THE FIRST JOINT
WCRP-WWRP SYMPOSIUM ON
DATA ASSIMILATION AND REANALYSIS
Programme(4th version, 13 Sep 2021)

Joint WCRP-WWRP Symposium on
Data Assimilation and Reanalysis
in collaboration with the ECMWF Annual Seminar 2021
13 - 17 September 2021 (virtual)organized by

PeopleSteering group

Scientific committee

Wenchao Cao

WMO, Switzerland

Jan Keller, co-chair

DWD / HErZ, Germany

Hilda Carr

ECMWF

Daryl Kleist, co-chair

NOAA, USA

Karen Clarke

ECMWF

Estelle De Coning

WMO, Switzerland

Bodo Ahrens

University of Frankfurt, Germany

Stephen English

ECMWF

Jan Keller, chair

DWD / HErZ, Germany

Daryl Kleist

NOAA, USA

Catherine Michaut

IPSL, FranceMichel Rixen

WCRP, Switzerland

Elisabeth Bauernschubert DWD, Germany
Mike BosilovichNASA, USA

Ivan Bastak DuranUniversity of Frankfurt, Germany

Masatomo Fujiwara

University of Hokkaido, Japan

Hans Hersbach

ECMWF

Lili Lei

Nanjing University, China

Ulrich Löhnert

University of Cologne, Germany

Nabir Mamnun

AWI, Germany

Cory Martin

Redline@NOAA/NCEP, USA

Andy Moore

Univ. of California, Santa Cruz, USA

Deborah Niermann

DWD, Germany

Juan Ruiz

Univ. de Buenos Aires, Argentina

Leonhard Scheck

DWD / HErZ, Germany

Arianna Valmassoi

University of Bonn / HErZ, Germany

Schedule
UTC

9

10

11

12

13

14

15

16

17

PDT

2

3

4

5

6

7

8

9

10

EDT

5

6

7

8

9

10

11

12

13

CEST

11

12

13

14

15

16

17

18

19

JST

18

19

20

21

22

23

0

1

2

O1-1A
DA applications

Monday13 SepOpening talks(room RED)

Get to know
Gather.town

O1-1B
Reanalysis eval.

O1-2
Coupled DA

Poster session
P1

O1-4A
Coupled DA
O1-3
DA platforms

Break

O1-4B
Reanalysis eval.
O1-4C
Hybrid DA

General DA Reanalysis

Tuesday
14 Sep

AS1-2

O2-1A
Operational DA
O2-1B
Reanalysis eval.

O2-2
Operational DA

General DA Reanalysis General DA Reanalysis
AS1-3

Poster session
P2

Methodology

AS2-1

O2-3
Obs. impact

Poster session
P3

Observations

Wednesday
15 SepO3-1A
Atm. compos.
O3-2
DA developments

O2-4C
DA developments

Methodology

AS2-3

O3-1B
DA devel.

AS2-4

Poster session
P3

General DA
AS3-1

Poster session
P4

General DA

O3-3
Ocean DA

Thursday16 SepO4-1A
Atm. compos.

Observations

O4-1C
AeolusO4-2
Global reanalysis
joint session with AS

General DA

Observations

O4-4A
Innovative obs.
O4-3
Regional
reanalysis

AS4-2

Poster session
P5

Friday17 SepO5-1A
Conv. scale DA
O5-1B
Deep learning

O5-2
Deep learning

AS5-1

Methodology

joint session with AS

AS4-4

Poster session
P5

Poster session
P4

Break
O4-4C
Global reanalysis

O5-4A
Conv. scale DA
O5-3
Conv. scale DA

BreakGeneral DA

O4-4B
DA developments

Reanalysis

AS4-3

O5-4B
Obs. impact

Observations

Reanalysis

AS4-5

Poster session
P5

Break

O5-1C
Reg. reanalysis

General DA

Methodology

O5-4C
Reanalysis devel.
General DA

AS5-2

Methodology

AS3-5

Reanalysis

AS4-1

Methodology

Poster session
P3

O3-4C
Non-Gaussian DA
AS3-4

Poster session
P4
Break

O3-4B
Satellites

Methodology

AS3-3

O4-1B
Reg. reanalysis

Observations

Break

O3-1C
G.-bas. rem. sen.
AS3-2

Poster session
P2

AS2-5
O3-4A
Ocean DA

Break
Methodology

O2-4B
Reanalysis eval.
Break

O2-1C
Theoretic. devel.
AS2-2

AS1-4
O2-4A
Operational DA

BreakObservations

Poster session
P1

Break

O1-1C
G.-bas. rem. sen.
AS1-1

Poster session
P2

Poster session
P1

AS5-3

AS5-4

AS5-5

AS5-6

Methodology

Daily schedule
Daily schedule - Monday, 13 Sep 2021
09:00-09:50 Opening Talks, speakers:
room RED
Gerhard Adrian
WMO President
Florence Rabier
ECMWF Director-General
Sarah Jones
DWD Head of Research and Development
Tobias Fuchs
DWD Head of Climate and Environmental Services
Detlef Stammer
Chair of the WCRP Joint Scientific Committee
Jan Keller
Co-chair of WCRP TIRA
Estelle de Coning
Head of WWRP
Daryl Kleist
Co-chair of WWRP DAOS
10:00-11:00 Get to know Gather.Town
UTC
Explore the virtual conference area of the symposium, meetcolleagues and engage in discussions
11:00-11:45 Parallel oral sessionsUTC
DA Applications
Reanalysis evaluation I
Ground-based remote sensing I

room REDroom GREEN
room BLUE

11:45-12:00 Break
12:00-13:00 Plenary oral session
UTC
Coupled DA I

room RED

13:00-14:00 Poster session P1
UTC
General DA
Reanalysis

poster room
Monday14:00-14:45 Plenary oral session
UTC
DA platforms

room RED

14:45-15:00 Break
15:00-16:00 Parallel oral sessions
UTC
Coupled DA II
Reanalysis evaluation II
Hybrid DA

room REDroom GREEN
room BLUE

16:00-18:00 Poster session P1
UTC
General DA
Reanalysis

poster room
MondayDaily schedule
Daily schedule - Tuesday, 14 Sep 2021

Daily schedule - Wednesday, 15 Sep 2021

10:00-11:00 Poster session P2
UTC
Observations
Methodology

poster room
Tuesday

10:00-11:00 Poster session P3
UTC
General DA
Methodology

poster room
Wednesday

11:00-11:45 Parallel oral sessions
UTC
Operational DA I
Reanalysis evaluation III
Theoretical developments in DA

room REDroom GREEN
room BLUE

11:00-11:45 Parallel oral sessions
UTC
DA for atmospheric composition I
DA developments II
Ground-based remote sensing II

room REDroom GREEN
room BLUE

11:45-12:00 Break

11:45-12:00 Break

12:00-13:00 Plenary oral session
UTC
Operational DA II

room RED

12:00-13:00 Plenary oral session
UTC
DA developments III

room RED

poster room
Tuesday

13:00-14:00 Poster session P3
UTC
General DA
Methodology

poster room
Wednesdayroom RED

14:00-14:45 Plenary oral session
UTC
Ocean DA I

room RED

13:00-14:00 Poster session P2
UTC
Observations
Methodology
14:00-14:45 Plenary oral session
UTC
Observation impact
14:45-15:00 Break

