What is true about the global network of tide gauges?

The statement regarding the global network of tide gauges being the most historical and precise source of sea level data is correct. Tide gauges have been used for over a century, providing a long-term record of sea level changes. They are installed at various locations around the world, making it possible to detect trends and variations in sea level over extended periods. This historical aspect is crucial for studying climate change, as it allows scientists to analyze past data to understand how sea levels have been influenced by various factors over time.

While there are more advanced technologies available, such as satellite altimetry, tide gauges still provide an essential ground-truth reference that complements and validates satellite data. Their reliable readings are vital for applications in coastal management, navigation, and understanding environmental changes.

The other options present less accurate characteristics of the tide gauge network. For example, while it serves coastal regions, its coverage is not exclusively focused on them. Additionally, the distribution of tide gauges is not considered comprehensive or uniform globally; there are regions with sparse data, such as parts of the Pacific and Indian Oceans. Lastly, tide gauges do not rely solely on satellite technology; they typically use mechanical or electronic means to measure water levels directly.