Mapping the Impacts of Typhoon Vamcoin Cagayan and Isabela
Geomatics for Environment and Development
MANILA OBSERVATORY
November 20, 2020

Summary• Typhoon Vamco––––

Landfall: Nov. 11, 2020
Diameter: 800 km
Rainfall: >200 mm
Places that received >200 mm of rain:••••

Cagayan and Isabela River Basin
Pampanga River Basin
Marikina Watershed
Pasig-Laguna Lake Watershed•
•
•
•
•
•

Flooded area in Cagayan and Isabela
River Basin: 1,443 km2
2
Flooded area in Cagayan: 870 km
2
Flooded area in Isabela: 543 km
Flooded population in Cagayan: 290,633
Flooded population in Isabela: 228,488
Most affected land cover types:–––––

1,224 km2 of annual cropland
88 km2 of inland water
37 km2 of open areas
28 km2 of built-up
19 km2 of perennial croplandTrack of Typhoon Vamco

Typhoon Vamco

With a diameter of roughly 800
km, Typhoon Vamco covered
the entire mainland of Luzon inthe Philippines. It made landfall
on Nov. 11, 2020 in Quezon,crossed Bulacan and Pampanga,and exited Zambales on Nov.
12, 2020.
Typhoon Vamco “Ulysses” (NDRRMC Situation Report No. 6)• Maximum sustained winds: 150 km/h
• Gustiness: 200 km/h
• First landfall: 10:30 of Nov. 11, 2020 in Patnungan, Quezon• Second landfall : 11:20 in Burdeos, Quezon• Third landfall: 1:40 am of Nov. 12, 2020 in General Nakar,Quezon
••
•
•
•

JTWC – Joint Typhoon Warning Center
NAMRIA – National Mapping and Resource Information Authority
NDRRMC – National Disaster Risk Reduction and Management Council
NOAA – National Oceanic and Atmospheric Administration
SRTM – Shuttle Radar Topography Mission••Affected watersheds:• Cagayan and Isabela
River Basin• Pampanga River Basin• Marikina River Basin• Pasig-Laguna LakeWatershed`

``

`
`

EORC – Earth Observation Research Center
JAXA – Japan Aerospace ExplorationAgency

 Typhoon Vamco “Ulysses” accumulated
24-hour rainfall satellite data
 Areas with heavy rainfall (>200 mm)
 Region II
 Quezon Pampanga Zambales
 Metro Manila, Rizal, Laguna
Image Source: Google Maps
18 Major River Basins & 3 Principal
River Basins in the PhilippinesLow-lying Areas in Cagayan and IsabelaTyphoon Vamco

•
••••
•

JTWC – Joint Typhoon
Warning CenterNDRRMC – National
Disaster Risk Reduction
and Management Council
NAMRIA – National
Mapping and Resource
Information Authority
NOAA – National Oceanicand Atmospheric
Administration
OSM – Open Street Map
SRTM – Shuttle Radar
Topography Mission

Low-lying municipalities:

Multispectral Satellite Image of Flooded Areas in Cagayan and Isabela

Typhoon Vamco

Includes material © ISRO 13 Nov.
2020. All rights reserved.

• This false color composite map shows flooded areas inCagayan and Isabela in blue on Nov. 13, 2020.

Detected Flooded Areas in Cagayan and Isabela

Typhoon Vamco• Highlighted in blue arethe observed flooded
areas in Cagayan andIsabela due toTyphoon Vamco on
Nov. 12, 2020
• Please note that flood
extent could beunderestimated inurban areas due tocomplex
backscattering overbuilt surface.
• This map contains
data from Copernicus
Sentinel 1 taken on
Nov. 13, 2020.
• Note also that noground validation wasdone for this map.

Total detected flooded area over the total area on the map:
1,443 km2
Flooded area in Cagayan: 870 km2
Municipalities with flooded area of more than 10 km2): Amulung,Solana, Aparri, Alcala, Enrile, Tuguegarao, Camalaniugan, Lal-lo,Ballesteros, Lasam, Buguey, Gattaran, Allacapan, Baggao, SantoNino, Iguig, Tuao, Abulug
Flooded area in Isabela: 543 km2
Municipalities with flooded area of more than 10 km2):
Ilagan City, Tumauini, Delfin Albano, Cabagan, Cauayan City, Santo
Tomas, Gamu, Naguilian, Quirino, Santa Maria, Reina Mercedes,Alicia, San Pablo, Angadanan, San Isidro, Burgos
Includes material © Copernicus Sentinel 1, 13 Nov. 2020. All rights reserved.

True-color Composite of Sentinel 2 Image of Gattaran, Cagayan

Typhoon Vamco• This true color composite map shows flooded areas in
Gatarran, Cagayan on Nov. 13, 2020. The light brown areas are
the muddy flood waters.
Includes material © Copernicus Sentinel 2, 13 Nov. 2020. All rights reserved.

