MTCLIM FILE DOCUMENTATION

8/1/89

Steven W. Running/Joseph C. Coughlan

University of Montana

This documentation package explains the execution and files needed for MTCLIM, a model for extrapolation of meteorological data in mountainous terrain from basic climatological principles. It is designed to complement Running et al., 1987, the original publication of this model. There will be a user's manual printed by the Forest Service sometime early in 1990.

Five files are included in this documentation:

MTCLIM.EXE This is the main program, compiled in Microsoft FORTRAN 4.1, ready to execute. Requires a 80x87 coprocessor.

MTCLIM.FOR This is the source code, in FORTRAN77. Written in MicroSoft FORTRAN (v 4.1), however it is compatible with most compilers. It is written to be readable and not efficient. See the source code for details on methods for optimizing the model for speed.

MISS84.DAT Initial input details, including site-specific information, name of climate file, etc. This file is self-explanatory and should be viewed before running the program. Please note that it is possible to use either metric or english units. Be consistent!

MISS84.MTC The base station climate file, containing yearday, max temp, min temp, dew point, and precipitation for each day. (Note that MISS84.DAT asks whether or not dew point is supplied - in this file it is not, so the flag is set to "N". If you wish to run MTCLIM with dew pt. information, you must create a new file with this column, then set flag to "N". If dew point is not supplied, it is assumed equal to night minimum temperature).

(See description of input format below)

The model itself is based on metric units. English units are converted inside the program before any computations are performed. Please make note of this if you are going to extract code from the model.

The met file can begin on day 1 and end day 365 or any period in between, i.e. day 150 to 283. It cannot operate from day 250 to day 100 (across day 365). Also, those of you 'down under' will need to correct the sun angle geometry for the southern hemisphere.

MISS84.CLM Climatic output file for the information provided in MISS84.DAT. For sample runs, you may change any of the switches in MISS84.DAT and create a new output file (specify new output name if you wish to keep both for comparison.) The format of the output file will vary depending on the switches you set in the .DAT file.

EXECUTION

To execute, just type MTCLIM at the Dos prompt. The output file is created with the name specified in MISS84.DAT. The model will echo a counter to the screen for each day. The program is math intensive and can take several minutes on a IBM AT class machine with an 80287.

If you are going to use MTCLIM output in conjunction with FOREST-BGC (Running and Coughlan, 1988)**, you must delete the header lines in the output file for compatibility with FOREST-BGC's read format. Currently we have added the .DAT file to the output file as a heading for distinguishing model runs (See FOREST-BGC for specific input requirements).

*Running, S.W., R.R. Nemani, and R.D. Hungerford, 1987 Extrapolation of synoptic meteorological data in mountainous terrain and its use for simulating forest evapotranspiration and photosynthesis. Canadian Journal of Forest Research 17: 472-83.

**Running, S.W. and J.C. Coughlan, 1988 A general model of forest ecosystem processes for regional applications. I. Hydrologic balance, canopy gas exchange and primary production. Ecological Modelling 42: 125-54.

MTCLIM Input Formats

Free format FORTRAN READs of each daily input record (no commas or fixed fields) for the following fields in the following order:

YEAR_DAY MAX_TEMP MIN_TEMP DEW_PT_TEMP PPT_1 PPT_2

Field data types:

INTEGER: YEAR_DAY (No decimal point allowed)

REAL: MAX_TEMP MIN_TEMP DEW_PT_TEMP PPT_1 PPT_2 (Decimal point allowed)

The following fields are optional and can be omitted from the input file provided that the .DAT file is configured for the new format. If an optional field is missing then the input file is missing that column, all other columns remain in the same order:

DEW_PT_TEMP PPT_2