14:45-15:00 Break

15:00-16:00 Parallel oral sessions
UTC
Operational DA III
Reanalysis evaluation IV
DA developments I

room REDroom GREEN
room BLUE

15:00-16:00 Parallel oral sessions
UTC
Ocean DA II
Satellites
Non-Gaussian DA

room REDroom GREEN
room BLUE

poster room
Tuesday

16:00-18:00 Poster session P3
UTC
General DA
Methodology

poster room
Wednesday

16:00-18:00 Poster session P1
UTC
Observations
Methodology

Daily schedule
Daily schedule - Thursday, 16 Sep 2021

Daily schedule - Friday, 17 Sep 2021

10:00-11:00 Poster session P4
UTC
Observations
Reanalysis

poster room
Thursday

10:00-11:00 Poster session P5
UTCGeneral DA
Methodology

poster room
Friday11:00-11:45 Parallel oral sessions
UTC
DA for atmospheric composition II
Regional reanalysis I
Aeolusroom REDroom GREEN
room BLUE

11:00-11:45 Parallel oral sessions
UTC
DA on the convective scale I
Deep learning in DA I
Regional reanalysis III

room REDroom GREEN
room BLUE

11:45-12:00 Break

11:45-12:00 Break

12:00-13:00 Plenary oral session
UTC
Global reanalysis I
room RED(joint session with ECMWF Annual Seminar)

12:00-13:00 Plenary oral session
UTC
Deep learning in DA II

room RED

13:00-14:00 Poster session P5
UTCGeneral DA
Methodology

poster room
Friday14:00-14:45 Plenary oral session
UTC
DA on the convective scale II

room RED

13:00-14:00 Poster session P4
UTC
Observations
Reanalysis
14:00-14:45 Plenary oral session
UTC
Regional reanalysis II

poster room
Thursdayroom RED

14:45-15:00 Break
15:00-16:00 Parallel oral sessions
UTC
Innovative observations
room REDDA developments IV
room GREEN
Global reanalysis II
room BLUE(joint session with ECMWF Annual Seminar)
16:00-18:00 Poster session P4
UTC
Observations
Reanalysis

poster room
Thursday

14:45-15:00 Break
15:00-16:00 Parallel oral sessions
UTC
DA on the convective scale III
Observation impact II
Reanalysis development

room REDroom GREEN
room BLUE

16:00-18:00 Poster session P5
UTCGeneral DA
Methodology

poster room
FridayOral sessions
Additional information on sessions:Talks: Oral sessions have either 3 or 4 slots with 15 minutes (12+3) per talk.
Posters: Each poster session has an allocated time of three hours which is distributed over one day. Each poster session contains
contributions from two of the major topics.
General DA

Methodology

Operational DA
O2-1A, O2-2, O2-4A

DA developments
O2-4C, O3-1B, O3-2, O4-4B

Ocean DAO3-3, O3-4A

Non-Gaussian DA
O3-4C

DA on the convective scale
O5-1A, O5-3, O5-4A

Hybrid DA
O1-4C

DA applications
O1-1A

Coupled DA
O1-2, O1-4A

DA platforms
O1-3

Theoretical developments in DA
O2-1C

DA for atmospheric composition
O3-1A, O4-1A

Deep Learning in DA
O5-1B, O5-2

Observations

Reanalysis

Observation impact
O2-3, O5-4B

Global Reanalysis
O4-2, O4-4C (joint sessions with ECMWF Annual Seminar)

Satellites
O3-4B

Regional Reanalysis
O4-1B, O4-3, O5-1C

Ground-based remote sensing
O1-1C, O3-1C

Reanalysis developments
O5-4C

AeolusO4-1C

Reanalysis evaluation
O1-1B, O1-4B, O2-1B, O2-4B

Innovative observations
O4-4A

Oral sessions
DA applications (O1-1A)
Monday, 13 Sep 2021 - room RED

General DA
chair: J. Ruiz, D. Kleist

11:00 UTC

Avinash Parde

Impact of high-resolution land surface data assimilation on fog: A case study from the WiFEX campaign

11:15 UTC

Mélanie Rochoux

Data assimilation for landscape-scale wildland fire behavior

11:30 UTC

Arianna Valmassoi

Data Assimilation on the Sub-Kilometer Scale for the Urban Environment

Reanalysis evaluation I (O1-1B)
Monday, 13 Sep 2021 - room GREEN

Reanalysis
chair: I. Bastak Duran, D. Niermann

11:00 UTC

Masatomo Fujiwara

Overview of the SPARC Reanalysis Intercomparison Project (S-RIP) during 2013-2021

11:15 UTC

Andrea Storto

The 20th century global warming signature on the ocean at global and basin scales as depicted from historical reanalyses

11:30 UTC

Yuki Kosaka

Representation of the past weather prior to the International Geophysical Year (1957-1958) in JRA-3Q

Ground-based remote sensing I (O1-1C)
Monday, 13 Sep 2021 - room BLUE

Observations
chair: L. Scheck, S. Dance

11:00 UTC

Ullrich Löhnert

Ground-based atmospheric boundary layer profiling and data assimilation experiments within the EU COST Action PROBE

11:15 UTC

Claire Merker

Towards operational assimilation of surface based microwave radiometer and Raman lidar data at MeteoSwiss

11:30 UTC

Donald Lippi

Doppler radial wind assimilation in the GFS with an observing system simulation experimentOral sessions
Coupled DA I (O1-2)
Monday, 13 Sep 2021 - room RED

Methodology
chair: A. Valmassoi, D. Kleist

12:00 UTC

Yonghong Yin

Development of Coupled Data Assimilation for the Bureau of Meteorology's Operational Climate Forecast System ACCESS–S

12:15 UTC

Tsz Yan Leung

The impact of incorporating flow-dependent oceanic background-error covariance information into air-sea coupled data assimilation on theevolution of a tropical cyclone

12:30 UTC

Qi Tang

Weakly and strongly coupled data assimilation with the coupled ocean-atmosphere model AWI-CM

12:45 UTC

Polly Smith

Incorporating flow dependent ocean information into weakly coupled atmosphere-ocean 4D-Var data assimilation: experiments with an
idealised system

Oral sessions
DA platforms (O1-3)
Monday, 13 Sep 2021 - room RED

General DA
chair: J. Keller, A. Valmassoi

14:00 UTC

Lars Nerger

PDAF - features and recent developments

14:15 UTCTom Auligne

JCSDA's vision of a community data assimilation for research and operations

14:30 UTC

Kevin Raeder

A CESM+DART Atmospheric Reanalysis for Forcing Ocean, Land, and Other Surface Models.

