Representation of precipitation and top-of-atmosphere radiation in a multi-model convection-permitting ensemble for the Lake Victoria Basin (East-Africa)
(2023) In Climate Dynamics 60(11-12). p.4033-4054- Abstract
The CORDEX Flagship Pilot Study ELVIC (climate Extremes in the Lake VICtoria basin) was recently established to investigate how extreme weather events will evolve in this region of the world and to provide improved information for the climate impact community. Here we assess the added value of the convection-permitting scale simulations on the representation of moist convective systems over and around Lake Victoria. With this aim, 10 year present-day model simulations were carried out with five regional climate models at both PARameterized (PAR) scales (12–25 km) and Convection-Permitting (CP) scales (2.5–4.5 km), with COSMO-CLM, RegCM, AROME, WRF and UKMO. Most substantial systematic improvements were found in metrics related to deep... (More)
The CORDEX Flagship Pilot Study ELVIC (climate Extremes in the Lake VICtoria basin) was recently established to investigate how extreme weather events will evolve in this region of the world and to provide improved information for the climate impact community. Here we assess the added value of the convection-permitting scale simulations on the representation of moist convective systems over and around Lake Victoria. With this aim, 10 year present-day model simulations were carried out with five regional climate models at both PARameterized (PAR) scales (12–25 km) and Convection-Permitting (CP) scales (2.5–4.5 km), with COSMO-CLM, RegCM, AROME, WRF and UKMO. Most substantial systematic improvements were found in metrics related to deep convection. For example, the timing of the daily maximum in precipitation is systematically delayed in CP compared to PAR models, thereby improving the agreement with observations. The large overestimation in the total number of rainy events is alleviated in the CP models. Systematic improvements were found in the diurnal cycle in Top-Of-Atmosphere (TOA) radiation and in some metrics for precipitation intensity. No unanimous improvement nor deterioration was found in the representation of the spatial distribution of total rainfall and the seasonal cycle when going to the CP scale. Furthermore, some substantial biases in TOA upward radiative fluxes remain. Generally our analysis indicates that the representation of the convective systems is strongly improved in CP compared to PAR models, giving confidence that the models are valuable tools for studying how extreme precipitation events may evolve in the future in the Lake Victoria basin and its surroundings.
(Less)
- author
- Lipzig, Nicole P.M.van
; Walle, Jonas Van de
; Belušić, Danijel
; Berthou, Ségolène
; Coppola, Erika
; Demuzere, Matthias
; Fink, Andreas H.
; Finney, Declan L.
; Glazer, Russell
; Ludwig, Patrick
; Marsham, John H.
; Nikulin, Grigory
; Pinto, Joaquim G.
; Rowell, David P.
; Wu, Minchao
LU
and Thiery, Wim
(Less) - organization
- publishing date
- 2023
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Convection permitting simulations, CORDEX Flagship Pilot Study, Equatorial Africa, Extreme weather events, Kilometer-scale resolution, Lake Victoria basin, Regional climate models, Tropical deep convection
- in
- Climate Dynamics
- volume
- 60
- issue
- 11-12
- pages
- 4033 - 4054
- publisher
- Springer
- external identifiers
-
- scopus:85141352536
- ISSN
- 0930-7575
- DOI
- 10.1007/s00382-022-06541-5
- language
- English
- LU publication?
- yes
- id
- 8196602c-4d84-4e09-97ae-31aabb51d2cd
- date added to LUP
- 2022-12-21 11:44:09
- date last changed
- 2024-05-30 13:33:24
@article{8196602c-4d84-4e09-97ae-31aabb51d2cd,
abstract = {{<p>The CORDEX Flagship Pilot Study ELVIC (climate Extremes in the Lake VICtoria basin) was recently established to investigate how extreme weather events will evolve in this region of the world and to provide improved information for the climate impact community. Here we assess the added value of the convection-permitting scale simulations on the representation of moist convective systems over and around Lake Victoria. With this aim, 10 year present-day model simulations were carried out with five regional climate models at both PARameterized (PAR) scales (12–25 km) and Convection-Permitting (CP) scales (2.5–4.5 km), with COSMO-CLM, RegCM, AROME, WRF and UKMO. Most substantial systematic improvements were found in metrics related to deep convection. For example, the timing of the daily maximum in precipitation is systematically delayed in CP compared to PAR models, thereby improving the agreement with observations. The large overestimation in the total number of rainy events is alleviated in the CP models. Systematic improvements were found in the diurnal cycle in Top-Of-Atmosphere (TOA) radiation and in some metrics for precipitation intensity. No unanimous improvement nor deterioration was found in the representation of the spatial distribution of total rainfall and the seasonal cycle when going to the CP scale. Furthermore, some substantial biases in TOA upward radiative fluxes remain. Generally our analysis indicates that the representation of the convective systems is strongly improved in CP compared to PAR models, giving confidence that the models are valuable tools for studying how extreme precipitation events may evolve in the future in the Lake Victoria basin and its surroundings.</p>}},
author = {{Lipzig, Nicole P.M.van and Walle, Jonas Van de and Belušić, Danijel and Berthou, Ségolène and Coppola, Erika and Demuzere, Matthias and Fink, Andreas H. and Finney, Declan L. and Glazer, Russell and Ludwig, Patrick and Marsham, John H. and Nikulin, Grigory and Pinto, Joaquim G. and Rowell, David P. and Wu, Minchao and Thiery, Wim}},
issn = {{0930-7575}},
keywords = {{Convection permitting simulations; CORDEX Flagship Pilot Study; Equatorial Africa; Extreme weather events; Kilometer-scale resolution; Lake Victoria basin; Regional climate models; Tropical deep convection}},
language = {{eng}},
number = {{11-12}},
pages = {{4033--4054}},
publisher = {{Springer}},
series = {{Climate Dynamics}},
title = {{Representation of precipitation and top-of-atmosphere radiation in a multi-model convection-permitting ensemble for the Lake Victoria Basin (East-Africa)}},
url = {{http://dx.doi.org/10.1007/s00382-022-06541-5}},
doi = {{10.1007/s00382-022-06541-5}},
volume = {{60}},
year = {{2023}},
}