Land surveying encompasses cadastral surveying, cartography, engineering surveying, hydrographic surveying and oceanographic surveying. Oceanographic, seismographic and hydrographic surveys were completed after each nuclear blast. The Icelandic Coast Guard is responsible for hydrographic surveying and nautical charting. Nautical charts are based on hydrographic surveys. These variables may be hydrographic, meteorological, and geographic. LiDAR are also in use in hydrographic surveying. Navies also undertake hydrographic surveys and intelligence gathering. Hurd developed the specialism of Royal Navy hydrographic surveyors. The IHO develops hydrographic and nautical charting standards. Tidal data for coastal areas is published by national hydrographic services. The CCG also operates all Federal scientific research and hydrographic survey vessels. The system was effectively utilized for the purpose of hydrographic survey and dredging. Nautical charts are issued by power of the national hydrographic offices in many countries. A hydrographic survey ship is a vessel designed to conduct hydrographic research and survey. It has applications in land survey, hydrographic survey, and in unmanned aerial vehicle navigation.