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REPORT
Monitoring of active volcanoes in Peru by the Instituto Geofísico
del Perú: Early warning systems, communication, and
information dissemination
Roger Machacca* , José Del Carpio, Marco Rivera, Hernando Tavera, Luisa Macedo,
Jorge Concha, Ivonne Lazarte, Riky Centeno, Nino Puma, José Torres, Katherine Vargas,
John Cruz, Lizbeth Velarde, Javier Vilca, Alan Malpartida
Instituto Geofísico del Perú, Observatorio Vulcanológico del Sur, Arequipa, Perú.
Abstract
Volcano monitoring in Peru is carried out by the Instituto Geofísico del Perú (IGP), through its Centro Vulcanológico
Nacional (CENVUL). CENVUL monitors 12 out of 16 volcanoes considered as historically active and potentially
active in southern Peru and issues periodic bulletins about the volcanic activity and, depending on the alert-level of
each volcano, also issues alerts and warnings of volcanic unrest, ash dispersion, and the occurrence of lahars. The
information generated by CENVUL is disseminated to the civil authorities and the public through different infor-
mation media (newsletters, e-mail, website, social media, mobile app, etc.). The IGP volcanology team was formed
after the eruption of Sabancaya volcano in 1988. Since then, geophysical and geological studies, volcanic hazards
assessments, and multidisciplinary monitoring realized by the IGP, have provided a comprehensive understanding
of volcanic activity in Peru and forecast future eruptive scenarios. Currently, 80 % of the historically active and
potentially active volcanoes in Peru are equipped with networks of multiparameter instruments, with the seismic
monitoring being the most widely implemented. In this report, we present the situation of volcanic monitoring in
Peru, the monitoring networks, the techniques employed, as well as efforts to educate and inform the public and
officials responsible for disaster risk management.
Este artículo está disponible en español: https://doi.org/10.30909/vol.04.S1.4971 [PDF ES].
1 Introduction
The active volcanic arc of southern Peru results from
the subduction of the Nazca plate beneath the conti-
nental South American plate. The subduction is accom-
panied by a high level of seismicity [Kumar et al. 2016]
and volcanism along the active continental margin. The
active volcanoes of southern Peru are part of the An-
dean Central Volcanic Zone (CVZ) [de Silva and Francis
1991], a segment associated with a steeply dipping (25–
30°) slab extending from 16° S (Southern Peru) to 28° S
(Northern Chile). This segment hosts large rhyolitic
calderas and many composite volcanoes of andesitic-to-
dacitic composition, both of Pliocene and Quaternary
ages [de Silva and Francis 1991; Sébrier and Soler 1991;
Mamani et al. 2010; Thouret et al. 2016]. The Quater-
nary volcanic arc is calc-alkaline and is predominantly
andesitic, although high-silica products (dacites and
rhyolites) are present (e.g., Misti and Huaynaputina
volcanoes), indicating high explosive activity in the re-
cent past.
In this part of the Andes, 127 villages and more than
1,400,000 people are exposed to volcanic hazards. For
example, the city of Arequipa (with over 1 million in-
*Corresponding author: roger.machacca@gmail.com
habitants; 2017 INEI census†), one of the main cities of
Peru, is exposed to a high volcanic risk associated with
a potential reactivation of Misti volcano [Thouret et al.
2001]. Considering this scenario, it is essential to have
an early warning system for volcanic activity that en-
sures that all active volcanoes are monitored, in order
to identify any sign of volcanic unrest or reactivation.
1.1 Volcanism in Peru
In southern Peru, as result of an extensive work [e.g., de
Silva and Francis 1991; Fidel Smoll et al. 1997; Thouret
et al. 2001; Mariño Salazar 2002; Thouret et al. 2002;
Mariño Salazar and Thouret 2003; Gerbe and Thouret
2004; Thouret et al. 2005; Rivera et al. 2010; Harpel et
al. 2011; Siebert et al. 2011; Rivera et al. 2014; Aguilar
2015; Samaniego et al. 2015; Macedo Sánchez et al.
