The free public tour at the Hong Kong Observatory is rumored to be very difficult for anyone to secure a spot. I was fortunate that I succeeded in signing up in my first attempt. On a rainy afternoon I headed to the Observatory with much anticipation. There was a short walk up a small hill. When I saw multiple families with children on the way, I knew I was at the observatory. It is indeed a very educational and fun activity for families with young children.

The History of the Hong Kong Observatory

Established in 1883, the Observatory was intended to be a site of observation of astronomical phenomena. As such, it was not, strictly speaking, a meteorological institute. The original intention of the Observatory was to assist maritime navigation by telling time and forecasting storms. And its name, the Hong Kong Observatory, has been used since, (as Royal Observatory between 1912 and 1997) to express the original intention of the institution.

Photo: The Hong Kong meridian was recently re-discovered at the Observatory after an inquiry made by a geographer during COVID.

The Hong Kong Observatory building is an antique monument. Built in 1884 in the Victorian-Colonial style, the building features two stories in a rectangular block with very classy verandas. The New Centennial Building next door has given home to the scientific wing of the Observatory since 1984.

There is a small exhibition gallery dedicated to showing the Observatory’s history, as well as some very interesting relics. It is part of the guided tour.

Interesting Facts about Typhoon Warnings

In our tour, we learned plenty of interesting facts about the weather forecasting function of the Observatory. I will discuss just a few of those lessons here. In the front patch, there are a number of functioning and nonfunctioning instruments related to weather forecasting. A set of enormous metal typhoon signals hang there. They are the very testament to how technology changes official practice, resulting in changes of the standard official language.

In a bygone time that I still remember, the Hong Kong Observatory’s language reporting typhoons references to the act of “hoisting,” as in “Typhoon Signal No. 8 has been hoisted.” Back in those days, the Hong Kong Observatory would actually hoist these very heavy metal-made typhoon signs on its pole on its Tsim Sha Tsui premise. Those were the days when this hillside location was a high point, where people in approaching ships and surrounding buildings could see the signs. Times have changed, and so has the urban face of Hong Kong. There is no longer any point in “hoisting” the typhoon signals now, as every single building in Tsim Sha Tsui has dwarfed the typhoon pole by now. The metal framed typhoon signs are simply relics these days, and the standard language for typhoons is “Typhoon Signal No. X has now been issued.”

Satellites Versus Radars

On the website of the Hong Kong Observatory, there are both satellite and radar images that indicate the movements of clouds, rainbands, and typhoons. It was only with the explanations given by our tour guides that I understood the difference.

The satellites detect the projected path of a storm. Satellite cameras can capture the accurate images of a storm system as viewed from space. Hong Kong does not have its own satellites, but the Hong Kong Observatory maintains relationships with the meteorological institutes abroad to obtain satellite images of storm systems.

The radar uses electronic signals that transmits through the air from the ground radar stations (where you see a giant white globes on tall mountains, those are radars). These transmissions will hit objects in the atmosphere and bounce back, resulting in data that can be interpreted to detect clouds, rain and tornadoes. The intensity of the reflected signal will indicate the severity of the weather condition being scanned.

There are three radar stations that belong to the Hong Kong Observatory, namely Tai Mo Shan, Tates Cairn and Tai Lam Chung. The one in Tai Lam Chung is used exclusively for the airport. Tai Mo Shan is for general use, and Tates Cairn is a backup radar.

The Front Patch

At the Observatory, one would easily be drawn to the beautiful colonial architecture of the old observatory building. But in fact, almost all of the scientific fact gathering takes place in the front patch.

The Precise Location of “The Observatory”

The Observatory’s standard language that references “so-and-so is situated at [distance] km [cardinal direction] of the Observatory” presents an interesting point of learning. From which point is this distance and cardinal direction measured? The answer is in the front patch. This short stone post in the photograph is what indicates the location of “the Observatory” in this statement. It is an actual, physical, identifiable point from which the distance and cardinal direction of a certain something is measured.

The Measurement of Rainfall Data

The issuance of the rainstorm signals depends on the hourly rainfall rate. For example, where the hourly rainfall rate has reached 30mm per hour, then the condition will warrant the issuance of the amber warning.

This data of hourly rainfall rate is collected with very simple instruments, and basically, buckets. During rainy days, the staff of the Observatory periodically come to the front patch and take the rainwater collected in the cup anemometer and tipping bucket to gauge the hourly rainfall. We had the pleasure to watch a staff removing the bucket when we were right at the front patch for this tour. The Observatory is capable of seismic detection as well, and this equipment is underground, also at the front patch.

The Administration of Weather Forecasting

A building that also looks very classic and colonial-styled stands next to the antique Observatory building. Although this is not an antique monument, it has enormous significance as the residency for the administration of the Observatory.

The inaugural Government Astronomer of the Hong Kong Observatory was Dr. William Doberck. The current Director is Dr. Chan Pak Wai. The administration of the Hong Kong Observatory is made up of the Director, Assistant Director and many science officers.

Throughout the Observatory’s history, most of the directors have lived in this building. There is a residency on site because Typhoons 8, 9, 10 and black rainstorm warning must be signed off by the director, and he is also required to be on duty throughout the whole time that these signals are in effect.

The Talents of the Hong Kong Observatory

Given the tour’s exceptionally educational nature, many children were keen at the presentation. The natural question thus arose. “What would one have to study in order to work at the observatory?”

There was no doubt that everybody at the observatory must have majored in physics. Nope, not geography or other kinds of science. Physics, and a heavy focus on math. All of the functions that the Hong Kong Observatory engages in require measurements and the interpretation of data. Physics and math are necessary.

To this day, the weather maps at the Observatory are still hand-drawn, four times daily. To be the weather artists at the Observatory, one must still have a physics degree.

Sign Up for the Free Public Tour at the Observatory

To sign up for a free public tour at the Observatory, visit this link here. When a tour has been full, the tour spots are assigned by lottery. It takes 1.5 hours to participate in this tour, and yes, it will take up a full 1.5 hours.

Source

The Guided Tour of the Hong Kong Observatory.

The Website of the Hong Kong Observatory.

Descriptions on site at the Hong Kong Observatory.