Oral sessions
Coupled DA II (O1-4A)
Monday, 13 Sep 2021 - room RED

Methodology
chair: A. Valmassoi, N. Mamnun

15:00 UTC

Gregory Hakim

Skillful Coupled Atmosphere-Ocean Data Assimilation - on a Laptop

15:15 UTC

Sebastian Massart

Skin temperature analysis used for the assimilation of clear-sky radiances

15:30 UTCClara Draper

Modernising the Land Data Assimilation and Land Model Uncertainty Estimation in NOAA's Global NWP Systems

15:45 UTC

Dave Turner

Improved Understanding of Land-Atmosphere Interactions Using Profiling and Surface Flux Observations

Reanalysis evaluation II (O1-4B)
Monday, 13 Sep 2021 - room GREEN

Reanalysis
chair: J. Keller, M. Fujiwara

15:00 UTC

Mike Bosilovich

Overview of MERRA-2 for Applications, Decision-making, and Climate Assessment

15:15 UTC

Natalie Thomas

Mechanisms Associated with Daytime and Nighttime Heat Waves over the Contiguous United States

15:30 UTC

Michal Kozubek

Detail Analysis Of Stratospheric Trends Using ERA5

15:45 UTC

Nedjeljka Žagar

Tropical wave analyses: variability, trends and uncertainties in ERA-Interim, JRA-55, MERRA and ERA5 reanalyses

Hybrid DA (O1-4C)
Monday, 13 Sep 2021 - room BLUE

Methodology
chair: A. Moore, B. Ahrens

15:00 UTC

Loik Berre

4D-hybrid formulation of 4DEnVar for global data assimilation at Météo-France

15:15 UTC

Michael Tsyrulnikov

Ensemble-variational assimilation with constrained non-stationary spatial convolutions

15:30 UTC

Lili Lei

Integrated Hybrid Data Assimilation for an Ensemble Kalman Filter

15:45 UTC

Ting Lei

Tests of hybrid EnKF-Variational Data Assimilation capabilities using JEDI with NOAA's Next Generation Regional High Resolution NWP
SystemOral sessions

Oral sessions
Operational DA I (O2-1A)
Tuesday, 14 Sep 2021 - room RED

General DA
chair: C. Martin, S. Polavarapu

11:00 UTC

M. Krysta

National Analysis System

11:15 UTCY. Ikuta

New Variational Data Assimilation System for Regional Model at JMA

11:30 UTC

M. Hu

Building a JEDI- and FV3-based Rapid Refresh Forecast System (RRFS) upon Decade of Development and Implementation of the High
Resolution Rapid Refresh (HRRR)

Reanalysis evaluation III (O2-1B)
Tuesday, 14 Sep 2021 - room GREEN

Reanalysis
chair: M. Fujiwara, D. Niermann

11:00 UTC

C. Kobayashi

Brewer-Dobson circulation represented in JRA-3Q

11:15 UTC

Z. Heyvaert

Comparison of land surface data assimilation results driven by MERRA-2 and ERA5 meteorological forcings

11:30 UTC

N. Fourrie

Data assimilation impact studies with the AROME-WMED reanalysis during HyMeX SOP1

Theoretical Developments in DA (O2-1C)
Tuesday, 14 Sep 2021 - room BLUE

Methodology
chair: L. Lei, T. Auligne

11:00 UTC

C. SnyderAn optimal linear transformation for data assimilation

11:15 UTCG. Hu

A Numerical Approximation Method for Fast Computations of Matrix-Vector Products with Spatially Correlated Observation Error Statistics

11:30 UTC

I. Dauzickaite

Randomised preconditioning in variational data assimilation

Oral sessions
Operational DA II (O2-2)
Tuesday, 14 Sep 2021 - room RED

General DA
chair: E. Bauernschubert, T. Auligne

12:00 UTC

D. Kleist

NCEP Operational Global Data Assimilation System (GDAS): Recent Upgrades and Future Plans

12:15 UTC

R. Potthast

The Global-to-Regional Data Assimilation System for the ICON Model

12:30 UTC

M. Bonavita

Advancing Data Assimilation in Global NWP and Climate: the ECMWF Perspective

12:45 UTC

I.-H. Kwon

Status and Plans of Data Assimilation at KIAPSOral sessions
Observation Impact I (O2-3)
Tuesday, 14 Sep 2021 - room RED

Observations
chair: U. Löhnert, I. Bastak Duran

14:00 UTC

B. Ingleby

Aircraft data and Covid-19: impact and mitigation measures at ECMWF

14:15 UTC

T. Nomokonova

Estimation of the benefits of remote-sensing profilers for sustainable energy applications

14:30 UTC

A. Yamazaki

EFSO at different geographical locations verified with observing system experiments

Oral sessions
Operational DA III (O2-4A)
Tuesday, 14 Sep 2021 - room RED

General DA
chair: U. Löhnert, N. Mamnun

15:00 UTCR. Gelaro

The JEDI-GEOS application: NASA's development pathway for coupled Earth system data assimilation

15:15 UTC

J. Carley

Data Assimilation for NOAA's Next Generation Regional High Resolution NWP System

15:30 UTC

C. Martin

Initial Evaluation of JEDI Unified Forward Operator For Use in NCEP's Global Data Assimilation System

15:45 UTC

L. Slivinski

Progress towards a global hourly-updating data assimilation system

Reanalysis evaluation IV (O2-4B)
Tuesday, 14 Sep 2021 - room GREEN

Reanalysis
chair: I. Bastak Duran, H. Hersbach

15:00 UTC

M. Marosz

Daily extreme temperatures in ERA5-LAND versus in-situ measurements in Poland 1991-2020

15:15 UTC

M. Mytilinaios

Evaluation of a high-resolution dust regional reanalysis using in-situ and remote sensing observations

