Changeset 14303


Ignore:
Timestamp:
2021-01-14T18:26:35+01:00 (5 months ago)
Author:
mathiot
Message:

ticket #2444: update doc (isf, clo, icb)

Location:
NEMO/trunk/doc
Files:
6 edited

Legend:

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  • NEMO/trunk/doc/latex/NEMO/main/bibliography.bib

    r14116 r14303  
    119119  issn          = "0148-0227", 
    120120  doi           = "10.1029/2001jc000922" 
     121} 
     122 
     123@Article{         Asaydavis2016, 
     124  author        = {Asay-Davis, X. S. and Cornford, S. L. and Durand, G. and Galton-Fenzi, B. K. and Gladstone, R. M. and Gudmundsson, G. H. and Hattermann, T. and Holland, D. M. and Holland, D. and Holland, P. R. and Martin, D. F. and Mathiot, P. and Pattyn, F. and Seroussi, H.}, 
     125  title         = {Experimental design for three interrelated marine ice sheet and ocean model intercomparison projects: MISMIP v. 3 (MISMIP$+$), ISOMIP v. 2 (ISOMIP$+$) and MISOMIP v. 1 (MISOMIP1)}, 
     126  journal       = {Geoscientific Model Development}, 
     127  volume        = {9}, 
     128  year          = {2016}, 
     129  number        = {7}, 
     130  pages         = {2471--2497}, 
     131  url           = {https://www.geosci-model-dev.net/9/2471/2016/}, 
     132  doi           = {10.5194/gmd-9-2471-2016} 
    121133} 
    122134 
     
    878890} 
    879891 
     892@Article{         favier2019, 
     893  author        = {Favier, L. and Jourdain, N. C. and Jenkins, A. and Merino, N. and Durand, G. and Gagliardini, O. and Gillet-Chaulet, F. and Mathiot, P.}, 
     894  title         = {Assessment of sub-shelf melting parameterisations using the ocean--ice-sheet coupled model NEMO(v3.6)--Elmer/Ice(v8.3)}, 
     895  journal       = {Geoscientific Model Development}, 
     896  volume        = {12}, 
     897  year          = {2019}, 
     898  number        = {6}, 
     899  pages         = {2255--2283}, 
     900  url           = {https://www.geosci-model-dev.net/12/2255/2019/}, 
     901  doi           = {10.5194/gmd-12-2255-2019} 
     902} 
     903 
    880904@article{         flather_JPO94, 
    881905  title         = "A storm surge prediction model for the northern Bay of 
     
    11861210} 
    11871211 
     1212@article{         grosfeld1997, 
     1213author          = {Grosfeld, K. and Gerdes, R. and Determann, J.}, 
     1214title           = {Thermohaline circulation and interaction between ice shelf cavities and the adjacent open ocean}, 
     1215journal         = {Journal of Geophysical Research: Oceans}, 
     1216 
     1217volume          = {102}, 
     1218number          = {C7}, 
     1219pages           = {15595-15610}, 
     1220doi             = {10.1029/97JC00891}, 
     1221url             = {https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/97JC00891}, 
     1222year            = {1997} 
     1223} 
     1224 
    11881225@article{         guilyardi.madec.ea_CD01, 
    11891226  title         = "The role of lateral ocean physics in the upper ocean 
     
    14141451  issn          = "0148-0227", 
    14151452  doi           = "10.1029/91jc01842" 
     1453} 
     1454 
     1455@article{         jenkins2001, 
     1456  author        = {Jenkins, Adrian and Hellmer, Hartmut H. and Holland, David M.}, 
     1457  title         = {The Role of Meltwater Advection in the Formulation of Conservative Boundary Conditions at an Ice–Ocean Interface}, 
     1458  journal       = {Journal of Physical Oceanography}, 
     1459  volume        = {31}, 
     1460  number        = {1}, 
     1461  pages         = {285-296}, 
     1462  year          = {2001}, 
     1463  doi           = {10.1175/1520-0485(2001)031<0285:TROMAI>2.0.CO;2}, 
     1464  url           = {https://doi.org/10.1175/1520-0485(2001)031<0285:TROMAI>2.0.CO;2} 
     1465} 
     1466 
     1467@article{         jourdain2017, 
     1468  author        = {Jourdain, Nicolas C. and Mathiot, Pierre and Merino, Nacho and Durand, Gaël and Le Sommer, Julien and Spence, Paul and Dutrieux, Pierre and Madec, Gurvan}, 
     1469  title         = {Ocean circulation and sea-ice thinning induced by melting ice shelves in the Amundsen Sea}, 
     1470  journal       = {Journal of Geophysical Research: Oceans}, 
     1471  volume        = {122}, 
     1472  number        = {3}, 
     1473  pages         = {2550-2573}, 
     1474  keywords      = {Amundsen Sea, ice shelf, efficiency, circumpolar deep water, ocean circulation, sea ice}, 
     1475  doi           = {10.1002/2016JC012509}, 
     1476  url           = {https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1002/2016JC012509}, 
     1477  year          = {2017} 
    14161478} 
    14171479 
     
    22262288} 
    22272289 
     2290@article{Merino_OM2016, 
     2291title = "Antarctic icebergs melt over the Southern Ocean: Climatology and impact on sea ice", 
     2292journal = "Ocean Modelling", 
     2293volume = "104", 
     2294pages = "99 - 110", 
     2295year = "2016", 
     2296issn = "1463-5003", 
     2297doi = "https://doi.org/10.1016/j.ocemod.2016.05.001", 
     2298url = "http://www.sciencedirect.com/science/article/pii/S1463500316300300", 
     2299author = "Nacho Merino and Julien {Le Sommer} and Gael Durand and Nicolas C. Jourdain and Gurvan Madec and Pierre Mathiot and Jean Tournadre", 
     2300keywords = "Icebergs, Southern Ocean, Sea ice, Freshwater fluxes", 
     2301abstract = "Recent increase in Antarctic freshwater release to the Southern Ocean is suggested to contribute to change in water masses and sea ice. However, climate models differ in their representation of the freshwater sources. Recent improvements in altimetry-based detection of small icebergs and in estimates of the mass loss of Antarctica may help better constrain the values of Antarctic freshwater releases. We propose a model-based seasonal climatology of iceberg melt over the Southern Ocean using state-of-the-art observed glaciological estimates of the Antarctic mass loss. An improved version of a Lagrangian iceberg model is coupled with a global, eddy-permitting ocean/sea ice model and compared to small icebergs observations. Iceberg melt increases sea ice cover, about 10% in annual mean sea ice volume, and decreases sea surface temperature over most of the Southern Ocean, but with distinctive regional patterns. Our results underline the importance of improving the representation of Antarctic freshwater sources. This can be achieved by forcing ocean/sea ice models with a climatological iceberg fresh-water flux." 
     2302} 
     2303 
    22282304@article{         merryfield.holloway.ea_JPO99, 
    22292305  title         = "A Global Ocean Model with Double-Diffusive Mixing", 
  • NEMO/trunk/doc/latex/NEMO/subfiles/apdx_DOMAINcfg.tex

    r14257 r14303  
    1616    Release & Author(s) & Modifications \\ 
    1717    \hline 
    18     {\em   4.0} & {\em ...} & {\em ...} \\ 
     18    {\em   next}& {\em Pierre Mathiot} & {\em add ice shelf and closed sea option description } \\ 
     19    {\em   4.0} & {\em Andrew Coward}  & {\em Created at v4.0 from materials removed from chap\_DOM that are still relevant to the \forcode{DOMAINcfg} tool and which illustrate and explain the choices to be made by the user when setting up new domains }  \\ 
    1920    {\em   3.6} & {\em ...} & {\em ...} \\ 
    2021    {\em   3.4} & {\em ...} & {\em ...} \\ 
     
    350351  Defining the bathymetry also defines the coastline: where the bathymetry is zero, 
    351352  no wet levels are defined (all levels are masked). 
    352  
    353   The \textit{isfdraft\_meter.nc} file (Netcdf format) provides the ice shelf draft (positive, in meters) at 
    354   each grid point of the model grid. 
    355   This file is only needed if \np[=.true.]{ln_isfcav}{ln\_isfcav}. 
    356   Defining the ice shelf draft will also define the ice shelf edge and the grounding line position. 
    357353\end{description} 
    358354 
     
