SGP/RUC/X1 - Subsetting RUC-40

Users who would like access to subsetted RUC-40 data products similar to those products 
currently available for RUC-20 can use NCO utilities to create subsets from the 
"sgpallruc40" data products.  Below is one method that can be used. This is also mentioned in the 
FAQ on the ARM RUC description page at: http://www.arm.gov/xds/static/ruc.stm
--------------------------------------------------------------

Question: How can I create subsetted RUC 40 data similar to the RUC 20 data currently 
available at the Archive?

Currently, the RUC 40 netCDF data available at the archive are the full area, hourly files 
(sgpallruc40isobX1.c1 and sgpallruc40hybrX1.c1). Using the netCDF Operator (NCO) 
utilities, it is easy to produce subsetted, daily files similar to the RUC 20 subsets available 
(sgpruc20hybrX1.c1 and sgpruc20isobX1.c1).

The NCO utilities can be found at http://nco.sourceforge.net/
Using the ncks (NCO "kitchen sink") command, you can subset the ruc data as follows:

ncks -d nx,, -d ny,,  

Note: xmin,xmax,ymin,ymax are index ranges.

For example to subset around the SGP site use the following index values
for latitudes 34.209 to 38.928 and longitudes -99.798 to -95.
xmin = 71
xmax = 82
ymin = 40
ymax = 53


ncks -d nx,71,82 -d ny,40,53 sgpallruc40isobX1.c1.20000314.130000.cdf 
sgpruc40isobX1.c1.subset.cdf

Here is a sample C-Shell script for subsetting the ruc40 and using the NCO command ncrcat 
to concatenate the hourly subsetted files into a ruc 40 subsetted daily file similar to 
the sgpruc20isobX1.c1 files.

#!/bin/csh
# This script subsets the RUC 40 isobaric files
# and then concatenates hourly files into 1 daily file
# usage: subset_ruc40.csh 
#   where yyyymmdd is the date of the files to subset
#   and concatenate. Ex. 20000314 (yyyy=2000,mm=03, dd=14)
# Example: subset_ruc40.csh 20000314
# xmin,xmax,ymin,ymax are indices for
# lat = 34.209, 38.928, lon = -99.798, -95
set xmin = 71
set xmax = 82
set ymin = 40
set ymax = 53
set date = $1
foreach file (sgpallruc40isob*$date*)
  ncks -d nx,${xmin},${xmax} -d ny,${ymin},${ymax} $file $file.sub
end
ncrcat -h sgpallruc40isob*$date*sub sgpruc40isobX1.c1.$date.000000.cdf
rm *.sub
exit

For more information on the NCO commands ncks and ncrcat see:
http://nco.sourceforge.net/nco.html#ncks-netCDF-Kitchen-Sink
http://nco.sourceforge.net/nco.html#ncrcat-netCDF-Record-Concatenator

Also other commands for subsetting and analysis of netCDF data can be found at 
http://www.arm.gov/data/tools.stm

• Earth Surface Height(heightsrf)
• water equivalent snow depth(snowdepth)
• Lifted Index(indexlifted)
• Sub-surface Runoff(runoffsubsrf)
• Pressure at Freezing Level(pressurefrz)
• Dew Point Temperature (2 m fixed height)(tempdewpt2m)
• Potential Temperature (2 m fixed height)(temppot2m)
• Relative Humidity (p grid)(rhp)
• Resolvable Scale Precipitation (Accumulated)(precipresolvedacc)
• Potential Temperature at Tropopause(temppottrop)
• Sub-grid Scale Precipitation (3 hr)(precipsubgrid3hr)
• Environmental Temperature (2 m fixed height)(temp2m)
• east longitude(longitude)
• Gust Wind Speed(windgustspeed)
• north latitude(latitude)
• Environmental Temperature (m grid)(tempm)
• Geopotential Height at Freezing Level(heightgpfrz)
• v-Component of Wind (p grid)(windvp)
• Categorical Ice Pellets(caticepellets)
• v-Component of Wind at Maximum Wind Level(windvwindmax)
• Relative Humidity at Freezing Level(rhfrz)
• Pressure at Maximum Wind Level(pressurewindmax)
• Pressure at Tropopause(pressuretrop)
• Surface Altitude(altitude)
• Geopotential Height (p grid)(heightgpp)
• MAPS Pressure at Mean Sea Level(pressuremsl)
• Vertical Velocity (m grid)(velocitywm)
• Pressure at Top Freezing Level(pressurefrztop)
• Time offset from base_time(base_time)
• Altimeter Setting(altimeter)
• u-Component of Wind at Tropopause(windutrop)
• Sub-grid Scale Precipitation (Accumulated)(precipsubgridacc)
• Soil Moisture Availability(moistsoilavail)
• Surface Runoff Accumulated(runoffsrfacc)
• Categorical Snow(catsnow)
• Convective Cloud Top Height(heightcldtopconv)
• Precipitable water vapr, from MWR (through lssonde)(pwv)
• Snow Accumulation over 3-hr(snowaccum)
• Convective Inhibition(cinhib)
• Relative Humidity (2 m fixed height)(rh2m)
• u-Component of Wind at Maximum Wind Level(winduwindmax)
• Convective available potential energy(cape)
• Maximum Equivalent Potential Temperature Pressure(pressuretempeqpotmax)
• Pressure Tendency (3-hr)(pressuretend)
• v-Component of Storm Motion(stormmotionv)
• Environmental Temperature (p grid)(tempp)
• Precipitation Rate at Surface(preciprate)
• Vertical visibility(visibility)
• Cloud Top Height(heightcldtop)
• u-Component of Storm Motion(stormmotionu)
• Equilibrium Level Height(heightequillevel)
• Planetary Boundary Height(heightpbl)
• Vertical Velocity (p grid)(velocitywp)
• Storm-Relative Helicity 0-3 km(stormrelhelicity)
• Water Equivalent Snow Depth(snowdepthwatereq)
• Best Lifted Index(indexliftedbest)
• v-Component of Wind at Tropopause(windvtrop)
• Earth Surface Pressure(pressuresrf)
• Equivalent Potential temperature(tempeqpot)
• Categorical Rain(catrain)
• u-Component of Wind (m grid)(windum)
• v-Component of Wind (10 m fixed height)(windv10m)
• Pressure Intervals (30-0,60-30,90-60,120-90,150-120,180-150) of the m grid(pressuremgrid)
• Pressures of the p grid(pressurepgrid)
• v-Component of Wind (m grid)(windvm)
• Time offset of tweaks from base_time(time_offset)
• u-Component of Wind (p grid)(windup)
• Relative Humidity at Top Freezing Level(rhfrztop)
• Relative Humidity (m grid)(rhm)
• Geopotential Height at Top Freezing Level(heightgpfrztop)
• u-Component of Wind (10 m fixed height)(windu10m)
• Categorical Freezing Rain(catfreezerain)
• Dew Point Depression (2 m fixed height)(tempdewptdep2m)
• forecast period(forecast_period)
• Resolvable Scale Precipitation (3 hr)(precipresolved3hr)
• Specific Humidity (2 m fixed height)(sh2m)
• Cloud Base Height(heightcldbase)