15:30 UTC

K. Kosovelj

Comparison of a Multidecadal Walker Circulation in European reanalyses

15:45 UTC

B. SaraOperating in risky sand and dust storm environments in Northern Africa, the Middle East and Europe: a portfolio of climate services

New approaches to DA I (O2-4C)
Tuesday, 14 Sep 2021 - room BLUE

Methodology
chair: A. Moore, B. Ahrens

15:00 UTC

J. Anderson

A General Ensemble Filtering Framework Using Quantiles

15:15 UTC

X. Wang

A new multiscale data assimilation method: Multiscale Local Gain Form Ensemble Transform Kalman Filter (MLGETKF)

15:30 UTC

R.S. Consuegra Ortega

Operational Data Assimilation using the Ensemble Kalman Filter with a Modified Cholesky decomposition

15:45 UTC

D. Daescu

Adaptive Tuning of Innovation Weight Parameters: Formulation and Results with NAVDAS-AR/NAVGEM

Oral sessions

Oral sessions
DA for atmospheric composition I (O3-1A)
Wednesday, 15 Sep 2021 - room RED

General DA
chair: C. Martin, S. Polavarapu

11:00 UTC

E. Di Tomaso

A novel regional reanalysis of dust aerosols

11:15 UTCP. Rawat

Radiance intercalibration of INSAT-3D ozone channel with MSG-SEVIRI and successive improvements in ozone optimal/ML retrieval andvalidations

11:30 UTC

B. Huang

Development of an Ensemble-Variational Data Assimilation System for Global Aerosol Forecasting at NOAA

New approaches to DA II (O3-1B)
Wednesday, 15 Sep 2021 - room GREEN

Methodology
chair: E. Bauernschubert, B. Ahrens

11:00 UTC

D. Francis

The Effective Use of Anchor Observations in VarBC in the Presence of Model Bias

11:15 UTC

O. Stiller

Newly developed impact diagnostics for cross-validating the consistent use of different observation types

11:30 UTC

M. Bocquet

State, global and local parameter estimation using ensemble Kalman filters for model error correction

Ground-based remote sensing II (O3-1C)
Wednesday, 15 Sep 2021 - room BLUE

Observations
chair: I. Bastak Duran, S. Healy

11:00 UTC

M. Kayser

Long-term assessment of Doppler lidars for an operational use in a future network

11:15 UTC

C. Knist

Assessment of microwave radiometers for operational network deployment and its observational value for forecasting models

11:30 UTC

A. Bell

Expected Benefit of Cloud Radar and Microwave Radiometer Observations for Future Data Assimilation During Fog Conditions

Oral sessions
New approaches to DA III (O3-2)
Wednesday, 15 Sep 2021 - room RED

Methodology
chair: J. Ruiz, B. Ahrens

12:00 UTC

O. PannekouckeContributions of the parametric Kalman filter in practical and theoretical data assimilation

12:15 UTC

K. Lonitz

What does the spread amongst ensembles tell us about forecast errors?

12:30 UTC

D. Hotta"Twin-analysis" verification: a new verification approach that alleviates pitfalls of "own-analysis" verification when applied to short-range
forecasts

12:45 UTC

M. Buehner

Local Ensemble Transform Kalman Filter with Cross-Validation

Oral sessions
Ocean DA I (O3-3)
Wednesday, 15 Sep 2021 - room RED

General DA
chair: N. Mamnun, T. Auligne

14:00 UTC

D. LeaA new global ocean ensemble system at the Met Office: Assessing the impact of hybrid data assimilation and inflation settings

14:15 UTCP. Heimbach

Quantitative Observing System Design within ECCO's 4DVar ocean data assimilation framework

14:30 UTC

A. Moore

Forecast Sensitivity to Observations in an Analysis-Forecast System of the California Current Circulation

Oral sessions
Ocean DA II (O3-4A)
Wednesday, 15 Sep 2021 - room RED

General DA
chair: A. Moore, N. Mamnun

15:00 UTC

I. Fenty

The Estimating the Circulation and Climate of the Ocean (ECCO) “Central Estimate”: a Multi-decadal, Coupled Ocean Reanalysis

15:15 UTC

M. Martin

Assimilation of satellite total surface current velocities in global ocean forecasting systems

15:30 UTC

L. LiuImpact of superobbing high resolution marine glider and HF radar data in regional marine JEDI data assimilation system

Satellites (O3-4B)
Wednesday, 15 Sep 2021 - room GREEN

Observations
chair: U. Löhnert, L. Lei

15:00 UTC

S. LeeAll-sky microwave humidity sounder assimilation in the Korean Integrated Model forecast system

15:15 UTC

W. HanEvaluation and Assimilation of Geostationary Hyperspectral InfraRed Sounders (GeoHIS) : Progress and Challenges

15:30 UTC

L. Scheck

Improving cloud and radiation forecasts by assimilating visible satellite images

15:45 UTC

P. Combarnous

An observation operator for geostationary lightning imager data assimilation in storm-scale numerical weather prediction systems

Non-Gaussian DA (O3-4C)
Wednesday, 15 Sep 2021 - room BLUE

Methodology
chair: J. Ruiz, B. Ahrens

15:00 UTC

N. Schenk

4D-Localized Particle Filter Method in KENDA for ICON-LAM

15:15 UTC

S. Kotsuki

Improving the stability of the Local Particle Filter and Its Gaussian Mixture Extension: Experiments with an Intermediate AGCM

15:30 UTC

C.-C. Hu

A new way to infer non-Gaussian observation errors based on ensemble innovations

15:45 UTC

S. Fletcher

Non-Gaussian Hybrid Variational Data Assimilation

Oral sessions

Oral sessions
DA for atmospheric composition II (O4-1A)
Thursday, 16 Sep 2021 - room RED

General DA
chair: L. Scheck, C. Martin

11:00 UTC

A. Tsikerdekis

Aerosol data assimilation as a tool to detect model errors

11:15 UTC

H. Wang

Assimilation of Aerosol Optical Depth (AOD) retrievals and PM2.5 in NCEP's Next-Generation Regional Air Quality Forecasting System

Regional reanalysis I (O4-1B)
Thursday, 16 Sep 2021 - room GREEN
11:00 UTC

A. Aydogdu

A high resolution reanalysis for the Mediterranean Sea

11:15 UTC

I. Rani

IMDAA regional reanalysis over the Indian monsoon region

11:30 UTC

S. Fukui

Performance of a 5-km regional reanalysis over Japan with respect to summer precipitation

Aeolus (O4-1C)
Thursday, 16 Sep 2021 - room BLUE

Reanalysis
chair: J. Keller, D. Niermann

Observations
chair: U. Löhnert, N. Fourrier

11:00 UTC

A. Cress

Validation and Impact assessment of Aeolus Doppler Wind Lidar Observations at the German Weather Service

11:15 UTC

K. IdeImpact Assessment of Aeolus Wind on NOAA Global NWP Analyses and Forecasts

11:30 UTC

C. Chou Chih

Validation of Aeolus L2B Wind Product with ECCC Short-Range Forecasts and ERA5 over the Arctic

Oral sessions
Global reanalysis I (O4-2)
Thursday, 16 Sep 2021 - room RED

Reanalysis
chair: J. Keller, M. Fujiwara

12:00 UTC

S. Kobayashi

JRA-3Q: Japanese Reanalysis for Three Quarters of a Century

12:30 UTC

H. Hersbach

The ERA5 reanalysis: a detailed record of the climate and weather for the past 70 years.