    590586This option is described in the Report by Levier \textit{et al.} (2007), available on the \NEMO\ web site. 
    591587 
     588\section{Ice shelf cavity definition} 
     589\label{subsec:zgrisf} 
     590 
     591  If the under ice shelf seas are opened (\np{ln_isfcav}{ln\_isfcav}), the depth of the ice shelf/ocean interface has to be include in  
     592  the \textit{isfdraft\_meter} file (Netcdf format). This file need to include the \textit{isf\_draft} variable.  
     593  A positive value will mean ice shelf/ocean or ice shelf bedrock interface below the reference 0m ssh.  
     594  The exact shape of the ice shelf cavity (grounding line position and minimum thickness of the water column under an ice shelf, ...) can be specify in \nam{zgr_isf}{zgr_isf}. 
     595 
     596\begin{listing} 
     597  \caption{\forcode{&namzgr_isf}} 
     598  \label{lst:namzgr_isf} 
     599  \begin{forlines} 
     600!----------------------------------------------------------------------- 
     601&namzgr_isf    !   isf cavity geometry definition                       (default: OFF) 
     602!----------------------------------------------------------------------- 
     603   rn_isfdep_min    = 10.         ! minimum isf draft tickness (if lower, isf draft set to this value) 
     604   rn_glhw_min      = 1.e-3       ! minimum water column thickness to define the grounding line 
     605   rn_isfhw_min     = 10          ! minimum water column thickness in the cavity once the grounding line defined. 
     606   ln_isfchannel    = .false.     ! remove channel (based on 2d mask build from isfdraft-bathy) 
     607   ln_isfconnect    = .false.     ! force connection under the ice shelf (based on 2d mask build from isfdraft-bathy) 
     608      nn_kisfmax       = 999         ! limiter in level on the previous condition. (if change larger than this number, get back to value before we enforce the connection) 
     609      rn_zisfmax       = 7000.       ! limiter in m     on the previous condition. (if change larger than this number, get back to value before we enforce the connection) 
     610   ln_isfcheminey   = .false.     ! close cheminey 
     611   ln_isfsubgl      = .false.     ! remove subglacial lake created by the remapping process 
     612      rn_isfsubgllon   =    0.0      !  longitude of the seed to determine the open ocean 
     613      rn_isfsubgllat   =    0.0      !  latitude  of the seed to determine the open ocean 
     614/ 
     615  \end{forlines} 
     616\end{listing} 
     617 
     618   The options available to define the shape of the under ice shelf cavities are listed in \nam{zgr_isf}{zgr_isf} (\texttt{DOMAINcfg} only, \autoref{lst:namzgr_isf}). 
     619 
     620   \subsection{Model ice shelf draft definition} 
     621   \label{subsec:zgrisf_isfd} 
     622 
     623   First of all, the tool make sure, the ice shelf draft ($h_{isf}$) is sensible and compatible with the bathymetry. 
     624   There are 3 compulsory steps to achieve this: 
     625 
     626   \begin{description} 
     627   \item{\np{rn_isfdep_min}{rn\_isfdep\_min}:} this is the minimum ice shelf draft. This is to make sure there is no ridiculous thin ice shelf. If \np{rn_isfdep_min}{rn\_isfdep\_min} is smaller than the surface level, \np{rn_isfdep_min}{rn\_isfdep\_min} is set to $e3t\_1d(1)$.  
     628   Where $h_{isf} < MAX(e3t\_1d(1),\np{rn_isfdep_min}{rn\_isfdep\_min}$), $h_{isf}$ is set to \np{rn_isfdep_min}{rn\_isfdep\_min}. 
     629 
     630   \item{\np{rn_glhw_min}{rn\_glhw\_min}:} This parameter is used to define the grounding line position. 
     631   Where the difference between the bathymetry and the ice shelf draft is smaller than \np{rn_glhw_min}{rn\_glhw\_min}, the cell are grounded (ie masked).  
     632   This step is needed to take into account possible small mismatch between ice shelf draft value and bathymetry value (sources are coming from different grid, different data processes, rounding error, ...). 
     633 
     634   \item{\np{rn_isfhw_min}{rn\_isfhw\_min}:} This parameter is the minimum water column thickness in the cavity.  
     635   Where the water column thickness is lower than \np{rn_isfhw_min}{rn\_isfhw\_min}, the ice shelf draft is adjusted to match this criterion.  
     636   If for any reason, this adjustement break the minimum ice shelf draft allowed (\np{rn_isfdep_min}{rn\_isfdep\_min}), the cell is masked. 
     637   \end{description} 
     638 
     639   Once all these adjustements are made, if the water column thickness contains one cell wide channels, these channels can be closed using \np{ln_isfchannel}{ln\_isfchannel}.   
     640  
     641   \subsection{Model top level definition} 
     642   After the definition of the ice shelf draft, the tool defines the top level.  
     643   The compulsory criterion is that the water column needs at least 2 wet cells in the water column at U- and V-points. 
     644   To do so, if there one cell wide water column, the tools adjust the ice shelf draft to fillful the requierement.\\ 
     645 
     646   The process is the following: 
     647   \begin{description} 
     648   \item{step 1:} The top level is defined in the same way as the bottom level is defined. 
     649   \item{step 2:} The isolated grid point in the bathymetry are filled (as it is done in a domain without ice shelf) 
     650   \item{step 3:} The tools make sure, the top level is above or equal to the bottom level 
     651   \item{step 4:} If the water column at a U- or V- point is one wet cell wide, the ice shelf draft is adjusted. So the actual top cell become fully open and the new 
     652   top cell thickness is set to the minimum cell thickness allowed (following the same logic as for the bottom partial cell). This step is iterated 4 times to ensure the condition is fullfill along the 4 sides of the cell. 
     653   \end{description} 
     654 
     655   In case of steep slope and shallow water column, it likely that 2 cells are disconnected (bathymetry above its neigbourging ice shelf draft).  
     656   The option \np{ln_isfconnect}{ln\_isfconnect} allow the tool to force the connection between these 2 cells. 
     657   Some limiters in meter or levels on the digging allowed by the tool are available (respectively, \np{rn_zisfmax}{rn\_zisfmax} or \np{rn_kisfmax}{rn\_kisfmax}). 
     658   This will prevent the formation of subglacial lakes at the expense of long vertical pipe to connect cells at very different levels. 
     659 
     660   \subsection{Subglacial lakes} 
     661   Despite careful setting of your ice shelf draft and bathymetry input file as well as setting described in \autoref{subsec:zgrisf_isfd}, some situation are unavoidable. 
     662   For exemple if you setup your ice shelf draft and bathymetry to do ocean/ice sheet coupling,  
     663   you may decide to fill the whole antarctic with a bathymetry and an ice shelf draft value (ice/bedrock interface depth when grounded).  
     664   If you do so, the subglacial lakes will show up (Vostock for example). An other possibility is with coarse vertical resolution, some ice shelves could be cut in 2 parts:  
     665   one connected to the main ocean and an other one closed which can be considered as a subglacial sea be the model.\\ 
     666 
     667   The namelist option \np{ln_isfsubgl}{ln\_isfsubgl} allow you to remove theses subglacial lakes. 
     668   This may be useful for esthetical reason or for stability reasons: 
     669 
     670   \begin{description} 
     671   \item $\bullet$ In a subglacial lakes, in case of very weak circulation (often the case), the only heat flux is the conductive heat flux through the ice sheet.  
     672         This will lead to constant freezing until water reaches -20C.  
     673         This is one of the defitiency of the 3 equation melt formulation (for details on this formulation, see: \autoref{sec:isf}). 
     674   \item $\bullet$ In case of coupling with an ice sheet model,  
     675         the ssh in the subglacial lakes and the main ocean could be very different (ssh initial adjustement for example),  
     676         and so if for any reason both a connected at some point, the model is likely to fall over.\\ 
     677   \end{description} 
     678 
     679\section{Closed sea definition} 
     680\label{sec:clocfg} 
     681 
     682\begin{listing} 
     683  \caption{\forcode{&namclo}} 
     684  \label{lst:namdom_clo} 
     685  \begin{forlines} 
     686!----------------------------------------------------------------------- 
     687&namclo ! (closed sea : need ln_domclo = .true. in namcfg) 
     688!----------------------------------------------------------------------- 
     689   rn_lon_opnsea = -2.0     ! longitude seed of open ocean 
     690   rn_lat_opnsea = -2.0     ! latitude  seed of open ocean 
     691   nn_closea = 8           ! number of closed seas ( = 0; only the open_sea mask will be computed) 
     692   !                name   ! lon_src ! lat_src ! lon_trg ! lat_trg ! river mouth area   ! net evap/precip correction scheme ! radius tgt   ! id trg 
     693   !                       ! (degree)! (degree)! (degree)! (degree)! local/coast/global ! (glo/rnf/emp)                     !     (m)      ! 
     694   ! North American lakes 
     695   sn_lake(1) = 'superior' ,  -86.57 ,  47.30  , -66.49  , 50.45   , 'local'            , 'rnf'                             ,   550000.0 , 2     
     696   sn_lake(2) = 'michigan' ,  -87.06 ,  42.74  , -66.49  , 50.45   , 'local'            , 'rnf'                             ,   550000.0 , 2     
     697   sn_lake(3) = 'huron'    ,  -82.51 ,  44.74  , -66.49  , 50.45   , 'local'            , 'rnf'                             ,   550000.0 , 2     
     698   sn_lake(4) = 'erie'     ,  -81.13 ,  42.25  , -66.49  , 50.45   , 'local'            , 'rnf'                             ,   550000.0 , 2     
     699   sn_lake(5) = 'ontario'  ,  -77.72 ,  43.62  , -66.49  , 50.45   , 'local'            , 'rnf'                             ,   550000.0 , 2     
     700   ! African Lake 
     701   sn_lake(6) = 'victoria' ,   32.93 ,  -1.08  ,  30.44  , 31.37   , 'coast'            , 'emp'                             ,   100000.0 , 3     
     702   ! Asian Lakes 
     703   sn_lake(7) = 'caspian'  ,   50.0  ,  44.0   ,   0.0   ,  0.0    , 'global'           , 'glo'                             ,        0.0 , 1      
     704   sn_lake(8) = 'aral'     ,   60.0  ,  45.0   ,   0.0   ,  0.0    , 'global'           , 'glo'                             ,        0.0 , 1     
     705/ 
     706   \end{forlines} 
     707\end{listing} 
     708 
     709The options available to define the closed seas and how closed sea net fresh water input will be redistributed by NEMO are listed in \nam{clo}{dom_clo} (\texttt{DOMAINcfg} only). 
     710The individual definition of each closed sea is managed by \np{sn_lake}{sn\_lake}. In this fields the user needs to define:\\ 
     711   \begin{description} 
     712   \item $\bullet$    the name of the closed sea (print output purposes). 
     713   \item $\bullet$    the seed location to define the area of the closed sea (if seed on land because not present in this configuration, this closed sea will be ignored).\\ 
     714   \item $\bullet$    the seed location for the target area. 
     715   \item $\bullet$    the type of target area ('local','coast' or 'global'). See point 6 for definition of these cases. 
     716   \item $\bullet$    the type of redistribution scheme for the net fresh water flux over the closed sea (as a runoff in a target area, as emp in a target area, as emp globally). For the runoff case, if the net fwf is negative, it will be redistribut globally. 
     717   \item $\bullet$    the radius of the target area (not used for the 'global' case). So the target defined by a 'local' target area of a radius of 100km, for example, correspond to all the wet points within this radius. The coastal case will return only the coastal point within the specifid radius. 
     718   \item $\bullet$    the target id. This target id is used to group multiple lakes into the same river ouflow (Great Lakes for example). 
     719   \end{description} 
     720 
     721The closed sea module defines a number of masks in the \textit{domain\_cfg} output: 
     722   \begin{description} 
     723   \item[\textit{mask\_opensea}:] a mask of the main ocean without all the closed seas closed. This mask is defined by a flood filling algorithm with an initial seed (localisation defined by \np{rn_lon_opnsea}{rn\_lon\_opnsea} and \np{rn_lat_opnsea}{rn\_lat\_opnsea}). 
     724   \item[\textit{mask\_csglo}, \textit{mask\_csrnf}, \textit{mask\_csemp}:] a mask of all the closed seas defined in the namelist by \np{sn_lake}{sn\_lake} for each redistribution scheme. The total number of defined closed seas has to be defined in \np{nn_closea}{nn\_closea}. 
     725   \item[\textit{mask\_csgrpglo}, \textit{mask\_csgrprnf}, \textit{mask\_csgrpemp}:] a mask of all the closed seas and targets grouped by target id for each type of redistribution scheme. 
     726   \item[\textit{mask\_csundef}:] a mask of all the closed sea not defined in \np{sn_lake}{sn\_lake}. This will allows NEMO to mask them if needed or to inform the user of potential minor issues in its bathymetry. 
     727   \end{description} 
     728    
    592729\subinc{\input{../../global/epilogue}} 
    593730 
  • NEMO/trunk/doc/latex/NEMO/subfiles/chap_SBC.tex

