Overall Green Tropical Cyclone alert for SANBA-18 in Philippines, Palau from 08 Feb 2018 18:00 UTC to 12 Feb 2018 06:00 UTC

GDACS is a cooperation framework between the United Nations, the European Commission and disaster managers worldwide to improve alerts, information exchange and coordination in the first phase after major sudden-onset disasters.

Overall Green alert Tropical Cyclone for SANBA-18

in Philippines, Palau

click on

to select bulletin time

Meteorological source:

GDACS JTWC

Impact Single TC

Impact based on all weather systems in the area

Impact

Tropical Cyclone SANBA-18 can have a low humanitarian impact based on the maximum sustained wind speed,exposed population and vulnerability.

Meteorological source	GDACS
Exposed countries	Philippines, Palau
Exposed population	No people in Category 1 or higher
Maximum wind speed	139 km/h
Maximum storm surge	0.3 m (13 Feb 15:00 UTC)
Vulnerability	Medium (Philippines)

GDACS Score

GDACS alert score for Tropical Cyclones is 0.5 (GREEN Alert), 1.5 (ORANGE Alert), 2.5 (RED Alert)
For more info on GDACS alert score click here.

	Wind	Storm surge	Rainfall	GDACS score
Current	74 km/h	0.3 m	n.a.	0.5
Overall	139 km/h	0.3 m	n.a.	0.5
Maximum winds, storm surge, rainfall (Current: over the next 72 h, Overall: entire TC track) based on GDACS impact

TOP

Wind

74 km/h Current Max.

Up to 23.3 million people in Tropical Storm strength or higher (see SSHS)

Impact Timeline

N°	Date (UTC)	Max Winds (km/h)	Population in Tropical Storm or higher	Population in Cat 1. or higher	Countries
1	08 Feb 2018 18:00	93	41.5 million	No people	Palau, Philippines
2	09 Feb 2018 00:00	83	48.5 million	No people	Palau, Philippines
3	09 Feb 2018 06:00	93	34.9 million	No people	Palau, Philippines
4	09 Feb 2018 12:00	93	37.1 million	No people	Palau, Philippines
5	09 Feb 2018 18:00	93	35.3 million	No people	Palau, Philippines
6	10 Feb 2018 00:00	74	44.9 million	No people	Palau, Philippines
7	10 Feb 2018 06:00	74	34.2 million	No people	Philippines, Malaysia
8	10 Feb 2018 12:00	74	24.5 million	No people	Palau, Philippines, Malaysia
9	10 Feb 2018 18:00	139	44.2 million	4.2 million	Philippines
10	11 Feb 2018 00:00	83	39.8 million	2.5 million	Philippines
11	11 Feb 2018 06:00	83	47 million	No people	Palau, Philippines
12	11 Feb 2018 12:00	83	42.4 million	No people	Palau, Philippines
13	11 Feb 2018 18:00	83	48.4 million	No people	Palau, Philippines, Malaysia
14	12 Feb 2018 00:00	74	45.7 million	No people	Palau, Philippines
15	12 Feb 2018 06:00	74	23.3 million	No people	Palau, Philippines, Malaysia