12:45 UTC

L. Slivinski

A synoptic to decadal evaluation of the 20th Century Reanalysis Version 3

Oral sessions

Oral sessions
Regional reanalysis II (O4-3)
Thursday, 16 Sep 2021 - room RED

Reanalysis
chair: I. Bastak Duran, H. Hersbach

14:00 UTCF. Kaspar

Regional reanalysis activities at DWD: review and outlook

14:15 UTC

S. Schimanke

Copernicus European regional reanalysis

14:30 UTC

H. Schyberg

The Copernicus Arctic Regional Reanalysis

Oral sessions
Innovative observations (O4-4A)
Thursday, 16 Sep 2021 - room RED

Observations
chair: E. Bauernschubert, N. Mamnun

15:00 UTC

W. Acevedo

Usage of crowd-sourced meteorological car data for new real time road weather forecast

15:15 UTC

A. Kelbch

The potential of assimilating wind power data for future reanalysis

15:30 UTC

Z. Paschalidi

Assimilation of surface observations from citizen weather stations into a regional weather prediction system

15:45 UTC

S. Dance

Exploring the characteristics of a vehicle-based temperature dataset for convection-permitting numerical weather prediction

New approaches to DA IV (O4-4B)
Thursday, 16 Sep 2021 - room GREEN
15:00 UTC

I. Moradi

Assimilation of microwave radiances over the rainbands of tropical cyclones

15:15 UTC

X. Su

Hilbert curves for data thinning and application to aircraft data

15:30 UTC

D. Holdaway

Evaluation of background error models for JEDI-based data assimilation with GFS and GEOS.

15:45 UTC

F. Fabry

Are we minimizing the appropriate errors in data assimilation for weather forecasting?

Global reanalysis II (O4-4C)
Thursday, 16 Sep 2021 - room BLUE

Methodology
chair: L. Scheck, J. Ruiz

Reanalysis
chair: M. Bosilovich, B. Ahrens

15:00 UTCJ. Munoz-Sabater

The ERA5-Land Global land surface reanalysis

15:15 UTC

W. Bell

Preparations for assimilating rescued and reprocessed satellite sounding observations in the next generation global atmospheric reanalysis
at ECMWF - ERA6

15:30 UTC

A. El Akkraoui

The NASA GMAO retrospective analysis for the 21st Century GEOS-R21C

15:45 UTC

D.S. Banerjee

The CMCC Global Ocean Reanalysis System (C-GLORS): a series of consolidated eddy-permitting ocean reanalyses

Oral sessions
Convective scale DA I (O5-1A)
Friday, 17 Sep 2021 - room RED

General DA
chair: A. Valmassoi, E. Bauernschubert

11:00 UTCT. Janjic

Representation of model error in convective scale data assimilation

11:15 UTCL. Neef

Assimilation of Nowcast Objects in the Regional Forecast Model ICON-LAM

11:30 UTC

L. DucComparison of 4D-EnVAR and 4D-LETKF when running with 1000 ensemble members

Deep learning in DA I (O5-1B)
Friday, 17 Sep 2021 - room GREEN

Methodology
chair: J. Keller, J. Ruiz

11:00 UTC

A. Farchi

Model error correction with data assimilation and machine learning

11:15 UTC

B. Sébastienhigh-resolution Ensemble Kalman Filter with a low-resolution model using a machine learning super-resolution approach

11:30 UTCY. Wang

Deep-Learning Augmented Data Assimilation: Reconstructing Missing Information With Convolutional Autoencoders

Regional reanalysis III (O5-1C)
Friday, 17 Sep 2021 - room BLUE

Reanalysis
chair: H. Hersbach, N. Mamnun

11:00 UTC

A. El-Said

A new temporally flow-dependent EDA to estimate B-matrix in Copernicus European Regional Reanalysis

11:15 UTC

S.R. Sanikommu

A 20-year High resolution Red Sea Reanalysis using a Hybrid ensemble data assimilation

11:30 UTC

P. Franke

Evaluation of European anthropogenic trace gas and aerosol emissions using 4D-var: First results of a full-year re-analysis for 2016

Oral sessions
Deep learning in DA II (O5-2)
Friday, 17 Sep 2021 - room RED

Methodology
chair: L. Scheck, U. Löhnert

12:00 UTC

S. Legler

Combining Data Assimilation and Machine Learning to Estimate Parameters of a Convective-Scale Model

12:15 UTC

A. Popov

Surrogate Tree and Model Forest Extensions to the Multifidelity Ensemble Kalman Filter

12:30 UTC

F.J. Acevedo García

Data-Driven Methods for Weather Forecast

12:45 UTC

T.-C. Chen

Learning UFS State-Dependent Systematic Errors from the Analysis Increments

Oral sessions

Oral sessions
Convective scale DA II (O5-3)
Friday, 17 Sep 2021 - room RED

General DA
chair: J. Keller, E. Bauernschubert

14:00 UTC

T. Miyoshi

Big Data Assimilation: Real-time Demonstration Experiments of 30-second-update Forecasting in Tokyo in 2020 and 2021

14:15 UTC

J. Waller

Evaluating errors due to unresolved scales in convection permitting numerical weather prediction

14:30 UTC

T. Necker

Localization on convective scales: What can we learn from a 1000-member ensemble?

