Combined Aerosol Trajectory Tool, CATTStatus Report on Tools Development and Use

Project supported by the Inter-RPO Data Analysis Workgroup

Project Manager: Sirpil Kayin, MARAMA

Technical Project Officer: Rich Poirot, Vermont DEP

Project performed by CAPITA, Rudolf Husar, PI

July 2004

Trajectory Browser Kitty: Simple CATT CATT Transport Analyzer

Next Process

Next Process

Aerosol Data

Collection IMP. EPA

Aerosol Sensors

Integration VIEWS

Integrated AerData

AEROSOL

Weather Data

Assimilate NWS

Gridded Meteor.

Trajectory ARL

Traject.Data

TRANSPORT

TrajData Cube

Aggreg. Traject.

AerData Cube

CATT

Aggreg.Aerosol

CATT-In CAPITA

CATT-In CAPITA

New CATT Components:

Chemical filter

Accomplished through queries to chemical data sets.

The output a list of “qualified” dates for a specific location (s).

Trajectory aggregator

Receives the list of dates for a specific location

Performs the trajectory/restime aggregation

Yield transport pattern for specific receptor location and chemical filter conditions.

Trajectory Aggregator Tool Inputs: – Receptor location. Single location; multiple receptors; weighed multi-site

– Receptor times. Time range for each site

– Temporal filter/weight conditions. Date range; specific dates; weights for each date

– Trajectory input files. Pre-computed or on the fly calculated (e.g. HYSPLIT, ATAD etc)

– Trajectory aggregation metrics. Endpoint counts, residence time, incr. probability

TAT Output:– XMLGrid, GIS layers, ASCII point– Rendered contour images of transport metric

The CATT Family

• IMPROVE-ATAD Trajectory Browser Tool– This tool is used to find the airmass history for an IMPROVE site and time

• TrajAgg- Trajectory Aggregator (Grid)– Uses user-defined filter (locations and dates) to aggregate trajectories

• Kitty – Simple Combined Aerosol Trajectory Tool– Limited filtering and aggregation for IMPROVE-ATAD data

• CATT - Combined Aerosol Trajectory Tool (Threshold, Percentile, Ratio)

– Full featured chemical-transport exploration tool

IMPROVE-ATAD Trajectory Browser ToolThis tool is used to find the airmass history for

arbitrary location over the US and time

• Backtrajectory browser for IMPROVE sampling sites. Click on location and date.

• Fir a given sampling date, the backtrajectories for multiple receptor sites can be retrieved. The sites are specified in the URL, e.g.:

http://webapps.datafed.net/dvoy_services/datafed.aspx?view=atad

_map&loc_code=SALM+SAMA+SHEN+UPBU

TrajAgg- Trajectory Aggregator – User Defined Filter

This tool performs weighed trajectory aggregation using user-supplied filter

The filter can be submitted as a comma separated CSV table, shown here

The aggregator returns either trajectory or weighed contour plots

Kitty – Simple CATTCombined Aerosol Trajectory Tool

• All the VIEWS chemical parameters available for filtering

• Filter settable as Parameter-Operator-Threshold, e.g. SOILf >20 or SO4<5

CATT – Combined Aerosol Trajectory Aggregator

Differing TrajPoint weight combinations• These were all created using the CATT Aerosol Trajectory Aggregator

Uncertainty potential further away

The Role of Age Weighing: Example: Fine SOIL Transport Probability map to Shenandoah, July

Age weight factor = 1

Hi weighed restime near the receptor

Factor ~ square root of age

Weighed restime uniform along path

Recommended (why? Don’t know)

Factor ~ age

Hi weighed restime far from receptor

Transport Probability Metrics

• The transport metric is calculated from two residence time grids, one for all trajectories and another for trajectories on selected (filtered days). Both residence time grids are normalized by the sum of all resdence times in all grid cells:

pijf=rij/ rij pij

a=rij/ rij

• pijf, is the filtered and pij

a is the unfiltered residence time probability

that an air masses passes through a specific grid. There is a choice of transport probability metrics:

• The Incremental Residence Time Probability (IP) proposed by Poirot et al., 2001 is obtained by subtracting the chemically filtered grid from the unfiltered residence time grid, IRTP = pij

f - pija

• The other metric is the Potential Source Contribution Function (PSCF) proposed by Hopke et al., which is the ratio of the filtered and unfiltered residence time probabilities, PSCF = pij

f / pija

Incremental Transport Probability Analysis

• In the Incremental Probability Map, red areas represent high probability transport path• Blue zones represent the regions where a species are NOT coming from

Upper Buffalo

IMPROVE Site

Backtrajectories for top

10 percentile Soil, Jun, Jul, Aug

Backtrajectories for all days, Jun, Jul, Aug

Incremental Transport Probability, Jun, Jul, Aug

•First, the trajectories for top 10 percent SOILf are calculated•Next, the trajectories for all days are calculated•Thirdly, the

–Trajectory endpoints are gridded–Each grid is normalized to probability–The all-data grid is subtracted from filtered grid

Fine SOIL transport at decreasing concentration limit

Weight by 1 Calc high Percent days

Dust > 30 ug/m3

Dust > 1.8 ug/m3Dust > 3.7 ug/m3 Dust > 1.8 ug/m3

Dust > 15 ug/m3 Dust > 7.5 ug/m3

SO4 Multi-Site CATT

Incremental Probability Maps Upper 10 percentile, Big Bend, Jun, Jul Aug

• Incremental Transport Probabilities for Big Bend indicate southerly transport of species, except sulfate

• Conspicuously, in the summer, nitrate is also transported from the south

Incremental Probability Maps Upper 10 percentile, Brigantine, Jun, Jul Aug

Incremental Transport Probabilities for Brigantine indicate westerly transport of speciesSoil is preferentially transported from southwest; nitrate is transported from the northwest

Project Status:Extensions to the CATT Analysis Tool

1. Connectivity to VIEWS chemical datasets

• Done

2. Flexible import of pre-calculated back-trajectory data

• Done for ATAD, Nor done for HYSPLIT

3. Additional chemical filtering and trajectory aggregation algorithms

• Done for some, may add some filters

4. Spatial interpolation and rendering (contouring) of point data

• Done

5. CATT server hardware and software installation and maintenance

• Done