| 1 | 
\subsection{KPP: Nonlocal K-Profile Parameterization for  | 
| 2 | 
Vertical Mixing} | 
| 3 | 
 | 
| 4 | 
\label{sec:pkg:kpp} | 
| 5 | 
\begin{rawhtml} | 
| 6 | 
<!-- CMIREDIR:package_kpp: --> | 
| 7 | 
\end{rawhtml} | 
| 8 | 
 | 
| 9 | 
Authors: Dimitris Menemenlis and Patrick Heimbach | 
| 10 | 
 | 
| 11 | 
\subsubsection{Introduction | 
| 12 | 
\label{sec:pkg:kpp:intro}} | 
| 13 | 
 | 
| 14 | 
The nonlocal K-Profile Parameterization (KPP) scheme | 
| 15 | 
of \cite{lar-eta:94} unifies the treatment of a variety of  | 
| 16 | 
unresolved processes involved in vertical mixing.  | 
| 17 | 
To consider it as one mixing scheme is, in the view of the authors, | 
| 18 | 
somewhat misleading since it consists of several entities | 
| 19 | 
to deal with distinct mixing processes in the ocean's surface  | 
| 20 | 
boundary layer, and the interior: | 
| 21 | 
% | 
| 22 | 
\begin{enumerate} | 
| 23 | 
% | 
| 24 | 
\item | 
| 25 | 
mixing in the interior is goverened by | 
| 26 | 
shear instability (modeled as function of the local gradient | 
| 27 | 
Richardson number), internal wave activity (assumed constant), | 
| 28 | 
and double-diffusion (not implemented here). | 
| 29 | 
% | 
| 30 | 
\item | 
| 31 | 
a boundary layer depth $h$ or \texttt{hbl} is determined | 
| 32 | 
at each grid point, based on a critical value of turbulent | 
| 33 | 
processes parameterized by a bulk Richardson number; | 
| 34 | 
% | 
| 35 | 
\item | 
| 36 | 
mixing is strongly enhanced in the boundary layer under the | 
| 37 | 
stabilizing or destabilizing influence of surface forcing  | 
| 38 | 
(buoyancy and momentum) enabling boundary layer properties | 
| 39 | 
to penetrate well into the thermocline;  | 
| 40 | 
mixing is represented through a polynomial profile whose  | 
| 41 | 
coefficients are determined subject to several contraints; | 
| 42 | 
% | 
| 43 | 
\item | 
| 44 | 
the boundary-layer profile is made to agree with similarity | 
| 45 | 
theory of turbulence and is matched, in the asymptotic sense | 
| 46 | 
(function and derivative agree at the boundary), | 
| 47 | 
to the interior thus fixing the polynomial coefficients;  | 
| 48 | 
matching allows for some fraction of the boundary layer mixing | 
| 49 | 
to affect the interior, and vice versa; | 
| 50 | 
% | 
| 51 | 
\item | 
| 52 | 
a ``non-local'' term $\hat{\gamma}$ or \texttt{ghat} | 
| 53 | 
which is independent of the vertical property gradient further  | 
| 54 | 
enhances mixing where the water column is unstable | 
| 55 | 
% | 
| 56 | 
\end{enumerate} | 
| 57 | 
% | 
| 58 | 
The scheme has been extensively compared to observations | 
| 59 | 
(see e.g. \cite{lar-eta:97}) and is now coomon in many | 
| 60 | 
ocean models. | 
| 61 | 
 | 
| 62 | 
The following sections will describe the KPP package | 
| 63 | 
configuration and compiling (\ref{sec:pkg:kpp:comp}), | 
| 64 | 
the settings and choices of runtime parameters | 
| 65 | 
(\ref{sec:pkg:kpp:runtime}), | 
| 66 | 
more detailed description of equations to which these | 
| 67 | 
parameters relate (\ref{sec:pkg:kpp:equations}), | 
| 68 | 