2016; Samaniego et al. 2016; Bromley et al. 2019; Man-
rique et al. 2020; Prival et al. 2020; Rivera Porras et
al. 2020; Rivera et al. 2020], 16 volcanic centres have
been listed as active (at least with an eruption in histor-
ical times „550 yr) and potentially active (with activ-
ity in the Holocene), as shown in Figure 1. Significant
explosive eruptions have occurred in this arc segment
†http://censo2017.inei.gob.pe/resultados-definitivos-de-
los-censos-nacionales-2017/
Volcano Observatories in Latin America: IGP, Peru Machacca et al. 2021
during the late Holocene, including the last Plinian
eruptions of Misti volcano (~2030 years BP) [Thouret
et al. 2001; Harpel et al. 2011; Cobeñas et al. 2012],
Ubinas (~1000 years BP) [Thouret et al. 2005], and
Huaynaputina (1600 CE) [Thouret et al. 2002], as well
as the explosive eruption and collapse of the NE flank
of Tutupaca (1787–1802 CE) [Samaniego et al. 2015].
In addition, Ubinas and Sabancaya, which are among
the most active CVZ volcanoes, during the last cen-
turies have presented several periods of eruptive ac-
tivity with Volcanic Explosivity Index (VEI; [Newhall
and Self 1982]) from 1 to 2. In Ubinas, the most re-
cent eruptions occurred during 2006–2009, 2013–2017,
and 2019 CE, and in Sabancaya between 1990–1998
CE. Currently, Sabancaya volcano presents continuous
eruptive activity since November 2016.
During the last 550 years, there have been at least 45
eruptions at Misti, Ubinas, Sabancaya, Huaynaputina,
Ticsani, and Tutupaca volcanoes, in southern Peru [e.g.,
Rivera et al. 1998; Thouret et al. 2001; Mariño Salazar
2002; Thouret et al. 2002; Gerbe and Thouret 2004;
Siebert et al. 2011; Samaniego et al. 2015]. A recent ex-
ample of highly explosive volcanism occurred at Huay-
naputina volcano 421 years ago. Indeed, on February
19, 1600 CE, a VEI 6 Plinian eruption began. During
the next 17 days a succession of explosions and emis-
sions of volcanic products occurred causing total dev-
astation in an area of 5400 km2. The total bulk volume
of the tephra-fall was estimated as 13–14 km3 [Thouret
et al. 1999; Prival et al. 2020]. This eruption resulted
in the deaths of more than 1500 people, the destruction
of more than 16 villages, and had devastating effects
throughout southern Peru [Thouret et al. 1999].
1.2 Brief history of volcano monitoring at IGP
The Sabancaya volcano unrest in 1986 was the main
catalyst for the development of modern volcanology
in Peru. This episode generated the initiative to es-
tablish a research program to monitor and study ac-
tive volcanoes in the country. In 1988, after the onset
of the Sabancaya crisis, the Observatorio Vulcanológico
del Sur (OVS) was created as part of the Instituto Ge-
ofísico del Perú (IGP) in Arequipa. At that time, the IGP
through OVS implemented some monitoring networks
at Sabancaya volcano, which included five seismic sta-
tions. In those early years, and thanks to the support
of institutions such as the Institut de Recherche pour le
Développement (IRD, France), the Universidad Nacional
de San Agustín (UNSA), and the Autonomous Authority
of Majes-Siguas (AUTODEMA), a research team was cre-
ated. Unfortunately, this first seismic network was re-
moved after the eruption.
