Miyake-jima: Why You Must Always Carry A Gas Mask When on the Island

When the summer season finally rolls in, it is typical for people to start dreaming about their next summer vacation. Most people would want to go to different islands with beautiful beaches and bask in the sun. A must things to do during these summer vacations is to get sun-kissed skin and basically just have a good time. For people traveling to Japan for a summer vacation, the country has a lot of islands that tourists can choose from. However, if one is looking for something different on an island, nothing would be more fitting other than Miyake-jima.

Basic Facts About Miyake-jima: Geography, Climate, Etc.

By Army Map Service, Corps of Engineers, U.S. Army [Public domain], via Wikimedia Commons

More commonly known as Miyake Island by foreign visitors, Miyake-jima is a volcanic island in Japan. Located in the Izu archipelago situated in the Philippine Sea, the island is estimated to be 180 kilometers, which is equivalent to 110 miles, away from the southeast portion of the island of Honshu. Despite the activities of the volcano on the island in recent years, the place is still inhabited by the people of Japan today. Similar to the other islands that are part of the Izu Island group, Miyake-jima serves as a portion of the Fuji-Hakone-Izu National Park. Other islands similar to Miyake-jima include Hachijojima and Mikurajima.

With the coordinates of 34.079° North and 139.529° East, the island has a total area of 55.44 square kilometers, which is equivalent to 21.41 square miles.  Its coastline spans 38.3 kilometers, which is equivalent to 23.8 miles. Its highest elevation is at 775.1 meters, which is equivalent to 2,543 feet. The highest point on the island is Mt. Oyama. The island is under Miyake Subprefecture, which is under the Tokyo Metropolis Prefecture.

With a granitic composite cone, Miyake-jima is a stratovolcano that dates back to the late Pleistocene era, which occurred sometime between 10,000 and 15,000 years ago. The coastline of the island creates a circular shape with an average radius of 4 kilometers. Mount Oyama is the active volcano on the island, which also serves as its highest elevation.  

Written records have been documented about the activities of this volcano that dates back to the Nara period. Since 500 years ago, Mt. Oyama has erupted 13 times with 5 of these eruptions occurring since the beginning of the Meiji period. 11 civilians were killed by a lava flow that occurred in the year 1940. Further eruptions followed in the year 1962 and 1983.

On the 14th of July in the year 2000, another series of eruptions occurred on the island. The activities of Mt. Oyama caused great destruction to the point that the residents completely evacuated the island in the month of September that same year. Volcanic emissions continued to occur for a period of four years. On the 1st of February in the year 2005, the island was inhabitable again. However, a continuous flow of sulfur dioxide gas continued to be emitted by the volcano after the eruption.

By Photaro (Own work) [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons

Because of this, carrying gas masks at all times were required for the residents of the island. While these masks need not be worn constantly, carrying one is just a precaution. Should there be a significant increase in the amount of toxic gases in the air, there would be alarms all over the island that would give out warnings to the residents. Detection of pre-eruptive degassing of rising magmas is done by a Multi-Component Gas Analyzer System. This system measures the volcanic gas that is emitted by the volcano and helps in enhancing prediction of volcanic activity.

With a Köppen climate classification Cfa, the island has a humid subtropical climate. The place experiences a  considerably warm summer season and a mild winter season. Precipitation is almost always present on the island though it is considerably lower during the winter season.

As of the 1st of June in the year 2016, the island has a population of 2,451. The local government of Miyake-jima is Miyake Village, also known as Miyake-mura in Japanese. A tel. number is available for people who wish to call the government office. This village further encloses Onoharajima, a small uninhabited island just southwest of Miyake-jima. Miyake Village is composed of five traditional hamlets. These hamlets include Izu, Igaya, Tsubota, Kamitsuki, and Ako. Tsubota serves as the administrative center of this group.

The rare endemic Izu thrush, also known as akakokko in Japanese, also thrives in the island of Miyake. Despite the volcanic acitivy in the area, the island still serves as a home to rich flora and fauna. A number of rare species of animals like bird also reside in this area. However, their natural habitat is constantly threatened not just by volcanic activities but by human activities as well. 

The Evacuation from and Resettlement in Miyake Island

With the population of 2,415 as of the 1st of June in the year 2016, the population density of Miyake-jima is 44.3 persons per square kilometer, which is equivalent to 114.7 persons per square mile. On the month of June in the year 2000, a series of earthquakes rocked the island of Miyake, with a huge volcanic eruption worsening the situation. At the peak of the volcanic activity that time, the volcano’s summit gushed lava fountains with hot gas and rock flowing and rushing down the slopes. Several layers of ash served as a blanket on the landscape surrounding the volcano while toxic gases emerged from the ground.

Within three months, the destruction caused by the volcanic activities of Mt. Oyama, as well as the potential harm it might cause to the inhabitants of the islands, forced the government to take actions. All the residents of the island were ordered for a mandatory evacuation on the month of September that same year. At the time, about 3,600 people were living on the island, most of which relocated to Tokyo following the horrifying event.