and key subroutines where they are used (\ref{sec:pkg:kpp:subroutines}), | 
| 69 | 
and diagnostics output of KPP-derived diffusivities, viscosities | 
| 70 | 
and boundary-layer/mixed-layer depths. | 
| 71 | 
 | 
| 72 | 
%---------------------------------------------------------------------- | 
| 73 | 
 | 
| 74 | 
\subsubsection{KPP configuration and compiling | 
| 75 | 
\label{sec:pkg:kpp:comp}} | 
| 76 | 
 | 
| 77 | 
As with all MITgcm packages, KPP can be turned on or off at compile time | 
| 78 | 
% | 
| 79 | 
\begin{itemize} | 
| 80 | 
% | 
| 81 | 
\item | 
| 82 | 
using the \texttt{packages.conf} file by adding \texttt{kpp} to it, | 
| 83 | 
% | 
| 84 | 
\item | 
| 85 | 
or using \texttt{genmake2} adding | 
| 86 | 
\texttt{-enable=kpp} or \texttt{-disable=kpp} switches | 
| 87 | 
% | 
| 88 | 
\end{itemize} | 
| 89 | 
(see Section \ref{sect:buildingCode}). | 
| 90 | 
 | 
| 91 | 
Parts of the KPP code can be enabled or disabled at compile time | 
| 92 | 
via CPP preprocessor flags. These options are set in | 
| 93 | 
\texttt{KPP\_OPTIONS.h}. Table \ref{tab:pkg:kpp:cpp} summarizes them. | 
| 94 | 
 | 
| 95 | 
\begin{table}[h!] | 
| 96 | 
\centering | 
| 97 | 
  \label{tab:pkg:kpp:cpp} | 
| 98 | 
  {\footnotesize | 
| 99 | 
    \begin{tabular}{|l|l|} | 
| 100 | 
      \hline  | 
| 101 | 
      \textbf{CPP option}  &  \textbf{Description}  \\ | 
| 102 | 
      \hline \hline | 
| 103 | 
        \texttt{\_KPP\_RL} &  | 
| 104 | 
          ~ \\ | 
| 105 | 
        \texttt{FRUGAL\_KPP} &  | 
| 106 | 
          ~ \\ | 
| 107 | 
        \texttt{KPP\_SMOOTH\_SHSQ} &  | 
| 108 | 
          ~ \\ | 
| 109 | 
        \texttt{KPP\_SMOOTH\_DVSQ} &  | 
| 110 | 
          ~ \\ | 
| 111 | 
        \texttt{KPP\_SMOOTH\_DENS} &  | 
| 112 | 
          ~ \\ | 
| 113 | 
        \texttt{KPP\_SMOOTH\_VISC} &  | 
| 114 | 
          ~ \\ | 
| 115 | 
        \texttt{KPP\_SMOOTH\_DIFF} &  | 
| 116 | 
          ~ \\ | 
| 117 | 
        \texttt{KPP\_ESTIMATE\_UREF} &  | 
| 118 | 
          ~ \\ | 
| 119 | 
        \texttt{INCLUDE\_DIAGNOSTICS\_INTERFACE\_CODE} &  | 
| 120 | 
          ~ \\ | 
| 121 | 
        \texttt{KPP\_GHAT} &  | 
| 122 | 
          ~ \\ | 
| 123 | 
        \texttt{EXCLUDE\_KPP\_SHEAR\_MIX} &  | 
| 124 | 
          ~ \\ | 
| 125 | 
      \hline | 
| 126 | 
    \end{tabular} | 
| 127 | 
  } | 
| 128 | 
  \caption{~} | 
| 129 | 
\end{table} | 
| 130 | 
 | 
| 131 | 
 | 
| 132 | 
%---------------------------------------------------------------------- | 
| 133 | 
 | 
| 134 | 
\subsubsection{Run-time parameters | 
| 135 | 
\label{sec:pkg:kpp:runtime}} | 
| 136 | 
 | 
| 137 | 
Run-time parameters are set in files  | 
| 138 | 
\texttt{data.pkg} and \texttt{data.kpp} | 
| 139 | 
which are read in \texttt{kpp\_readparms.F}. | 
| 140 | 
Run-time parameters may be broken into 3 categories: | 
| 141 | 
(i) switching on/off the package at runtime, | 
| 142 | 
(ii) required MITgcm flags, | 
| 143 | 
(iii) package flags and parameters. | 
| 144 | 
 | 
| 145 | 
\paragraph{Enabling the package} | 
| 146 | 
~ \\ | 
| 147 | 
% | 
| 148 | 
The KPP package is switched on at runtime by setting | 