Years later, in 2005, in a joint effort between IGP and
IRD, a network of five short-period permanent teleme-
tered seismic stations was installed at Misti volcano. A
further two telemetered stations were added in 2014 at
this volcano. In 2006, Ubinas volcano started a new
eruptive process that lasted until 2009. In response
to this crisis, and with the support of the Ubinas vil-
lage, the first permanent telemetered seismic station
was installed at that volcano (station UBI1). In addi-
tion, three new telemetered seismic stations and tilt-
meters were installed in 2007 at this volcano. Later
in 2019, two further telemetered seismic stations were
added. The data collected by this network have allowed
the detailed and accurate documentation of the evolu-
tion of volcanic activity of Ubinas since 2006, including
the 2006–2009, 2013–2017, and 2019 eruptions [e.g.,
Macedo et al. 2009; Inza et al. 2014]. This, in turn, en-
abled the OVS to issue accurate communications about
the status and the probability of occurrence of an erup-
tion of Ubinas to local and national civil authorities,
and the to the population of Ubinas valley. In 2013,
in response to a new reactivation of Sabancaya volcano,
three permanent telemetered broadband seismic sta-
tions were installed at this volcano, and later in 2015,
2016 and 2018 a total of four new stations were added,
allowing to show valuable observations during the un-
rest and eruption phase on this volcano. Later in 2015,
four seismic stations were installed around Ticsani vol-
cano, and one station was added in 2018.
In 2013, the IGP began the formulation of the public
investment project “Improvement and Expansion of the
Volcanic Risk Warning System in Southern Peru”, and
reached feasibility in 2015 with the support of the min-
istries of the Presidencia del Consejo de Ministros (PCM),
the Ministerio de Economía y Finanzas (MEF), and the
Ministerio del Ambiente (MINAM) of Peru. Through this
project, IGP has upgraded and expanded its monitoring
networks with modern geophysical instruments and
digital telemetry in 12 volcanoes with highest risk in
southern Peru (Table 1). The project made it possible to
monitor more volcanoes and implement other monitor-
ing methods. In August 2019, the Centro Vulcanológico
Nacional (CENVUL) was formally created and attached
to OVS, to continue monitoring and hazard-assessment
program of the IGP. CENVUL is the official service of
the Peruvian State responsible for monitoring and pro-
viding early warnings of future volcanic eruptions in
the country to emergency managers, officials, and the
public. This is one of the most ambitious projects de-
veloped by the IGP and the Peruvian government in re-
cent years, and has also included the build of a modern
building (being finalized) in Sachaca village, Arequipa.
2 Monitoring
Monitoring volcanoes involves the integration of a
number of disciplines, to know of volcanic reactiva-
tion or eruption. Thus, CENVUL makes use of seis-
mology, ground deformation, gas geochemistry, video
camera, infrasound, and satellite-based techniques to
detect eruption precursors in order to provide timely
scientific advice and warnings to civilian authorities.
Of the 16 Peruvian volcanoes listed as active or poten-
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Volcanica 4(S1): 49 – 59. doi: 10.30909/vol.04.S1.4971
Figure 1: Map of southern Peru and the active and potentially actives volcanoes. Red triangles show the locationofmonitored volcanoes. Blue triangles show volcanoes that are not currentlymonitored. From 1 to 16 the followingvolcanoes are 1) Quimsachata, 2) Auquihuato, 3) Sara Sara, 4) Coropuna, 5) Andahua, 6) Huambo, 7) Sabancaya,8) Chachani, 9) Misti, 10) Ubinas, 11) Huaynaputina, 12) Ticsani, 13) Tutupaca, 14) Yucamane, 15) Purupuruni, and16) Casiri.
tially active, 12 are currently monitored by CENVUL.
Given the variety of volcano types and volcanic haz-
ards in Peru [Macedo Sánchez et al. 2016], the level of
monitoring differs from volcano to volcano as described
in Table 1. The data are transmitted to CENVUL as 24-
bit digital signals by UHF radio telemetry where it is
acquired by different data acquisition systems. The im-
plementation of monitoring networks continues today,
and it is contemplated to carry out the monitoring of
the 16 volcanoes in the future.
