Today, June 21, is World Hydrography Day, dedicated to the science of surveying and charting land-surface bodies of water. This international observance day was introduced in 2006 through the efforts of the International Hydrographic Organization and supported by the UN General Assembly.

Hydrographers measure and describe physical characteristics of seas, oceans, rivers, lakes, and coastal areas. They also predict how our water bodies will change over time. Such research is needed for safe navigation, proper performance of all marine activities and, of course, for protection of the environment.

Over 70% of the globe surface is water, while we do not know much about this watery realm. There is a common phrase that our near space is better researched than the ocean. Indeed, while over 500 people have traveled to space, only a few people have reached the deepest parts (10 km deep) of the World Ocean.

The United Nations proclaimed the forthcoming years, 2021–2030, as Decade on Ecosystem Restoration. The UN resolution calls for support to and scaling up of efforts to prevent water pollution, halt and reverse the degradation of ecosystems worldwide and raise awareness of the importance of ecosystem restoration.

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