McIDAS User's Guide
Version 2018.2

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ISENT

Calculates theta surface levels for upper air data.


Format

ISENT sfile dfile day time btha etha inctha [keyword]


Parameters

sfile

MD file number of the mandatory level data (default=last digit of the current Julian day plus 10)

dfile

destination MD file; must not exist before running ISENT (no default)

day

year and day of the upper air data, YYDDD (default=current)

time

time of the upper air data observation, HHMM (default=0 UTC if the current time is less than 13:30 UTC, else 12 UTC)

btha

beginning theta value (default=280 K)

etha

ending theta value (default=350 K)

inctha

increment of the theta value (default=10 K)


Keyword

SIG=

MD file number of the significant level data (default=depends on sfile; see the Remarks)


Remarks

The ISEN schema must be registered on your workstation before you can use this command. See commands LSCHE and SCHE for more information. Also see Registering MD File Schemas.

A maximum of 18 theta levels can be calculated. Theta levels contain pressure, mixing ratio, u- and v-components, delta pressure, Montgomery stream function, and the theta value.

The sfile parameter and the SIG keyword specify the mandatory and significant level MD file numbers respectively. If sfile is in the default range of 11 to 20, the default for SIG is the value of sfile plus ten. If sfile is outside the range of 11 to 20, the default for SIG is the value of sfile plus one. For example, if sfile is 14, the default for SIG is 24; if sfile is 2500, the default for SIG is 2501.

To view data from the created MD file, use command MDX with a sort condition like the following: SORT=TIME 12 THA 300. This sort condition is for data at 12 UTC; the isentropic surface is 300 K. See command MDX for more information.


Examples

ISENT 14 150

This entry calculates the theta surface levels for all data in MD file 14 and stores the results in MD file 150.

ISENT X 1000 X 0 290 340

This entry calculates the theta surface levels between 290 and 340 for 0 UTC on the current day, and stores this information in MD file 1000.

 


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