elib
DLR-Header
DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Privacy Policy | Contact | Deutsch
Fontsize: [-] Text [+]

Observation of jet stream winds during NAWDEX and characterization of systematic meteorological analysis errors

Schäfler, Andreas and Harvey, Ben and Methven, John and Doyle, James D. and Rahm, Stephan and Reitebuch, Oliver and Weiler, Fabian and Witschas, Benjamin (2020) Observation of jet stream winds during NAWDEX and characterization of systematic meteorological analysis errors. Monthly Weather Review, 148 (7), pp. 2889-2907. American Meteorological Society. DOI: 10.1175/MWR-D-19-0229.1 ISSN 0027-0644

[img] PDF - Registered users only - Published version
3MB

Official URL: https://journals.ametsoc.org/doi/abs/10.1175/MWR-D-19-0229.1

Abstract

Observations across the North Atlantic jet stream with high vertical resolution are used to explore the structure of the jet stream, including the sharpness of vertical wind shear changes across the tropopause and the wind speed. Data was obtained during the North Atlantic Waveguide and Downstream impact EXperiment (NAWDEX) by an airborne Doppler wind lidar, dropsondes and a ground-based Stratosphere-Troposphere radar. During the campaign small wind speed biases throughout the troposphere and lower stratosphere of only -0.41 m s-1 and -0.15 m s-1 are found respectively in the ECMWF and UK Met Office analyses and short-term forecasts. However, this study finds large and spatially coherent wind errors up to ±10 m s-1 for individual cases, with the strongest errors occurring above the tropopause in upper-level ridges. ECMWF and Met Office analyses indicate similar spatial structures in wind errors, even though their forecast models and data assimilation schemes differ greatly. The assimilation of operational observational data brings the analyses closer to the independent verifying observations but it cannot fully compensate the forecast error. Models tend to underestimate the peak jet stream wind, the vertical wind shear (by a factor of 2-5) and the abruptness of the change in wind shear across the tropopause, which is a major contribution to the meridional potential vorticity gradient. The differences are large enough to influence forecasts of Rossby wave disturbances to the jet stream with an anticipated effect on weather forecast skill even on large scales.

Item URL in elib:https://elib.dlr.de/135417/
Document Type:Article
Title:Observation of jet stream winds during NAWDEX and characterization of systematic meteorological analysis errors
Authors:
AuthorsInstitution or Email of AuthorsAuthor's ORCID iD
Schäfler, AndreasDLR, IPAhttps://orcid.org/0000-0002-6165-6623
Harvey, BenUniv. of Reading, UKUNSPECIFIED
Methven, JohnUniv. of Reading, UKUNSPECIFIED
Doyle, James D.NRL, Monterey, CA, USAUNSPECIFIED
Rahm, StephanDLR, IPAUNSPECIFIED
Reitebuch, OliverDLR, IPAhttps://orcid.org/0000-0002-8503-0094
Weiler, FabianDLR, IPAUNSPECIFIED
Witschas, BenjaminDLR, IPAhttps://orcid.org/0000-0001-7993-1470
Date:July 2020
Journal or Publication Title:Monthly Weather Review
Refereed publication:Yes
Open Access:No
Gold Open Access:No
In SCOPUS:Yes
In ISI Web of Science:Yes
Volume:148
DOI :10.1175/MWR-D-19-0229.1
Page Range:pp. 2889-2907
Publisher:American Meteorological Society
ISSN:0027-0644
Status:Published
Keywords:Doppler wind lidar, field campaign, model analyses
HGF - Research field:Aeronautics, Space and Transport
HGF - Program:Space
HGF - Program Themes:Earth Observation
DLR - Research area:Raumfahrt
DLR - Program:R EO - Erdbeobachtung
DLR - Research theme (Project):R - Vorhaben LIDAR-Forschung und -Entwicklung
Location: Oberpfaffenhofen
Institutes and Institutions:Institute of Atmospheric Physics
Institute of Atmospheric Physics > Lidar
Deposited By: Schäfler, Andreas
Deposited On:29 Jun 2020 10:39
Last Modified:29 Jun 2020 10:39

Repository Staff Only: item control page

Browse
Search
Help & Contact
Information
electronic library is running on EPrints 3.3.12
Copyright © 2008-2017 German Aerospace Center (DLR). All rights reserved.