    r14257 r14303  
    1515    \hline 
    1616    {\em  next} & {\em Simon M{\" u}ller} & {\em Update of \autoref{sec:SBC_TDE}; revision of \autoref{subsec:SBC_fwb}}\\[2mm] 
     17    {\em  next} & {\em Pierre Mathiot} & {\em update of the ice shelf section (2019 developments)}\\[2mm]   
    1718    {\em   4.0} & {\em ...} & {\em ...} \\ 
    1819    {\em   3.6} & {\em ...} & {\em ...} \\ 
     
    7273  (\np[=0..3]{nn_ice}{nn\_ice}), 
    7374\item the addition of river runoffs as surface freshwater fluxes or lateral inflow (\np[=.true.]{ln_rnf}{ln\_rnf}), 
    74 \item the addition of ice-shelf melting as lateral inflow (parameterisation) or 
    75   as fluxes applied at the land-ice ocean interface (\np[=.true.]{ln_isf}{ln\_isf}), 
    7675\item the addition of a freshwater flux adjustment in order to avoid a mean sea-level drift 
    7776  (\np[=0..2]{nn_fwb}{nn\_fwb}), 
     
    9796One of these is modification by icebergs (see \autoref{sec:SBC_ICB_icebergs}), 
    9897which act as drifting sources of fresh water. 
    99 Another example of modification is that due to the ice shelf melting/freezing (see \autoref{sec:SBC_isf}), 
    100 which provides additional sources of fresh water. 
    10198 
    10299%% ================================================================================================= 
     
