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What image comes to mind when you think of a “lighthouse”? Most likely, you picture a white tower standing on a cape.
Japan, being an island nation, has lighthouses installed throughout its coastline. While lighthouses were originally built as navigational aids, their white silhouettes against blue skies have become highly photogenic, making them popular tourist destinations in recent years. Whenever I travel to a place with a lighthouse, I make sure to visit and enjoy the scenic view of these beacons standing tall against the vast ocean.
Meanwhile, GPS technology has evolved significantly. From aircraft instruments to car navigation systems, and of course, ship navigation – GPS is now used and utilized for route confirmation in all forms of transportation.
So what role do lighthouses play in this modern era?
In this article, we’ll explore the current significance of lighthouses.
A lighthouse is a facility that emits light or radio waves to support safe navigation for ships at sea. They are typically installed along coastlines, on capes, at harbor entrances, and in areas with numerous reefs. Lighthouses serve as important markers for ships, helping them determine their position at night and in adverse weather conditions, and avoid dangerous waters.
Lighthouses serve three main functions:
Now that we’ve covered the fundamental roles of lighthouses, let’s explore their function and operation in modern society.
Today, with the widespread use of GPS and radar, ships can navigate without lighthouses. However, lighthouses remain crucial in areas where electronic devices malfunction or GPS signals can’t reach.
In Japan, while many lighthouses have become automated, their value as tourist attractions has increased, with some open to the public. Like the tourists who visit them, these lighthouses continue to inspire romance even after completing their original mission. Of course, some lighthouses remain operational while also being open to the public.
While it’s true that the relative importance of lighthouses has decreased with the development of GPS and other navigation support systems, they continue to serve as vital backup systems for ensuring safe navigation.
While writing this article, we spoke with lighthouse and navigation aid experts from the Public Interest Incorporated Association Tokokai about the role of modern lighthouses.
(Responses were received via email. We thank the Tokokai Secretariat for taking time from their busy schedule to respond to our questions.)
The role of lighthouses remains unchanged from 150 years ago, with their fundamental purpose being to provide positional information.
While mechanical aspects have been updated, the function of emitting light by focusing (amplifying) the bulb’s (light source) light through lenses remains unchanged from 150 years ago.
In providing positional information, what’s crucial is that navigators can “identify it as a lighthouse” and that “the lighthouse’s location and other details are clear.”
Regarding “identifying it as a lighthouse,” many lighthouses are painted white to prevent them from blending into the scenery from navigators’ viewpoint during daytime (called daytime marking effect).
At night, lighthouses are identified by their emitted light, and since each lighthouse has a different lighting pattern, they can be distinguished from one another.
Regarding “clarity of lighthouse location,” the lighthouse’s position, lighting pattern (characteristic), and color are published in government gazettes and recorded in nautical charts and light lists issued by the Maritime Safety Agency.
This allows navigators to accurately know which lighthouse they’re seeing and its location, enabling its use as a navigational aid.
The use as a navigational aid involves mariners determining their vessel’s position at sea, and for specific details, please refer to “Navigation Aids” on our association’s website.
Also, like aircraft, ships navigate by changing course (changing direction) at waypoints to head toward the next waypoint, so lighthouses play an important role as waypoint markers. It’s still common practice for ships to change course at points where they see a particular lighthouse at a specific bearing.
Similarly, lighthouses are used to warn that “when approaching the shore with lighthouse X at a certain bearing, there are dangerous shallows.”
Lighthouses installed on harbor breakwaters also function to indicate harbor entrances and breakwater presence.
In any case, these uses all utilize the lighthouse’s function of providing positional information.
Beyond positional information, major lighthouses also provide meteorological information.
Weather information was originally provided through manual observations by lighthouse staff, but this has now been automated.
Weather conditions observed at lighthouses (wind direction, speed, wave height, etc.) differ from general meteorological observation data and are essential information for navigators as key navigational reference points.
As explained above, while lighthouses’ basic role is providing positional information, with GPS’s advent, ships can automatically determine their position anywhere in the world’s oceans, eliminating the need to calculate position and course from lighthouse positions.
Naturally, this has reduced lighthouse necessity, but navigators still rely on visual navigation, and as a basic skill, they must maintain the ability to determine their position from lighthouse locations in case advanced navigation equipment blacks out.
In recent years, there’s been increasing movement to preserve historical lighthouses built during the late Edo to Meiji period modernization as regional historical and cultural heritage, utilizing them as tourism resources.
While this isn’t lighthouses’ original role, it serves an important function in passing down to future generations the testament of our predecessors’ dedication to supporting maritime transportation in our seafaring nation.
Currently, there are 16 lighthouses in Japan that visitors can climb.
While navigation support technologies like GPS and radar have advanced in recent years, lighthouses continue to play a vital role as backup systems in areas where radio waves can’t reach or when systems fail.
Besides their role as navigational aids, some lighthouses have been developed and opened to the public as tourist attractions, allowing visitors like us to enjoy their scenic beauty.
Even in this modern age of advanced positioning technologies like GPS and radar, the importance of lighthouses remains unchanged. Standing at the edge of continents, they brave the rough seas and continue to protect the safety of maritime travelers.
As tourists, understanding these aspects can make lighthouse visits more meaningful. Let’s appreciate the beautiful scenery while contemplating the vital mission that lighthouses continue to serve.
