Hysplit: To test Dry Deposition of Gases in HYSPLIT using a built-in example

1. Prepare the Basic Run Setup (if not already done)
• Open the main Setup Run window.
• Set Total run time (hrs): e.g., 12 or 25 (tutorial uses 25 h for noticeable deposition).
• Set Direction: Fwd (forward).
• Add meteorology: Click Add Meteorology Files and select your file (e.g., oct1618.BIN).
• Click Setup starting locations → define 1 source (e.g., lat 40.0, lon -90.0, height 50 m, emission rate suitable for test).

2. Set Pollutant & Deposition (Gas Dry Deposition)
• In main setup → click Pollutant, Concentration Grid, and Deposition setup.
• Under Pollutant: Num=1, select Specie 1.
• Under Deposition: Num=1, select Specie 1 → this opens the Deposition Definition window.
• In Deposition window:
• Particle or Gas: Gas.
• Dry Deposition: Yes.
• Wet Deposition: No.
• Preconfigure: Select I131g (built-in gaseous I-131 example; auto-loads realistic parameters like Vd ~0.006 m/s, molecular weight, Henry's law constants).
• Or manually: Set Vel(m/s) to 0.01 (1 cm/s, tutorial value for strong test).
• Leave other fields default/zero unless needed.
• Click green Save → close window.

3. Add Ground Deposition Level to Concentration Grid
• In the same Pollutant, Concentration Grid, and Deposition setup window:
• Under Grids: Num=1 → click radio for Grid 1 (or double-click/label) → opens Definition of Concentration Grid 1.
• In Grid Definition window:
• Num of vertical levels: Change from 1 to 2.
• Height of levels(M Agl): Change to 0 100 (space-separated; 0 first for deposition accumulation, 100 for air concentration layer).
• Optional: Update Center of Lat and Lon to match your source (e.g., 40.0 -90.0).
• Keep spacing/span reasonable (e.g., 0.05 deg, 30 deg span).
• Output grid file name: Keep cdump or change.
• Click green Save → close.

4. Run the Model
• Back in main Concentration Setup window → Save.
• Click Run Model (or equivalent button to execute HYSPLIT).
• Wait for completion → open the MESSAGE file in your working directory (text file named MESSAGE):
• Note the final total mass (near end, often in a NOTICE or summary line).
• Compare to initial emitted mass (early in file or from your emission setup: rate × duration).
• Look for vertical mass distribution tables (e.g., %Mass by height layer) — reduced low-level % indicates dry removal to ground.
• Compute % mass lost = (initial - final) / initial × 100. Tutorial expects ~10-14% for Vd=0.01 m/s over longer runs; shorter runs or lower Vd (like 0.006) show less.
• This confirms dry deposition occurred (mass removed from atmosphere).

5. Display the Results (Air Concentration + Deposition Footprint)
• Go to Display → Concentration Contours (opens your Concentration Display window).
• Key settings:
• Input File: cdump (or your output name).
• Select Pollutant: All or your species (e.g., I131 / II131).
• Vertical Display: Show Each Level.
• From Bottom Level: 0 (deposition/surface).
• Through Top Level: 100 (air layer).
• Deposition Multiplier: Select Total (shows cumulative/total deposited mass over entire run; critical for seeing the full footprint instead of incremental amounts).
• Keep numeric field 1.0 (unless scaling units).
• Concentration Multiplier: 1.0.
• Uncheck Exposure if checked.
• Contour drawing options: Dyn-Exp (dynamic exponential; best for plumes).
• Label Source Rings: On (shows distance rings around source; set Number=4, Dist=100 km, Center to your source lat/lon).
• Output File: e.g., dry_depo_plot (unique name).
• View On: Checked.


• Click green Execute Display.
• What you'll see (sequence through frames):
• Air concentration frames (at 100 m level): Reduced plume due to deposition loss.
• Final/cumulative frame (level 0 with Total): Colored deposition footprint on ground (accumulated mass deposited as plume passed).
• If blank: Confirm level 0 in grid, Vd > 0, re-run if needed.