After five years, the volcanic activity of Mt. Oyama began to decrease. This prompted the authorities in Japan to conclude that the island is beginning to become a safe place again for people to reside in. Upon the relaxation of the evacuation order, thousands of people began to return to Miyake-jima.

As of the year 2015, the population in the island already amounted to 2,775 residents. The people again began living their lives as normal as can be. The major industries in the island include fishing, farming, and tourism. With children on the island, there are also a number of elementary and junior high schools in Miyake-jima, as operated in towns and villages.

Why Should We Carrying A Gas Mask At All Times on the Island

By NASA ASTER volcano archive jpl [Public domain], via Wikimedia Commons

While the residents are now allowed to live in Miyake-jima, the potential harm that the residents might suffer from is still apparent. While the intensity of the volcanic activity of Mt. Oyama has decreased through the years, the volcano still emits huge amounts of sulfur dioxide from time to time, which is a toxic gas. Because of this, residents, as well as tourists, in the island are required to carry a gas mask with them at all times. A third of the island still remains uninhabitable to this day. The minute the levels of sulfur dioxide in the air get too high, a system of alarm sirens shall sound off to alert the residents of the island.

An image of the island was taken on the 11th of February in the year 2015 by the Operational Land Imager or OLI on Landsat 8. The photo depicts the recovery of the forests within the island though broad barren patches of ash can still be seen around the caldera of the volcano. The towns and villages in the island as arranged so as to run along the coast of the island. A number of ports and an airport are some of the facilities that can also be seen in the image, which would be crucial in case of an emergency evacuation.

Carrying a gas mask while on the island is a requirement of the law. These gas masks shall be used as protection from sulfur dioxide. As soon as a caution or a warning alarm is announced, the people of Miyake-jima are required to put on the gas mask immediately. For people traveling to the island not carrying a gas mask, a simple one can be purchased at the Takeshiba Terminal as well as the Miyakejima Tourist Association Store.

Due to the high risk of life caused by the volcanic activities of Mt. Oyama, several studies have been made on the patterns of the volcano. It was found that Mt. Oyama goes off in 20-year intervals. One of the eruptions were so intense that it polluted the air with 42,000 tons of sulfur dioxide each day, which is highly toxic to living creatures that would be exposed to this gas even in less than an hour.

While many may not find the island an ideal place to visit, several tourists still find Miyake-jima an interesting island to check out. However, safety is still of utmost importance. Hence, foreign visitors are advised of the risks of going to Miyake-jima. Furthermore, they are briefed on the harmful effects of sulfur dioxide to the body and health of an individual. It is suggested that tourists undergo a respiratory medical exam prior to visiting the island. Moreover, the tourists must arrive on the island with a mask.

A Guide on Visiting Miyake Island

By NASA ASTER volcano archive jpl [Public domain], via Wikimedia Commons

Despite the risks, Miyake Island is still a beautiful place to see and visit. The place can be accessed by an overnight ferry such as the Sarubia Maru and the Camellia, which is under the operation of Tokai Kisen. The ferry leaves Takeshiba Pier, which is situated near Hamamatsucho Station in Tokyo, at 10:30 in the evening. The ferry arrives at the island of Miyake at 5 in the morning. The island also accepts flights in its airport.

Instead of looking at the worst case scenarios possible with Mt. Oyama, one would suggest looking at the bright side. Due to the volcanic activity on the island, a specific volcanic trail was created through the years since the many eruptions of the volcano. These trails are good for people who love to trek.

A number of short trekking routes are available all over the island for people to explore. To add safety, most of these volcanic trails are marked with safe walkways just to ensure that people would not fall off the deep end. Even beginners in trekking would find these trails manageable and relatively easy to trek.

Being an island, it is obvious that Miyake-jima is surrounded by beaches. One thing particular about the beaches in the island is its black sand. Its color can be attributed to the continuous volcanic activity in the past. The sand was caused by hot lava getting in contact with water then immediately cool that lets it break into sand and basalt fragments. Hence, for people looking for a different type of beach, this place might be the one.

Aside from the black sand beaches, food on the island is also a must-try. A famous milk biscuit cracker known as Senbei is produced by Okatairo honpo. The food is produced locally in the island and exported to Japan for all the other people to enjoy. Despite its simplicity, many people swear by its yummy goodness. Another local must-try is the shochu produced by Oyamaichi. Made from a mixture of sweet potato and a combination of grain, the shochu produced in this island contains a rough but natural flavor.

Last but certainly not the least, observe and learn more about wildlife at Miyake Nature Center. The island is actually quite well-known as a haven for bird-watching. Established in the year 1993, the center is operated by the village. Several bird watchers flock to the island just to be able to witness the beauty of the rare native Akakokko bird, also known as the Izu Thrush. For people who are not exactly bird watchers but would like to learn the ropes, a pair of binoculars can be borrowed from the Miyake Nature Center to watch birds from east to west. Another place worth checking out when in Miyake-jima would be the Tairo-ike Lake, a crater lake that was formed more than 2,000 years ago.