Annual Summary Help

Purpose
The Annual summary section of the VIEWS web site provides access to data products described in the VIEWS scope of work.  It also provides browsing capabilities of the IMPROVE aerosol database using graphical interfaces.

Use
Pages in the Annual Summary are made up of VIEWS and CONTROLS.  The views represent  spatial, temporal, or compositional dimensions of the data.  The controls allow the user to update the views with selected data.  Some views are interactive in that the user can mouse click on various regions to update data selections.  For example, all Map Views allow the user to select a new monitoring location by clicking on a monitoring site icon.  Other views are static in that they do not respond to mouse clicks.

Data Views:

Page Controls:

Year
Select from available years.

Parameter
Select from available parameters.  A note on parameters that denote species fractional contributions:  As an example, the parameter F_(NH4)2SO4 is the fractional contribution of calculated ammonium sulfate to reconstructed fine mass.  The parameter F_(NH4)2SO4_bext is the fractional contribution of calculated ammonium sulfate extinction to chemical extinction.  When these fractional parameters are presented as aggregations over more than one sampling day the fractional contribution is calculated on a daily basis prior to aggregating the data.  This calculation method is referred to as taking the 'mean of ratios'.  Calculations using the 'mean of ratios' methodology are recommended for presentation of aggregated fractional species contributions of IMPROVE data.

Data Aggregation
Data aggregation options include the average of the annual, quarterly, and best or worst 20% of sampled days in the year. The best and worst 20% days can be chosen by using chemical extinction (aerosol_bext) or the selected parameter as a sort variable.

Sort Parameter
The Sort Parameter radio button becomes active if Best 20% or Worst 20% data aggregations are selected. This allows the user to choose between aerosol extinction or the selected parameter as sort variable.  For example, if CM (Coarse Mass) is selected in the parameter box the user can populate the map view with CM concentrations on the highest 20% aerosol extinction days OR the highest 20% CM concentrations days.  The time line view will highlight the sampling days included in the respective aggregation.

Interpolation
Interpolation refers to the interpolation scheme used to create the contour map.  Options are Kriging (Krig) and inverse distance weighting (1/R2).  The kriged surfaces were created using a spherical semivariogram model with model parameter range of 7 radial degrees and nuget of 0.  The 1/R2 interpolation uses the inverse square of the distance between each observation and grid point to form the weighted mean of all observations at each grid point.  In both interpolation schemes observations are interpolated to 1/2 degree latitude by 1/4 degree longitude grids.

Tabular Data Summary
This control allows for selection between data statistics for the chosen data aggregation and method information.

Data Views:

The daily timeline plot includes a daily sample status bar.  Located at the top of the timeline, the status bar indicates whether a daily sample is valid, contains substituted values, or is missing some or all of the aerosol components required to calculate aerosol extinction.  Daily samples missing some or all of the aerosol extinction components do not participate in the best and worst 20% groupings.  Sampling days excluded from the groupings but with some valid components are readily discernable from the status bar.

Tabular Data Summary  (Interactive radio button selection of method information or aggregate data statistics)
This view shows calculation method information for the selected parameter.

Page Controls:

Map
Use the map control to select regions and to zoom and pan the map.  The map Selection Pointer (a red cross) indicates the point on the map of your last mouse click.  The Selection Pointer remains in the same position when you zoom in or out.  Click on the pan compass image to move the map in a desired direction.  Clicking further from the compass center moves the map a greater distance.

Select from Year
Select from available years.

Data Aggregation
Select from available data aggregations. 'Available Species' shows any available mass components on a given sampling day. This is useful to fill gaps in the timeline when some but not all component species are missing.

Parameter
Select from available parameters.  Available Species will show the sum of available Total Mass components.  A note on the percentage values adjacent to the pie chart values:  The percentages indicate the contribution of each 'slice' of the pie to the sum of all components in the pie.  When percentages are calculated in this way the calculation method is referred to as taking the 'ratio of means'.  Due to the nature of the IMPROVE dataset, percentages calculated using the 'ratio of means' will not necessarily agree with percentages calculated using the 'mean of ratios' method (see the parameter section of either the Trends or Spatial Patterns pages).  Calculations using the 'mean of ratios' methodology are recommended for presentation of aggregated fractional species contributions of IMPROVE data.

Tabular Data Summary
This control allows for selection between data statistics for the chosen parameter, parameter composite species, and method information.

Data Views:

Page Controls:

Parameter
Select from available parameters.  A note on parameters that denote species fractional contributions:  As an example, the parameter F_(NH4)2SO4 is the fractional contribution of calculated ammonium sulfate to reconstructed fine mass.  The parameter F_(NH4)2SO4_bext is the fractional contribution of calculated ammonium sulfate extinction to chemical extinction.  When these fractional parameters are presented as aggregations over more than one sampling day the fractional contribution is calculated on a daily basis prior to aggregating the data.  This calculation method is referred to as taking the 'mean of ratios'.  Calculations using the 'mean of ratios' methodology are recommended for presentation of aggregated fractional species contributions of IMPROVE data.

Data Aggregation
Select from available data aggregations.

Trend Type
Select either annual averages or 5-year rolling averages. 5-year means are not currently available.

Time Plot Mode
The Timeline has two modes, 'Single' and 'Multi'. In Single mode the timeline will display your most recent selection.  In Multi mode each additional selection adds another timeline to the display. Up to 6 timelines can be superimposed in 'Multi' mode.  Parameters must have the same units to be superimposed in 'Multi' mode. To remove multiple plots from the view, select 'Single' mode and your most recent selection is displayed.

Data Views:

Map View  (Interactive selection of monitoring locations and compass pan control)
The map view displays back trajectories from the Atmospheric Transport and Deposition (ATAD) model. Click on a site icon to view trajectories ending at that site for a given day.  The selected site is displayed with a red icon.  The map also shows a compass icon that responds to mouse clicks and allows panning of the map image. The four daily trajectories shown on each map correspond to different arrival times in which an air parcel following the displayed trajectory arrives at the monitoring site.  Red trajectories arrive at 0500 hrs. on the selected day, white at 1100 hrs., blue at 1700 hrs., and black at 2300 hrs.  Arrival times are standardized to standard Mountain Time.  Each plot symbol on a trajectory indicates an air parcel position three hours older than the next parcel along the trajectory line to the site. Complete trajectories go back 5-days.

Timeline View  (Interactive selection of individual sampling days)
This view shows IMPROVE parameter values for the selected year.  The best and worst 20% aerosol extinction days can be highlighted to help associate individual sampling days with air mass source regions for that day. Click on a daily value from the timeline to display that days' trajectory, or use the BACK and FWD buttons to move to the next or previous days' trajectory. Trajectories are available for all days in the calendar year.

Tabular Data Summary (Static)
This view shows calculation method information for the selected parameter.

Page Controls:

Year
Select from available years.

Timeline Highlight
Select best or worst 20% aerosol extinction days to highlight in timeline.

Timeline Parameter
Select from available parameters to display in timeline.

Map Controls
Button Show/Hide Compass: Either show or hide the navigation compass at the lower left corner of the map.  The compass responds to mouse clicks which can be used to pan the map in any direction.  Clicks further from the compass' center move the map greater distances.  The map extent is 120 to 60 degrees west longitude and 22 to 50 degrees north latitude.  Button Center Map: Restores the default position of the map.  Button View Map Legend: show region of the map with legend information.

Time Step
Use the BACK and FWD buttons to move to the previous or next days' trajectory