***HAWAII EXPERIMENT TRAJECTORY README FILE***

Alex Pszenny and Gary Kleiman, MIT.

Back trajectories were calculated using the HYSPLIT-4 modeling system (NOAA Air Resources Laboratory, Silver Spring, MD, web address: http://www.arl.noaa.gov/ready/hysplit4.html).

Six-hourly archived FNL data were used as input. The FNL archive data come from NCEP's Global Data Assimilation System. The final run from a series of operational model runs is archived as the GDAS/FNL data.

Trajectories were run at 6-hour intervals during the 6 intensive sampling periods using a top model height of 12km. Individual back trajectories were calculated for 5 altitudes from 300 m to 9 km above 21.35N, 157.7W. Intermediate altitudes were selected based on inspection of temperature and wind profiles (provided by Steve Howell) to represent what appeared to be different layers in the vertical column.

Trajectory output file format (see example excerpt below)

     Record #1
     I6 - Number of meteorological grids used in calculation

     Loop Records #2 == > number of grids
     A8 - Meteorological Model identification
     5I6 - Data file starting Year, Month, Day, Hour, Forecast Hour

     Record #3
     I6 - number of different trajectories in file
     A8 - direction of trajectory calculation (FORWARD/BACKWARD)
     A8 - vertical motion calculation method (OMEGA, THETA,...)

     Loop Record #4 ==> number of different trajectories in file
     4I6 - starting year, month, day, hour
     2F8.3 - starting latitude, longitude
     F8.3 - starting level above ground (meters)

     Record #5
     I6 - number of diagnostic output variables
     nA8 - label identification of each variable (PRESSURE,THETA,...)

     Loop Record #6 ==> through end of all endpoints
     I6 - trajectory number
     I6 - meteorological grid number
     5I6 - time of point: year month day hour minute
     I6 - forecast hour at point
     F8.1 - age of the trajectory in hours
     2F8.3 - position latitude and longitude
     F8.1 - position height in meters above ground
     nF8.1 - n diagnostic output variables 

1
FNL 99 9 1 0 0
5BACKWARDOMEGA
99 9 4 0 21.350 -157.700 300
99 9 4 0 21.350 -157.700 1500
99 9 4 0 21.350 -157.700 2500
99 9 4 0 21.350 -157.700 5000
99 9 4 0 21.350 -157.700 9000
3PRESSURE HMIXING VMIXING
1 1 99 9 3 23 0 0 -1 21.442 -157.432  287.7 982.6 1.6 16.3
2 1 99 9 3 23 0 0 -1 21.455 -157.437 1460.6 857.6 3.2  0
3 1 99 9 3 23 0 0 -1 21.445 -157.453 2489.7 758   0.6  0
4 1 99 9 3 23 0 0 -1 21.593 -157.56  5036.8 553.7 3.6  0
5 1 99 9 3 23 0 0 -1 21.748 -157.775 9070.7 323.3 6.7  0
1 1 99 9 3 22 0 0 -2 21.532 -157.154  277.9 983.3 1   16.6
2 1 99 9 3 22 0 0 -2 21.558 -157.176 1427.9 860.5 1.2  0
3 1 99 9 3 22 0 0 -2 21.538 -157.203 2478.9 758.7 1.3  0
4 1 99 9 3 22 0 0 -2 21.835 -157.399 5078.6 550.7 3.4  0
5 1 99 9 3 22 0 0 -2 22.174 -157.813 9130.4 320   6.9  0

*****IMPORTANT:*****

Use of the HYSPLIT4 results in a publication REQUIRES the following citation:

"HYSPLIT4 (HYbrid Single-Particle Lagrangian Integrated Trajectory) Model, 1997. Web address: http://www.arl.noaa.gov/ready/hysplit4.html, NOAA Air Resources Laboratory, Silver Spring, MD."

For questions about these trajectory runs contact:

Alex Pszenny
Center for Global Change Science, Rm. 24-409
Massachusetts Institute of Technology
Cambridge, MA 02139-4307
USA
Tel: (+1-617) 258-7772
Fax: (+1-617) 253-9886
Email: pszenny@mit.edu