    11811178 
    11821179%% ================================================================================================= 
    1183 \section[Ice shelf melting (\textit{sbcisf.F90})]{Ice shelf melting (\protect\mdl{sbcisf})} 
    1184 \label{sec:SBC_isf} 
     1180\section[Ice Shelf (ISF)]{Interaction with ice shelves (ISF)} 
     1181\label{sec:isf} 
    11851182 
    11861183\begin{listing} 
    1187 %  \nlst{namsbc_isf} 
    1188   \caption{\forcode{&namsbc_isf}} 
    1189   \label{lst:namsbc_isf} 
     1184  \nlst{namisf} 
     1185  \caption{\forcode{&namisf}} 
     1186  \label{lst:namisf} 
    11901187\end{listing} 
    11911188 
    1192 The namelist variable in \nam{sbc}{sbc}, \np{nn_isf}{nn\_isf}, controls the ice shelf representation. 
    1193 Description and result of sensitivity test to \np{nn_isf}{nn\_isf} are presented in \citet{mathiot.jenkins.ea_GMD17}. 
    1194 The different options are illustrated in \autoref{fig:SBC_isf}. 
    1195  
     1189The namelist variable in \nam{isf}{isf}, \np{ln_isf}{ln\_isf}, controls the ice shelf interactions: 
    11961190\begin{description} 
    1197   \item [{\np[=1]{nn_isf}{nn\_isf}}]: The ice shelf cavity is represented (\np[=.true.]{ln_isfcav}{ln\_isfcav} needed). 
    1198   The fwf and heat flux are depending of the local water properties. 
    1199  
    1200   Two different bulk formulae are available: 
     1191   \item $\bullet$ representation of the ice shelf/ocean melting/freezing for opened cavity (cav, \np{ln_isfcav_mlt}{ln\_isfcav\_mlt}). 
     1192   \item $\bullet$ parametrisation of the ice shelf/ocean melting/freezing for closed cavities (par, \np{ln_isfpar_mlt}{ln\_isfpar\_mlt}). 
     1193   \item $\bullet$ coupling with an ice sheet model (\np{ln_isfcpl}{ln\_isfcpl}). 
     1194\end{description} 
     1195 
     1196  \subsection{Ocean/Ice shelf fluxes in opened cavities} 
     1197 
     1198     \np{ln_isfcav_mlt}{ln\_isfcav\_mlt}\forcode{ = .true.} activates the ocean/ice shelf thermodynamics interactions at the ice shelf/ocean interface.  
     1199     If \np{ln_isfcav_mlt}\forcode{ = .false.}, thermodynamics interactions are desctivated but the ocean dynamics inside the cavity is still active. 
     1200     The logical flag \np{ln_isfcav}{ln\_isfcav} control whether or not the ice shelf cavities are closed. \np{ln_isfcav}{ln\_isfcav} is not defined in the namelist but in the domcfg.nc input file.\\ 
     1201 
     1202     3 options are available to represent to ice-shelf/ocean fluxes at the interface: 
     1203     \begin{description} 
     1204        \item[\np{cn_isfcav_mlt}\forcode{ = 'spe'}]: 
     1205        The fresh water flux is specified by a forcing fields \np{sn_isfcav_fwf}{sn\_isfcav\_fwf}. Convention of the input file is: positive toward the ocean (i.e. positive for melting and negative for freezing). 
     1206        The latent heat fluxes is derived from the fresh water flux.  
     1207        The heat content flux is derived from the fwf flux assuming a temperature set to the freezing point in the top boundary layer (\np{rn_htbl}{rn\_htbl}) 
     1208 
     1209        \item[\np{cn_isfcav_mlt}\forcode{ = 'oasis'}]: 
     1210        The \forcode{'oasis'} is a prototype of what could be a method to spread precipitation on Antarctic ice sheet as ice shelf melt inside the cavity when a coupled model Atmosphere/Ocean is used.  
     1211        It has not been tested and therefore the model will stop if you try to use it.  
     1212        Actions will be undertake in 2020 to build a comprehensive interface to do so for Greenland, Antarctic and ice shelf (cav), ice shelf (par), icebergs, subglacial runoff and runoff. 
     1213 
     1214        \item[\np{cn_isfcav_mlt}\forcode{ = '2eq'}]: 
     1215        The heat flux and the fresh water flux (negative for melting) resulting from ice shelf melting/freezing are parameterized following \citet{Grosfeld1997}.  
     1216        This formulation is based on a balance between the vertical diffusive heat flux across the ocean top boundary layer (\autoref{eq:ISOMIP1})  
     1217        and the latent heat due to melting/freezing (\autoref{eq:ISOMIP2}): 
     1218 
     1219        \begin{equation} 
     1220        \label{eq:ISOMIP1} 
     1221        \mathcal{Q}_h = \rho c_p \gamma (T_w - T_f) 
     1222        \end{equation} 
     1223        \begin{equation} 
     1224        \label{eq:ISOMIP2} 
     1225        q = \frac{-\mathcal{Q}_h}{L_f} 
     1226        \end{equation} 
     1227         
     1228        where $\mathcal{Q}_h$($W.m^{-2}$) is the heat flux,q($kg.s^{-1}m^{-2}$) the fresh-water flux,  
     1229        $L_f$ the specific latent heat, $T_w$ the temperature averaged over a boundary layer below the ice shelf (explained below),  
     1230        $T_f$ the freezing point using  the  pressure  at  the  ice  shelf  base  and  the  salinity  of the water in the boundary layer,  
     1231        and $\gamma$ the thermal exchange coefficient. 
     1232 
     1233        \item[\np{cn_isfcav_mlt}\forcode{ = '3eq'}]: 
     1234        For realistic studies, the heat and freshwater fluxes are parameterized following \citep{Jenkins2001}. This formulation is based on three equations:  
     1235        a balance between the vertical diffusive heat flux across the boundary layer  
     1236        , the latent heat due to melting/freezing of ice and the vertical diffusive heat flux into the ice shelf (\autoref{eq:3eq1});  
     1237        a balance between the vertical diffusive salt flux across the boundary layer and the salt source or sink represented by the melting/freezing (\autoref{eq:3eq2});  
     1238        and a linear equation for the freezing temperature of sea water (\autoref{eq:3eq3}, detailed of the linearisation coefficient in \citet{AsayDavis2016}): 
     1239 
     1240        \begin{equation} 
     1241        \label{eq:3eq1} 
     1242        c_p \rho \gamma_T (T_w-T_b) = -L_f q - \rho_i c_{p,i} \kappa \frac{T_s - T_b}{h_{isf}} 
     1243        \end{equation} 
     1244        \begin{equation} 
     1245        \label{eq:3eq2} 
     1246        \rho \gamma_S (S_w - S_b) = (S_i - S_b)q 
     1247        \end{equation} 
     1248        \begin{equation} 
     1249        \label{eq:3eq3} 
     1250        T_b = \lambda_1 S_b + \lambda_2 +\lambda_3 z_{isf} 
     1251        \end{equation} 
     1252 
     1253        where $T_b$ is the temperature at the interface, $S_b$ the salinity at the interface, $\gamma_T$ and $\gamma_S$ the exchange coefficients for temperature and salt, respectively,  
     1254        $S_i$ the salinity of the ice (assumed to be 0), $h_{isf}$ the ice shelf thickness, $z_{isf}$ the ice shelf draft, $\rho_i$ the density of the iceshelf,  
     1255        $c_{p,i}$ the specific heat capacity of the ice, $\kappa$ the thermal diffusivity of the ice  
     1256        and $T_s$ the atmospheric surface temperature (at the ice/air interface, assumed to be -20C).  
     1257        The Liquidus slope ($\lambda_1$), the liquidus intercept ($\lambda_2$) and the Liquidus pressure coefficient ($\lambda_3$)  
     1258        for TEOS80 and TEOS10 are described in \citep{AsayDavis2016} and in \citep{Jourdain2017}. 
     1259        The linear system formed by \autoref{eq:3eq1}, \autoref{eq:3eq2} and the linearised equation for the freezing temperature of sea water (\autoref{eq:3eq3}) can be solved for $S_b$ or $T_b$.  
     1260        Afterward, the freshwater flux ($q$) and the heat flux ($\mathcal{Q}_h$) can be computed. 
     1261 
     1262     \end{description} 
     1263 
     1264     \begin{table}[h] 
     1265        \centering 
     1266        \caption{Description of the parameters hard coded into the ISF module} 
     1267        \label{tab:isf} 
     1268        \begin{tabular}{|l|l|l|l|} 
     1269        \hline 
     1270        Symbol    & Description               & Value              & Unit               \\ 
     1271        \hline 
     1272        $C_p$     & Ocean specific heat       & 3992               & $J.kg^{-1}.K^{-1}$ \\ 
     1273        $L_f$     & Ice latent heat of fusion & $3.34 \times 10^5$ & $J.kg^{-1}$        \\ 
     1274        $C_{p,i}$ & Ice specific heat         & 2000               & $J.kg^{-1}.K^{-1}$ \\ 
     1275        $\kappa$  & Heat diffusivity          & $1.54 \times 10^{-6}$& $m^2.s^{-1}$     \\ 
     1276        $\rho_i$  & Ice density               & 920                & $kg.m^3$           \\ 
     1277        \hline 
     1278        \end{tabular} 
     1279     \end{table} 
     1280 
     1281     Temperature and salinity used to compute the fluxes in \autoref{eq:ISOMIP1}, \autoref{eq:3eq1} and \autoref{eq:3eq2} are the average temperature in the top boundary layer \citep{losch_JGR08}.  
     1282     Its thickness is defined by \np{rn_htbl}{rn\_htbl}. 
     1283     The fluxes and friction velocity are computed using the mean temperature, salinity and velocity in the first \np{rn_htbl}{rn\_htbl} m. 
     1284     Then, the fluxes are spread over the same thickness (ie over one or several cells). 
     1285     If \np{rn_htbl}{rn\_htbl} is larger than top $e_{3}t$, there is no more direct feedback between the freezing point at the interface and the top cell temperature. 
     1286     This can lead to super-cool temperature in the top cell under melting condition. 
     1287     If \np{rn_htbl}{rn\_htbl} smaller than top $e_{3}t$, the top boundary layer thickness is set to the top cell thickness.\\ 
     1288 
     1289     Each melt formula (\np{cn_isfcav_mlt}\forcode{ = '3eq'} or \np{cn_isfcav_mlt}\forcode{ = '2eq'}) depends on an exchange coeficient ($\Gamma^{T,S}$) between the ocean and the ice. 
     1290     Below, the exchange coeficient $\Gamma^{T}$ and $\Gamma^{S}$ are respectively defined by \np{rn_gammat0}{rn\_gammat0} and \np{rn_gammas0}{rn\_gammas0}.  
     1291     There are 3 different ways to compute the exchange velocity: 
     1292 
     1293     \begin{description} 
     1294        \item[\np{cn_gammablk}\forcode{='spe'}]: 
     1295        The salt and heat exchange coefficients are constant and defined by: 
     1296\[ 
     1297\gamma^{T} = \Gamma^{T} 
     1298\] 
     1299\[ 
     1300\gamma^{S} = \Gamma^{S} 
     1301\]  
     1302        This is the recommended formulation for ISOMIP. 
     1303 
     1304   \item[\np{cn_gammablk}\forcode{='vel'}]: 
     1305        The salt and heat exchange coefficients are velocity dependent and defined as 
     1306\[ 
     1307\gamma^{T} = \Gamma^{T} \times u_{*}  
     1308\] 
     1309\[ 
     1310\gamma^{S} = \Gamma^{S} \times u_{*} 
     1311\] 
     1312        where $u_{*}$ is the friction velocity in the top boundary layer (ie first \np{rn_htbl}{rn\_htbl} meters). 
     1313        See \citet{jenkins.nicholls.ea_JPO10} for all the details on this formulation. It is the recommended formulation for realistic application and ISOMIP+/MISOMIP configuration. 
     1314 
     1315   \item[\np{cn_gammablk}\forcode{'vel\_stab'}]: 
     1316        The salt and heat exchange coefficients are velocity and stability dependent and defined as: 
     1317\[ 
     1318\gamma^{T,S} = \frac{u_{*}}{\Gamma_{Turb} + \Gamma^{T,S}_{Mole}}  
     1319\] 
     1320        where $u_{*}$ is the friction velocity in the top boundary layer (ie first \np{rn_tbl}{rn\_htbl} meters), 
     1321        $\Gamma_{Turb}$ the contribution of the ocean stability and 
     1322        $\Gamma^{T,S}_{Mole}$ the contribution of the molecular diffusion. 
     1323        See \citet{holland.jenkins_JPO99} for all the details on this formulation.  
     1324        This formulation has not been extensively tested in NEMO (not recommended). 
     1325     \end{description} 
     1326 
     1327\subsection{Ocean/Ice shelf fluxes in parametrised cavities} 
    12011328 
    12021329  \begin{description} 
    1203   \item [{\np[=1]{nn_isfblk}{nn\_isfblk}}]: The melt rate is based on a balance between the upward ocean heat flux and 
    1204     the latent heat flux at the ice shelf base. A complete description is available in \citet{hunter_trpt06}. 
    1205   \item [{\np[=2]{nn_isfblk}{nn\_isfblk}}]: The melt rate and the heat flux are based on a 3 equations formulation 
    1206     (a heat flux budget at the ice base, a salt flux budget at the ice base and a linearised freezing point temperature equation). 
    1207     A complete description is available in \citet{jenkins_JGR91}. 
     1330 
     1331     \item[\np{cn_isfpar_mlt}\forcode{ = 'bg03'}]: 
     1332     The ice shelf cavities are not represented. 
     1333     The fwf and heat flux are computed using the \citet{beckmann.goosse_OM03} parameterisation of isf melting. 
     1334     The fluxes are distributed along the ice shelf edge between the depth of the average grounding line (GL) 
     1335     (\np{sn_isfpar_zmax}{sn\_isfpar\_zmax}) and the base of the ice shelf along the calving front 
     1336     (\np{sn_isfpar_zmin}{sn\_isfpar\_zmin}) as in (\np{cn_isfpar_mlt}\forcode{ = 'spe'}). 
     1337     The effective melting length (\np{sn_isfpar_Leff}{sn\_isfpar\_Leff}) is read from a file. 
     1338     This parametrisation has not been tested since a while and based on \citet{Favier2019},  
     1339     this parametrisation should probably not be used. 
     1340 
     1341     \item[\np{cn_isfpar_mlt}\forcode{ = 'spe'}]: 
     1342     The ice shelf cavity is not represented. 
     1343     The fwf (\np{sn_isfpar_fwf}{sn\_isfpar\_fwf}) is prescribed and distributed along the ice shelf edge between 
     1344     the depth of the average grounding line (GL) (\np{sn_isfpar_zmax}{sn\_isfpar\_zmax}) and 
     1345     the base of the ice shelf along the calving front (\np{sn_isfpar_zmin}{sn\_isfpar\_min}). Convention of the input file is positive toward the ocean (i.e. positive for melting and negative for freezing). 
     1346     The heat flux ($Q_h$) is computed as $Q_h = fwf \times L_f$. 
     1347 
     1348     \item[\np{cn_isfpar_mlt}\forcode{ = 'oasis'}]: 
     1349     The \forcode{'oasis'} is a prototype of what could be a method to spread precipitation on Antarctic ice sheet as ice shelf melt inside the cavity when a coupled model Atmosphere/Ocean is used.  
     1350     It has not been tested and therefore the model will stop if you try to use it.  
     1351     Action will be undertake in 2020 to build a comprehensive interface to do so for Greenland, Antarctic and ice shelf (cav), ice shelf (par), icebergs, subglacial runoff and runoff. 
     1352 
    12081353  \end{description} 
    12091354 
    1210   Temperature and salinity used to compute the melt are the average temperature in the top boundary layer \citet{losch_JGR08}. 
    1211   Its thickness is defined by \np{rn_hisf_tbl}{rn\_hisf\_tbl}. 
    1212   The fluxes and friction velocity are computed using the mean temperature, salinity and velocity in the the first \np{rn_hisf_tbl}{rn\_hisf\_tbl} m. 
    1213   Then, the fluxes are spread over the same thickness (ie over one or several cells). 
    1214   If \np{rn_hisf_tbl}{rn\_hisf\_tbl} larger than top $e_{3}t$, there is no more feedback between the freezing point at the interface and the the top cell temperature. 
    1215   This can lead to super-cool temperature in the top cell under melting condition. 
    1216   If \np{rn_hisf_tbl}{rn\_hisf\_tbl} smaller than top $e_{3}t$, the top boundary layer thickness is set to the top cell thickness.\\ 