11.2 Dry Deposition of Gases.

Matlab: Hysplit Toolkit

1. MATLAB Runs the Hysplit model
2. Mapping
3. Hysplit runs multiple datasets
4. Extract the layers from the ARL files
5. Construct Fishnet with Raster
6. RunHysplit.grids/isentropic
7. Bulit-in Function to Extract the Values from NAMS datasets
8. Conversion from ERA5 to ARL. 2nd
9. Conversion from ERA5-Land GRIB to TIF
10. ERA5-Isentropic

Hysplit: CONC.CFG

Breakdown of Parameters in CONC.CFG

The CONC.CFG file is a crucial configuration file that controls advanced settings for the HYSPLIT concentration (dispersion) model. It defines how calculations are performed and what output is generated, complementing the CONTROL file used in your MATLAB script.

Here's a breakdown of the CONC.CFG file structure and parameters:

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52

&SETUP tratio = 0.75, delt = 0.0, initd = 0, kpuff = 0, khmax = 9999, khinp = 0, numpar = 2500, maxpar = 10000, nbptyp = 1, qcycle = 0.0, efile = '', k10m = 1, kdef = 0, krand = 2, kzmix = 0, kbls = 1, kblt = 0, isot = -99, idsp = 1, wvert = .TRUE., plrise = 1, area = 0, vscale = 200.0, vscales = 5.0, vscaleu = 200.0, hscale = 10800.0, capemin = -1.0, tkemin = 0.001, uratio = 5.873300076, tvmix = 1.00, tkerd = 0.18, tkern = 0.18, kmix0 = 150, kmixd = 0, ninit = 1, ndump = 0, ncycl = 0, pinbc = 'PARINBC', pinpf = 'PARINIT', poutf = 'PARDUMP', messg = 'MESSAGE', vdist = 'VMSDIST', mgmin = 10, conage = 24, gemage = 48, kmsl = 0, kwet = 1, ichem = 0, cpack = 1, cmass = 0, kspl = 1, krnd = 6, frhmax = 3.00, splitf = 1.00, frhs = 1.00, frvs = 0.01, frts = 0.10, dxf = 1.00, dyf = 1.00, dzf = 0.01, /

Parameter Explanations

Core Simulation Parameters

• tratio = 0.75 - Time step ratio (stability factor). HYSPLIT adjusts its internal time step so a particle/puff doesn't travel more than 75% of a grid cell in one step. Potential values: 0.0 to 1.0 (typically 0.5–0.9). Affects how your pollutant (e.g., SO2) disperses in the atmosphere.
• delt = 0.0 - Fixed time step (minutes). 0.0 means HYSPLIT uses a variable time step controlled by tratio. Potential values: 0.0 (auto) or positive values (e.g., 1.0). Ensures efficient computation for your 48-hour simulation.
• initd = 0 - Particle/puff initialization method. 0 = 3D particle mode (pure Lagrangian, tracks individual particles), 1 = Gaussian horizontal puff, vertical particle, 2 = Top-hat horizontal puff, vertical particle, 3 = Gaussian puff (3D), 4 = Top-hat puff (3D). Suitable for detailed dispersion tracking in your SO2 simulation.
• kpuff = 0 - Horizontal puff growth option. 0 = Linear growth with time, 1 = Growth proportional to square root of time. Ignored since initd = 0. Not applicable in your current setup.
• khmax = 9999 - Maximum duration (hours) for a particle/puff. 9999 means "no limit". Potential values: Positive integers. Matches your 48-hour forward run (param.runTime).
• khinp = 0 - Input flag for puff splitting. 0 = No special input. Typically unused unless puff-splitting files are used. Not relevant unless customizing puff behavior.