True-color Composite of Sentinel 2 Image of Amulung, Cagayan

Typhoon Vamco• This true color composite map shows flooded areas inAmulung, Cagayan on Nov. 13, 2020. The light brown areas are
the muddy flood waters.
Includes material © Copernicus Sentinel 2, 13 Nov. 2020. All rights reserved.

True-color Composite of Sentinel 2 Image of Tuguegarao, Cagayan

Typhoon Vamco• This true color composite map shows flooded areas inTuguegarao, Cagayan on Nov. 13, 2020. The light brown areas
are the muddy flood waters.
Includes material © Copernicus Sentinel 2, 13 Nov. 2020. All rights reserved.

Flooded Population in Cagayan and Isabela

Typhoon Vamco• Flooded populationin Cagayan: 290,633• Municipalities inCagayan with morethan 10,000 flooded
population:
Tuguegarao, Solana,Amulung, Aparri,Alcala, Enrile, Lasam,
Ballesteros,
Camalaniugan, Lallo, Iguig• This estimation is based on thedetected flood area, area perbarangay, and PSA’s barangay
population data of 2015.
• No ground truthing was done on
this map.
•PSA – Philippine Statistics Authority• Flooded populationin Isabela: 228,488• Municipalities inIsabela with morethan 10,000 flooded
population: Ilagan
City, Cabagan,
Tumauini, Cauayan
City, Santo Tomas,Santa Maria, Delfin
Albano, Reina
Mercedes, Gamu,
Naguilian

Includes material © Copernicus Sentinel 1, 13 Nov. 2020. All rights reserved.

Affected Population in Cagayan and Isabela as of Nov. 17, 2020

Typhoon Vamco• NDRRMC
reported thatTyphoon Vamco
affected a totalof 296,039
persons inCagayan.
• Tuguegarao,Enrile, Solana,Aparri, Amulung
have the highest
number ofaffected
population(>20,000persons) inCagayan.
• NDRRMC reported that Typhoon Vamco affected a totalof 277,189 persons in Isabela.
• Cabagan, Ilagan, Tumauini, Cauayan, Santiago havethe highest number of affected population (>20,000persons) in Isabela.
•NDRRMC – National Disaster Risk Reduction and Management Council

Includes material © Copernicus Sentinel 1, 13 Nov. 2020. All rights reserved.

Affected land cover in Cagayan and Isabela

Typhoon Vamco• Based on thismap, flooding
affected 1,224
km2 of annual
cropland, 88
km2 of inland
water, 37 km2of open areas,
28 km2 of builtup, and 19 km2
of perennial
cropland.
• Note that theland cover data
used was 5 years
old and that flood
detection fromradar images overbuilt-up area
tends to beunderestimated.

Includes material © Copernicus Sentinel 1, 13 Nov. 2020. All rights reserved.

Affected agricultural area in Cagayan

Typhoon Vamco•

Multi-temporal RGB composite of Sentinel 1B GRDH
IW images captured on (R) November 13, 2020, (G)November 1, 2020, and (B) September 14, 2020.
• Blue portions show the fields possibly planted withrice in September that was covered with water sinceNov. 1.
• Green/Cyan regions show the fields possibly plantedwith rice in August that was flooded on Nov. 13, 2020
due to Typhoon Vamco.
• This map is not ground validated.
Includes material © Copernicus Sentinel 1, 13 Nov. 2020, 1 Nov. 2020, 14 Sept. 2020. All rights reserved.

Affected agricultural area in Isabela

Typhoon Vamco•

Multi-temporal RGB composite of Sentinel 1B GRDH
IW images captured on (R) November 13, 2020, (G)November 1, 2020, and (B) September 14, 2020.
• Blue portions show the fields possibly planted withrice in September that was covered with water sinceNov. 1.
• Green/Cyan regions show the fields possibly plantedwith rice in August that was flooded on Nov. 13, 2020
due to Typhoon Vamco.
• This map is not ground validated.
Includes material © Copernicus Sentinel 1, 13 Nov. 2020, 1 Nov. 2020, 14 Sept. 2020. All rights reserved.

Flood (as of Nov. 13, 2020) and location of hospitals

Typhoon Vamco

Includes material © Copernicus Sentinel 1, 13 Nov. 2020. All rights reserved.

Flood (as of Nov. 13, 2020) and location of schools

Typhoon Vamco

Includes material © Copernicus Sentinel 1, 13 Nov. 2020. All rights reserved.

Flooded Roads (as of Nov. 13, 2020)

Typhoon Vamco

Includes material © Copernicus Sentinel 1, 13 Nov. 2020. All rights reserved.

Buildings and Flood in Cagayan and Isabela

Typhoon Vamco

Typhoon Koppu vs. Typhoon Vamco Flooding in Cagayan and Isabela•Typhoon Vamco

In 2015, flooding was also detected on October 20,
2020 after Typhoon Koppu. Flooded areas arehighlighted in light blue. Compared with this previous
flooding, Typhoon Vamco inundated a greater area
(shown in dark blue).

Includes material © Copernicus Sentinel 1, 13 Nov. 2020. All rights reserved.
Includes material © JAXA ALOS PALSAR, 20 Oct. 2015. All rights reserved.

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