Bulletin Timeline

N°	Date (UTC)	Category (SSHS)	Max winds (km/h)	Population in Cat.1 or higher	Population in Tropical Storm or higher	Location (lat, lon)	Countries
1	08 Feb 2018 18:00	Tropical depression	37	no people	no people	10.8, 147.8
2	09 Feb 2018 00:00	Tropical depression	46	no people	no people	11, 147.3
3	09 Feb 2018 06:00	Tropical depression	56	no people	no people	10.5, 146
4	09 Feb 2018 12:00	Tropical depression	56	no people	no people	10.1, 144.9
5	09 Feb 2018 18:00	Tropical depression	46	no people	no people	10, 143.6
6	10 Feb 2018 00:00	Tropical depression	46	no people	no people	8.8, 143.4
7	10 Feb 2018 06:00	Tropical depression	46	no people	no people	7.8, 141.8
8	10 Feb 2018 12:00	Tropical depression	56	no people	no people	6.7, 139.7
9	10 Feb 2018 18:00	Tropical storm	83	no people	21000 people	6.6, 137.2	Palau
10	11 Feb 2018 00:00	Tropical storm	65	no people	21000 people	6.6, 137.5	Palau
11	11 Feb 2018 06:00	Tropical storm	65	no people	21000 people	6.9, 135.9	Palau
12	11 Feb 2018 12:00	Tropical storm	65	no people	21000 people	7, 134.3	Palau
13	11 Feb 2018 18:00	Tropical storm	65	no people	<1000 people	7.4, 133.2
14	12 Feb 2018 00:00	Tropical storm	65	no people	no people	7.1, 132.1
15	12 Feb 2018 06:00	Tropical storm	65	no people	1.1 million people	6.9, 130.6	Philippines
15	12 Feb 2018 18:00	Tropical storm	74	no people	15.1 million people	7.7, 127.7	Philippines
15	13 Feb 2018 06:00	Tropical storm	65	no people	18.7 million people	8.5, 124.9	Philippines
15	13 Feb 2018 18:00	Tropical storm	65	no people	5.6 million people	8.4, 122	Philippines
15	14 Feb 2018 06:00	Tropical storm	65	no people	890000 people	8.4, 119.3	Malaysia
15	15 Feb 2018 06:00	Tropical depression	56	no people	no people	9.3, 115.3
15	16 Feb 2018 06:00	Tropical depression	56	no people	no people	10.5, 112.3
15	17 Feb 2018 06:00	Tropical depression	46	no people	no people	11.1, 109.5	Viet Nam

Actual track of the current bulletin

The alert for forecast greater than 3 days is limited to Orange level.

Download:

Exposed population - AoIs

Exposed population in the potential affected countries, provinces and populated places

Countries

Country
Palau
Philippines
Malaysia

Provinces

Region Province	Country
Palau	Palau
Southern Mindanao	Philippines
Northern Mindanao	Philippines
Central Mindanao	Philippines
Central Visayas	Philippines
Western Mindanao	Philippines
Western Visayas	Philippines
Southern Tagalog	Philippines
Sabah	Malaysia

Populated places

Name	Region Province	Country	City class	Population
Koror	Palau	Palau	City	11000 people
Melekeok		Palau	Capital	<1000 people
Tagum	Southern Mindanao	Philippines	City	170000 people
Davao	Southern Mindanao	Philippines	Major city	1.2 million people
Butuan	Northern Mindanao	Philippines	City	250000 people
Malaybalay	Northern Mindanao	Philippines	City	61000 people
Cagayan de Oro	Northern Mindanao	Philippines	City	-
Mambajao	Northern Mindanao	Philippines	City	10000 people
Cotabato	Central Mindanao	Philippines	City	180000 people
Marawi	Central Mindanao	Philippines	City	140000 people
Iligan	Central Mindanao	Philippines	City	260000 people
Oroquieta	Northern Mindanao	Philippines	City	39000 people
Tambulig	Western Mindanao	Philippines	City	7400 people
Pagadian	Western Mindanao	Philippines	City	130000 people
Dipolog	Western Mindanao	Philippines	City	93000 people
Argao	Central Visayas	Philippines	City	6100 people
Dumaguete	Central Visayas	Philippines	City	110000 people
Zamboanguita	Negros Oriental	Philippines	City	6100 people
Tanjay	Central Visayas	Philippines	City	39000 people
Zamboanga	Western Mindanao	Philippines	City	460000 people
Puerto Princesa		Philippines	City	160000 people

Critical infrastructure

Airports, ports, nuclear plants and hydrodams at risk, if affected, are listed below.