Particle and Emission Parameters

• numpar = 2500 - Number of particles or puffs released per emission cycle. Potential values: Positive integers (e.g., 1000–10000). Controls how finely your SO2 emission (param.emissionRate = 1000 kg/hr) is resolved.
• maxpar = 10000 - Maximum total number of particles/puffs allowed. Potential values: Positive integers (e.g., 1000–100000). Ensures your simulation doesn’t crash due to too many particles.
• nbptyp = 1 - Number of bytes per particle in the output file (affects PARDUMP file size). Potential values: 1, 2, or 4. Affects the PARDUMP file if used (not in your script’s output).
• qcycle = 0.0 - Emission cycle time (hours). 0.0 = Continuous emission during emissionHours. Potential values: 0.0 or positive values (e.g., 1.0 for hourly pulses). Matches your 1-hour emission event (param.emissionHours = 1).
• efile = '' - Path to an emission input file for complex source configurations. Potential values: Empty string ('') or a file path. Not needed since your script specifies param.emissionRate.

Turbulence and Boundary Layer Parameters

• k10m = 1 - Use 10m wind data for turbulence calculations. Potential values: 0 (no), 1 (yes). Enhances accuracy near your 10m emission altitude (alt = 10).
• kdef = 0 - Horizontal turbulence deformation method. 0 = Based on velocity variances, 1 = Based on deformation field. Suitable for your general-purpose SO2 dispersion.
• krand = 2 - Random number generator for turbulence. Potential values: 1, 2, or 3. 2 is robust for your run.
• kzmix = 0 - Vertical mixing method. 0 = Use meteorology data, 1 = Scale by boundary layer depth. Matches your use of GDAS1 files in metPath.
• kbls = 1 - Boundary layer stability method. 0 = Use input meteorology, 1 = Compute from heat and momentum fluxes. Enhances realism for your SO2 dispersion.
• kblt = 0 - Boundary layer turbulence parameterization. 0 = Beljaars-Holtslag for stable, Kanthar-Clayson for unstable, 1 = Shortwave radiation-based. Good default for your simulation.
• isot = -99 - Isotropic turbulence flag. -99 = Disabled. Ignored in your run, safe to leave as is.
• idsp = 1 - Dispersion method. 0 = No dispersion (advection only), 1 = Dispersion with mixing. Essential for modeling SO2 spread in your script.
• wvert = .TRUE. - Enable vertical velocity in dispersion calculations. Potential values: .TRUE., .FALSE. Enhances vertical dispersion in your simulation.
• plrise = 1 - Plume rise calculation method. 0 = No plume rise, 1 = Briggs plume rise. Suitable if your SO2 source is a point source like a factory.
• area = 0 - Area source size (m²). 0 = Point source. Potential values: 0 or positive value. Matches your single-point emission (lat = 37.5, lon = -120.0, alt = 10).
• vscale, vscales, vscaleu = 200.0, 5.0, 200.0 - Turbulence velocity scales (m/s) for general, stable, and unstable conditions. Potential values: Positive values (e.g., 5.0–500.0). Affects how widely your SO2 disperses vertically.
• hscale = 10800.0 - Horizontal turbulence scale (seconds). Potential values: Positive values (e.g., 1000–10800). Influences horizontal spread of pollutants in your simulation.
• capemin = -1.0 - Minimum convective available potential energy (J/kg) for plume rise. -1.0 = Disabled. Simplifies your run, relying on plrise.
• tkemin = 0.001 - Minimum turbulent kinetic energy (m²/s²). Potential values: Small positive values (e.g., 0.001–0.1). Ensures turbulence in calm conditions.
• uratio = 5.873300076 - Ratio of wind speed to turbulence velocity. Potential values: Positive values (default ~5.87). Affects turbulence; default is fine.
• tvmix = 1.00 - Vertical mixing coefficient. Potential values: 0.0–1.0. Ensures realistic vertical dispersion.
• tkerd, tkern = 0.18, 0.18 - Daytime and nighttime turbulence ratios. Potential values: 0.1–0.5. Suitable for your run.
• kmix0 = 150 - Minimum mixing depth (m). Potential values: Positive integers (e.g., 50–500). Reasonable for near-surface emissions.

