Assessment of Sea Ice Extent in CMIP6 With Comparison to Observations and CMIP5

Shu, Qi; Wang, Qiang; Song, Zhenya; Qiao, Fangli; Zhao, Jiechen; Chu, Min; Li, Xinfang

doi:10.1029/2020gl087965

Cited by 128 publications

(126 citation statements)

References 23 publications

Supporting

Mentioning

105

Contrasting

Unclassified

Order By: Relevance

“…A higher horizontal resolution may not be the answer as, depending on the model, it either reduces (Danek et al, 2019) or increases deep convection even further (Koenigk et al, 2020). In the ocean component, one solution could be a more systematic inclusion of overflow parameterisation (Snow et al, 2015); in this study, it seems very effective for CESM2. The one data-assimilating model, NorCPM (Counillon et al, 2016), also proposes an interesting option.…”

Section: Discussionmentioning

confidence: 87%

“…The models that convect the least or not at all tend to be the most accurate. For the CESM2 family, accurate bottom properties and lack of deep convection may both be the result of their overflow parameterisation (Briegleb et al, 2010;Snow et al, 2015). For another model, NorCPM1, the accuracy in all properties may come from its observation assimilation rather than accurate model physics (Counillon et al, 2016).…”

Section: Aabw Propertiesmentioning

confidence: 99%

“…Higher-resolution output will be impossible to manage, unless cloud-computing solutions such as PANGEO become the norm (Odaka et al, 2020). Instead of increasing the resolution, a seemingly easier solution would be to improve parameterisations (Holt et al, 2017), especially overflow parameterisations (Snow et al, 2015). Briegleb et al (2010) first showed that an overflow parameterisation to transport water from the Nordic seas to the rest of the North Atlantic resulted in an improved representation of the ocean there.…”

Section: Global Transport Of Nadw and Aabw In Cmip6 Modelsmentioning

confidence: 99%

See 2 more Smart Citations

Antarctic Bottom Water and North Atlantic Deep Water in CMIP6 models

Heuzé¹

2021

Ocean Sci.

118

106

View full text Add to dashboard Cite

Abstract. Deep and bottom water formation are crucial components of the global ocean circulation, yet they were poorly represented in the previous generation of climate models. We here quantify biases in Antarctic Bottom Water (AABW) and North Atlantic Deep Water (NADW) formation, properties, transport, and global extent in 35 climate models that participated in the latest Climate Model Intercomparison Project (CMIP6). Several CMIP6 models are correctly forming AABW via shelf processes, but 28 models in the Southern Ocean and all 35 models in the North Atlantic form deep and bottom water via open-ocean deep convection too deeply, too often, and/or over too large an area. Models that convect the least form the most accurate AABW but the least accurate NADW. The four CESM2 models with their overflow parameterisation are among the most accurate models. In the Atlantic, the colder the AABW, the stronger the abyssal overturning at 30∘ S, and the further north the AABW layer extends. The saltier the NADW, the stronger the Atlantic Meridional Overturning Circulation (AMOC), and the further south the NADW layer extends. In the Indian and Pacific oceans in contrast, the fresher models are the ones which extend the furthest regardless of the strength of their abyssal overturning, most likely because they are also the models with the weakest fronts in the Antarctic Circumpolar Current. There are clear improvements since CMIP5: several CMIP6 models correctly represent or parameterise Antarctic shelf processes, fewer models exhibit Southern Ocean deep convection, more models convect at the right location in the Labrador Sea, bottom density biases are reduced, and abyssal overturning is more realistic. However, more improvements are required, e.g. by generalising the use of overflow parameterisations or by coupling to interactive ice sheet models, before deep and bottom water formation, and hence heat and carbon storage, are represented accurately.

show abstract

Section: Discussionmentioning

confidence: 87%

Section: Aabw Propertiesmentioning

confidence: 99%

Section: Global Transport Of Nadw and Aabw In Cmip6 Modelsmentioning

confidence: 99%

See 1 more Smart Citation

Antarctic Bottom Water and North Atlantic Deep Water in CMIP6 models

Heuzé¹

2021

Ocean Sci.