Oral sessions
Convective scale DA III (O5-4A)
Friday, 17 Sep 2021 - room RED

General DA
chair: L. Scheck, L. Lei

15:00 UTCY. Wang

Further development of simultaneous multiscale data assimilation in EnVar to improve convective scale weather prediction

15:15 UTC

C. Schwartz

Experiments with a continuously cycling 3-km ensemble Kalman filter over the entire conterminous United States for convection-allowing
ensemble initialization

15:30 UTC

J. Ruiz

Reduced non-Gaussianity by 30-second rapid update in convective-scale numerical weather prediction

15:45 UTC

J. Sodhi

Large error correction in storms at convective scales by “grafting” look-alike modelled storms from other ensemble backgrounds

Observation Impact II (O5-4B)
Friday, 17 Sep 2021 - room GREEN

Observations
chair: C. Martin, U. Löhnert

15:00 UTC

C.-C. Chang

Implementation of Ensemble Forecast Sensitivity to Observations (EFSO) on a operational-like CFSv2 model and modifications forreanalysis

15:15 UTC

R. Todling

Impact of Losing Aqua and Legacy POES and of Gaining Radio-Occultation Observations

15:30 UTCY. ZhuAssessment of observation impact on the low troposphere in the GMAO GEOS system

15:45 UTC

M. Zheng

Impact of Dropsondes from the Atmospheric River (AR) Reconnaissance Program on Forecast Skill of ARs and the Satellite Radiance
Assimilation

Reanalysis development (O5-4C)
Friday, 17 Sep 2021 - room BLUE

Reanalysis
chair: M. Bosilovich, H. Hersbach

15:00 UTC

S. Rennie

Towards an enhanced regional atmospheric reanalysis for Australia

15:15 UTC

M. Pagowski

Developing Aerosol Reanalysis at NOAA Version 1.0: Methodology and Results

15:30 UTC

X. Yang

Development of kilometer scale regional data assimilation for Copernicus Arctic Regional Reanalysis

15:45 UTC

S. Wahl

A novel approach to surface reanalysis

Poster sessions
P1 - Monday, 13 Sep 2021 (13:00-14:00, 16:00-18:00)
General DA

Reanalysis

D. Carneiro

Improving Met Office predictions of Artic sea ice through assimilation of
CryoSat-2 and SMOS thickness data

A. ArshadSPI-based drought forecasting data assimilation by using ARIMA models

T. DiefenbachPartial analysis increments as diagnostic for LETKF data assimilation systems

S. BalExamining the model parameters of COSMO-CLM in 11 selected extreme
events over West Bengal (WB), India

L. DucInvestigation of the potential factors that caused the July 2020 Kyushu heavy
rain using a 1000-member ensemble simulation

M. Bosilovich

Regional Water Cycle Consistency in Atmospheric Reanalysis

C. Gas

Evaluating block methods for Ensemble Data Assimilation in JEDI

R. Balmaceda-Huarte

Evaluation of multiple reanalyses in reproducing temperature andprecipitation indices over southern South America

I. Hernandez Banos

Test and evaluation of data assimilation algorithms and configurations toimprove the Rapid Refresh Forecast System for convection forecasts
Ensemble Data Assimilation and Probabilistic Forecast with 1000 Members
Coupled with a Hydrological Model Using the Supercomputer “Fugaku” Aiming
to the Impact-Based Forecast

A. Cipollone

Assimilation strategies of sea-ice remotely-sensed observations for ocean
Reanalysis

M. Morris

Using reanalysis to assess ‘design-level’ wind events with the potential for
infrastructure damage in the built environment

N. Kutaladze

WRF- 3DVAR application for Georgia

D. Niermann

Evaluating extreme wind speed in regional and global reanalysis products

H.-N. Kwon

The enhancement of usage of the aircraft based observations in the KIAPS
data assimilation system

P.K. Pothapakula

Exploring Information Exchange in Climate System Applications.

S. LiuComparison of JEDI Unified Forward Operator and GSI Observer Using Rapid
Refresh Forecast System Background

J. Stoyanova

Use of remote sensing retrievals of evapotranspiration based on reanalysis
data for assessment of forested landscape drying

R. Menard

The WMO Global Air Quality Forecast and Information System (GAFIS) project

N. Thomas

Regionalization of MERRA-2 50-m wind speed over the United States forEnergy Applications

L. Mona

ACTRIS/EARLINET pilot for nrt provision of aerosol remote sensing profiles to
cams

T. Spangehl

Usage of reanalysis data for wind energy expansion in the North Sea andBaltic Sea

E. Satterfield

An Overview of Atmospheric Data Assimilation at the Naval ResearchLaboratory

H. ShaoDeveloping Unified Forward Operator (UFO) for JEDI at the Joint Center for
Satellite Data Assimilation (JCSDA)

X. Su

New Variational Quality Control scheme and application in GSI

X. Zhang

Satellite radiance data assimilation within NOAA's prototype Rapid Refresh
Forecast System

T. Kawabata

all times are in UTC

Poster sessions
P2 - Tuesday, 14 Sep 2021 (10:00-11:00, 13:00-14:00, 16:00-17:00)
Methodology

Observations

N. Baillot D'etivaux

Breakdown of the equivalence between two common preconditionnings in
multi-incremental variational data assimilation

J. Amezcua

Assimilating atmospheric infrasound data to constrain atmospheric winds
in a two-dimensional grid

K. Bhargava

Impact of assimilating SST vs nudging in an atmosphere ocean coupled
model

B. Balan-Sarojini

Impact of Ocean Observations on ECMWF Extended-Range Forecasts

C. Da

Multi-layer Observation Localization for Nonlocal Observations in the
LETKF

J. Carley

Assimilation of Web Camera Derived Estimates of Horizontal Visibility

J. Dong

G. Casaretto

Ensemble Forecast Sensitivity to Observations applied to a regional data
assimilation system over Argentina

T. Chen

Assimilating Disorganized Crowdsourced Imagery Data for Machine
Learning-based Geomorphological Change Detection Research

T. Gichamo

JEDI application in Assimilation and Evaluation of GTS Synoptic Snow
Depth Observations into NCEP Operational FV3GFS System
A Comparison of Two Local Moment-Matching Nonlinear Filters: Local
Particle Filter (LPF) and Local Nonlinear Ensemble Transform Filter(LNETF)
Updating and Testing the Snow Data Assimilation in the Unified Forecast
System (UFS) Land surface model NoahF. Diniz

Deriving observation impact measures through the FV3-JEDI interface

S. Gilpin

Continuum Covariance Propagation for Understanding Variance Loss in
Advective Systems

I. Genkova

Status of Atmospheric Motion Vectors use in the NCEP GFS data
assimilation system

T. Kawabata

An Adaptive R Estimator with a Storm-Scale Particle Filter

B. Ingleby

Estimates of radiosonde impact and their implications

S. Kotsuki

Local Ensemble Transform Kalman Filter Experiments with Hybrid
Background Error Covariance: A Case with an Intermediate AGCM