Initialization and Output Control

• kmixd = 0 - Mixing depth source. 0 = Use met data, 1 = Compute internally. Matches your reliance on GDAS1 files.
• ninit = 1 - Initialization of particles from PARINIT file. 0 = None, 1 = Read PARINIT if exists. Not used unless you specify pinpf.
• ndump = 0 - Interval (hours) for writing PARDUMP file. 0 = None. Potential values: Positive integers. Reduces output file size in your run.
• ncycl = 0 - Particle release cycle interval (hours). 0 = Continuous. Consistent with your 1-hour emission.
• pinbc = 'PARINBC' - Filename for boundary condition input. Potential values: File names or empty. Not used in your script.
• pinpf = 'PARINIT' - Filename for particle initialization. Potential values: File names or empty. Not used in your script.
• poutf = 'PARDUMP' - Filename for particle dump output. Potential values: File names or empty. Not used in your script.
• messg = 'MESSAGE' - Names the detailed log file generated by HYSPLIT. Potential values: File name or empty. Default is fine.
• vdist = 'VMSDIST' - Vertical distribution method. Potential values: String (default 'VMSDIST'). Controls vertical particle distribution; default is standard.
• mgmin = 10 - Minimum number of particles per grid cell for concentration output. Potential values: Positive integers. Ensures statistical reliability in your grid.
• conage = 24 - Maximum age (hours) for concentration calculations. Potential values: Positive integers. Fits your 48-hour run, limiting older contributions.
• gemage = 48 - Maximum age (hours) for particle transport. Potential values: Positive integers. Matches your runTime, ensuring particles don’t persist beyond your simulation.
• kmsl = 0 - Altitude input type. 0 = Meters above ground level (AGL), 1 = Meters above sea level (ASL). Matches your MATLAB input (alt = 10).

Deposition and Chemistry

• kwet = 1 - Enable wet deposition. 0 = Off, 1 = On. Ignored unless you modify HYSPLIT_writeControlConc.m to include deposition parameters.
• ichem = 0 - Chemistry module. 0 = None. Potential values: Other integers (see HYSPLIT docs). Suitable for your simple SO2 simulation.

Output File Parameters

• cpack = 1 - Concentration output packing. 0 = No packing, 1 = Packed binary output. Matches your cdump_test output.
• cmass = 0 - Concentration output type. 0 = Concentration (e.g., kg/m³), 1 = Mass loading (e.g., kg). Appropriate for analyzing SO2 concentrations.
• kspl = 1 - Particle/puff splitting interval (hours). 0 = No splitting. Enhances accuracy in your simulation.
• krnd = 6 - Random number seed control. Potential values: Positive integers. Ensures reproducible results.
• frhmax = 3.00 - Maximum horizontal puff growth factor. Potential values: Positive values (e.g., 1.0–5.0). Ignored since initd = 0.
• splitf, frhs, frvs, frts = 1.00, 1.00, 0.01, 0.10 - Splitting factors for puffs (horizontal, vertical, time). Potential values: Positive values. Ignored since initd = 0.
• dxf, dyf, dzf = 1.00, 1.00, 0.01 - Scaling factors for horizontal and vertical components of concentration output. Potential values: Positive values. Matches your grid settings (gridSpacing = 0.1).

Note: This configuration is set up for a standard concentration simulation with 2500 particles, continuous emission for 1 hour, and output in a packed binary cdump file. It uses 3D particle mode (initd = 0) for precise dispersion tracking, suitable for your SO2 simulation in MATLAB.

HYSPLIT CONC.CFG Configuration Guide | Understanding HYSPLIT Concentration Model Settings

Hysplit: TRAJ.CFG

Understanding the HYSPLIT TRAJ.CFG Configuration File

The TRAJ.CFG file is a crucial configuration file that controls advanced settings for the HYSPLIT trajectory model. It defines how calculations are performed and what output is generated.