    1217  
    1218   Each melt bulk formula depends on a exchange coeficient ($\Gamma^{T,S}$) between the ocean and the ice. 
    1219   There are 3 different ways to compute the exchange coeficient: 
    1220   \begin{description} 
    1221   \item [{\np[=0]{nn_gammablk}{nn\_gammablk}}]: The salt and heat exchange coefficients are constant and defined by \np{rn_gammas0}{rn\_gammas0} and \np{rn_gammat0}{rn\_gammat0}. 
    1222     \begin{gather*} 
    1223        % \label{eq:SBC_isf_gamma_iso} 
    1224       \gamma^{T} = rn\_gammat0 \\ 
    1225       \gamma^{S} = rn\_gammas0 
    1226     \end{gather*} 
    1227     This is the recommended formulation for ISOMIP. 
    1228   \item [{\np[=1]{nn_gammablk}{nn\_gammablk}}]: The salt and heat exchange coefficients are velocity dependent and defined as 
    1229     \begin{gather*} 
    1230       \gamma^{T} = rn\_gammat0 \times u_{*} \\ 
    1231       \gamma^{S} = rn\_gammas0 \times u_{*} 
    1232     \end{gather*} 
    1233     where $u_{*}$ is the friction velocity in the top boundary layer (ie first \np{rn_hisf_tbl}{rn\_hisf\_tbl} meters). 
    1234     See \citet{jenkins.nicholls.ea_JPO10} for all the details on this formulation. It is the recommended formulation for realistic application. 
    1235   \item [{\np[=2]{nn_gammablk}{nn\_gammablk}}]: The salt and heat exchange coefficients are velocity and stability dependent and defined as: 
    1236     \[ 
    1237       \gamma^{T,S} = \frac{u_{*}}{\Gamma_{Turb} + \Gamma^{T,S}_{Mole}} 
    1238     \] 
    1239     where $u_{*}$ is the friction velocity in the top boundary layer (ie first \np{rn_hisf_tbl}{rn\_hisf\_tbl} meters), 
    1240     $\Gamma_{Turb}$ the contribution of the ocean stability and 
    1241     $\Gamma^{T,S}_{Mole}$ the contribution of the molecular diffusion. 
    1242     See \citet{holland.jenkins_JPO99} for all the details on this formulation. 
    1243     This formulation has not been extensively tested in \NEMO\ (not recommended). 
    1244   \end{description} 
    1245 \item [{\np[=2]{nn_isf}{nn\_isf}}]: The ice shelf cavity is not represented. 
    1246   The fwf and heat flux are computed using the \citet{beckmann.goosse_OM03} parameterisation of isf melting. 
    1247   The fluxes are distributed along the ice shelf edge between the depth of the average grounding line (GL) 
    1248   (\np{sn_depmax_isf}{sn\_depmax\_isf}) and the base of the ice shelf along the calving front 
    1249   (\np{sn_depmin_isf}{sn\_depmin\_isf}) as in (\np[=3]{nn_isf}{nn\_isf}). 
    1250   The effective melting length (\np{sn_Leff_isf}{sn\_Leff\_isf}) is read from a file. 
    1251 \item [{\np[=3]{nn_isf}{nn\_isf}}]: The ice shelf cavity is not represented. 
    1252   The fwf (\np{sn_rnfisf}{sn\_rnfisf}) is prescribed and distributed along the ice shelf edge between 
    1253   the depth of the average grounding line (GL) (\np{sn_depmax_isf}{sn\_depmax\_isf}) and 
    1254   the base of the ice shelf along the calving front (\np{sn_depmin_isf}{sn\_depmin\_isf}). 
    1255   The heat flux ($Q_h$) is computed as $Q_h = fwf \times L_f$. 
    1256 \item [{\np[=4]{nn_isf}{nn\_isf}}]: The ice shelf cavity is opened (\np[=.true.]{ln_isfcav}{ln\_isfcav} needed). 
    1257   However, the fwf is not computed but specified from file \np{sn_fwfisf}{sn\_fwfisf}). 
    1258   The heat flux ($Q_h$) is computed as $Q_h = fwf \times L_f$. 
    1259   As in \np[=1]{nn_isf}{nn\_isf}, the fluxes are spread over the top boundary layer thickness (\np{rn_hisf_tbl}{rn\_hisf\_tbl}) 
    1260 \end{description} 
    1261  
    1262 $\bullet$ \np[=1]{nn_isf}{nn\_isf} and \np[=2]{nn_isf}{nn\_isf} compute a melt rate based on 
     1355\np{cn_isfcav_mlt}\forcode{ = '2eq'}, \np{cn_isfcav_mlt}\forcode{ = '3eq'} and \np{cn_isfpar_mlt}\forcode{ = 'bg03'} compute a melt rate based on 
    12631356the water mass properties, ocean velocities and depth. 
    1264 This flux is thus highly dependent of the model resolution (horizontal and vertical), 
    1265 realism of the water masses onto the shelf ...\\ 
    1266  
    1267 $\bullet$ \np[=3]{nn_isf}{nn\_isf} and \np[=4]{nn_isf}{nn\_isf} read the melt rate from a file. 
     1357The resulting fluxes are thus highly dependent of the model resolution (horizontal and vertical) and  
     1358realism of the water masses onto the shelf.\\ 
     1359 
     1360\np{cn_isfcav_mlt}\forcode{ = 'spe'} and \np{cn_isfpar_mlt}\forcode{ = 'spe'} read the melt rate from a file. 
    12681361You have total control of the fwf forcing. 
    12691362This can be useful if the water masses on the shelf are not realistic or 
    12701363the resolution (horizontal/vertical) are too coarse to have realistic melting or 
    1271 for studies where you need to control your heat and fw input.\\ 
    1272  
    1273 The ice shelf melt is implemented as a volume flux as for the runoff. 
    1274 The fw addition due to the ice shelf melting is, at each relevant depth level, added to 
    1275 the horizontal divergence (\textit{hdivn}) in the subroutine \rou{sbc\_isf\_div}, called from \mdl{divhor}. 
    1276 See \autoref{sec:SBC_rnf} for all the details about the divergence correction. 
     1364for studies where you need to control your heat and fw input.  
     1365However, if your forcing is not consistent with the dynamics below you can reach unrealistic low water temperature.\\ 
     1366 
     1367The ice shelf fwf is implemented as a volume flux as for the runoff. 
     1368The fwf addition due to the ice shelf melting is, at each relevant depth level, added to 
     1369the horizontal divergence (\textit{hdivn}) in the subroutine \rou{isf\_hdiv}, called from \mdl{divhor}. 
     1370See the runoff section \autoref{sec:SBC_rnf} for all the details about the divergence correction.\\ 
     1371 
     1372Description and result of sensitivity tests to \np{ln_isfcav_mlt}{ln\_isfcav\_mlt} and \np{ln_isfpar_mlt}{ln\_isfpar\_mlt} are presented in \citet{mathiot.jenkins.ea_GMD17}.  
     1373The different options are illustrated in \autoref{fig:ISF}. 
    12771374 
    12781375\begin{figure}[!t] 
    12791376  \centering 
    1280   \includegraphics[width=0.66\textwidth]{SBC_isf} 
     1377  \includegraphics[width=0.66\textwidth]{SBC_isf_v4.2} 
    12811378  \caption[Ice shelf location and fresh water flux definition]{ 
    12821379    Illustration of the location where the fwf is injected and 
    1283     whether or not the fwf is interactif or not depending of \protect\np{nn_isf}{nn\_isf}.} 
    1284   \label{fig:SBC_isf} 
     1380    whether or not the fwf is interactive or not.} 
     1381  \label{fig:ISF} 
    12851382\end{figure} 
    12861383 
    1287 %% ================================================================================================= 
    1288 \section{Ice sheet coupling} 
    1289 \label{sec:SBC_iscpl} 
    1290  
    1291 \begin{listing} 
    1292 %  \nlst{namsbc_iscpl} 
    1293   \caption{\forcode{&namsbc_iscpl}} 
    1294   \label{lst:namsbc_iscpl} 
    1295 \end{listing} 
     1384\subsection{Available outputs} 
     1385The following outputs are availables via XIOS: 
     1386\begin{description} 
     1387   \item[for parametrised cavities]: 
     1388      \begin{xmllines} 
     1389 <field id="isftfrz_par"     long_name="freezing point temperature in the parametrization boundary layer" unit="degC"     /> 
     1390 <field id="fwfisf_par"      long_name="Ice shelf melt rate"                           unit="kg/m2/s"  /> 
     1391 <field id="qoceisf_par"     long_name="Ice shelf ocean  heat flux"                    unit="W/m2"     /> 
     1392 <field id="qlatisf_par"     long_name="Ice shelf latent heat flux"                    unit="W/m2"     /> 
     1393 <field id="qhcisf_par"      long_name="Ice shelf heat content flux of injected water" unit="W/m2"     /> 
     1394 <field id="fwfisf3d_par"    long_name="Ice shelf melt rate"                           unit="kg/m2/s"  grid_ref="grid_T_3D" /> 
     1395 <field id="qoceisf3d_par"   long_name="Ice shelf ocean  heat flux"                    unit="W/m2"     grid_ref="grid_T_3D" /> 
     1396 <field id="qlatisf3d_par"   long_name="Ice shelf latent heat flux"                    unit="W/m2"     grid_ref="grid_T_3D" /> 
     1397 <field id="qhcisf3d_par"    long_name="Ice shelf heat content flux of injected water" unit="W/m2"     grid_ref="grid_T_3D" /> 
     1398 <field id="ttbl_par"        long_name="temperature in the parametrisation boundary layer" unit="degC" /> 
     1399 <field id="isfthermald_par" long_name="thermal driving of ice shelf melting"          unit="degC"     /> 
     1400      \end{xmllines} 
     1401   \item[for open cavities]: 
     1402      \begin{xmllines} 
     1403 <field id="isftfrz_cav"     long_name="freezing point temperature at ocean/isf interface"                unit="degC"     /> 
     1404 <field id="fwfisf_cav"      long_name="Ice shelf melt rate"                           unit="kg/m2/s"  /> 
     1405 <field id="qoceisf_cav"     long_name="Ice shelf ocean  heat flux"                    unit="W/m2"     /> 
     1406 <field id="qlatisf_cav"     long_name="Ice shelf latent heat flux"                    unit="W/m2"     /> 
     1407 <field id="qhcisf_cav"      long_name="Ice shelf heat content flux of injected water" unit="W/m2"     /> 
     1408 <field id="fwfisf3d_cav"    long_name="Ice shelf melt rate"                           unit="kg/m2/s"  grid_ref="grid_T_3D" /> 
     1409 <field id="qoceisf3d_cav"   long_name="Ice shelf ocean  heat flux"                    unit="W/m2"     grid_ref="grid_T_3D" /> 
     1410 <field id="qlatisf3d_cav"   long_name="Ice shelf latent heat flux"                    unit="W/m2"     grid_ref="grid_T_3D" /> 
     1411 <field id="qhcisf3d_cav"    long_name="Ice shelf heat content flux of injected water" unit="W/m2"     grid_ref="grid_T_3D" /> 
     1412 <field id="ttbl_cav"        long_name="temperature in Losch tbl"                      unit="degC"     /> 
     1413 <field id="isfthermald_cav" long_name="thermal driving of ice shelf melting"          unit="degC"     /> 
     1414 <field id="isfgammat"       long_name="Ice shelf heat-transfert velocity"             unit="m/s"      /> 
     1415 <field id="isfgammas"       long_name="Ice shelf salt-transfert velocity"             unit="m/s"      /> 
     1416 <field id="stbl"            long_name="salinity in the Losh tbl"                      unit="1e-3"     /> 
     1417 <field id="utbl"            long_name="zonal current in the Losh tbl at T point"      unit="m/s"      /> 
     1418 <field id="vtbl"            long_name="merid current in the Losh tbl at T point"      unit="m/s"      /> 
     1419 <field id="isfustar"        long_name="ustar at T point used in ice shelf melting"    unit="m/s"      /> 
     1420 <field id="qconisf"         long_name="Conductive heat flux through the ice shelf"    unit="W/m2"     /> 
     1421      \end{xmllines} 
     1422\end{description} 
     1423 
     1424%% ================================================================================================= 
     1425\subsection{Ice sheet coupling} 
     1426\label{subsec:ISF_iscpl} 
    12961427 
    12971428Ice sheet/ocean coupling is done through file exchange at the restart step. 
    1298 At each restart step: 
    1299  
    1300 \begin{enumerate} 
    1301 \item the ice sheet model send a new bathymetry and ice shelf draft netcdf file. 
    1302 \item a new domcfg.nc file is built using the DOMAINcfg tools. 
    1303 \item \NEMO\ run for a specific period and output the average melt rate over the period. 
    1304 \item the ice sheet model run using the melt rate outputed in step 4. 
    1305 \item go back to 1. 
    1306 \end{enumerate} 
    1307  
    1308 If \np[=.true.]{ln_iscpl}{ln\_iscpl}, the isf draft is assume to be different at each restart step with 
     1429At each restart step, the procedure is this one: 
     1430 
     1431\begin{description} 
     1432\item[Step 1]: the ice sheet model send a new bathymetry and ice shelf draft netcdf file. 
     1433\item[Step 2]: a new domcfg.nc file is built using the DOMAINcfg tools. 
     1434\item[Step 3]: NEMO run for a specific period and output the average melt rate over the period. 
     1435\item[Step 4]: the ice sheet model run using the melt rate outputed in step 3. 
     1436\item[Step 5]: go back to 1. 
     1437\end{description} 
     1438 
     1439If \np{ln_iscpl}\forcode{ = .true.}, the isf draft is assume to be different at each restart step with 
    13091440potentially some new wet/dry cells due to the ice sheet dynamics/thermodynamics. 
    1310 The wetting and drying scheme applied on the restart is very simple and described below for the 6 different possible cases: 
     1441The wetting and drying scheme, applied on the restart, is very simple. The 6 different possible cases for the tracer and ssh are: 
    13111442 
    13121443\begin{description} 
    1313 \item [Thin a cell down]: T/S/ssh are unchanged and U/V in the top cell are corrected to keep the barotropic transport (bt) constant 
    1314   ($bt_b=bt_n$). 
    1315 \item [Enlarge  a cell]: See case "Thin a cell down" 
    1316 \item [Dry a cell]: mask, T/S, U/V and ssh are set to 0. 
    1317   Furthermore, U/V into the water column are modified to satisfy ($bt_b=bt_n$). 
    1318 \item [Wet a cell]: mask is set to 1, T/S is extrapolated from neighbours, $ssh_n = ssh_b$ and U/V set to 0. 
    1319   If no neighbours, T/S is extrapolated from old top cell value. 
    1320   If no neighbours along i,j and k (both previous test failed), T/S/U/V/ssh and mask are set to 0. 
    1321 \item [Dry a column]: mask, T/S, U/V are set to 0 everywhere in the column and ssh set to 0. 
    1322 \item [Wet a column]: set mask to 1, T/S is extrapolated from neighbours, ssh is extrapolated from neighbours and U/V set to 0. 
    1323   If no neighbour, T/S/U/V and mask set to 0. 
     1444   \item[Thin a cell]: 
     1445   T/S/ssh are unchanged. 
     1446 
     1447   \item[Enlarge  a cell]: 
     1448   See case "Thin a cell down" 
     1449 
     1450   \item[Dry a cell]: 
     1451   Mask, T/S, U/V and ssh are set to 0. 
     1452 
     1453   \item[Wet a cell]:  
     1454   Mask is set to 1, T/S is extrapolated from neighbours, $ssh_n = ssh_b$. 
     1455   If no neighbours, T/S is extrapolated from old top cell value.  
     1456   If no neighbours along i,j and k (both previous tests failed), T/S/ssh and mask are set to 0. 
     1457 
     1458   \item[Dry a column]: 
     1459   mask, T/S and ssh are set to 0. 
     1460 
     1461   \item[Wet a column]: 
     1462   set mask to 1, T/S/ssh are extrapolated from neighbours. 
     1463   If no neighbour, T/S/ssh and mask set to 0. 
    13241464\end{description} 
     1465 
     1466The method described above will strongly affect the barotropic transport under an ice shelf when the geometry change. 
     1467In order to keep the model stable, an adjustment of the dynamics at the initialisation after the coupling step is needed.  
     1468The idea behind this is to keep $\pd[\eta]{t}$ as it should be without change in geometry at the initialisation.  
     1469This will prevent any strong velocity due to large pressure gradient.  
     1470To do so, we correct the horizontal divergence before $\pd[\eta]{t}$ is computed in the first time step.\\ 
    13251471 
    13261472Furthermore, as the before and now fields are not compatible (modification of the geometry), 
     