| 149 | 
\texttt{useKPP = .TRUE.} in \texttt{data.pkg}. | 
| 150 | 
 | 
| 151 | 
\paragraph{Required MITgcm flags} | 
| 152 | 
~ \\ | 
| 153 | 
% | 
| 154 | 
The following flags/parameters of the MITgcm dynamical | 
| 155 | 
kernel need to be set in conjunction with KPP: | 
| 156 | 
 | 
| 157 | 
\begin{tabular}{ll} | 
| 158 | 
\texttt{implicitViscosity = .TRUE.} & enable implicit vertical viscosity \\ | 
| 159 | 
\texttt{implicitDiffusion = .TRUE.} & enable implicit vertical diffusion \\ | 
| 160 | 
\end{tabular} | 
| 161 | 
 | 
| 162 | 
 | 
| 163 | 
\paragraph{Package flags and parameters} | 
| 164 | 
~ \\ | 
| 165 | 
% | 
| 166 | 
Table \ref{tab:pkg:kpp:runtime_flags} summarizes the | 
| 167 | 
runtime flags that are set in \texttt{data.pkg}, and | 
| 168 | 
their default values. | 
| 169 | 
 | 
| 170 | 
\begin{table}[h!] | 
| 171 | 
\centering | 
| 172 | 
  \label{tab:pkg:kpp:runtime_flags} | 
| 173 | 
  {\footnotesize | 
| 174 | 
    \begin{tabular}{|l|c|l|} | 
| 175 | 
      \hline  | 
| 176 | 
      \textbf{Flag/parameter} & \textbf{default} &  \textbf{Description}  \\ | 
| 177 | 
      \hline \hline | 
| 178 | 
         \multicolumn{3}{|c|}{\textit{I/O related parameters} } \\ | 
| 179 | 
         \hline | 
| 180 | 
        kpp\_freq & \texttt{deltaTClock} &  | 
| 181 | 
           Recomputation frequency for KPP fields \\ | 
| 182 | 
        kpp\_dumpFreq & \texttt{dumpFreq} &  | 
| 183 | 
           Dump frequency of KPP field snapshots \\ | 
| 184 | 
        kpp\_taveFreq & \texttt{taveFreq} &  | 
| 185 | 
           Averaging and dump frequency of KPP fields \\ | 
| 186 | 
        KPPmixingMaps & \texttt{.FALSE.} &  | 
| 187 | 
           include KPP diagnostic maps in STDOUT \\ | 
| 188 | 
        KPPwriteState & \texttt{.FALSE.} &  | 
| 189 | 
           write KPP state to file \\ | 
| 190 | 
        KPP\_ghatUseTotalDiffus & \texttt{.FALSE.} &  | 
| 191 | 
           if \texttt{.T.} compute non-local term using total vertical diffusivity \\ | 
| 192 | 
        ~ & ~ & | 
| 193 | 
           if \texttt{.F.} use KPP vertical diffusivity \\ | 
| 194 | 
      \hline | 
| 195 | 
      \multicolumn{3}{|c|}{\textit{Genral KPP parameters} } \\ | 
| 196 | 
      \hline | 
| 197 | 
        minKPPhbl & \texttt{delRc(1)} &  | 
| 198 | 
           Minimum boundary layer depth \\ | 
| 199 | 
        epsilon & 0.1 &  | 
| 200 | 
           nondimensional extent of the surface layer \\ | 
| 201 | 
        vonk & 0.4 &  | 
| 202 | 
           von Karman constant \\ | 
| 203 | 
        dB\_dz & 5.2E-5 1/s$^2$ &  | 
| 204 | 
           maximum dB/dz in mixed layer hMix \\ | 
| 205 | 
        concs & 98.96 & | 
| 206 | 
           ~ \\ | 
| 207 | 
        concv & 1.8 & | 
| 208 | 
           ~ \\ | 
| 209 | 
      \hline | 
| 210 | 
      \multicolumn{3}{|c|}{\textit{Boundary layer parameters (S/R \texttt{bldepth})} } \\ | 
| 211 | 
      \hline | 
| 212 | 
        Ricr & 0.3 &  | 
| 213 | 
           critical bulk Richardson number \\ | 
| 214 | 
        cekman & 0.7 &  | 
| 215 | 
           coefficient for Ekman depth \\ | 
| 216 | 