Airports

Name	IATA Code	Elevation (m)	Usage	Runway type	IFR	Runway Length (ft)
A.B. Won Pat International		6				0
Peleliu		3				0
Airai	ROR	54	Civ.	Paved	Yes	7200
Baganga	BNQ	unknown				0
Imelda Romualdez Marcos	MXI	47	Civ.	Paved	No	4200
Bislig	BPH	3	Civ.	Paved	No	3900
Tandag	TDG	5	Civ.	Paved	No	4400
Francisco Bangoy International	DVO	27	Civ.	Paved	Yes	8200
Butuan	BXU	43	Civ.	Paved	No	6000
Malaybalay		625	Civ.	Unpaved	No	3100
Nonoc		4				0
Surigao	SUG	6	Civ.	Paved	No	5000
Lumbia	CGY	186	Civ.	Paved	Yes	7800
Camiguin	CGM	5	Civ.	Paved	No	4200
Awang	CBO	58	Civ.	Paved	No	6200
Maria Cristina	IGN	396	Civ.	Paved	No	4500
Malabang	MLP	8	Civ.	Paved	No	4200
Ozamis	OZC	5	Civ.	Paved	No	4200
Pagadian	PAG	2	Civ.	Paved	No	5500
Tagbilaran	TAG	5	Civ.	Paved	No	4100
Dipolog	DPL	4	Civ.	Paved	No	6100
Siquijor		27				0
Dumaguete	DGT	5	Civ.	Paved	No	6100
Ipil	IPE	unknown				0
Basay Cdcp		101				0
Siocon	XSO	unknown				0
Zamboanga International	ZAM	9	Civ.	Paved	Yes	8500
Cagayan de Sulu	CDY	30				0
Puerto Princesa International	PPS	6	Civ.	Paved	Yes	8500
Kudat	KUD	unknown				0

Ports

Name	LOCODE	Country
Malakal Harbor		Palau
Caraga		Philippines
Mati	PHMXI	Philippines
Bislig / Mindanao	PHBPH	Philippines
Lamon Anchorage		Philippines
Hinatuan		Philippines
Monserat		Philippines
Aras Asan		Philippines
Tandag		Philippines
Tambungon		Philippines
Davao	PHBIY	Philippines
Talomo		Philippines
Daliao		Philippines
Butuan		Philippines
Nasipit	PHNAS	Philippines
Nasipit	PHNAS	Philippines
Odiongan		Philippines
Gingoog	PHGIN	Philippines
Surigao	PHSUG	Philippines
Villanueva	PHVNV	Philippines
Tagoloan Mis. Or / Cagayan de Or	PHTGO	Philippines
Cagayan de Oro	PHCGY	Philippines
Mambajao		Philippines
Cotabato	PHCBO	Philippines
Polloc	PHPLC	Philippines
Iligan	PHIGN	Philippines
Malabang		Philippines
Guindulman Bay		Philippines
Jagna		Philippines
Ozamis	PHOZC	Philippines
Jijimenez	PHJNZ	Philippines
Oroquieta		Philippines
Inamucan Bay		Philippines
Baliango		Philippines
Pagadian		Philippines
Tagbilaran	PHTAG	Philippines
Lazi		Philippines
Maribojoc		Philippines
Pulauan		Philippines
Dipolog		Philippines
Margosatubig		Philippines
Dumaguete	PHDGT	Philippines
Alicia		Philippines
San Sebastian		Philippines
Subanipa		Philippines
Bais / Dumaguete	PHBAI	Philippines
Santa Clara		Philippines
Tolong / Dumaguete	PHTLG	Philippines
Bayawan		Philippines
Puerto Santa Maria		Philippines
Zamboanga	PHBLU	Philippines
Sibuco		Philippines
Recodo		Philippines
Babuyan		Philippines
Puerto Princesa	PHPPS	Philippines
Quezon		Philippines
Eran		Philippines
Punta Baja Harbor		Philippines
Rio Tuba		Philippines
Bono Bono		Philippines
Balabac		Philippines
Kudat	MYKUD	Malaysia

Dams

Reservoir	Dam Name	River	Year
	Pulangi 4	Pulangi	1986

TOP

Rainfall

Rainfall accumulation of the past 24h, as detected by the Global Precipitation Measurement mission of NASA. For more information, see https://www.nasa.gov/mission_pages/GPM/main/index.html.

...

TOP

StormSurge

0.3 m

The maximum Storm surge height is 0.3m in Jaro, Philippines. This height is estimated for 13 Feb 2018 15:00 UTC .

The JRC has developed an experimental global storm surge model. The calculations are published about 20 minutes after a new advisory is detected by GDACS. The calculations identify the populated places affected by storm surge up to three days in advance, using the forecasted track. When forecasts change, the associated storm surge changes too and alert levels may go up or down. All links, data, statistics and maps refer to the latest available calculation. If the calculation for the last advisory is not completed, the latest available calculation is shown.