    13291475The horizontal extrapolation to fill new cell with realistic value is called \np{nn_drown}{nn\_drown} times. 
    13301476It means that if the grounding line retreat by more than \np{nn_drown}{nn\_drown} cells between 2 coupling steps, 
    1331 the code will be unable to fill all the new wet cells properly. 
     1477the code will be unable to fill all the new wet cells properly and the model is likely to blow up at the initialisation. 
    13321478The default number is set up for the MISOMIP idealised experiments. 
    13331479This coupling procedure is able to take into account grounding line and calving front migration. 
    1334 However, it is a non-conservative processe. 
     1480However, it is a non-conservative proccess.  
    13351481This could lead to a trend in heat/salt content and volume.\\ 
    13361482 
    13371483In order to remove the trend and keep the conservation level as close to 0 as possible, 
    1338 a simple conservation scheme is available with \np[=.true.]{ln_hsb}{ln\_hsb}. 
    1339 The heat/salt/vol. gain/loss is diagnosed, as well as the location. 
    1340 A correction increment is computed and apply each time step during the next \np{rn_fiscpl}{rn\_fiscpl} time steps. 
    1341 For safety, it is advised to set \np{rn_fiscpl}{rn\_fiscpl} equal to the coupling period (smallest increment possible). 
    1342 The corrective increment is apply into the cell itself (if it is a wet cell), the neigbouring cells or the closest wet cell (if the cell is now dry). 
     1484a simple conservation scheme is available with \np{ln_isfcpl_cons}\forcode{ = .true.}. 
     1485The heat/salt/vol. gain/loss are diagnosed, as well as the location. 
     1486A correction increment is computed and applied each time step during the model run. 
     1487The corrective increment are applied into the cells itself (if it is a wet cell), the neigbouring cells or the closest wet cell (if the cell is now dry). 
    13431488 
    13441489%% ================================================================================================= 
     