        cmonob & 1.0 &  | 
| 217 | 
           coefficient for Monin-Obukhov depth \\ | 
| 218 | 
        concv & 1.8 &  | 
| 219 | 
           ratio of interior to  entrainment depth buoyancy frequency \\ | 
| 220 | 
        hbf & 1.0 &  | 
| 221 | 
           fraction of depth to which absorbed solar radiation contributes \\ | 
| 222 | 
        ~ & ~ & | 
| 223 | 
           to surface buoyancy forcing \\ | 
| 224 | 
        Vtc & \texttt{~} &  | 
| 225 | 
           non-dim. coeff. for velocity scale of turbulant velocity shear \\ | 
| 226 | 
        ~ & ~ & | 
| 227 | 
           ( = function of concv,concs,epsilon,vonk,Ricr) \\ | 
| 228 | 
      \hline | 
| 229 | 
      \multicolumn{3}{|c|}{\textit{Boundary layer mixing parameters (S/R \texttt{blmix})} } \\ | 
| 230 | 
      \hline | 
| 231 | 
        cstar & 10. &  | 
| 232 | 
           proportionality coefficient for nonlocal transport \\ | 
| 233 | 
        cg & ~ &  | 
| 234 | 
           non-dimensional coefficient for counter-gradient term \\ | 
| 235 | 
        ~ & ~ & | 
| 236 | 
           ( = function of cstar,vonk,concs,epsilon) \\ | 
| 237 | 
      \hline | 
| 238 | 
      \multicolumn{3}{|c|}{\textit{Interior mixing parameters (S/R \texttt{Ri\_iwmix})} } \\ | 
| 239 | 
      \hline | 
| 240 | 
        Riinfty & 0.7 &  | 
| 241 | 
           gradient Richardson number limit for shear instability \\ | 
| 242 | 
        BVDQcon & -0.2E-4 1/s$^2$ &  | 
| 243 | 
           Brunt-V\"ai\"sal\"a squared \\ | 
| 244 | 
        difm0 & 0.005 m$^2$/s &  | 
| 245 | 
           viscosity max. due to shear instability \\ | 
| 246 | 
        difs0 & 0.005 m$^2$/s &  | 
| 247 | 
           tracer diffusivity max. due to shear instability \\ | 
| 248 | 
        dift0 & 0.005 m$^2$/s &  | 
| 249 | 
           heat diffusivity max. due to shear instability \\ | 
| 250 | 
        difmcon & 0.1 &  | 
| 251 | 
           viscosity due to convective instability \\ | 
| 252 | 
        difscon & 0.1 &  | 
| 253 | 
           tracer diffusivity due to convective instability \\ | 
| 254 | 
        diftcon & 0.1 &  | 
| 255 | 
           heat diffusivity due to convective instability \\ | 
| 256 | 
      \hline | 
| 257 | 
      \multicolumn{3}{|c|}{\textit{Double-diffusive mixing parameters (S/R \texttt{ddmix})} } \\ | 
| 258 | 
      \hline | 
| 259 | 
        Rrho0 & not used &  | 
| 260 | 
           limit for double diffusive density ratio \\ | 
| 261 | 
        dsfmax & not used &  | 
| 262 | 
           maximum diffusivity in case of salt fingering \\ | 
| 263 | 
         \hline | 
| 264 | 
      \hline | 
| 265 | 
    \end{tabular} | 
| 266 | 
  } | 
| 267 | 
  \caption{~} | 
| 268 | 
\end{table} | 
| 269 | 
 | 
| 270 | 
 | 
| 271 | 
 | 
| 272 | 
%---------------------------------------------------------------------- | 
| 273 | 
 | 
| 274 | 
\subsubsection{Equations | 
| 275 | 
\label{sec:pkg:kpp:equations}} | 
| 276 | 
 | 
| 277 | 
We restrict ourselves to writing out only the essential equations | 
| 278 | 
that relate to main processes and parameters mentioned above. | 
| 279 | 