H.-B. Jeong

Assimilation of GK-2A clear sky radiance products in the KIM DA system

R. Menard

Numerical discretization causing error variance loss and the need for
inflation

H.-C. Lee

An Evaluation for Impacts of Ocean Observing System in the NCEP
GODAS

S. Nakashita

Assimilation of Nonlinear Observations with the Maximum Likelihood
Ensemble Filter

X. Li

Sea Surface Temperature analysis within the NCEP GFS

L. Nerger

L. Pires

Observing System Simulation Experiments in the Brazil Current using
SWOT synthetic data with HYCOM+RODAS

D. Risto

R. Reichle

A hybrid nonlinear-Kalman ensemble transform filter for data assimilationin systems with different degrees of nonlinearity
CAFE60v1: The CSIRO Climate retrospective Analysis and Forecast
Ensemble system: version 1: System design, model configuration and data
assimilation.
Assimilation of SMAP Brightness Temperature Observations in the GEOS
Land-Atmosphere Data Assimilation System

S. Scherrer

Towards the assimilation of microwave vegetation optical depth into global
land surface models

F. Vandenberghe

Influence of Snow Representation in Operational Seasonal Prediction
Systems
A virtual network of ground-based microwave radiometers for monitoring of
atmospheric stability and its potential impact in synergy with hyperspectral
satellite observations.
Estimating the impact of commercial observations with an Ensemble ofData Assimilations approach

A. Subrahmanya

A variational particle filter

X. Wu

Impact of Aircraft High-Density Observations on GFSv16 Tropical Cyclone
Forecasts

Y. Zeng

Interpreting estimated Observation Error Statistics of Weather Radar
Measurements using the ICON-LAM-KENDA System

J. Feng

T. O'kane

all times are in UTC

M. Toporov

Poster sessions
P3 - Wednesday, 15 Sep 2021 (10:00-11:00, 13:00-14:00, 16:00-17:00)
General DA

Methodology
Reconstructing the dynamics of the outer electron radiation belt by meansof the standard and ensemble Kalman filter with the VERB-3D code
Online nonlinear bias correction in ensemble Kalman filter to assimilate
GOES-R all-sky radiances for the analysis and prediction of rapidly
developing supercells
Assimilating various environmental features to train machine learningalgorithms for sea ice drift prediction in the Arctic as a key geophysicalparameter for understanding climate change
Improving Tropical Cyclone Predictions by Assimilation of SatelliteRetrieved Surface Precipitation with Gaussian Transformation
Evaluation of Observation Impact and Low-Skill Forecasts in the NCEP
Global Forecast System/Global Data Assimilation System using Ensemble
Forecast Sensitivity to Observation Impact

C. Book

High-Resolution Regional Ocean Data Assimilation in JEDI-SOCA
framework: Hurricane Supplemental Project at NOAA-EMC

A. Castillo

I. Fukumori

Studying Causal Mechanisms of the Ocean with the ECCO Estimate:
Beaufort Sea Sea-Level and Freshwater-Content Change

K. Chandramouli

A. Galodha

Impact of COVID-19 measures on the air quality, monitored for the state of
Himachal Pradesh: A Google Earth Engine Based Study

T. ChenD. Halpern

Evaluation of ECCO Currents in the Pacific Equatorial Undercurrent

C. Da

M. Khoshsima

Atmospheric radiance variation: On the basis of atmospheric aerosols in
different locations IranA. Eichmann

C. Martin

Assimilating TROPOMI Nitrogen Dioxide Retrievals in NOAA's NextGeneration Regional Air Quality Forecasting System

T. Enomoto

Maximum Likelihood Ensemble Filter with Exact Newton Optimization

H. Pohlmann

Ocean data assimilation for ICON-Seamless

S. Frolov

Local volume solver with the static covariance model: LETKF-OI

S. Sabetghadam

Validation of MODIS, MISR and OMI aerosol optical depth with globally
distributed AERONET data over the Middle East region

T. Ishibashi

Improvement of Accuracy of Global Numerical Weather Prediction Using
Refined Error Covariance Matrices

R. Santana

Mesoscale and wind‚Äëdriven intra‚Äëannual variability in the East
Auckland Current

T. KojiIncluding the spatial observation error correlation in data assimilation of
AMSU-A radiances

A. Subramanian

Impact of ocean observation systems on ocean analyses and subseasonal
forecasts in the Indo-Pacific region

N. Raboudi

Ensemble Kalman filtering with colored observation noise

A. Tangborn

Assimilation of AOD retrievals in GEFS-Aerosols using a JEDI-based 3DEnVar Hybrid System

M. Rancic

Preliminary Testing of a Multigrid Beta Filter Scheme for Modeling
Background Error Covariances in NCEP's GSI

J. While

Biases at the base of the mixed layer induced by 3DVar assimilation of sea
surface temperature observations in ocean models.

H. RenEffects of misspecified time-correlated model error in the (ensemble)
Kalman Smoother

K. Sawada

Effects of suppressing supersaturation in a variational data assimilation
system

Y. Shprits

Application of Data Assimilation to Reconstruct the State of the Near-EarthSpace Environment and Issue Space Weather Predictions into the Future.
Development of the tangent linear and adjoint models of the MPASAtmosphere dynamic core and applications in adjoint relative sensitivity
studies

X. Tianall times are in UTC

S. Travova

Soil moisture assimilation system for multilayer soil model

J. WhitakerInitializing high-resolution deterministic forecasts in hybrid-gain and hybridcovariance ensemble DA systems

S.-C. Yang

Including observation error correlation for ensemble radar radial windassimilation and its impact on heavy rainfall prediction

Poster sessions
P4 - Thursday, 16 Sep 2021 (10:00-11:00, 13:00-14:00, 16:00-17:00)
Reanalysis

Observations

A. Andersson

Data rescue of national and international meteorological observations at
Deutscher Wetterdienst

V. Acrc

Accuracy assessment of TRMM precipitation product in different AgroClimatic Zones of Tamil Nadu, India

A. ArshadModeling impact of climate warming on cotton growth and phenology inPakistan from 1961 to 2010 based on provincial data

K. Bathmann

Assessment and Evaluation of Commercial GPS Radio Occultations in the
NCEP Global Forecast System

S. BalAssessment of past and present human biometeorological environment
over WB, India based on observations and Era-Interim

F. Baur

Extending a forward operator for visible satellite channels by near-infrared
and aerosol capabilities

P. Chakraborty

Assessment of temperature extremes based on departures from long-term
reanalysis and high-resolution ensemble forecasts over Indian region