Locations affected by Storm surge (172 locations). Calculation based on advisory number 15 of 12 Feb 2018 06:00:00 UTC. (Simulation using 0.5 minute resolution)

Alert	Date (UTC)	Name	Country	Storm surge height (m)
	13 Feb 2018 15:00	Jaro	Philippines	0.3
	13 Feb 2018 15:00	Valencia	Philippines	0.3
	13 Feb 2018 15:00	Sum-ag	Philippines	0.3
	13 Feb 2018 15:00	Bacolod	Philippines	0.3
	13 Feb 2018 15:00	Talisay	Philippines	0.3
	13 Feb 2018 00:00	Bislig	Philippines	0.3
	13 Feb 2018 00:00	Mangagoy	Philippines	0.3
	13 Feb 2018 17:00	Anilao	Philippines	0.3
	13 Feb 2018 17:00	Silay	Philippines	0.3
	13 Feb 2018 17:00	Saravia	Philippines	0.3
	13 Feb 2018 17:00	Barotac Viejo	Philippines	0.3
	13 Feb 2018 17:00	Culasi	Philippines	0.3
	13 Feb 2018 00:00	Otiela	Philippines	0.3
	13 Feb 2018 16:00	Estado	Philippines	0.3
	13 Feb 2018 16:00	Victorias	Philippines	0.3
	14 Feb 2018 15:00	Brookes Point	Philippines	0.3
	14 Feb 2018 15:00	Lara	Philippines	0.3
	14 Feb 2018 15:00	Barongbarong	Philippines	0.3
	13 Feb 2018 17:00	Ajuy	Philippines	0.2
	14 Feb 2018 15:00	Tacbolubu	Philippines	0.2
	14 Feb 2018 15:00	Buligay	Philippines	0.2
	14 Feb 2018 14:00	Karasanan	Philippines	0.2
	13 Feb 2018 01:00	San Juan	Philippines	0.2
	14 Feb 2018 14:00	Labog	Philippines	0.2
	13 Feb 2018 17:00	Punta Buri	Philippines	0.2
	14 Feb 2018 17:00	Bulaloe	Philippines	0.2
	13 Feb 2018 00:00	Lawigan	Philippines	0.2
	13 Feb 2018 17:00	Kabasalan	Philippines	0.2
	14 Feb 2018 16:00	Banua	Philippines	0.2
	14 Feb 2018 16:00	Conduaga	Philippines	0.2
	14 Feb 2018 17:00	Males	Philippines	0.2
	14 Feb 2018 14:00	Panitan	Philippines	0.2
	13 Feb 2018 16:00	Gusem	Philippines	0.2
	13 Feb 2018 16:00	Timbang	Philippines	0.2
	13 Feb 2018 16:00	Kumalarang	Philippines	0.2
	12 Feb 2018 22:00	San Antonio	Philippines	0.1
	12 Feb 2018 23:00	Cateel	Philippines	0.1
	13 Feb 2018 07:00	Ipanon	Philippines	0.1
	13 Feb 2018 07:00	Cagayan de Oro	Philippines	0.1
	13 Feb 2018 07:00	Gusa	Philippines	0.1
	13 Feb 2018 14:00	Tabon	Philippines	0.1
	13 Feb 2018 14:00	Motibot	Philippines	0.1
	13 Feb 2018 17:00	Titanmanobog	Philippines	0.1
	14 Feb 2018 17:00	Sarimog	Philippines	0.1
	14 Feb 2018 17:00	Tarusan	Philippines	0.1
	14 Feb 2018 17:00	Iwahig	Philippines	0.1
	14 Feb 2018 17:00	Bonobono	Philippines	0.1
	14 Feb 2018 17:00	Malihud	Philippines	0.1
	14 Feb 2018 14:00	Aboabo	Philippines	0.1
	14 Feb 2018 14:00	Calategas	Philippines	0.1
	13 Feb 2018 18:00	Talisay	Philippines	0.1
	12 Feb 2018 23:00	Barcelona	Philippines	0.1
	13 Feb 2018 07:00	Igpit	Philippines	0.1
	13 Feb 2018 07:00	Opol Tagoloan	Philippines	0.1
	13 Feb 2018 07:00	Bugo	Philippines	0.1
	13 Feb 2018 07:00	San Martin	Philippines	0.1
	13 Feb 2018 07:00	Balingasag	Philippines	0.1
	13 Feb 2018 09:00	Initao	Philippines	0.1
	13 Feb 2018 09:00	Tubigan	Philippines	0.1