We closely follow the notation of \cite{lar-eta:94}. | 
| 280 | 
 | 
| 281 | 
\paragraph{Mixing in the boundary layer} ~ \\ | 
| 282 | 
% | 
| 283 | 
~ | 
| 284 | 
 | 
| 285 | 
The vertical fluxes $\overline{wx}$ | 
| 286 | 
of momentum and tracer properties $X$ | 
| 287 | 
is composed of a gradient-flux term (proportional to | 
| 288 | 
the vertical property divergence $\partial_z X$), and | 
| 289 | 
a ``nonlocal'' term $\gamma_x$ that enhances the | 
| 290 | 
gradient-flux mixing coefficient $K_x$ | 
| 291 | 
% | 
| 292 | 
\begin{equation} | 
| 293 | 
\overline{wx}(d) \, = \, -K_x \left( | 
| 294 | 
\frac{\partial X}{\partial z} \, - \, \gamma_x \right) | 
| 295 | 
\end{equation} | 
| 296 | 
 | 
| 297 | 
\begin{itemize} | 
| 298 | 
% | 
| 299 | 
\item | 
| 300 | 
\textit{Boundary layer mixing profile} \\ | 
| 301 | 
% | 
| 302 | 
It is expressed as the product of the boundary layer depth $h$, | 
| 303 | 
a depth-dependent turbulent velocity scale $w_x(\sigma)$ and a | 
| 304 | 
non-dimensional shape function $G(\sigma)$ | 
| 305 | 
% | 
| 306 | 
\begin{equation} | 
| 307 | 
K_x(\sigma) \, = \, h \, w_x(\sigma) \, G(\sigma) | 
| 308 | 
\end{equation} | 
| 309 | 
% | 
| 310 | 
with dimensionless vertical coordinate $\sigma = d/h$. | 
| 311 | 
For details of $ w_x(\sigma)$ and $G(\sigma)$ we refer to | 
| 312 | 
\cite{lar-eta:94}. | 
| 313 | 
 | 
| 314 | 
% | 
| 315 | 
\item | 
| 316 | 
\textit{Nonlocal mixing term} \\ | 
| 317 | 
% | 
| 318 | 
The nonlocal transport term $\gamma$ is nonzero only for | 
| 319 | 
tracers in unstable (convective) forcing conditions. | 
| 320 | 
Thus, depending on the  stability parameter $\zeta = d/L$  | 
| 321 | 
(with depth $d$, Monin-Obukhov length scale $L$) | 
| 322 | 
it has the following form: | 
| 323 | 
% | 
| 324 | 
\begin{eqnarray} | 
| 325 | 
\begin{array}{cl} | 
| 326 | 
\gamma_x \, = \, 0 & \zeta \, \ge \, 0 \\ | 
| 327 | 
~ & ~ \\ | 
| 328 | 
\left. | 
| 329 | 
\begin{array}{c} | 
| 330 | 
\gamma_m \, = \, 0 \\ | 
| 331 | 
 ~ \\ | 
| 332 | 
\gamma_s \, = \, C_s  | 
| 333 | 
\frac{\overline{w s_0}}{w_s(\sigma) h} \\ | 
| 334 | 
 ~ \\ | 
| 335 | 
\gamma_{\theta} \, = \, C_s | 
| 336 | 
\frac{\overline{w \theta_0}+\overline{w \theta_R}}{w_s(\sigma) h} \\ | 
| 337 | 
\end{array} | 
| 338 | 
\right\}  | 
| 339 | 
& | 
| 340 | 
\zeta \, < \, 0 \\ | 
| 341 | 
\end{array} | 
| 342 | 
\end{eqnarray} | 
| 343 | 
 | 
| 344 | 
\end{itemize} | 
| 345 | 
 | 
| 346 | 
 | 
| 347 | 
\paragraph{Mixing in the interior} ~ \\ | 
| 348 | 
% | 
| 349 | 
~ | 
| 350 | 
 | 
| 351 | 
\paragraph{Implicit time integration} ~ \\ | 
| 352 | 
% | 
| 353 | 
~ | 
| 354 | 
 | 
| 355 | 
%---------------------------------------------------------------------- | 
| 356 | 
 | 
| 357 | 
\subsubsection{Key subroutines | 
| 358 | 
\label{sec:pkg:kpp:subroutines}} | 
| 359 | 
 | 
| 360 | 
\paragraph{kpp\_calc:} Top-level routine. \\ | 
| 361 | 
~ | 
| 362 | 
 | 
| 363 | 
\paragraph{kpp\_mix:} Intermediate-level routine \\ | 
| 364 | 
~ | 
| 365 | 
 | 
| 366 | 
\paragraph{ri\_iwmix:} ~ \\ | 
| 367 | 
% | 
| 368 | 
Compute interior viscosity and diffusivity coefficients due to | 