Here's a breakdown of the TRAJ.CFG file structure and parameters:

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

&SETUP tratio = 0.75, delt = 0.0, mgmin = 10, khmax = 9999, kmixd = 0, kmsl = 0, kagl = 1, k10m = 1, nstr = 0, mhrs = 9999, nver = 0, tout = 60, tm_pres = 1, tm_tpot = 0, tm_tamb = 0, tm_rain = 0, tm_mixd = 0, tm_relh = 0, tm_sphu = 0, tm_mixr = 0, tm_dswf = 0, tm_terr = 0, tm_uwnd = 0, tm_vwnd = 0, dxf = 1.00, dyf = 1.00, dzf = 0.01, messg = 'MESSAGE', /

Parameter Explanations

Core Simulation Parameters

• tratio = 0.75 - Time step ratio (stability factor). HYSPLIT adjusts its internal time step so an air parcel doesn't travel more than 75% of a grid cell in one step.
• delt = 0.0 - Fixed time step (minutes). 0.0 means HYSPLIT uses variable time step controlled by tratio.
• mgmin = 10 - Minimum number of grid cells for met data. Sanity check to prevent errors with bad met files.
• khmax = 9999 - Maximum duration (hours) for a trajectory. 9999 means "no limit".

Vertical Motion & Starting Height

• kmixd = 0 - Boundary Layer option. 0 = Ignore mixing depth.
• kmsl = 0 - Input starting height reference. 0 = meters above ground level (AGL).
• kagl = 1 - Output height reference. 1 = meters above ground level (AGL).
• k10m = 1 - Use 10m meteorological data for surface-based trajectories.

Output Control

• nstr = 0 - Number of special starting locations. 0 means not used.
• mhrs = 9999 - Maximum duration for meteorological data. 9999 means "no limit".
• nver = 0 - Vertical motion output flag. 0 = Do not include vertical velocity.
• tout = 60 - Output frequency. 60 = Save trajectory position every 60 minutes.

Meteorological Output Variables (tm_ flags)

These control what additional meteorological data is written to the output file:

• tm_pres = 1 - Pressure (hPa or mb) - INCLUDED
• tm_tpot = 0 - Potential Temperature (K) - Excluded
• tm_tamb = 0 - Ambient Temperature (K) - Excluded
• tm_rain = 0 - Rainfall/Precipitation - Excluded
• tm_mixd = 0 - Mixing Depth (m) - Excluded
• tm_relh = 0 - Relative Humidity (%) - Excluded
• tm_sphu = 0 - Specific Humidity (g/kg) - Excluded
• tm_mixr = 0 - Water Mixing Ratio (g/kg) - Excluded
• tm_dswf = 0 - Downward ShortWave Radiation Flux (W/m²) - Excluded
• tm_terr = 0 - Terrain Height (m) - Excluded
• tm_uwnd = 0 - U-Wind Component (m/s) - Excluded
• tm_vwnd = 0 - V-Wind Component (m/s) - Excluded

Output File Scaling Factors

• dxf = 1.00, dyf = 1.00 - Scaling factors for horizontal components of trajectory dispersion.
• dzf = 0.01 - Scaling factor for vertical component of trajectory dispersion.

Log File Control

• messg = 'MESSAGE' - Names the detailed log file generated by HYSPLIT.

Note: This configuration is set up for a standard, single, backward trajectory with output in meters AGL, saved every 60 minutes, with pressure as the only additional meteorological variable.

HYSPLIT TRAJ.CFG Configuration Guide | Understanding HYSPLIT Model Settings

HYSPLIT Learning Resources

1. HYSPLIT后向轨迹制作. 2020-01-05
2. HYSPLIT聚类后向模拟及浓度扩散模拟. 2021-01-19
3. Internet-Based Hysplit Tool
4. NESDIS STAR, here.

Hysplit: Run a Sample Concentration Simulation

快捷方法，按照如图所示的步骤，单击‘Run Example’，就会得到运行的结果。

Quick method: follow the steps shown in the figure and click "Run Example" to obtain the results.

