[ecco-support] [EXTERNAL] ECCO2 seafloor pressure simulations

[Zhang, Hong (US 398K)]

> On Jun 16, 2021, at 6:23 PM, Katie Woods <katherine14.woods at gmail.com> wrote:
> 
> Hi there,
> 
> I'm researching how well global ocean models simulate seafloor pressure (compared to recorded seafloor pressure at points from 800 m - 3400 m depth) off the east coast of New Zealand, and have noted that ECCO2 does a surprisingly good job in relation to GLORYS and HYCOM, considering it has much poorer spatial resolution that those two models. I was wondering if someone at ECCO might be able to help me understand why this is the case?
> 
> I am using the output PHIBOT parameter from ECCO2, and for the other two models I'm converting the salinity-temperature profiles and sea-surface height anomalies to seafloor pressure.
Hi Katie,
thanks for your interest in ECCO2 product.
Great that you find the good agreement.
Actually there are many studies using ECCO2 bottom pressure output,
just name a few here:

Nonseasonal fluctuations of the Arctic Ocean mass observed by the GRACE satellites
https://doi.org/10.1002/2013JC009341

Arctic Ocean Circulation Patterns Revealed by GRACE
https://doi.org/10.1175/JCLI-D-13-00013.1                         

Tide gauge records reveal improved processing of gravity recovery and climate experiment time-variable mass solutions over the coastal ocean
https://doi.org/10.1093/gji/ggy207

Ocean Bottom Pressure Variability: Can It Be Reliably Modeled?
https://doi.org/10.1029/2019JC015469

Interestingly, this paper
Improving Detectability of Seafloor Deformation From Bottom Pressure Observations Using Numerical Ocean Models
https://doi.org/10.3389/feart.2020.598270
also looks at GLORYS and HYCOM, similar to your method.

One possible reason for the fidelity is that it’s data-assimilated? 
not sure how GLORYS and HYCOM work.
best,
Hong