| 369 | 
% | 
| 370 | 
\begin{itemize} | 
| 371 | 
% | 
| 372 | 
\item | 
| 373 | 
shear instability (dependent on a local gradient Richardson number), | 
| 374 | 
% | 
| 375 | 
\item | 
| 376 | 
to background internal wave activity, and | 
| 377 | 
% | 
| 378 | 
\item | 
| 379 | 
to static instability (local Richardson number < 0). | 
| 380 | 
% | 
| 381 | 
\end{itemize} | 
| 382 | 
 | 
| 383 | 
 | 
| 384 | 
\paragraph{bldepth:} ~ \\ | 
| 385 | 
% | 
| 386 | 
The oceanic planetary boundary layer depth, \texttt{hbl}, is determined as | 
| 387 | 
the shallowest depth where the bulk Richardson number is | 
| 388 | 
equal to the critical value, \texttt{Ricr}. | 
| 389 | 
 | 
| 390 | 
Bulk Richardson numbers are evaluated by computing velocity and | 
| 391 | 
buoyancy differences between values at zgrid(kl) < 0 and surface | 
| 392 | 
reference values. | 
| 393 | 
In this configuration, the reference values are equal to the | 
| 394 | 
values in the surface layer. | 
| 395 | 
When using a very fine vertical grid, these values should be | 
| 396 | 
computed as the vertical average of velocity and buoyancy from | 
| 397 | 
the surface down to epsilon*zgrid(kl). | 
| 398 | 
 | 
| 399 | 
When the bulk Richardson number at k exceeds Ricr, hbl is | 
| 400 | 
linearly interpolated between grid levels zgrid(k) and zgrid(k-1). | 
| 401 | 
 | 
| 402 | 
The water column and the surface forcing are diagnosed for | 
| 403 | 
stable/ustable forcing conditions, and where hbl is relative | 
| 404 | 
to grid points (caseA), so that conditional branches can be | 
| 405 | 
avoided in later subroutines. | 
| 406 | 
 | 
| 407 | 
\paragraph{blmix:} ~ \\ | 
| 408 | 
% | 
| 409 | 
Compute boundary layer mixing coefficients. | 
| 410 | 
Mixing coefficients within boundary layer depend on surface | 
| 411 | 
forcing and the magnitude and gradient of interior mixing below | 
| 412 | 
the boundary layer ("matching"). | 
| 413 | 
% | 
| 414 | 
\begin{enumerate} | 
| 415 | 
% | 
| 416 | 
\item | 
| 417 | 
compute velocity scales at hbl | 
| 418 | 
% | 
| 419 | 
\item | 
| 420 | 
find the interior viscosities and derivatives at hbl | 
| 421 | 
% | 
| 422 | 
\item | 
| 423 | 
compute turbulent velocity scales on the interfaces | 
| 424 | 
% | 
| 425 | 
\item | 
| 426 | 
compute the dimensionless shape functions at the interfaces | 
| 427 | 
% | 
| 428 | 
\item | 
| 429 | 
compute boundary layer diffusivities at the interfaces | 
| 430 | 
% | 
| 431 | 
\item | 
| 432 | 
compute nonlocal transport term | 
| 433 | 
% | 
| 434 | 
\item | 
| 435 | 
find diffusivities at kbl-1 grid level | 
| 436 | 
% | 
| 437 | 
\end{enumerate} | 
| 438 | 
 | 
| 439 | 
\paragraph{kpp\_calc\_diff\_t/\_s, kpp\_calc\_visc:} ~  \\ | 
| 440 | 
% | 
| 441 | 
Add contribution to net diffusivity/viscosity from  | 
| 442 | 
KPP diffusivity/viscosity. | 
| 443 | 
 | 
| 444 | 
\paragraph{kpp\_transport\_t/\_s/\_ptr:} ~ \\ | 
| 445 | 
% | 
| 446 | 
Add non local KPP transport term (ghat) to diffusive | 
| 447 | 
temperature/salinity/passive tracer flux. | 
| 448 | 