进一步，如果编辑运行需要的参数，请按照下面的步骤：

To proceed further and edit the parameters required for the run, please follow the steps below:

Step 1 配置参数 Configure Pollutant and Grid

在Concentration之下单击‘Setup Run’，在弹出的窗口再继续单击‘Pollutant, Deposition and Grids setup’，就可以在打开的新窗口对于Pollutant等进行调整，不过此为示例，已经调整到位了，无需再调整。

Under the ‘Concentration’ tab, click ‘Setup Run’. In the pop-up window, click ‘Pollutant, Deposition and Grids setup’ to open a new window where you can adjust the settings for the pollutant and related parameters. However, since this is just a sample, the settings have already been configured, and no further adjustments are needed.

Pollutant: Emission characteristics (e.g., emission rate, species like “TEST”).

Grid: Define the concentration grid (latitude-longitude intersections, resolution, and averaging period).

Deposition (optional): Parameters for deposition if needed.

全部单击‘Save’，保存这些配置。

Click ‘Save’ for each window to save the configurations.

Step 2 运行配置 Run the Simulation

在Concentration之下单击‘Run Model’，就开始运行，运行结束如下图。

Click ‘Run Model’ under the ‘Concentration’ tab to start the simulation. Once the run is complete, you will see the result as shown below.

Step 3 查看结果 View Output

按照下图的示意，单击‘Contours’，在新窗口有许多参数，可以尝试调整，也可以选择默认的配置，确定后执行‘Execute Display’。

As shown in the image below, click ‘Contours’. In the new window, you'll find many parameters available for adjustment. You can experiment with these settings or proceed with the default configuration. Once ready, click ‘Execute Display’ to generate the output.

最终弹出来的结果如下图。

The final output is shown in the image below.

Hysplit: Step-by-Step Guide to Use HYSPLIT GUI’s Built-in FTP Client

如下图所示，单击Archive。

As shown in the figure below, click ‘Archive’.

对于初学者来说，GDAS数据是一个不错的选择，覆盖全球，常用于Hysplit的模拟。其它方面请按照自己的需求而定，主要就是时间区间及下载位置，这里只是一个示例。设定好之后，就可以单击‘FTP Data File’开始下载。

For beginners, GDAS data is a good choice as it provides global coverage and is commonly used for HYSPLIT simulations. Other settings should be configured based on your specific needs, mainly the time range and download location—this is just an example. Once everything is set, you can click "FTP Data File" to start the download.

当出现‘FTP complete’，就表示下载完成了，此过程下载的文件名为‘gdas1.may24.w4’，位置在working文件夹。这就是一个简单的FTP下载过程。

When "FTP complete" appears, it means the download has finished. The downloaded file is named "gdas1.may24.w4" and is located in the ‘working’ folder. This is a simple FTP download process.

HRRR(High-Resolution Rapid Refresh)

High-Resolution: HRRR is a high-resolution weather model, meaning it operates on a fine spatial grid to capture detailed weather patterns. Specifically, it uses a 3-km horizontal resolution, allowing it to resolve smaller-scale phenomena like thunderstorms or local wind patterns that coarser models (e.g., GFS at 0.25-degree resolution) might miss.

Rapid Refresh: HRRR is updated frequently—every hour—with new data assimilation and forecasts. This rapid update cycle makes it ideal for short-term, real-time weather predictions, typically out to 18 hours (with some experimental runs extending to 48 hours).

Note

GDAS one-degree archive (Dec 2004 - present)

Currently Available Data

Browser[https://nomads.ncep.noaa.gov/pub/data/nccf/com/hysplit/prod/]

Forecast dataset available here.

