de Souza, Mihael Machado; Mathis, Moritz; Pohlmann, Thomas
ExperimentDOI
Summary
This experiment aims to investigate the impact of anthropogenic climate change to the stratification of the Brazilian shelf waters under a strong warming scenario (RCP8.5).
Earth System Models (ESMs) predict a stronger increase in stratification over the equatorial regions, due to the increased surface warming. However, they cannot account for all relevant regional processes due to their coarse horizontal resolution.
One of the more relevant local processes unresolved by ESMs is the upwelling of South Atlantic Central Water along subtropical Brazil. It brings cold and nutrient-rich waters towards the coast to the most productive shelf regions along the Brazilian coastal waters and is known to play an important role in the stratification of the South Brazil Bight.
By including this process in our analysis through our downscaling experiment, we can provide a more complete assessment of the effects of increased greenhouse gas emissions in the stratification of the Brazilian continental shelf.
de Souza, Mihael Machado; Mathis, Moritz; Pohlmann, Thomas (2020). Model output prepared in support of the analysis of impacts to the stratification along the Brazilian shelf under a strong warming scenario (RCP8.5). World Data Center for Climate (WDCC) at DKRZ. https://doi.org/10.26050/WDCC/ECC-BRS_HAMSOM
Approved by Mihael Machado de Souza on 4th of August, 2020.
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Description
Approved by Mihael Machado de Souza on 4th of August, 2020.
The general model description and the model validation can be found in https://doi.org/10.1007/s00382-019-04942-7.
Model: HAMSOM
HAMburg Shelf Ocean Model
HAMSOM is a three-dimensional, baroclinic, free surface, shallow-water equations model. It relies on the hydrostatic and Boussinesq approximations and is defined based on Z-coordinates on the staggered Arakawa C-grid.
The advection of temperature and salinity is formulated with a second order Lax-Wendroff scheme, while the advection of momentum is formulated using the component upstream method. The semi-implicit formulation leads to an elliptical partial differential equation that is solved using the SOR “red-black” method. The vertical eddy viscosity is parametrized using the Kochergin method and is dependent on the vertical velocity gradient and the water column stability. The Smagorinsky scheme is employed for the horizontal viscosity and is based on the horizontal velocity shear.
Closed boundaries are defined under a semi-slip and zero flux condition. At open boundaries a zero gradient is enforced and a Sommerfeld radiation scheme is applied for outflowing temperature and salinity. River inflow is treated as a temperature, salinity and volume change at the respective model cell. Surface exchange flows are calculated through bulk-formulas and a
quadratic stress law is applied at the bottom boundary.
Model references:
Backhaus, J.O. 1985 ( doi:10.1007/BF02328975 )
Pohlmann, T. 1996 ( doi:10.1016/0278-4343(95)90885-s )
Pohlmann, T. 2006 ( doi:10.1016/j.csr.2006.06.011 )
Completeness report
All parameters cover the region from below the Amazon Plume to the south of Brazil, capturing the full shelf waters.
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Description
All parameters cover the region from below the Amazon Plume to the south of Brazil, capturing the full shelf waters.
Data is provided as monthly means from 1970 to 2100.
Surface data refers to the first model cell, equivalent to a water column of 5 meters. Potential energy anomaly and pycnocline characteristics are calculated based on the full vertical density profile.
FAIR
F-UJI result: total 66 %
Description
Summary: Findable: 6 of 7 level; Accessible: 2 of 3 level; Interoperable: 3 of 4 level; Reusable: 5 of 10 level
SQA - Scientific Quality Assurance 'approved by author'
Result Date
2020-08-15
Technical Quality Assurance (TQA)
TQA - Technical Quality Assurance 'approved by WDCC'
Description
1. Number of data sets is correct and > 0: passed; 2. Size of every data set is > 0: passed; 3. The data sets and corresponding metadata are accessible: passed; 4. The data sizes are controlled and correct: passed; 5. The temporal coverage description (metadata) is consistent to the data, time steps are correct: passed; 6. The format is correct: passed
Method
WDCC-TQA checklist
Method Description
Checks performed by WDCC. The list of TQA metrics are documented in the 'WDCC User Guide for Data Publication' Chapter 8.1.1
[1] DOIde Souza, Mihael M.; Mathis, Moritz; Pohlmann, Thomas. (2019). Driving mechanisms of the variability and long-term trend of the Brazil–Malvinas confluence during the 21st century. doi:10.1007/s00382-019-04942-7
[2] DOIBackhaus, Jan O. (1985). A three-dimensional model for the simulation of shelf sea dynamics. doi:10.1007/bf02328975
[3] DOIPohlmann, Thomas. (2007). A meso-scale model of the central and southern North Sea: Consequences of an improved resolution. doi:10.1016/j.csr.2006.06.011
[4] DOIPohlmann, Thomas. (1996). Predicting the thermocline in a circulation model of the North sea — part I: model description, calibration and verification. doi:10.1016/0278-4343(95)90885-s