2.1 Monitoring methods used
2.1.1 Seismic network
Seismic monitoring on Peruvian volcanoes goes back to
the 1990s, when the first seismic network became op-
erational on Sabancaya volcano. Today, CENVUL op-
erates 45 seismic stations which are distributed on 12
volcanoes, six of them are short period (Lennartz
3DLite) and 39 are broadband seismometers (3 are Gu-
ralp 40T, 4 are Guralp 3ESP, and 32 are Trillium Com-
pact 120s). All seismic stations are telemetered. The
number of stations at each volcano depends on its lev-
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Table 1: Distribution of permanent monitoring sensors at Peruvian volcanoes owned and operated by the IGP. Withthe exception of DOAS and Infrasound sensors, all of them are telemetered.
Volcano
Instrument
Seismometer Tiltmeter Camera GPS DOAS Infrasound Multi-Gas Total
Sabancaya 7 – 4 2 2 – 1 16
Ubinas 7 3 3 2 2 1 1 19
Ticsani 5 1 1 – – – – 7
Misti 6 – 2 1 – – – 9
Coropuna 5 2 1 – – – – 8
Yucamane 3 2 1 – – – – 6
Sara-Sara 2 1 1 – – – – 4
Tutupaca 3 1 – – – – – 4
Huaynaputina 3 1 – – – – – 4
Casiri 2 1 – – – – – 3
Cerro Auquihuato 1 1 – – – – – 2
Chachani 1 1 – – – – – 2
els of activity. For example, Ubinas and Sabancaya have
both seven seismic stations (Figure 2), whereas Casiri
and Chachani volcanoes have one station each due to
their low-level of activity. Additionally, we use data
from the Red Sísmica Nacional (RSN) of Peru (operated
by IGP) to reinforce the volcano monitoring of all ac-
tive volcanoes in Peru, and vice versa. For their part,
seismometers deployed at volcanoes complement the
national seismic network for the analysis of regional
earthquakes.
2.1.2 Ground deformation
CENVUL uses different methods to detect ground de-
formation of the flanks of the volcanoes. These in-
clude: Global Navigation Satellite System (GNSS), tilt,
Electronic Distance Measurement (EDM), and satellite-
based measurements. Due to the level of volcanic ac-
tivity and risk, five telemetered GNSS units (Trimble
NetR9 receiver and choke ring antenna) are distributed
around Sabancaya, Ubinas and Misti volcanoes, with a
sampling interval of 30 s and 0.2 s for telemetric trans-
mission and onsite storage, respectively. These instru-
ments have been operating since 2018. Two temporary
GNSS units (Trimble R10) are used for periodical mea-
surements during field surveys (at least twice by year)
at 37 campaign sites distributed around 12 volcanoes.
In addition, CENVUL has 14 telemetered analog tilt-
meters (with ±0.46 degrees of dynamic range) are dis-
tributed at 10 volcanoes, and one Leica Total Station is
used to temporarily measure horizontal displacements
at Misti, Ubinas, and Sabancaya volcanoes. Addition-
ally, we use Interferometric Synthetic Aperture Radar
(InSAR) technique, using Sentinel-1 radar images, to
monitor all volcanoes periodically.
2.1.3 Gas geochemistry
CENVUL uses Differential Optical Absorption Spec-
troscopy (mini-DOAS), Ultra Violet (UV) cameras, and
Multi-GAS analyzer for monitoring volcanic gas emis-
sions (SO2, H2S, and CO2). Two telemetered Multi-GAS
stations are installed at Ubinas and Sabancaya volca-
noes to collect data to measure volcanic gas emissions
rates and concentrations over time. Recently, four UV
cameras and six mini-DOAS were purchased. The mini-
DOAS will be installed with telemetry in the near fu-
ture, while the UV cameras are used in punctual field
campaigns (at least twice a year).
2.1.4 Video cameras
CENVUL has 13 cameras distributed on seven volca-
noes, which provide one image every 30 or 60 sec-
onds depending on the level of activity of each vol-
cano. Thanks to these cameras, the plume elevation,
ash dispersion, and characteristics of volcanic products
emitted from the crater are monitored. In Ubinas and
Sabancaya volcanoes, two cameras have been installed
very close to the main ravines to monitor the descent
of lahars. Likewise, we monitor the volcanoes through
portable thermal cameras (FLIR T1020) in campaigns,
that help us observe the dynamics of the explosions,
such as the range of temperatures of ballistic blocks
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Figure 2: Maps of the instrument monitoring network operated by CENVUL at the top four highest-risk volcanoesin Peru: [A] Sabancaya, [B] Ubinas, [C] Misti, and [D] Coropuna. The black line indicates the limit of Sabancayavolcano in [A]. Some cameras are located outside of the map. All sensors with the exception of infrasound sensorin [B], are telemetered to Arequipa.
ejected and morphology changes in the crater, espe-
cially at night.