	13 Feb 2018 10:00	Clarin	Philippines	0.1
	13 Feb 2018 09:00	Camp Overton	Philippines	0.1
	13 Feb 2018 09:00	Iligan	Philippines	0.1
	13 Feb 2018 09:00	Dogui-ongan	Philippines	0.1
	13 Feb 2018 13:00	Dohinob	Philippines	0.1
	13 Feb 2018 18:00	Ipil	Philippines	0.1
	14 Feb 2018 17:00	Canipaan	Philippines	0.1
	13 Feb 2018 13:00	Roxas	Philippines	0.1
	13 Feb 2018 12:00	Katipunan	Philippines	0.1
	11 Feb 2018 14:00	Angaur	Palau	0.1
	11 Feb 2018 13:00	Attalabul	Palau	0.1
	11 Feb 2018 13:00	Ngalkol	Palau	0.1
	13 Feb 2018 19:00	Avila	Philippines	0.1
	12 Feb 2018 23:00	Lingig	Philippines	0.1
	12 Feb 2018 23:00	San Rafael	Philippines	0.1
	13 Feb 2018 09:00	Manticao	Philippines	0.1
	13 Feb 2018 09:00	Naawan	Philippines	0.1
	13 Feb 2018 09:00	Dalipuga	Philippines	0.1
	13 Feb 2018 11:00	Plaridel	Philippines	0.1
	13 Feb 2018 11:00	Lopez Jaena	Philippines	0.1
	13 Feb 2018 10:00	San Vicente	Philippines	0.1
	13 Feb 2018 10:00	Oroquieta	Philippines	0.1
	13 Feb 2018 10:00	Caputol	Philippines	0.1
	13 Feb 2018 10:00	Mohon	Philippines	0.1
	13 Feb 2018 10:00	Jimenez	Philippines	0.1
	13 Feb 2018 11:00	Baliangao	Philippines	0.1
	13 Feb 2018 11:00	Bato	Philippines	0.1
	13 Feb 2018 11:00	Usokan	Philippines	0.1
	13 Feb 2018 13:00	Linay	Philippines	0.1
	13 Feb 2018 14:00	Disakan	Philippines	0.1
	13 Feb 2018 13:00	Manukan	Philippines	0.1
	13 Feb 2018 16:00	Liloy	Philippines	0.1
	13 Feb 2018 15:00	Salug	Philippines	0.1
	13 Feb 2018 15:00	Lipakan	Philippines	0.1
	13 Feb 2018 15:00	Palandoc	Philippines	0.1
	13 Feb 2018 15:00	Bacangan	Philippines	0.1
	13 Feb 2018 17:00	Limbungahan	Philippines	0.1
	13 Feb 2018 21:00	Kampong Tabanka	Malaysia	0.1
	13 Feb 2018 21:00	Bokara	Malaysia	0.1
	13 Feb 2018 21:00	Kampong Tanah Merah	Malaysia	0.1
	13 Feb 2018 21:00	Sandakan	Malaysia	0.1
	13 Feb 2018 12:00	Dipolog	Philippines	0.1
	13 Feb 2018 12:00	Polanco	Philippines	0.1
	13 Feb 2018 16:00	Dumanquilas B	Philippines	0.1
	14 Feb 2018 14:00	Calabugas	Philippines	0.1
	13 Feb 2018 15:00	Pulupandan	Philippines	0.1
	13 Feb 2018 19:00	Banate	Philippines	0.1
	12 Feb 2018 23:00	Hinatuan	Philippines	0.1
	12 Feb 2018 23:00	Boston	Philippines	0.1
	12 Feb 2018 22:00	Kinablangan	Philippines	0.1
	12 Feb 2018 22:00	Dapnan	Philippines	0.1
	13 Feb 2018 09:00	Lugait	Philippines	0.1
	13 Feb 2018 11:00	Dampalan	Philippines	0.1
	13 Feb 2018 10:00	Bongbong	Philippines	0.1
	13 Feb 2018 10:00	Ozamiz	Philippines	0.1
	13 Feb 2018 10:00	Kolambugan	Philippines	0.1
	13 Feb 2018 10:00	Kolasihan	Philippines	0.1
	13 Feb 2018 10:00	Balugohay	Philippines	0.1
	13 Feb 2018 10:00	Kauswagan	Philippines	0.1
	13 Feb 2018 10:00	Lapayan	Philippines	0.1
	13 Feb 2018 10:00	Matungao	Philippines	0.1
	13 Feb 2018 10:00	Buru-un	Philippines	0.1
	13 Feb 2018 09:00	Mandulog	Philippines	0.1
	13 Feb 2018 18:00	Caparan	Philippines	0.1