    13881533which are assumed to propagate with their larger parent and thus delay fluxing into the ocean. 
    13891534Melt water (and other variables on the configuration grid) are written into the main \NEMO\ model output files. 
     1535 
     1536By default, iceberg thermodynamic and dynamic are computed using ocean surface variable (sst, ssu, ssv) and the icebergs are not sensible to the bathymetry (only to land) whatever the iceberg draft.  
     1537\citet{Merino_OM2016} developed an option to use vertical profiles of ocean currents and temperature instead (\np{ln_M2016}{ln\_M2016}). 
     1538Full details on the sensitivity to this parameter in done in \citet{Merino_OM2016}.  
     1539If \np{ln_M2016}{ln\_M2016} activated, \np{ln_icb_grd}{ln\_icb\_grd} activate (or not) an option to prevent thick icebergs to move across shallow bank (ie shallower than the iceberg draft). 
     1540This option need to be used with care as it could required to either change the distribution to prevent generation of icebergs with draft larger than the bathymetry  
     1541or to build a variable \forcode{maxclass} to prevent NEMO filling the icebergs classes too thick for the local bathymetry. 
    13901542 
    13911543Extensive diagnostics can be produced. 
  • NEMO/trunk/doc/latex/NEMO/subfiles/chap_TRA.tex

