Details and instructions on the monthly mean mapping page

Year entry box | Variables | Type of Plot (Mean, Long Term Mean and Anomaly)
Plotting Regions | Lagged Maps | Contour interval option | Page Creation | Feedback

Page will plot maps or vertical cross sections of selected pressure level variables. Select desired options and hit "create plot". Most options have a default setting so a selection is not required. Default for year is 2005. You can select the year/month to composite, the season, the type of statistic plotted (mean, anomaly, climatology), variable, level, map color, map area and contour interval/range. If you have problems, please email with ALL the options you chose. You will get a plot as well as the data used to create the final plot (in netCDF), a post script image and information on the dataset.

  • Dataset
    Various are provided. Differences are calculated by interpolating the lower spatial resolution values to higher, if the datasets aren't at the same resolution. Differences for vertical cross sections are calculated using this set of levels that is common to all the reanalyses we are using: 1000., 850.,700.,600.,500.,400.,300.,250.,200.,150.,100. Data is interpolated spatial as for maps. Currently the lower resolution of the CFSR is plotted (2.5x2.5). For the MERRA, we are using the lower as well (1.5). MERRA is not defined for values below the surface.
  • Variable
    Monthly data is available for each of the reanalyses for the time period of the reanalysis. variables.
  • Enter Year
  • Enter an integer year. If year is not in your dataset, you will get default year of 2005.
  • Variable Statistic
    Plots are the values from the model.
    The long term mean of the variable for a specified month is plotted. We use 1981-2010 where possible (1981-2008 20CR data).
    Plots are of mean-climatology for the variable. The climatology is monthly and each dataset has its own climatology.
  • Lags
    Selecting a nonzero value for this will allow you to do a lagged plot. A plot is made N months before the date you selected (-N) or after the date you selected (N). If lagging results in a date that is not in the range of the dataset, you will get an error or a default plot.
  • Map Type
    A lat/lon plot. Enter longitudes as for east to west. There are some custom regions provided:
    Latitude by Height
    A vertical cross section. Plot is averaged over longitudes supplied (east to west). Averages are only available for at most 360 degrees. For a plot at one longitude, enter the same value for eastern and western longitude bounds. Page will use nearest latitudes and longitudes to those selected.
    Longitude by Height
    A vertical cross section. Plot is averaged over latitudes supplied (south to north). For a plot at one latitude, enter the same value for southern and northern latitude bounds. Use decimal form of degrees. Page will use nearest latitudes and longitudes to those selected.
  • CUSTOM projection (maps)
    Currently, cylindrical or polar stereographic are provided.
  • Color and Shading
    You can select either color or black and white for the shading/contours. Contour types are simple contour lines, shade fill or both.
  • To increase/decrease plot size.
    you can increase or decrease the plot size by inputting a percentage between 1 and 200. The default is 100%. Values outside those ranges are ignored.
  • Plot contour labels
    Select this to draw contour labels on the contours.
  • To reverse color-bar
    Select this and colors will go from blue--> red to red--> blue. The contours themselves are unchanged.
  • Override default contour interval?
    A desired contour interval and range can be input instead of the default being used. This enables plots to be compared or generating images that can be animated. The interval (small to large) AND the range must be input. There is a limit of 150 contour levels with this method.
  • Output type?
    For maps, a user can choose "google earth". For this, a global map is created and put into kmz/kml format. In addition, for users with google earth browser installed, the map can be viewed in the google map application.
  • How this page was created
    The main interface for this page is an html form. The data that are input into this form are processed by a Perl script. The script reads the inputs, tests for bad inputs and then NCL is run to read, analyze and plot the data. NetCDF and postscript are also produced. For Google Earth, kmz and kml files are also created. The netCDF file, image and other files are kept in a directory in which the files are periodically deleted.
  • Feedback
    Please let me know if find the page useful. Likewise, let me know if you think any instructions are unclear, if you think there are bugs or if you have any suggestions for improvements of any type. I would particularly like to know if you use these pages for teaching purposes and if so, how. I can be reached by email at or by phone at (303) 497-6263.