,
  • Wen Yao and
  • Chenghai Wang

14 March 2017

Lightning network data, considered as a useful supplement to radar observations, are a good indicator of severe convection, and has high temporal and spatial resolution. In Numerical Weather Prediction (NWP) models, lightning data are a new source of...

  • Article
  • Open Access
31 Citations
4,772 Views
22 Pages

Optimization and Evaluation of SO2 Emissions Based on WRF-Chem and 3DVAR Data Assimilation

  • Yiwen Hu,
  • Zengliang Zang,
  • Dan Chen,
  • Xiaoyan Ma,
  • Yanfei Liang,
  • Wei You,
  • Xiaobin Pan,
  • Liqiong Wang,
  • Daichun Wang and
  • Zhendong Zhang

4 January 2022

Emission inventories are important for modeling studies and policy-making, but the traditional “bottom-up” emission inventories are often outdated with a time lag, mainly due to the lack of accurate and timely statistics. In this study, w...

  • Article
  • Open Access
31 Citations
7,230 Views
17 Pages

21 November 2017

Snow depth is a general input variable in many models of agriculture, hydrology, climate, and ecology. However, there are some uncertainties in the retrieval of snow depth by remote sensing. Errors occurred in snow depth evaluation under the D-InSAR...

  • Feature Paper
  • Article
  • Open Access
12 Citations
5,317 Views
26 Pages

28 April 2023

This study established a WRF/WRF-Hydro coupled forecasting system for precipitation–runoff forecasting in the Daqing River basin in northern China. To fully enhance the forecasting skill of the coupled system, real-time updating was performed f...

  • Technical Note
  • Open Access
10 Citations
2,986 Views
14 Pages

3DVAR Aerosol Data Assimilation and Evaluation Using Surface PM2.5, Himawari-8 AOD and CALIPSO Profile Observations in the North China

  • Zengliang Zang,
  • Wei You,
  • Hancheng Ye,
  • Yanfei Liang,
  • Yi Li,
  • Daichun Wang,
  • Yiwen Hu and
  • Peng Yan

18 August 2022

Based on the Model for Simulating Aerosol Interactions and Chemistry (MOSAIC) aerosol scheme of the Weather Research and Forecasting model coupled with online Chemistry (WRF-Chem) and the three-dimensional variational (3DVAR) assimilation method, a 3...

  • Article
  • Open Access
4 Citations
2,279 Views
14 Pages

In this study, a one-dimensional variational algorithm that combines brightness temperatures (BTs), measured by ocean-based microwave radiometers (MWR), with reanalysis data was developed to generate high accuracy temperature profiles. A forward radi...

  • Article
  • Open Access
18 Citations
3,543 Views
32 Pages

Atmospheric GNSS RO 1D-Var in Use at UCAR: Description and Validation

  • Tae-Kwon Wee,
  • Richard A. Anthes,
  • Douglas C. Hunt,
  • William S. Schreiner and
  • Ying-Hwa Kuo

7 November 2022

This paper describes, along with some validation results, the one-dimensional variational method (1D-Var) that is in use at the University Corporation for Atmospheric Research (UCAR) to retrieve atmospheric profiles of temperature, pressure, and humi...

  • Article
  • Open Access
1,220 Views
19 Pages

To improve the prediction of Typhoon Doksuri (2023), this paper explores how variations in horizontal scale factors used in assimilating radar-derived wind velocities influence the performance of numerical simulations and forecasts. Using the WRF-ARW...

  • Article
  • Open Access
24 Citations
3,821 Views
22 Pages

29 January 2021

In our study, a retrieval method of temperature profiles is proposed which combines an improved one-dimensional variational algorithm (1D-Var) and artificial neural network algorithm (ANN), using FY-4A/GIIRS (Geosynchronous Interferometric Infrared S...

  • Article
  • Open Access
1 Citations
885 Views
22 Pages

30 June 2025

This research investigates how incorporating both radar radial velocity (Vr) and radar reflectivity influences the accuracy of tropical cyclone (TC) prediction. Different control variables are introduced to analyze their roles in Vr data assimilation...

