# Data Extraction and Processing

<span>If your stakeholders would like to see and access the data they contributed, it may become pertinent that you download and share the data yourself. To do this, you will need to follow the steps outlined in the </span>[NCEI/DCDB data extraction](https://cms-kb.marine.usf.edu/books/crowdsourced-bathymetry-manual-working-version/page/nceidcdb-data-extraction "NCEI/DCDB data extraction")<span> section. Once raw data are obtained from the DCDB, they should be tide corrected using the CSB Processing Tool in Pydro Explorer, following the instructions in the </span>[Pydro tidal corrections](https://cms-kb.marine.usf.edu/books/crowdsourced-bathymetry-manual-working-version/page/pydro-tidal-corrections "Pydro tidal corrections")<span> section.</span>

# NCEI/DCDB data extraction

Perform the following steps to extract CSB data from the DCDB:

1. Go to the [IHO Data Centre for Digital Bathymetry Viewer](https://www.ncei.noaa.gov/maps/iho-data-centre-digital-bathymetry/).  
    ![DCDB_Landing_Map.jpg](https://cms-kb.marine.usf.edu/uploads/images/gallery/2026-08/dcdb-landing-map.jpg)
2. <span style="font-size: 12.0pt; line-height: 115%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: minor-bidi; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">Click the **IHO DCDB/NOAA NCEI** drop down menu, <u>uncheck</u> the ‘**Multibeam Dataset**’ layer(s), scroll down, and select the ‘**Crowdsourced Bathymetry**' layer (it is the last layer under the IHO DCDB/NOAA NCEI drop down menu).  
    </span>![DCDB_Viewer_Multibeam.png](https://cms-kb.marine.usf.edu/uploads/images/gallery/2026-08/dcdb-viewer-multibeam.png)
    
    ![DCDB_Viewer_CSB.png](https://cms-kb.marine.usf.edu/uploads/images/gallery/2026-08/scaled-1680-/dcdb-viewer-csb.png)
3. <span style="font-size: 12.0pt; line-height: 115%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: minor-bidi; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">As an alternative to steps 1 and 2, you can use [this link](https://www.ncei.noaa.gov/maps/iho-data-centre-digital-bathymetry/?csbVisible=true&multibeamAllVisible=false) (bookmark it) to navigate directly to the CSB data, instead of having to deselect the multibeam data.  
    </span>![DCDB_CSB_Direct_Landing.png](https://cms-kb.marine.usf.edu/uploads/images/gallery/2026-08/dcdb-csb-direct-landing.png)
4. <span style="font-size: 12.0pt; line-height: 115%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: minor-bidi; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">Zoom in on the area from which you want to extract data. You can also open the ‘**Filter Crowdsourced Bathymetry**’ carat to filter for a certain date range, Provider (Trusted Node), or Platform (vessel name), and zoom to filter results. This filter service automatically populates the filter as URL parameters, and you can copy and paste/save the filtered URLs for ease of reference.   
    </span>![DCDB_New_Filter_Options_2026.png](https://cms-kb.marine.usf.edu/uploads/images/gallery/2026-08/dcdb-new-filter-options-2026.png)
5. <span style="font-size: 12.0pt; line-height: 115%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: minor-bidi; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">When you are ready to extract data, click to expand the '**Filter by Geometry**' menu in the upper right corner and select the option you would like to use. You may select a bounding box by clicking and dragging on the map, or enter max/min coordinates.  
    </span>![image.png](https://cms-kb.marine.usf.edu/uploads/images/gallery/2026-09/scaled-1680-/image.png)
6. <span style="font-size: 12.0pt; line-height: 115%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: minor-bidi; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">Draw your bounding area of interest, select the ‘**Extract CSB Point Store Data**’ from the popup window. You will be prompted to enter an email address where the link to download files will be sent to. <u>Do not check the box for ‘Create a Grid in addition to the XYZ points file.</u>' Leave the default for the rest of the options. *NOTE: The Point Count value may remain at zero for large geographic extents or high density areas if the API times out while calculating your request. The data will still be delivered as requested.*  
    </span>![DCDB_Order_CSB_Data_Popup.png](https://cms-kb.marine.usf.edu/uploads/images/gallery/2026-08/dcdb-order-csb-data-popup.png)
7. <span style="font-size: 12.0pt; line-height: 115%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: minor-bidi; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">Depending on the current volume of requests and the size of your requested area, you should receive an email with a link to download your data within a few minutes.</span>