The nonlocal transport term is nonzero only for scalars | 
| 449 | 
in unstable (convective) forcing conditions.  | 
| 450 | 
 | 
| 451 | 
\paragraph{Flow chart:} ~ \\ | 
| 452 | 
% | 
| 453 | 
{\footnotesize | 
| 454 | 
\begin{verbatim} | 
| 455 | 
 | 
| 456 | 
C     !CALLING SEQUENCE: | 
| 457 | 
c ... | 
| 458 | 
c  kpp_calc (TOP LEVEL ROUTINE) | 
| 459 | 
c  | | 
| 460 | 
c  |-- statekpp: o compute all EOS/density-related arrays | 
| 461 | 
c  |             o uses S/R FIND_ALPHA, FIND_BETA, FIND_RHO | 
| 462 | 
c  | | 
| 463 | 
c  |-- kppmix | 
| 464 | 
c  |   |--- ri_iwmix (compute interior mixing coefficients due to constant | 
| 465 | 
c  |   |              internal wave activity, static instability,  | 
| 466 | 
c  |   |              and local shear instability). | 
| 467 | 
c  |   | | 
| 468 | 
c  |   |--- bldepth (diagnose boundary layer depth) | 
| 469 | 
c  |   | | 
| 470 | 
c  |   |--- blmix (compute boundary layer diffusivities) | 
| 471 | 
c  |   | | 
| 472 | 
c  |   |--- enhance (enhance diffusivity at interface kbl - 1) | 
| 473 | 
c  |   o | 
| 474 | 
c  | | 
| 475 | 
c  |-- swfrac | 
| 476 | 
c  o | 
| 477 | 
 | 
| 478 | 
\end{verbatim} | 
| 479 | 
} | 
| 480 | 
 | 
| 481 | 
%---------------------------------------------------------------------- | 
| 482 | 
 | 
| 483 | 
\subsubsection{KPP diagnostics | 
| 484 | 
\label{sec:pkg:kpp:diagnostics}} | 
| 485 | 
 | 
| 486 | 
Diagnostics output is available via the diagnostics package | 
| 487 | 
(see Section \ref{sec:pkg:diagnostics}). | 
| 488 | 
Available output fields are summarized in  | 
| 489 | 
Table \ref{tab:pkg:kpp:diagnostics}. | 
| 490 | 
 | 
| 491 | 
\begin{table}[h!] | 
| 492 | 
\centering | 
| 493 | 
\label{tab:pkg:kpp:diagnostics} | 
| 494 | 
{\footnotesize | 
| 495 | 
\begin{verbatim} | 
| 496 | 
------------------------------------------------------ | 
| 497 | 
 <-Name->|Levs|grid|<--  Units   -->|<- Tile (max=80c) | 
| 498 | 
------------------------------------------------------ | 
| 499 | 
 KPPviscA| 23 |SM  |m^2/s           |KPP vertical eddy viscosity coefficient | 
| 500 | 
 KPPdiffS| 23 |SM  |m^2/s           |Vertical diffusion coefficient for salt & tracers | 
| 501 | 
 KPPdiffT| 23 |SM  |m^2/s           |Vertical diffusion coefficient for heat | 
| 502 | 
 KPPghat | 23 |SM  |s/m^2           |Nonlocal transport coefficient | 
| 503 | 
 KPPhbl  |  1 |SM  |m               |KPP boundary layer depth, bulk Ri criterion | 
| 504 | 
 KPPmld  |  1 |SM  |m               |Mixed layer depth, dT=.8degC density criterion | 
| 505 | 
 KPPfrac |  1 |SM  |                |Short-wave flux fraction penetrating mixing layer | 
| 506 | 
\end{verbatim} | 
| 507 | 
} | 
| 508 | 
\caption{~} | 
| 509 | 
\end{table} | 
| 510 | 
 | 
| 511 | 
%---------------------------------------------------------------------- | 
| 512 | 
 | 
| 513 | 
\subsubsection{Reference experiments} | 
| 514 | 
 | 
| 515 | 
lab\_sea: | 
| 516 | 
 | 
| 517 | 
natl\_box: | 
| 518 | 
 | 
| 519 | 
%---------------------------------------------------------------------- | 
| 520 | 
 | 
| 521 | 
\subsubsection{References} | 
| 522 | 
 |