2.1.5 Infrasound
CENVUL is beginning to monitor volcanoes with in-
frasound sensors. At the moment, only one not-
telemetered infrasound sensor is in operation at Ubi-
nas volcano, due its high eruption rate and explosive
style. However, thanks to the USGS Volcano Disaster
Assistance Program (VDAP) support, a telemetered 5-
element infrasound array will be installed at this vol-
cano soon.
2.1.6 Remote sensing observations
CENVUL uses satellite-based remote-sensing for vol-
cano monitoring on a local and regional scale. Mon-
itored parameters include SO2 flux, detection of hot
spots in the crater, ash dispersion, topographic changes,
and ground deformation. For example, to detect the
topographic changes and the emplacement of the lava
dome in the summit crater of Sabancaya volcano, us-
ing 13-bands Sentinel-2 Playground images, obtained
every five days Planet images that delivers one image
every day. We also use Planet images obtained ev-
ery day, PERUSAT-1 satellite images, and aerial pho-
tographs taken with drones (in campaigns). To track
ash plumes from eruptions, we use meteorological
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Volcano Observatories in Latin America: IGP, Peru Machacca et al. 2021
imagery (e.g., SEVIRI, GOES, and MTSAT). To detect
thermal anomalies, we use the MIROVA system (Mid-
dle InfraRed Observations of Volcanic Activity) of the
University of Turin, which is based on the analysis
of infrared data acquired by the Moderate Resolution
Imaging Spectroradiometer sensor (MODIS), and uses
the Middle InfraRed Radiation (MIR) recorded with 1
km2 resolution in order to detect, locate, and measure
the heat radiated by hot bodies (e.g., lava flow, dome,
etc.) in MW [Coppola et al. 2015]. The SO2 gas fluxes
are obtained through platforms such as the MOUNTS
system and also processing TROPOMI data via Google
Earth Engine. These data are updated daily and corre-
lated with ground-based monitoring methods (see Fig-
ure 3).
2.2 Staff of volcano observatory
The CENVUL staff consists of 24 scientists and techni-
cal specialists in different disciplines such as: geology
and hazard assessment (two geologists), volcano moni-
toring (six seismologists, two geodesists, two specialists
in remote sensing), technical support (three electronics
engineers, two technicians in electronic and computer
sciences), and administrative support (four profession-
als and three drivers). Additionally, we have admin-
istrative, logistic, and technological support from the
staff of IGP in Lima.
2.3 Data storage and access
CENVUL collects data in near real time from its seis-
mic, GPS, tiltmeter, infrasound, video cameras, and
Multi-GAS instruments. All information is stored in-
ternally in a database using MySQL. In the case of seis-
mic data, for example, acquisition and data process-
ing is performed by several modules of the Earthworm
[Friberg et al. 2010] via RTPD (Real Time Protocol Dae-
mon) protocol on a DELL Power Edge R320 server.
Additionally, we also use Winston software to store
long-term data and SEISCOMP3 for pre-processing. The
raw data can be accessed locally and remotely only by
the monitoring staff, however, requests can be made
through the National Geophysical Data Center (Span-
ish acronym: CNDG). In the case of agreements for re-
search, access to information is free for all team mem-
bers.
3 Volcanic risk management
Volcanoes in Peru provide great benefits, but also
threaten the communities settled in surrounding areas.