  • Technical Note
  • Open Access
5 Citations
2,398 Views
14 Pages

23 February 2024

This paper presents an innovative approach to enhance the assimilation of high-resolution simulated observations, specifically targeting Surface Water Ocean Topography (SWOT) Ka-band Radar Interferometer Sea Surface Height (SSH) products, within the...

  • Article
  • Open Access
711 Views
20 Pages

Enhancing Forecasting Capabilities Through Data Assimilation: Investigating the Core Role of WRF 4D-Var in Multidimensional Meteorological Fields

  • Yujiayi Deng,
  • Xiaotong Wang,
  • Xinyi Fu,
  • Nian Wang,
  • Hongyuan Yang,
  • Shuhui Zhao,
  • Xiurui Guo,
  • Jianlei Lang,
  • Ying Zhou and
  • Dongsheng Chen

12 November 2025

As climate change intensifies, enhancing numerical weather prediction (NWP) accuracy has been increasingly critical. While data assimilation optimizes NWP initial conditions, its effectiveness over complex terrain requires further systematic evaluati...

  • Article
  • Open Access
2 Citations
3,264 Views
35 Pages

21 April 2023

We previously introduced the parametric variance Kalman filter (PvKF) assimilation as a cost-efficient system to estimate the dynamics of methane analysis concentrations. As an extension of our development, this study demonstrates the linking of PvKF...

  • Communication
  • Open Access
5 Citations
4,223 Views
14 Pages

10 January 2023

The technique of machine learning has been increasingly applied in numerical weather predictions. The aim of this study is to explore the application of a neural network in data assimilation by making use of the convenience in obtaining the tangent l...

  • Article
  • Open Access
37 Citations
4,381 Views
21 Pages

23 April 2019

In this study, the China Hourly Merged Precipitation Analysis (CHMPA) data which combines the satellite-retrieved Climate Prediction Center Morphing (CMORPH) with the automatic weather station precipitation observations is firstly assimilated into th...

  • Technical Note
  • Open Access
3 Citations
2,207 Views
13 Pages

29 December 2022

The launch of the Haiyang-2 (HY-2) satellite constellation fosters the quick acquisition of global sea surface vector winds from the perspective of remote sensing. This study intends to develop a six-hourly mesoscale analysis of sea surface winds bas...

  • Article
  • Open Access
1 Citations
2,630 Views
21 Pages

Evaluation of the 3DVAR Operational Implementation of the Colombian Air Force for Aircraft Operations: A Case Study

  • Jhon Edinson Hinestroza-Ramirez,
  • Juan Ernesto Soto Barbosa,
  • Andrés Yarce Botero,
  • Danilo Andrés Suárez Higuita,
  • Santiago Lopez-Restrepo,
  • Lisseth Milena Cruz Ruiz,
  • Valeria Sólorzano Araque,
  • Andres Céspedes,
  • Sara Lorduy Hernandez and
  • Olga Lucia Quintero
  • + 2 authors

20 July 2023

This manuscript introduces an exploratory case study of the SIMFAC’s (Sistema de Información Meteorológica de la Fuerza Aérea Colombiana) operational implementation of the Weather Research and Forecasting (WRF) model with a...

  • Article
  • Open Access
38 Citations
7,468 Views
25 Pages

22 April 2018

To obtain independent, consecutive, and high-resolution precipitation data, the four-dimensional variational (4D-Var) method was applied to directly assimilate satellite precipitation products into the Weather Research and Forecasting (WRF) model. Th...

  • Article
  • Open Access
16 Citations
5,094 Views
20 Pages

Temperature and Humidity Profiles Retrieval in a Plain Area from Fengyun-3D/HIRAS Sensor Using a 1D-VAR Assimilation Scheme

  • Liuhua Zhu,
  • Yansong Bao,
  • George P. Petropoulos,
  • Peng Zhang,
  • Feng Lu,
  • Qifeng Lu,
  • Ying Wu and
  • Dan Xu

29 January 2020

In this study, a one-dimensional variational (1D-VAR) retrieval system is proposed to simultaneously retrieve temperature and humidity atmospheric profiles under clear-sky conditions. Our technique requires observations from the Fengyun-3D Hyperspect...