T. ChenSurveying ecology from UAV data using convolutional neural networks inhazard situations

Y. Harada

Early results of the evaluation of the JRA-3Q reanalysis

K. MohanImpact of Satellite Radiance data assimilation on the prediction of extreme
rain events in the haor basin area

J. Herrera

The Panama Bight Index: a new index for the Eastern Tropical Pacific

S. El Mohtar

Bayesian Inference of Oil Spill Source Parameters from Image Contours

B. HooverA kriging method for a gridded quantitative precipitation estimate over
Alaska with uncertainty bounds

F. Fabry

Radar-measured near-surface refractivity: a rare representative constraint
on the lower boundary layer

X. LiangAnalysis of the Wind Fields Based on Radar Network in the East Asia
Reanalysis System

T. Gastaldo

Operational direct assimilation of radar reflectivity volumes with KENDA at
Arpae-SIMC

L. Lima

The 26-Year Black Sea Reanalysis

H. Zhang

Evaluation of multiple GNSS radio occultation observation operators withJEDI

H. Naoe

Evaluation of the latest Japanese Reanalysis for three quarters of acentury (JRA-3Q) during a pre-satellite era

S. Kotsuki

Ensemble-Based Data Assimilation of GPM DPR Reflectivity into the
Nonhydrostatic Icosahedral Atmospheric Model NICAM

A. Nunes

Advances in the Downscaling of Extreme Hydro-Events in South America

V. Lehmann

DWD pilot station - Evaluating ground-based remote sensing systems for
future observing networks

J. Ostermüller

Evaluation of (regional) reanalysis data using the Free Evaluation System
Framework

R. Mangla

Validation of the active microwave sensor module within the RTTOVSCATT radiative transfer model

F. Plöger

The stratospheric Brewer-Dobson circulation in ERA5 and ERA-Interim
reanalyses

M. Mdini

3D Precipitation Nowcasting: RESNet applied to Highly Dense PAWR Data

T. Rösch

Development and Quality Evaluation of an Operational Ensemble-based
Regional Reanalysis System

R. Thundathil

P. Sapiega

J.K. Vishal

Assessment of ERA-5 wave characteristics with in-situ measurements inSouthern Baltic
Ocean Data Impacts on the Reanalysis of Atlantic Meridional overturning
circulation in the Next Generation Global Ocean Data Assimilation System(NG-GODAS)Intercomparison of surface temperature estimates from IMDAA reanalysis
with ERA5 and in-situ observations at selected locations over India

S. Wahl

Evaluation of multi-parameter dependencies in reanalyses

J. Woollen

The NCEP Reanalysis Observation Archive Contents and Formats

H. ZuoThe ORAP6 ocean and sea-ice reanalysis: description and evaluation on
climate and forecasts

Y.-C. Teng

all times are in UTC

E. Villeneuve
X. Wu

Impact of ground-based water vapour and temperature lidar profiles on
short-range forecast skill by means of hybrid 3DVAR-ETKF data
assimilation
A statistical evaluation of Bayesian inversions from infrared and microwave
cloudy observations for future instruments MTG-FCI, MSG-MWI and MSGICIImpact of Atmospheric River Reconnaissance Dropsonde Data on GFS
Precipitation Forecasts: A Case StudyPoster sessions
P5 - Friday, 17 Sep 2021 (10:00-11:00, 13:00-14:00, 16:00-17:00)
General DA

Methodology
T. ChenTimely allocation of resources after natural disasters: Deep learning as atool for damage assessment and saliency mapping

J. Hossen

Using Machine learning techniques to switch background error
distributions to improve data assimilation

T. Deppisch

Exploring the potential of nested EnVAR in the global-to-regional ensemble
system at DWD
Forecast Evaluation of a Deep Convection Case During Relampago
Assimilating Conventional and Satellite Observations with the WRF-GSILETKF System
Assimilation of solar reflectances in a pre-operational online system with alocal ensemble Kalman filter

S. Karozis

A Deep Learning approach for error correction of numerical weather
prediction simulation data

M. Destouches

Hydrometeor control variables in the AROME-France 3DEnVar
assimilation scheme

M. Mdini

Accelerating Climate Model Computation by Neural Networks: A
Comparative Study

L. Duc

1000-member ensemble forecasts for extreme events: the 2019 typhoon
Hagibis and the July 2020 Kyushu heavy rain

J. Purser

Using a Neural Network to choose amplitude and anisotropy parameters ofan adaptive background error covariance

T. Fujita

Enhancement of Variational Assimilation of High-Frequency and HighResolution Radial Winds

Y. Wang

Deep-Learning Augmented Data Assimilation: Reconstructing Missing
Information With Convolutional Autoencoders

N. Gasperoni

Using a cost-effective approach to increase background ensemble size in
EnVar to improve radar analyses and forecasts of convective systems

S. UlbrichSpin-up time from switching the microphysics scheme within theassimilation cycle and impacts on the precipitation forecast quality

P.-Y. Wu

The predictability of the moist convection over different mountain sizes andenvironmental flow conditions

M. Burba
P. Corrales

all times are in UTC

Technical guidelines
GeneralThe WCRP-WWRP Symposium on Data Assimilation and Reanalysis will be held fully virtual due to the ongoing pandemic situation. In orderto let the experience come closer to that of an in-person meeting, we will use the platform Gather.town for the symposium (courtesy of
ECMWF). The platform is browser-based and works with most of the common browsers (e.g., Chrome, Firefox) and operating systems.
In Gather.town, you will create an avatar which you can move around in a virtual conference center. You can visit the posters and access theoral presentations in dedicated rooms. Interactions with other participants will take place when you meet them in the hallways, at the posters
or in other areas. Private spaces allow for smaller groups to retreat and have private discussions. We will enable the access to the platform
before the meeting to allow the participants to get accustomed to it. Guidelines for using Gather.town will follow via email before thesymposium takes place.
Oral presentations•

During the sessions, presenters will share their screen to show their slides. In case of technical issues, the session chairs can show theslides on their screen as a backup. Therefore, we would like to ask presenters to also upload their presentation in PDF format at leaston the day prior to the talk. Details on how to upload the presentations will follow in the week prior to the symposium.

•

The oral slots will be 15 minutes consisting of 12 minutes for the presentation and 3 minutes for discussion. If you use all 15 minutes foryour presentation, the discussion will be skipped.

•

We suggest to use a 16:9 or 16:10 ratio for the presentation as this better fits the majority of screens.

Poster presentations•

Posters must be provided before September 6. Information on the upload process has been sent via email.

•

Each poster session comprises 3 hours distributed over one day.

•All posters will be accessible during the whole symposium. Each poster has an assigned session (day) where the presenter is encouraged
to be present.

•

Posters have to be provided in PDF format.

•

We suggest to use landscape format and similar settings as for printed posters (e.g., A0 format, high quality) for a better experience ingathertown.