FTP(e.g. FileZilla)[

Host: ftp.arl.noaa.gov

Username: anonymous

Password: (blank or your email)

Directory: /forecast

]

HYSPLIT Meteorological Data

Hysplit: To run the sample data

Hysplit安装成功后，其实就已经包含了示例数据，它位于安装位置的子目录working里面，请检查是否含有这三个文件oct1618.BIN（该文件是ARL格式的气象数据）/sample_traj/sample_conc。其中sample_traj定义了模拟过程的起始位置。

Once HYSPLIT is successfully installed, it already includes sample data located in the working subdirectory of the installation folder. Please check whether the following three files are present: oct1618.BIN (which is meteorological data in ARL format), sample_traj, and sample_conc. The sample_traj file defines the starting location for the simulation.

Step 1 双击“Run Hysplit” Double-click “Run HYSPLIT”

看到如下图所示的GUI，含有Meteorology/Trajectory/Concentration/Advanced.

You will see a GUI as shown below, which includes the tabs: Meteorology, Trajectory, Concentration, and Advanced.

Step 2 单击Trajectory Click on Trajectory

单击Trajectory后，选择Quick Start和Run Example。它会依据预定义的sample_traj开始运行oct1618.BIN。

After clicking 'Trajectory', select 'Quick Start' and then 'Run Example'. It will run based on the predefined `sample_traj` using the `oct1618.BIN` file.

'starting time'等在此软件使用的都是UTC时间，注意与希望的时间进行换算。

In this software, terms like “starting time” are all based on UTC. Please remember to convert accordingly to your desired local time.

几乎瞬间会得到一个运行结果，如下所示，黑色的星号就是计算的起始位置。

The result will appear almost instantly, as shown below. The black asterisk indicates the starting location of the calculation.

这就是一个非常简易的利用自带数据的操作过程。

This is a very simple operation process using the built-in data.

Step 3 查验气象数据 Verify Meteorological Data

在Trajactory之下找到Setup Run，弹出如下所示的配置窗口。

Under ‘Trajectory’, find and click ‘Setup Run’, and a configuration window like the one shown below will pop up.

在Selected Files，已经列出了oct1618.BIN文件，如果没有列出该文件，请通过“Add Meteorology Files”添加该文件。

In ‘Selected Files’, the file ‘oct1618.BIN’ should already be listed. If it is not, please click ‘Add Meteorology Files’ to add it manually.

单击“Setup starting locations”，如下图，你就会看到初涉的起始点是同一位置的不同高度，当然可以被修改为不同的位置或者高度。

Click ‘Setup starting locations’ (as shown below), and you will see that the initial starting points are set to the same location at different altitudes. Of course, these can be modified to different locations or altitudes as needed.

Step 4 运行此配置 Run the Simulation

单击Trajectory之下的Run Model，运行之后会得到如下结果。

Click ‘Run Model’ under the ‘Trajectory’ tab. After running, you will get the following results.

这个模拟的过程就是利用气象数据oct1618.BIN来得到的结果。

Click 'Run Model' under the 'Trajectory' tab. After execution, the results will be displayed as shown below.

Step 5 查看结果 View the output

Trajectory->Display->Trajectory，得到如下图所示，稍有调整，单击Execute Display。

Go to Trajectory → Display → Trajectory, as shown below. Make slight adjustments if needed, then click 'Execute Display'.

立即就得到一个展示结果，如下图。

The display result will appear immediately, as shown below. The trajplot program will run, generating trajplot.html in the working directory, as indicated by "Output will be in SVG".

同时，与结果一同输出的还有MESSAGE和tdump，他们也在working之下，可以作为运行过程相关参数的参考。

At the same time, the output also includes the MESSAGE and tdump files, which are located under the working directory. These files can serve as a reference for the parameters used during the run.

How to install HYSPLIT on Windows

在安装HYSPLIT之前，需要先安装Tcl/Tk和ImageMagick。

Before installing HYSPLIT, you need to install Tcl/Tk and ImageMagick first.

Tcl/Tk

打开Air Resources Laboratory - HYSPLIT Graphical Utilities，直接单击下图红框的链接，开始下载tcl.zip，下载后解压，并将整个文件夹放在你希望的地方，我一般放在C盘之下某个文件夹之下。

Open the "Air Resources Laboratory - HYSPLIT Graphical Utilities" page and click the link in the red box shown below to download tcl.zip. After downloading, extract the files and place the entire folder wherever you prefer — I usually place it in a subfolder under the C drive.