  • Article
  • Open Access
3 Citations
4,011 Views
20 Pages

An initial condition that closely represents the true atmospheric state can minimize errors that propagate into the future, and could theoretically lead to improvements in the forecast. This study aims to evaluate and understand the impacts of 3DVAR...

  • Article
  • Open Access
286 Views
28 Pages

5 January 2026

This study developed a multi-source data assimilation system based on the WRF-Chem model integrated with 3DVAR and EAKF methods. By assimilating a multi-source satellite fused XCO2 concentration dataset, the system achieved simultaneous optimization...

  • Article
  • Open Access
10 Citations
3,629 Views
19 Pages

27 May 2021

An attempt was made to evaluate the impact of assimilating Doppler Weather Radar (DWR) reflectivity together with Global Telecommunication System (GTS) data in the three-dimensional variational data assimilation (3DVAR) system of the Weather Research...

  • Article
  • Open Access
2 Citations
3,254 Views
19 Pages

Moisture Recycling over the Iberian Peninsula: The Impact of 3DVAR Data Assimilation

  • Santos J. González-Rojí,
  • Jon Sáenz,
  • Javier Díaz de Argandoña and
  • Gabriel Ibarra-Berastegi

24 December 2019

In this paper, we have estimated the spatiotemporal distribution of moisture recycling over the Iberian Peninsula (IP). The recycling ratio was computed from two simulations over the IP using the Weather Research and Forecasting (WRF) model with a ho...

  • Article
  • Open Access
1 Citations
2,436 Views
16 Pages

Climate change in Thailand is related to the El Niño and Southern Oscillation (ENSO) phenomenon, in particular drought and heavy precipitation. The data assimilation method is used to improve the accuracy of the Ensemble Intermediate Coupled Model (E...

  • Article
  • Open Access
12 Citations
2,764 Views
20 Pages

An Improved Method Combining CNN and 1D-Var for the Retrieval of Atmospheric Humidity Profiles from FY-4A/GIIRS Hyperspectral Data

  • Pengyu Huang,
  • Qiang Guo,
  • Changpei Han,
  • Huangwei Tu,
  • Chunming Zhang,
  • Tianhang Yang and
  • Shuo Huang

23 November 2021

FY-4A/GIIRS (Geosynchronous Interferometric Infrared Sounder) is the first infrared hyperspectral atmospheric vertical detector in geostationary orbit. Compared to other similar instruments, it has the advantages of high temporal resolution and stati...

  • Article
  • Open Access
7 Citations
2,941 Views
23 Pages

14 October 2022

This work investigates extreme weather events such as the onset of medicanes, which can cause severe socioeconomic impacts, along with their predictability. In order to accurately forecast such events, the Weather Research and Forecasting (WRF) model...

  • Article
  • Open Access
2 Citations
4,902 Views
18 Pages

Evaluating the Role of the EOF Analysis in 4DEnVar Methods

  • Xingxia Kou,
  • Zhekun Huang,
  • Hongnian Liu,
  • Meigen Zhang,
  • Si Shen and
  • Zhen Peng

15 August 2017

The four-dimensional variational data assimilation (4DVar) method is one of the most popular techniques used in numerical weather prediction. Nevertheless, the needs of the adjoint model and the linearization of the forecast model largely limit the w...

  • Article
  • Open Access
4 Citations
2,109 Views
16 Pages

22 May 2024

The integration of high-resolution aerosol measurements into an atmospheric chemistry model can improve air quality forecasting. However, traditional data assimilation methods are challenged in effectively incorporating such detailed aerosol informat...

  • Proceeding Paper
  • Open Access
2 Citations
1,897 Views
6 Pages

Data assimilation is a technique used to combine observational data with numerical weather analysis fields to produce input conditions for Numerical Weather Prediction (NWP) models aimed at more accurate forecasts. In this study, two different region...