Today, about 1.4 million people live in zones directly
subject to volcanic risk. Thus, volcanic risk assessment
and management are important scientific, economic,
and political concerns in these regions. Since 2011, dis-
aster risk management in Peru has been governed by
the Sistema Nacional de Gestión del Riesgo de Desastres
(SINAGERD). SINAGERD has as operational members
the Instituto Nacional de Defensa Civil (INDECI) and the
Centro Nacional de Estimación, Prevención y Reducción
del Riesgo de Desastres (CENEPRED). INDECI is respon-
sible for implementing preparedness and response ac-
tions, while CENEPRED is in charge of disaster risk re-
duction. INDECI is responsible for the Red Nacional
de Alerta Temprana (RNAT, i.e., National Early Warn-
ing Systems), including volcanic hazards. The RNAT
has four components: (1) risk knowledge, (2) monitor-
ing and warning, (3) dissemination and communica-
tion, and (4) response capability. CENVUL contributes
to the first two elements of the RNAT.
Hazard maps are a common component of volcanic
warnings. Thus, between 1990–2003, IGP in coop-
eration with the IRD has produced the first volcanic
hazard maps of Misti [Thouret et al. 1995; Suni 1999;
Thouret et al. 2001], Ubinas [Rivera et al. 1998], Saban-
caya [Thouret et al. 1994], and Ticsani [Mariño Salazar
and Thouret 2003] volcanoes, based on geological stud-
ies aiming to reconstruct the eruptive chronology of the
volcanoes and volcanic hazard evaluation. Currently,
hazard maps are mainly being developed by the In-
stituto Geológico, Minero y Metalúrgico (INGEMMET).
These maps (official and the earlier ones) show three
hazard zones represented in colors: the red color cor-
responds to high danger zones, orange color to mod-
erate danger zones, and yellow color to low danger
zones. These maps are used as communication tools for
education and planning, providing information on ar-
eas most likely to be affected, for example, by ash fall,
pyroclastic flows and other hazards.
Monitoring and warning are essential components of
the RNAT. Thus, CENVUL has been expanding and in-
creasing the level of monitoring at highest risk volca-
noes in Peru. Data collected by the CENVUL is in-
valuable for providing timely and accurate information
on volcanic behavior, forecasting imminent eruptions,
and identifying community impacts. CENVUL has the
mandate to provide official information (reports, bul-
letins, and warnings) of volcanic activity to local, re-
gional and national officials and the public. CENVUL
through its Knowledge Management program, assists
authorities in developing mitigation action plans to re-
duce volcanic risk. All these actions contribute to vol-
canic risk management plans in Peru, towards the pro-
tection of life and property from volcanic events.
4 Information dissemination and out-
reach
CENVUL generates periodic bulletins, alert notifica-
tion, and warnings on the changes in activity of the
12 monitored volcanoes in southern Peru. Once is-
sued, these products are delivered immediately to the
national head of the INDECI, the Centro de Opera-
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Volcanica 4(S1): 49 – 59. doi: 10.30909/vol.04.S1.4971
Figure 3: Example of Dashboard with the main multiparametric data obtained at Sabancaya volcano during 2020:[A] daily seismic energy of explosions; [B] daily count of seismic events; [C] volcano-tectonic seismicity focal depth;[D] uplift of the vertical component of the GPS located at HLCA station (Figure 2A); [E] satellite thermal anomalymeasured by Volcanic Radiative Power (VRP); and [F] plume elevation with respective ash content.
ciones de Emergencia Nacional (COEN), and locally to re-
gional governments and to the decentralized addresses
of INDECI depending on where the volcanoes are lo-
cated. Between 2013 and 2019, the volcanological re-
ports were issued by a joint committee composed of
IGP, INGEMMET, and UNSA. However, since 2019, of-
ficial information has been issued by CENVUL.
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Volcano Observatories in Latin America: IGP, Peru Machacca et al. 2021
4.1 Bulletins and volcanic alerts
4.1.1 Volcanic activity bulletins
Volcanic activity bulletins are technical scientific doc-
uments that contain information based on the anal-
ysis and interpretation of multiparametric data that
describe the activity of a volcano in a given period.
