International Hydrographic Organisation (IHO) World Hydrographic Day

“Hydrography – underpinning the digital twin of the ocean”

21 June 2023


The 2023 theme is designed to showcase the digital twin of the ocean aims to develop a consistent, high-resolution, multidimensional and near real-time virtual representation of the ocean that could make ocean knowledge open-access, available to citizens, scientists and policy-makers around the world, and will provide a platform for global cooperation. The theme for WHD is designed to highlight the relationship between hydrography and oceanography, and how hydrography can play a key role in developing the digital twin of the ocean.


In November 2005, the United Nations adopted Resolution A/60/30, which includes the statement:

“…Welcomes the adoption by the International Hydrographic Organization of the World Hydrography Day, to be celebrated annually on 21 June, with the aim of giving suitable publicity to its work at all level and of increasing the coverage of hydrographic information on a global basis, and urges all States to work with that organization to promote safe navigation, especially in the areas of international navigation, ports and where there are vulnerable or protected marine areas.”

The World Hydrographic Day (WHD) theme, as in previous years, is intended to provide a broad range of opportunities to publicize the hydrographic work and services provided by national hydrographic offices, industry stakeholders and expert contributors, as well as the scientific community. The relevant topics include, but are not limited to:

  •  All commercial shipping is now going fully digital.

  •  To complete our image of the earth and make best use of it.

  •  The Work and Contribution of Hydrographers.

  •  100th anniversary of the formation of the International Hydrographic Organisation (IHO).

In support of WHD 2023, the IHO Secretariat will feed the IHO Facebook page, Twitter account, LinkedIn account and YouTube channel. In addition, the IHO Secretariat will organize a dedicated page on the IHO website, where papers and other material relevant to the celebration will be posted. Member States and Stakeholders are invited to forward to the Secretariat any material that they may create in support of their national WHD 2021 celebrations for posting on any of these platforms.

Additional information can be found on the IHO website.