  • Article
  • Open Access
1 Citations
573 Views
12 Pages

24 April 2025

Temperature and water vapor density profiles in the troposphere (from the surface to 10 km) can be retrieved from a ground-based microwave radiometer (MWR) at high temporal and moderate vertical resolution. The back-propagation neural network (BPNN)...

  • Article
  • Open Access
13 Citations
5,595 Views
27 Pages

3D-VAR Data Assimilation of SEVIRI Radiances for the Prediction of Solar Irradiance in Italy Using WRF Solar Mesoscale Model—Preliminary Results

  • Sabrina Gentile,
  • Francesco Di Paola,
  • Domenico Cimini,
  • Donatello Gallucci,
  • Edoardo Geraldi,
  • Salvatore Larosa,
  • Saverio T. Nilo,
  • Elisabetta Ricciardelli,
  • Ermann Ripepi and
  • Filomena Romano
  • + 1 author

12 March 2020

Solar power generation is highly fluctuating due to its dependence on atmospheric conditions. The integration of this variable resource into the energy supply system requires reliable predictions of the expected power production as a basis for manage...

  • Article
  • Open Access
12 Citations
4,606 Views
45 Pages

Coupled Stratospheric Chemistry–Meteorology Data Assimilation. Part II: Weak and Strong Coupling

  • Richard Ménard,
  • Pierre Gauthier,
  • Yves Rochon,
  • Alain Robichaud,
  • Jean de Grandpré,
  • Yan Yang,
  • Cécilien Charrette and
  • Simon Chabrillat

9 December 2019

We examine data assimilation coupling between meteorology and chemistry in the stratosphere from both weak and strong coupling strategies. The study was performed with the Canadian operational weather prediction Global Environmental Multiscale (GEM)...

  • Article
  • Open Access
7 Citations
4,756 Views
19 Pages

25 September 2017

A hybrid ensemble adjustment Kalman filter—three-dimensional ensemble—variational (EAKF-En3DVar) system is developed to assimilate conventional and radar data, and is applied to a convective case in Colorado and Kansas, USA. The system is based on th...

  • Article
  • Open Access
20 Citations
5,980 Views
19 Pages

5 February 2018

Two remote sensing methods, satellite altimetry and 4D-Var assimilation of satellite imagery, are used to compute surface velocity fields in the Black Sea region. Surface currents derived from the two methods are compared for several cases with inten...

  • Article
  • Open Access
5 Citations
6,103 Views
24 Pages

3 November 2014

This study assesses the analysis performance of a hybrid DEnKF-variational data assimilation (DA) method (DEnVar) for assimilating the MODIS snow cover fraction (SCF) into the Common Land Model (CoLM). Coupling a deterministic ensemble Kalman filter...

  • Article
  • Open Access
8 Citations
3,765 Views
27 Pages

C-Band SAR Winds for Tropical Cyclone Monitoring and Forecast in the South-West Indian Ocean

  • Quoc-Phi Duong,
  • Sébastien Langlade,
  • Christophe Payan,
  • Romain Husson,
  • Alexis Mouche and
  • Sylvie Malardel

29 April 2021

Tropical cyclone (TC) monitoring and forecast in the South West Indian Ocean (SWIO) basin remain challenging, notably because of the lack of direct observations. During the 2018–2019 cyclone season, S-1 Sentinel SAR images were acquired, as part of t...

  • Article
  • Open Access
4 Citations
3,147 Views
24 Pages

A Four Dimensional Variational Data Assimilation Framework for Wind Energy Potential Estimation

  • Elias D. Nino-Ruiz,
  • Juan C. Calabria-Sarmiento,
  • Luis G. Guzman-Reyes and
  • Alvin Henao

5 February 2020

In this paper, we propose a Four-Dimensional Variational (4D-Var) data assimilation framework for wind energy potential estimation. The framework is defined as follows: we choose a numerical model which can provide forecasts of wind speeds then, an e...

  • Article
  • Open Access
8 Citations
2,847 Views
17 Pages

13 January 2023

The advanced imagers onboard the new generation of geostationary satellites could provide multilayer atmospheric moisture information with unprecedented high spatial and temporal resolutions, while the physical retrieval algorithm (One-Dimensional Va...