• Mixing Ratio of Snow (hybrid-b grid)(mxratiosnow)
• Plant Canopy Surface Water(watercanopy)
• Net Shortwave Irradiance at Surface(fluxswnetsrf)
• Turbulent Kinetic Energy (hybrid-b grid)(tketurb)
• Pressure at Tropopause(pressuretrop)
• Surface,Sub-surface Soil Temperature(tempsoilsrfsubsrf)
• Mixing Ratio of Rain Water (hybrid-b grid)(mxratiorain)
• Time offset from base_time(base_time)
• north latitude(latitude)
• atmospheric pressure at mean sea level and at tropopause (NGM250 predicted)(pressure)
• Precipitable water vapr, from MWR (through lssonde)(pwv)
• Precipitation Rate at Surface(preciprate)
• u-Component of Wind at Tropopause(windutrop)
• Relative humidity scaled, by total column amount from MWR(rh)
• Surface,Sub-surface Soil Volumetric Moisture(moistsoilvolumesrfsubsrf)
• Convective Inhibition(cinhib)
• Mixing Ratio of Graupel (hybrid-b grid)(mxratiograupel)
• Sub-surface Runoff(runoffsubsrf)
• Mixing Ratio of Cloud Water (hybrid-b grid)(mxratioliquid)
• Mixing Ratio of Ice Water (hybrid-b grid)(mxratioice)
• Potential Temperature at Tropopause(temppottrop)
• Net Longwave Irradiance at Surface(fluxlwnetsrf)
• Snow Accumulation over 3-hr(snowaccum)
• v-Component of Wind at Tropopause(windvtrop)
• Rate of Water Dropping from Canopy to Ground(dropwaterratesrf)
• v-Component of Wind (hybrid-b grid)(windv)
• forecast period(forecast_period)
• Sub-grid Scale Precipitation at Surface(precipsubgrid)
• MAPS Pressure at Mean Sea Level(pressuremsl)
• Snow Temperature at Snow or Top Soil Level(snowtemp)
• water equivalent snow depth(snowdepth)
• Virtual Potential Temperature (hybrid-b grid)(tempvirtpot)
• Surface,Sub-surface Soil Moisture Content(moistsoilcontentsrfsubsrf)
• Sensible Heat Flux at Surface(fluxsensiblesrf)
• Mixing Ratio of Water Vapor (hybrid-b grid)(mxratiovapor)
• u-Component of Wind (hybrid-b grid)(windu)
• east longitude(longitude)
• Latent Heat Flux at Surface(fluxlatentsrf)
• Time offset of tweaks from base_time(time_offset)
• Water Condensation Rate near Surface(condensewaterratesrf)
• Surface Altitude(altitude)
• Evapotranspiration Flux near Surface(fluxevaptranssrf)
• Pressure Vertical Velocity (hybrid-b grid)(velocityw)
• Number Concentration of Ice Particles (hybrid-b grid)(ndensice)
• Resolvable Scale Precipitation at Surface(precipresolved)
• Surface Runoff(runoffsrf)
• Evaporation of Canopy Water near Surface(evapcanopysrf)
• Geopotential Height (hybrid-b grid)(heightgp)
• Convective available potential energy(cape)
• Environmental Temperature (hybrid-b grid)(temp)
• Evaporation from Bare Soil at Surface(evapsoilsrf)
• Surface/Sub-surface Heights(heightss)