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Eruption of the Hunga Tonga-Hunga Ha‘apai volcano (Tonga), 15 January 2022
The volcanic ash and the tsunami accompanying the eruption of the submarine volcano, Hunga
Tonga-Hunga Ha‘apai, located north of the main island of Tonga (GLIDE No. VO-2022-000005TON) caused great damages to houses and serious shortage of drinking water in Tonga. Tsunami
damages have also been reported in other Pacific countries.
ADRC as the secretariat of the Sentinel Asia Project, a project aiming for utilization of spacetechnology for DRR, requested emergency observation to assess the damage in Tonga, which isthe center of the damage, and to collect the latest information of the situation.
Asian Disaster Reduction Center, 22 Jan. 2022

Basic Information• The Kingdom of Tonga is located in South
Pacific Polynesia and consists of 171 islands(45 of which are inhabited). It has apopulation of about 100,000, of whom 70%
live on Tongatapu Island.

Photo 1: Hunga Tonga-Hunga Ha'apai island before the eruption (the outer rim of thehuge caldera submarine volcano formed the island) (Source: Google Maps)• The volcano Hunga Tonga-Hunga Ha'apai ispart of the volcanic arc that extends from Fiji
to New Zealand with eruptions recorded as
far back as the 12th century. In recent years,
the volcano erupted in March 2009 andNovember 2014-January 2015, and has
been active since December 2021.

https://www.google.com/maps/@-20.5447141,-175.4000813,4330m/data=!3m1!1e3?hl=en

Asian Disaster Reduction Center, 22 Jan. 2022

Volcanic activity on 22 January 2022
On 15 January 2022, ataround 17:00 (TOT, UTC+13)(13:00 JST), Hunga TongaHunga Ha'apai submarinevolcano erupted on a large
scale (volcanic explosion
index of about VEI 6). This
generated tsunamis. Largetidal level fluctuations due toair vibration were also
observed in Japan and other
Pacific countries.

Tonga
time
15 JAN
17:10
17:30
18:31
18:48
19:36
22:29

Japan
time
13:10
13:30
14:31
14:48
15:36
18:29

23:01

19:01

23:43

19:43

23:58

19:58

23:56
16 JAN
0:20

19:56

1:53

21:53

3:55
4:15
6:00
6:26

23:55
00:15
02:00
02:26

12:35

08:35

18:00

14:00

20:20

Natural phenomena

Status of response

Massive eruption occurs
1.2m Tsunami in Nuku Alofa, Tonga
60cm Tsunami in American Samoa
Tsunami Advisory for American Samoa
Tsunami Warning for American Samoa
10cm Tsunami in Hawaii
Japan Meteorological Agency: Slight Sea Level
ChangeTsunami Advisary for Hawaii
First wave of tsunami in Chichijima, JAPANADRC to SPC: Contact for Sentinel Asia activation.
First Tsunami Wave at Katsuura, JAPANTsunami Advisory for Aleutian Islands from west
coast of US
1.2m tsunami in Amami, JAPANJMA: Tsunami Warning and Tsunami Advisory
JMA: Press conference
1.1m Tsunami in Kuji, JAPANUNITAR activates international disaster charter
based on UNOCHA's request
JMA: Tsunami warning and advisory cancelled
Sentinel Asia activated based on ADRC's request

Table 1: Natural phenomena such as volcanoes, tsunamis, and sea level changes and the status of response(Source: extracted from the relevant organizations' websites)

Asian Disaster Reduction Center, 22 Jan. 2022

Eruption records
by Himawari 8(13:10-14:00)
The meteorological satellite
Himawari-8 acquires global images
every 10 minutes and those images
revealed the radius of the plume
was about 260 km and that airvibration had occurred.

Photo 2: Images of eruption recorded by Himawari 8 (13:10-14:00)(Source: JAXA Himawari) Monitor)

Asian Disaster Reduction Center, 22 Jan. 2022

Plume Altitude
According to the Ozone Mapping Program(OMPS) aboard NOAA's Suomi NPP
satellite, the maximum altitude of theplume is estimated to be 30 km, indicatingthat it has reached the stratosphere.

Figure 2: Altitude of the plume (Source: Volcano Discovery)
https://www.volcanodiscovery.com/hunga-tonga-hunga-haapai/news/170639/Hunga-Tonga-Hunga-Haapai-volcano-Tonga-activity-update-latest-measurements-confirmed-30-km-column-h.html

Asian Disaster Reduction Center, 22 Jan. 2022

Tsunami, atmospheric vibration generation andtidal level fluctuations• The tsunamis and tidal changes observed in the
Pacific Ocean are as follows: Amami, Kagoshima
1.2m; Kuji, Iwate 1.1m; Chichijima 0.9m (JMA); New
Caledonia 1.13m; Vanuatu 1.41m; Jackson Bay,New Zealand 0.91m; Chañaral, Chile 1.74m;
Galapagos, Chile 0.75m; Maui, Hawaii 0.83m, PortSan Luis, California 1.31m, King Cove, Alaska 1.0m(NOAA)• According to the official announcement by theGovernment of Tonga (@ConsulateKoT, Twitter, Jan.
18), the tsunami reached up to 15 meters on thewest coast of Tongatapu and Eua-Ha'apai islands.