118

106

View full text Add to dashboard Cite

show abstract

“…The observations are available on a 0.25° latitude by 0.25° longitude grid. A comparison of regional sea ice trends in CMIP6 models with that in previous generation of climate models (CMIP5) is not performed here (see Davy and Outten [2020], Notz et al [2020], and Shu et al [2020] for a comparison of pan-Arctic sea ice extent/area).…”

Section: Methodsmentioning

confidence: 99%

The Seasonal and Regional Transition to an Ice‐Free Arctic

Årthun

Onarheim

Dörr

et al. 2021

Geophysical Research Letters

View full text Add to dashboard Cite

The Arctic sea ice cover has decreased in all seasons and all regions since satellite observations started in 1979 (Comiso et al., 2017; Onarheim et al., 2018), serving as a visible manifestation of ongoing climate change (Serreze et al., 2007). These changes in sea ice cover potentially impact several aspects of climate in the Arctic and lower latitudes, including ocean circulation and hydrography (

show abstract

“…AWI-FESOM is a global configuration of the Finite Element/volumE Sea ice-Ocean Model (FESOM) version 1.4 (Wang et al, 2014;Danilov et al, 2015) of the Alfred Wegener Institute Climate Model (AWI-CM; Sidorenko et al, 2015Sidorenko et al, , 2018Rackow et al, 2018Rackow et al, , 2019Sein et al, 2018). Both the ocean and sea ice modules work on unstructured triangular meshes (Danilov et al, 2004;Wang et al, 2008), thus allowing for multi-resolution simulations.…”

Section: Awi-fesommentioning

confidence: 99%

Impact of horizontal resolution on global ocean–sea ice model simulations based on the experimental protocols of the Ocean Model Intercomparison Project phase 2 (OMIP-2)

et al. 2020

Self Cite

View full text Add to dashboard Cite

Abstract. This paper presents global comparisons of fundamental global climate variables from a suite of four pairs of matched low- and high-resolution ocean and sea ice simulations that are obtained following the OMIP-2 protocol (Griffies et al., 2016) and integrated for one cycle (1958–2018) of the JRA55-do atmospheric state and runoff dataset (Tsujino et al., 2018). Our goal is to assess the robustness of climate-relevant improvements in ocean simulations (mean and variability) associated with moving from coarse (∼ 1∘) to eddy-resolving (∼ 0.1∘) horizontal resolutions. The models are diverse in their numerics and parameterizations, but each low-resolution and high-resolution pair of models is matched so as to isolate, to the extent possible, the effects of horizontal resolution. A variety of observational datasets are used to assess the fidelity of simulated temperature and salinity, sea surface height, kinetic energy, heat and volume transports, and sea ice distribution. This paper provides a crucial benchmark for future studies comparing and improving different schemes in any of the models used in this study or similar ones. The biases in the low-resolution simulations are familiar, and their gross features – position, strength, and variability of western boundary currents, equatorial currents, and the Antarctic Circumpolar Current – are significantly improved in the high-resolution models. However, despite the fact that the high-resolution models “resolve” most of these features, the improvements in temperature and salinity are inconsistent among the different model families, and some regions show increased bias over their low-resolution counterparts. Greatly enhanced horizontal resolution does not deliver unambiguous bias improvement in all regions for all models.

show abstract

Assessment of Sea Ice Extent in CMIP6 With Comparison to Observations and CMIP5

Cited by 128 publications

References 23 publications

Antarctic Bottom Water and North Atlantic Deep Water in CMIP6 models

Antarctic Bottom Water and North Atlantic Deep Water in CMIP6 models

The Seasonal and Regional Transition to an Ice‐Free Arctic

Impact of horizontal resolution on global ocean–sea ice model simulations based on the experimental protocols of the Ocean Model Intercomparison Project phase 2 (OMIP-2)

Contact Info

Product

Resources

About