  • Article
  • Open Access
9 Citations
2,951 Views
21 Pages

16 May 2023

This study explores the impact of assimilating radar radial velocity (RV) on the forecast of Super Typhoon Lekima (2019) using the Weather Research and Forecasting (WRF) model and three-dimensional variational (3DVAR) assimilation system with differe...

  • Article
  • Open Access
13 Citations
4,767 Views
27 Pages

23 November 2018

To compare the effectivenesses of different precipitation datasets on hydrological modelling, five precipitation datasets derived from various approaches were used to simulate a two-week runoff process after a heavy rainfall event in the Wangjiaba (W...

  • Article
  • Open Access
4 Citations
2,667 Views
12 Pages

A Global-Ocean-Data Assimilation for Operational Oceanography

  • Yinghao Qin,
  • Qinglong Yu,
  • Liying Wan,
  • Yang Liu,
  • Huier Mo,
  • Yi Wang,
  • Sujing Meng,
  • Xiangyu Wu,
  • Dandan Sui and
  • Jiping Xie

29 November 2023

In this study, a global-ocean-data-assimilation system based on the three-dimensional variational (3DVAR) scheme is built for operational oceanography. The available observations include satellite altimetry; the satellite-measured sea-surface tempera...

  • Article
  • Open Access
7 Citations
4,422 Views
30 Pages

27 January 2022

Radar data with high spatiotemporal resolution and automatic weather station (AWS) data are used in the data assimilation experiment to improve the precipitation forecast of a numerical model. The numerical model considered in this study is the Weath...

  • Article
  • Open Access
10 Citations
4,757 Views
15 Pages

Satellite Radiance Data Assimilation Using the WRF-3DVAR System for Tropical Storm Dianmu (2021) Forecasts

  • Thippawan Thodsan,
  • Falin Wu,
  • Kritanai Torsri,
  • Efren Martin Alban Cuestas and
  • Gongliu Yang

12 June 2022

This study investigated the impact of the assimilation of satellite radiance observations in a three-dimensional variational data assimilation system (3DVAR) that could improve the tracking and intensity forecasts of the Tropical Storm Dianmu in 2021...

  • Article
  • Open Access
2 Citations
1,299 Views
18 Pages

11 December 2024

Understanding boundary-layer atmospheric temperature and moisture is essential for advancing our knowledge of the Earth system. This study adopts a one-dimensional variational (1DVAR)-based technique to integrate spaceborne measurement and ground-bas...

  • Article
  • Open Access
1,202 Views
18 Pages

Recent advances in high-fidelity modeling, numerical computing, and data science have spurred interest in model-data integration for nuclear reactor applications. While machine learning often prioritizes data-driven predictions, this study focuses on...

  • Article
  • Open Access
21 Citations
7,871 Views
21 Pages

Assimilation of Remotely-Sensed Leaf Area Index into a Dynamic Vegetation Model for Gross Primary Productivity Estimation

  • Rui Ma,
  • Li Zhang,
  • Xiangjun Tian,
  • Jiancai Zhang,
  • Wenping Yuan,
  • Yi Zheng,
  • Xiang Zhao and
  • Tomomichi Kato

23 February 2017

Quantitative estimation of the magnitude and variability of gross primary productivity (GPP) is required to study the carbon cycle of the terrestrial ecosystem. Using ecosystem models and remotely-sensed data is a practical method for accurately esti...

  • Article
  • Open Access
18 Citations
4,920 Views
20 Pages

14 January 2020

Floods caused by heavy rainfall events associated with landfalling tropical cyclones (TCs) represent a major risk for the Yangtze River Delta (YRD) region of China. Accurate extreme precipitation forecasting, at long lead times, is crucial for the im...

  • Article
  • Open Access
9 Citations
3,140 Views
15 Pages

8 May 2020

The module of assimilating a new GMI (GPM Microwave Imager) satellite detector was built in the framework of the Weather Research and Forecasting Model (WRF) and its three-dimensional variational (3DVar) data assimilation system (WRFDA). Typhoon &ldq...

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