    r14257 r14303  
    733733  (see \autoref{sec:SBC_rnf} for further detail of how it acts on temperature and salinity tendencies) 
    734734\item [\textit{fwfisf}] The mass flux associated with ice shelf melt, 
    735   (see \autoref{sec:SBC_isf} for further details on how the ice shelf melt is computed and applied). 
     735  (see \autoref{sec:isf} for further details on how the ice shelf melt is computed and applied). 
    736736\end{labeling} 
    737737 
  • NEMO/trunk/doc/latex/NEMO/subfiles/chap_misc.tex

    r14257 r14303  
    1414    Release & Author(s) & Modifications \\ 
    1515    \hline 
     16    {\em   X.X} & {\em Pierre Mathiot} & {update of the closed sea section} 
    1617    {\em   4.0} & {\em ...} & {\em ...} \\ 
    1718    {\em   3.6} & {\em ...} & {\em ...} \\ 
     
    107108\end{figure} 
    108109 
    109 \begin{figure}[!tbp] 
    110   \centering 
    111   \includegraphics[width=0.66\textwidth]{MISC_closea_mask_example} 
    112   \caption[Mask fields for the \protect\mdl{closea} module]{ 
    113     Example of mask fields for the \protect\mdl{closea} module. 
    114     \textit{Left}: a closea\_mask field; 
    115     \textit{Right}: a closea\_mask\_rnf field. 
    116     In this example, if \protect\np{ln_closea}{ln\_closea} is set to \forcode{.true.}, 
    117     the mean freshwater flux over each of the American Great Lakes will be set to zero, 
    118     and the total residual for all the lakes, if negative, will be put into 
    119     the St Laurence Seaway in the area shown.} 
    120   \label{fig:MISC_closea_mask_example} 
    121 \end{figure} 
    122  
    123110%% ================================================================================================= 
    124111\section[Closed seas (\textit{closea.F90})]{Closed seas (\protect\mdl{closea})} 
    125112\label{sec:MISC_closea} 
     113 
     114\begin{listing} 
     115  \nlst{namclo} 
     116  \caption{\forcode{&namclo}} 
     117  \label{lst:namclo} 
     118\end{listing} 
    126119 
    127120Some configurations include inland seas and lakes as ocean 
     
    136129to zero and put the residual flux into the ocean. 
    137130 
    138 Prior to \NEMO\ 4 the locations of inland seas and lakes was set via 
    139 hardcoded indices for various ORCA configurations. From \NEMO\ 4 onwards 
    140 the inland seas and lakes are defined using mask fields in the 
    141 domain configuration file. The options are as follows. 
    142  
    143 \begin{enumerate} 
    144 \item {{\bfseries No ``closea\_mask'' field is included in domain configuration 
    145   file.} In this case the closea module does nothing.} 
    146  
    147 \item {{\bfseries A field called closea\_mask is included in the domain 
    148 configuration file and ln\_closea=.false. in namelist namcfg.} In this 
    149 case the inland seas defined by the closea\_mask field are filled in 
    150 (turned to land points) at run time. That is every point in 
    151 closea\_mask that is nonzero is set to be a land point.} 
    152  
    153 \item {{\bfseries A field called closea\_mask is included in the domain 
    154 configuration file and ln\_closea=.true. in namelist namcfg.} Each 
    155 inland sea or group of inland seas is set to a positive integer value 
    156 in the closea\_mask field (see \autoref{fig:MISC_closea_mask_example} 
    157 for an example). The net surface flux over each inland sea or group of 
     131The inland seas and lakes are defined using mask fields in the 
     132domain configuration file. Special treatment of the closed sea (redistribution of net freshwater or mask those), are defined in \autoref{lst:namclo} and 
     133can be trigger by \np{ln_closea}{ln\_closea}\forcode{=.true.} in namelist namcfg. 
     134 
     135The options available are the following: 
     136\begin{description} 
     137\item[\np{ln_maskcs}{ln\_maskcs}\forcode{ = .true.}] All the closed seas are masked using \textit{mask\_opensea} variable. 
     138\item[\np{ln_maskcs}{ln\_maskcs}\forcode{ = .false.}] The net surface flux over each inland sea or group of 
    158139inland seas is set to zero each timestep and the residual flux is 
    159 distributed over the global ocean (ie. all ocean points where 
    160 closea\_mask is zero).} 
    161  
    162 \item {{\bfseries Fields called closea\_mask and closea\_mask\_rnf are 
    163 included in the domain configuration file and ln\_closea=.true. in 
    164 namelist namcfg.} This option works as for option 3, except that if 
    165 the net surface flux over an inland sea is negative (net 
    166 precipitation) it is put into the ocean at specified runoff points. A 
    167 net positive surface flux (net evaporation) is still spread over the 
    168 global ocean. The mapping from inland seas to runoff points is defined 
    169 by the closea\_mask\_rnf field. Each mapping is defined by a positive 
    170 integer value for the inland sea(s) and the corresponding runoff 
    171 points. An example is given in 
    172 \autoref{fig:MISC_closea_mask_example}. If no mapping is provided for a 
    173 particular inland sea then the residual is spread over the global 
    174 ocean.} 
    175  
    176 \item {{\bfseries Fields called closea\_mask and closea\_mask\_emp are 
    177 included in the domain configuration file and ln\_closea=.true. in 
    178 namelist namcfg.} This option works the same as option 4 except that 
    179 the nonzero net surface flux is sent to the ocean at the specified 
    180 runoff points regardless of whether it is positive or negative. The 
    181 mapping from inland seas to runoff points in this case is defined by 
    182 the closea\_mask\_emp field.} 
    183 \end{enumerate} 
    184  
    185 There is a python routine to create the closea\_mask fields and append 
    186 them to the domain configuration file in the utils/tools/DOMAINcfg directory. 
     140distributed over a target area. 
     141\end{description} 
     142 
     143When \np{ln_maskcs}{ln\_maskcs}\forcode{ = .false.},  
     1443 options are available for the redistribution (set up of these options is done in the tool DOMAINcfg): 
     145\begin{description}[font=$\bullet$ ] 
     146\item[ glo]: The residual flux is redistributed globally. 
     147\item[ emp]: The residual flux is redistributed as emp in a river outflow. 
     148\item[ rnf]: The residual flux is redistributed as rnf in a river outflow if negative. If there is a net evaporation, the residual flux is redistributed globally. 
     149\end{description} 
     150 
     151For each case, 2 masks are needed (\autoref{fig:MISC_closea_mask_example}):  
     152\begin{description} 
     153\item $\bullet$ one describing the 'sources' (ie the closed seas concerned by each options) called \textit{mask\_csglo}, \textit{mask\_csrnf}, \textit{mask\_csemp}.  
     154\item $\bullet$ one describing each group of inland seas (the Great Lakes for example) and the target area (river outflow or world ocean) for each group of inland seas (St Laurence for the Great Lakes for example) called 
     155\textit{mask\_csgrpglo}, \textit{mask\_csgrprnf}, \textit{mask\_csgrpemp}. 
     156\end{description} 
     157 
     158\begin{figure}[!tbp] 
     159  \centering 
     160  \includegraphics[width=0.66\textwidth]{MISC_closea_mask_example} 
     161  \caption[Mask fields for the \protect\mdl{closea} module]{ 
     162    Example of mask fields for the \protect\mdl{closea} module. 
     163    \textit{Left}: a \textit{mask\_csrnf} field; 
     164    \textit{Right}: a \textit{mask\_csgrprnf} field. 
     165    In this example, if \protect\np{ln_closea}{ln\_closea} is set to \forcode{.true.}, 
     166    the mean freshwater flux over each of the American Great Lakes will be set to zero, 
     167    and the total residual for all the lakes, if negative, will be put into 
     168    the St Laurence Seaway in the area shown.} 
     169  \label{fig:MISC_closea_mask_example} 
     170\end{figure} 
     171 
     172Closed sea not defined (because too small, issue in the bathymetry definition ...) are defined in \textit{mask\_csundef}. 
     173These points can be masked using the namelist option \np{ln_mask_csundef}{ln\_mask\_csundef}\forcode{= .true.} or used to correct the bathymetry input file.\\ 
     174 
     175The masks needed for the closed sea can be created using the DOMAINcfg tool in the utils/tools/DOMAINcfg directory. 
     176See \autoref{sec:clocfg} for details on the usage of definition of the closed sea masks. 
    187177 
    188178%% ================================================================================================= 
  • NEMO/trunk/doc/namelists/namberg

    r11703 r14303  
    3333   rn_speed_limit          = 0.      ! CFL speed limit for a berg 
    3434 
     35   ln_M2016                = .false. ! use Merino et al. (2016) modification (use of 3d ocean data instead of only sea surface data) 
     36      ln_icb_grd           = .false. ! ground icb when icb bottom level hit oce bottom level (need ln_M2016 to be activated) 
     37 
    3538   cn_dir      = './'      !  root directory for the calving data location 
    3639   !___________!_________________________!___________________!___________!_____________!________!___________!__________________!__________!_______________! 
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