	13 Feb 2018 18:00	Tambanan	Philippines	0.1
	13 Feb 2018 15:00	Tandu Patan	Philippines	0.1
	13 Feb 2018 15:00	Batu	Philippines	0.1
	14 Feb 2018 17:00	Summerumsum	Philippines	0.1
	14 Feb 2018 18:00	Wangle	Philippines	0.1
	14 Feb 2018 17:00	Sebaring	Philippines	0.1
	13 Feb 2018 12:00	Dapitan	Philippines	0.1
	13 Feb 2018 19:00	Iloilo	Philippines	0.1
	13 Feb 2018 19:00	Calaya	Philippines	0.1
	13 Feb 2018 16:00	Barcelona	Philippines	0.1
	12 Feb 2018 23:00	Pagtilaan	Philippines	0.1
	13 Feb 2018 08:00	Gitagum	Philippines	0.1
	13 Feb 2018 08:00	Lagindingan	Philippines	0.1
	13 Feb 2018 07:00	El Salvador	Philippines	0.1
	13 Feb 2018 07:00	Jasaan	Philippines	0.1
	13 Feb 2018 08:00	Dolong	Philippines	0.1
	13 Feb 2018 14:00	Sindangan	Philippines	0.1
	13 Feb 2018 16:00	Labason	Philippines	0.1
	13 Feb 2018 16:00	Dukanunday	Philippines	0.1
	13 Feb 2018 16:00	Kayok	Philippines	0.1
	13 Feb 2018 14:00	Lingawan	Philippines	0.1
	13 Feb 2018 17:00	Pananuran	Philippines	0.1
	13 Feb 2018 17:00	Mongamol	Philippines	0.1
	13 Feb 2018 17:00	La Libertad	Philippines	0.1
	13 Feb 2018 18:00	Ligian	Philippines	0.1
	13 Feb 2018 18:00	Surabay	Philippines	0.1
	13 Feb 2018 18:00	Buhangin Mahaha	Philippines	0.1
	13 Feb 2018 18:00	Cabatoan	Philippines	0.1
	13 Feb 2018 18:00	Gapol	Philippines	0.1
	14 Feb 2018 18:00	Rio Tuba	Philippines	0.1
	14 Feb 2018 18:00	Sarong	Philippines	0.1
	14 Feb 2018 19:00	Bogbog	Philippines	0.1
	14 Feb 2018 19:00	Silomsilom	Philippines	0.1
	14 Feb 2018 19:00	Ramos	Philippines	0.1
	14 Feb 2018 19:00	Loudan	Philippines	0.1
	14 Feb 2018 19:00	Pandanan	Philippines	0.1
	14 Feb 2018 19:00	Buliluyan	Philippines	0.1
	14 Feb 2018 19:00	Capandang	Philippines	0.1
	14 Feb 2018 19:00	Bacabaca	Philippines	0.1
	14 Feb 2018 19:00	Valdez	Philippines	0.1
	14 Feb 2018 19:00	Malatub	Philippines	0.1
	14 Feb 2018 19:00	Coral	Philippines	0.1
	13 Feb 2018 16:00	Margosatubig	Philippines	0.1
	13 Feb 2018 16:00	Maculay	Philippines	0.1
	14 Feb 2018 18:00	Sarap	Philippines	0.1
	13 Feb 2018 01:00	Lianga	Philippines	0.1
	13 Feb 2018 17:00	Malangas	Philippines	0.1
	14 Feb 2018 13:00	Batonbaton	Philippines	0.1
	14 Feb 2018 14:00	Eran	Philippines	0.1

Disclaimer
While we try everything to ensure accuracy, this information is purely indicative and should not be used for any decision making without alternate sources of information.
The JRC is not responsible for any damage or loss resulting from the use of the information presented on this website.
The designations employed and the presentation of material on the map do not imply the expression of any opinion whatsoever on the part of the European Union concerning the legal status of any country, territory or area or of its authorities, or concerning the delimitation of its frontiers or boundaries.