--- Welcome to the official ADCIRCWiki site! The site is currently under construction, with limited information. ---
For general information, see the ADCIRC site, ADCIRC FAQ, or the ADCIRC Wikipedia page. For model documentation not yet available on the wiki, see the ADCIRC site. New content is being continuously added to the ADCIRCWiki, and material from the main ADCIRC site will be gradually transitioned over to the wiki.

Difference between revisions of "Fort.200 file format"

From ADCIRCWiki
Jump to: navigation, search
(File Structure)
(File Structure)
 
(One intermediate revision by the same user not shown)
Line 1: Line 1:
 
The basic file structure is shown below. Each line of input data is represented by a line containing the input variable name(s). Blank lines are only to enhance readability. Loops indicate multiple lines of input. Conditional input is indicated by an if clause.  
 
The basic file structure is shown below. Each line of input data is represented by a line containing the input variable name(s). Blank lines are only to enhance readability. Loops indicate multiple lines of input. Conditional input is indicated by an if clause.  
  
=NWS = 10 or 110=
+
=NWS = 10 or 110 or 10010 =
  
 
==File Structure==
 
==File Structure==
 
for k=1, [[LONB*LATB]]
 
for k=1, [[LONB*LATB]]
  
: [[PG(k)]], [[UG(k)]], [[VG(k)]] , ''optional:'' [[IG(k)]]  
+
: [[PG(k)]], [[UG(k)]], [[VG(k)]] , ''if NWS=10010:'' [[IG(k)]]  
  
 
end k loop
 
end k loop
 +
 +
'''Key:'''<br />
 +
[[PG(k)]]: surface pressure (Pa)<br />
 +
[[UG(k)]]: U10 wind speed (m/s)<br />
 +
[[VG(k)]]: V10 wind speed (m/s)<br />
 +
{{ADC version|version=55|relation=ge}} [[IG(k)]]: ice concentration (0-1 decimal fraction)
  
 
==Notes==
 
==Notes==

Latest revision as of 23:13, 29 June 2020

The basic file structure is shown below. Each line of input data is represented by a line containing the input variable name(s). Blank lines are only to enhance readability. Loops indicate multiple lines of input. Conditional input is indicated by an if clause.

NWS = 10 or 110 or 10010

File Structure

for k=1, LONB*LATB

PG(k), UG(k), VG(k) , if NWS=10010: IG(k)

end k loop

Key:
PG(k): surface pressure (Pa)
UG(k): U10 wind speed (m/s)
VG(k): V10 wind speed (m/s)

ADCIRC version: 55
IG(k): ice concentration (0-1 decimal fraction)

Notes

NWS = 10, US National Climatic Data Center (NCDC) Global Forecast System (GFS) model

Meteorological data is input to a T1534, Gaussian grid (NWLON*NWLAT is hardwired to 3072*1536 = 4,718,592) and interpolated in space onto the ADCIRC mesh. Data are ordered in these files the same way they are generated by the degribbing program.

The met data are contained in a sequence of files with names as follows: fort.200, fort.200+N, fort.200+2*N, fort.200+3*N,…., where N is the time interval (in hours) between successive meteorological data (e.g., at 6 hr intervals this would be fort.200, fort.206, fort.212, etc.). N is determined as N = WTIMINC/3600 where WTIMINC is the meteorological data time interval (in seconds) and is specified in the Model Parameter and Periodic Boundary Condition File. WTIMINC must be evenly divisible by 3600.

If the model is cold started, it is assumed that the winds are at rest at the beginning of the model run and no data file (fort.200) is read corresponding to TIME=STATIM. Rather, the first required data file (fort.200+N) corresponds to TIME=STATIM+WTIMINC. If the model is hot started, an initial file (fort.200) is required corresponding to TIME=HOT START TIME. In either case, additional sets of meteorological data must be provided every WTIMINC, in appropriately named files. Meteorological data is interpolated in time to the ADCIRC time step.

Wind velocity (@ 10 m above the water surface) must be input in units of m/s. Surface atmospheric pressure must be input in units of Pascals = Newtons/square meter.

The following relations are used to compute wind stress from the input wind velocity.

WIND_SPEED = magnitude of WIND_VEL

DRAG_COEFF = 0.001*(0.75+0.067*WIND_SPEED)

If (DRAG_COEFF.gt.0.003) DRAG_COEFF=0.003

WIND_STRESS = DRAG_COEFF*0.001293*WIND_VEL*WIND_SPEED

The following relationship is used in ADCIRC to convert to pressure in meters of water from pressure in Pascal:

PRESSURE{m H2O}=PRESSURE{Pascal}/(GRAVITY*DENSITY of H2O)

NWS = 11 or 111

File Structure

for k=1, 8

IYEAR, IMONTH, IDAY, IHOUR
for j=1, LONB*LATB
UE(j), VE(j), PE(j)
end j loop

end k loop

Notes

NWS = 11, 111 – National Weather Service Eta-29 file.

Meteorological data is input to the standard Eta-29 “E” grid, (non-cartesian grid, NWLON*NWLAT is hardwired to 181*271 = 49,051), and interpolated in space onto the ADCIRC grid. The ADCIRC grid must be in lon, lat coordinates.

The met data are contained in a sequence of files with names: fort.200, fort.201, fort.202, fort.203,…., Each file contains 8 data sets spaced 3 hrs apart in time (WTIMINC is the met. data time interval = 3600*3 = 10800 sec) for a total of 1 day of data per file. The first and last data sets in each file are assumed to correspond to 03:00 hrs and 24:00 hrs, respectively, on the day of the file. If the model is cold started, it is assumed that the winds are at rest at the beginning of the model run and no data file (fort.200) is read corresponding to TIME=STATIM. Rather, the initial data set in the first required data file (fort.201) corresponds to TIME=STATIM+WTIMINC. If the model is hot started, an initial file (fort.200) is required in which the last data set corresponds to TIME=HOT START TIME. In either case, 8 sets of met. data must be provided every WTIMINC in each file and appropriately named files must be provided for each day of the model run. Met data is interpolated in time to the ADCIRC time step.

The file type is binary: ACCESS=’sequential’, FORM=’unformatted’

Wind velocity (@ 10 m above the water surface) must be input in units of m/s oriented along the E grid coordinate directions. Surface atmospheric pressure must be input in units of millibars.

The following relations are used to compute wind stress from the input wind velocity.

WIND_SPEED = magnitude of WIND_VEL

DRAG_COEFF = 0.001*(0.75+0.067*WIND_SPEED)

If (DRAG_COEFF.gt.0.003) DRAG_COEFF=0.003

WIND_STRESS = DRAG_COEFF*0.001293*WIND_VEL*WIND_SPEED

The following relationship is used in ADCIRC to convert to pressure in meters of water from pressure in millibars.

PRESSURE{m H2O}=PRESSURE{millibars}/(100*GRAVITY*DENSITY of H2O)

The integer values IYEAR, IMONTH, IDAY, IHOUR are read in and ignored by ADCIRC.

General Note

Meteorological data must be provided for the entire model run, otherwise the run will crash.