Asian Disaster Reduction Center, 22 Jan. 2022

Effects of the Volcanic Activity• According to an official announcement by the Governmentof Tonga (@ConsulateKoT, Twitter, 18 January),
communications (including calls and internet) weredisabled until 17 January due to damage to the submarine
cable. Communication via satellite phone and wirelesscommunication was partially restored on 18 January.
Domestic communication was possible only in Tongatapu
and Eua.
• Search and rescue operations in the affected areas (AtataIsland and Ahau Village) began on the 16 January.

• Evacuation from Atata Island to Tongatapu Island and from
Mango Island and Fonoifua Island to Nokuma Island began.
• In the western part of Tongatapu Island, 21 houses werecompletely destroyed, 35 houses were badly damaged,
and other damages occurred in many places.

• The supply of drinking water has been severely affected byvolcanic ash.
• On 19 January, the Prime Minister officially declared astate of emergency.
Asian Disaster Reduction Center, 22 Jan. 2022

Emergency Observation
by Space Satellites• In response to the news of the eruption and tsunami, ADRC, whoserves as the Sentinel Asia Secretariat, approached SPC, theorganization in charge of the South Pacific region, to inquire about thepossibility of activating Sentinel Asia. SPC was unable to confirm dueto the local communication situation, so ADRC acted as the requestor
and activated Sentinel Asia on 16 January.
• The international disaster charter covering the entire world was alsoactivated on the 16th.

Figure 1: Sentinel Asia's emergency observation request information and pre-disaster archivehttps://sentinel-asia.org/EO/2022/article20220115TO.html

Asian Disaster Reduction Center, 22 Jan. 2022

Images of Hunga TongaHunga Ha’pai Island Afterthe Eruption by ALOS2
Satellite
Analysis of data taken by JAXA's
ALOS2 earth observation satellite
confirmed that the Hunga TongaHunga Ha’pai island disappeared
after the eruption, leaving only partof the island.

https://sentinelasia.org/EO/2022/article20220115TO.html

https://www.google.com/maps/@-20.5447141,175.4000813,4330m/data=!3m1!1e3?hl=en
Photo 3: Hunga Tonga-Hunga Ha’pai island after the eruption(Source: Sentinel Asia)

Asian Disaster Reduction Center, 22 Jan. 2022

Various data provided by the participatingorganizations of Sentinel Asia

Taiwan's space agency, NARL andThailand's space agency, GISTDA,
also provided a series of post-disaster
images to the Sentinel Asia website.

Figure 2: Data provided by Sentinel Asia.
https://sentinel-asia.org/EO/2022/article20220115TO.html

Asian Disaster Reduction Center, 22 Jan. 2022Analysis by Remote
Sensing Organizations
The results of damage analysis byEOS and MBRSC are available.

Figure 3: Products provided by Sentinel Asia.
https://sentinel-asia.org/EO/2022/article20220115TO.html

Asian Disaster Reduction Center, 22 Jan. 2022

Analysis by Earth
Observatory ofSingapore-Remote
Sensing Lab (18 January)• By analyzing data from theSentinel-1 satellite, buildings thatshowed great change before andafter the disaster were coloredfrom yellow to red.
• Colors in residential areas areconsidered to be damagedbuildings, while colors inagricultural areas may not
represent damage.

https://sentinel-asia.org/EO/2022/article20220115TO/EOS-RS_20220115_DPM/EOSRS_20220115_DPM_S1_Tonga_HungaTonga_Volcano_v0.9_MAIN.png

Asian Disaster Reduction Center, 22 Jan. 2022

Analysis by MBRSC,UAE Space Agency(21 January)• Data analysis from the Sentinel-2
satellite was used to create adamage map of western
Tongatapu island.
• Areas in red are areas estimatedto be damaged by tsunami. Areas
in purple are areas covered byvolcanic ash.

• Areas in orange are areas
considered to have observedpumice rafts.

https://sentinel-asia.org/EO/2022/article20220115TO/MBRSC/Kanokupolu-Map.jpg

Asian Disaster Reduction Center, 22 Jan. 2022

Analysis by MBRSC,UAE Dubai Government
Space Agency(21 January) (cont.)• By analyzing data from Sentinel2 satellite, pre- and post-disasterdamage maps of western
Tongatapu island were created.
• It can be estimated from themaps that vegetation has been
lost and buildings have been
washed away.

https://sentinel-asia.org/EO/2022/article20220115TO/MBRSC/Tsunami-Impact-Map-2.jpg

Asian Disaster Reduction Center, 22 Jan. 2022

[Ref.] Sentinel Asia project• In the event of a disaster, it is important to be able
to quickly assess the disaster area for emergency
response. Earth observation satellites effectively
serve this purpose by analysing the disaster areaand providing those data to the local community.
• ADRC continues to participate in the Sentinel Asia
project, which was launched in 2006 with anobjective of establishing a disaster risk
management system in Asia utilizing the satellite
images. ADRC functions as the focal point toreceive emergency observation request in theframework of the Sentinel Asia.
• Upon receiving a request, ADRC decides whether
the request is appropriate and whether theemergency observation should be implemented
mainly by assessing the damages and casualties.
• Based on its own judgement, ADRC will forward
the request to space agencies that participate in
the Sentinel Asia Project, namely: ISRO (India),JAXA (Japan), GISTDA (Thailand), NARL (Taiwan),
CRISP (Singapore), and MBRSC (United ArabEmirates).
Asian Disaster Reduction Center, 22 Jan. 2022