Datagrams show the time evolution of various atmospheric constituents at a chosen location. A typical datagram will use multiple panels to visualize the evolution of the selected constituent(s) at the surface and above the location at multiple levels of the atmosphere. Meteorological fields such as clouds, moisture and temperature are also typically displayed. Time is displayed on the x-axis and may range from 5 to 10 days or longer
Surface concentrations represent the amount of a given constituent at or near the surface. It is typically derived from the lowest model level. Please see the 'Total Column' fields to assess the total amount of a given constituent throughout the atmosphere.
Total column fields represent the sum total of a given constituent throughout the atmosphere. It is derived by summing over all model layers from the surface to the top of the atmosphere (this is known as the 'column' at a given location). Use these fields to assess the total atmospheric content.