<p class="callout success"><span style="font-size: 12.0pt; line-height: 115%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: Calibri; mso-fareast-theme-font: minor-latin; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: minor-bidi; mso-ansi-language: EN-US; mso-fareast-language: EN-US; mso-bidi-language: AR-SA;">Your CSB data are now downloaded and ready to have [Pydro tidal corrections](https://cms-kb.marine.usf.edu/books/crowdsourced-bathymetry-manual-working-version/page/pydro-tidal-corrections "Pydro tidal corrections") applied.</span></p>

# Pydro tidal corrections

<p class="callout info">Support Contact: Anthony Klemm, NOAA Office of Coast Survey  
<span style="mso-spacerun: yes;"> </span>anthony.r.klemm@noaa.gov </p>

<p class="callout warning">A Windows operating system is currently required to use Pydro Explorer</p>

Perform the following steps to process CSB data extracted from NCEI/DCDB to correct for tides and data-derived vessel transducer offset values:

1. You will need to download the **Pydro** software [here](https://svn.pydro.noaa.gov/Docs/html/Pydro/downloads.html) (supplemental downloads not required, just the base download).
2. Follow the [Data Extraction](https://cms-kb.marine.usf.edu/books/crowdsourced-bathymetry-manual-working-version/page/nceidcdb-data-extraction "NCEI/DCDB data extraction") instructions to retrieve the data you want to process.
3. When you receive the email link from NCEI, download the data and save it in an appropriate location.
4. Open **Pydro Explorer**, navigate to the ‘**BETA/EXPERIMENTAL**’ section of the Applications pane, and select ‘**CSB Processing.’**

**<span style="mso-no-proof: yes;">![](https://cms-kb.marine.usf.edu/uploads/images/gallery/2026-01/embedded-image-1tuvpkbj.png)</span>**

5. Click '**Run Program**'. You’ll see a Windows terminal execute the python environment and a GUI should eventually pop up.

<span style="mso-no-proof: yes;">![](https://cms-kb.marine.usf.edu/uploads/images/gallery/2026-01/embedded-image-ybj5xr8n.png)</span>

<p class="callout warning">If no GUI pops up, open the command line window to check if the following error was encountered:   
`ModuleNotFoundError: No module named 'pyfes' `  
</p>

To resolve this error, enter the following line of code: `conda install -c conda-forge pyfes -y`

![image.png](https://cms-kb.marine.usf.edu/uploads/images/gallery/2026-09/scaled-1680-/nLqimage.png)<span style="mso-no-proof: yes;"></span>

<span style="mso-no-proof: yes;">When the install is complete, close and re-open **Pydro Explorer,** navigate to the **CSB Processing** tool and click **Run Program** again. The GUI should pop up.</span>

6. In the popup window: 
    - **(1)** Locate and select the **Folder** containing the file you downloaded from NCEI; navigate to the Tide Zone file (see file path provided below); and specify an output folder. 
        - - - **Note:** make sure the input **Folder** you select contains only the data you wish to process, the tool will process all CSV files located in the folder.
    - **(2)** <span style="text-decoration: underline;">C</span><span style="text-decoration: underline;">heck</span> the box to use automated BlueTopo data (unless a BAG/GeoTIFF of bathymetry covering the area of interest is available).
    - **(3)** Leave the default settings checked and set the desired grid resolution **(5-10 m)** for your workflow.

<p class="callout warning">For use outside the United States, the CSB Processing tool has an option to use a global tide model (AVISO+ FES2022b) to resolve/correct depths to approximate Lowest Astronomical Tide (approx LAT).   
  
Inside United States waters, it is recommended (but not required) to use the Discrete Tide Zoning model option instead.</p>

<p class="callout info">**US Tide Zone .shp location:** C:\\Pydro24\\NOAA\\site-packages\\Python3\\svn\_repo\\HSTB\\CSB\_processing\\BETA\_subordinate\_tide\_zones\\tide\_zone\_polygons\_new\_WGS84\_merge.shp</p>

![image.png](https://cms-kb.marine.usf.edu/uploads/images/gallery/2026-09/scaled-1680-/19Zimage.png)

7. Click '**Start** **Processing**' and allow it to run. You can watch processing progress in the command line window. The application window will close when processing is complete.

<span style="mso-no-proof: yes;">![](https://cms-kb.marine.usf.edu/uploads/images/gallery/2026-01/embedded-image-c2qezyul.png)</span>

<p class="callout success">Your CSB data are now tide corrected and have been output in a GeoPackage (.gpkg) that can be [visualized using GIS software](https://cms-kb.marine.usf.edu/books/crowdsourced-bathymetry-manual-working-version/chapter/data-visualization "Data Visualization").</p>