ImageMagick

继续在Air Resources Laboratory - HYSPLIT Graphical Utilities，单击下图红框的链接。

Still on the Air Resources Laboratory - HYSPLIT Graphical Utilities page, click the link in the red box shown below.

在新页面继续单击下方红框处的链接，选择最新版的软件。

On the new page, click the link in the red box again to select the latest version of the software.

在新打开的页面，找到Windows Binary Release之下，选择ImageMagick-XXXXXXX-dll.exe下载。

On the newly opened page, find the section titled Windows Binary Release, and select ImageMagick-XXXXXXX-dll.exe to download.

下载后，双击开始安装，安装在默认位置即可，当出现下图所示窗口时，务必选择两处，直至安装完毕。

After downloading, double-click the file to begin installation. Install it in the default location. When the window shown below appears, make sure to check both options before proceeding, and continue until the installation is complete.

HYSPLIT

参考Air Resources Laboratory - HYSPLIT Registration Instructions，该软件含有注册版本与非注册版本，注册版本仅多一个Forecast功能。一般，我们先安装非注册版本，注册版本根据需求来选择。打开HYSPLIT for Windows - Public (unregistered) Version Download，填写自己的邮箱即可开始下载。来到了下载列表，一般我选择最新版的.zip版本下载，解压后将其放在合适的位置即可使用。

According to the Air Resources Laboratory - HYSPLIT Registration Instructions, the software includes both a registered and an unregistered version. The registered version only provides one additional feature — Forecast.

Generally, we start by installing the unregistered version, and the registered version can be used as needed.

Go to the HYSPLIT for Windows - Public (unregistered) Version Download page, enter your email address to begin the download.

Once you reach the download list, it's recommended to download the latest .zip version. After downloading, extract the files and place them in a suitable location — the software is then ready to use.

Unzip the file and move the HYSPLIT folder and everything therein to the C: drive. The end result should have directories C:\HYSPLIT\exec, C:\HYSPLIT\working, and others. Then create the "Run Hysplit" shortcut on your desktop. To create the shortcut, open Windows Explorer and navigate to the C:\HYSPLIT\guicode directory. Right-click the hysplit.tcl file and then choose "Send To > Desktop (Create shortcut)." Rename the created shortcut to "Run Hysplit."

我们还需要另外一个路径，找到之前存放Tcl/Tk位置，找到其完整路径（XXXXXX\tcl\bin\wish86t.exe）并复制。

We also need another path: locate the folder where you previously saved Tcl/Tk, find the full path to wish86t.exe (e.g., `XXXXXX\tcl\bin\wish86t.exe`), and copy it.

回到刚刚在Desktop创建的"Run Hysplit"，右键找到Properties，在Target里面加入刚刚找到的路径，注意两个路径在一起，并有一个空格分开，最后单击OK完成。

Then, go back to the "Run Hysplit" shortcut you just created on your Desktop, right-click it and select Properties. In the Target field, add the path you just copied after the existing path. Make sure the two paths are separated by a space. Finally, click OK to save the changes.

双击"Run Hysplit"，就可以运行了。

Now, double-click "Run Hysplit" to launch the program.

Test the Installation with GUI

如图所示打开Contour Map，并在新窗口按照下图所示配置测试数据，最终单击“Run CONTOUR”。

As shown in the figure, open Contour Map, and in the new window, configure the test data as illustrated. Finally, click "Run CONTOUR".

如果返回如下图的结果，就表示安装成功了。

If you get a result like the one shown below, it means the installation was successful.

References

1. HYSPLIT - Wikipedia
2. Air Resources Laboratory - HYSPLIT - Hybrid Single Particle Lagrangian Integrated Trajectory model
3. HYSPLIT Basic Tutorial Contents ©
4. Hysplit User's Guide. April 2025.