Bulletins are issued regularly for a fixed period (i.e.,
weekly, monthly), depending on the level of volcanic
activity*. These bulletins are short and simple, written
in easy to understand language, addressed to the gen-
eral public, and to the authorities and technical institu-
tions that are part of SINAGERD.
4.1.2 Ash alerts
Ash alerts are communications sent by CENVUL that
describe the occurrence of explosions, in case the ash
columns exceed 2000 m above the crater level. They
indicate the direction of ash dispersion and the possible
urban areas affected. These alerts are available only in
volcanic crises when a volcano is in eruption. They are
also sent to the regional Volcanic Ash Advisory Centre
(VAAC), and local authorities, and those that are part
of the disaster risk management system.
4.1.3 Lahar alerts
Lahars occur frequently during the rainy season at
Misti, Ubinas, Huaynaputina, and Sabancaya volca-
noes, affecting valleys farther downstream. CENVUL
designed a lahar detection and warning system based
on the processing of seismic data and video cameras.
Both seismic stations and video cameras are installed
in the upstream basin areas, where lahars are usually
generated. Once the lahar is detected, an automated
lahar warning message is broadcast to civil defense au-
thorities at local and regional levels. These alerts warn
of the descent of a lahar through the ravines of a vol-
cano, indicating the ravine’s name where the lahar is
descending and the urban areas possibly affected.
4.1.4 Volcano alert levels
The volcano alert levels (VAL) system is an effective
means of communication about the different levels of
activity at a particular volcano and the general preven-
tion measures that the population and its authorities
must adopt to protect its integrity. In Peru, the VAL
system consists of a color ‘traffic light’ scheme, from
green (low level) to red (high level) which corresponds
to a level of activity of a volcano and the measures to
be taken, following the practice of most of other vol-
cano observatories around the world [Gardner and Guf-
fanti 2006]. However, the thresholds for determining
an activity level differ from one volcano to another. The
*https://www.igp.gob.pe/servicios/centro- vulcanologico-
nacional/productos-boletines
green level corresponds to a normal, non-eruptive state,
while the yellow level corresponds to an increase in vol-
canic activity, and the orange level corresponds to a fur-
ther increase in volcanic activity, with recurrent seis-
mic activity, height of eruptive columns greater than
3000 m, constant ash fall, frequent and strong explo-
sions that can eject ballistic blocks. The red level cor-
responds to a critical volcanic activity with imminent
risk of a major eruption, with the occurrence of in-
tense and prolonged earthquakes, constant ejection of
ballistic blocks and ash emissions, formation of erup-
tive columns >4 km in height, and formation of pyro-
clastic density currents (PDCs) that can reach distances
greater than 5 km. IGP periodically communicates to
the civil defense authorities of the regional and local
governments about the state of activity of the volca-
noes, suggesting the level of volcanic alert. In case a
volcano shows signs of reactivation or increased activ-
ity, CENVUL issues a bulletin or report recommending
to the civil defense authorities of the regional govern-
ments the change of alert level, since they are in charge
of assisting the inhabitants of the localities at risk.
4.1.5 Outreach
CENVUL generates diverse educational materials
(brochures, booklets, flyers, etc.) to the officials and
public. These are designed using simple language and
distributed during the visits to the OVS by students,
authorities, and community groups. They are also
distributed at dissemination events organised by the
OVS, such as: in training talks, conferences, evacua-
tion drills, science fairs, etc. Requests must be made
by contacting the official email channels of IGP. Ad-
ditionally, to exchange the knowledge in volcanic risk,
forums, meetings, and workshops are frequently orga-
nized by IGP.
4.2 Communication channels
CENVUL disseminates the bulletins and alerts over dif-
ferent communication channels. (1) Official email ad-
dress*. (2) The VOLCANES PERÚ mobile application
(Android and iOS). Through this application, notifica-
tions are issued notifications every time a new bulletin
is published. (3) The website†, in which the informa-
tion obtained from the different monitoring methods is
published. The website also publishes the latest noti-
fications and bulletins issued on volcanic activity. (4)
The IGP social media: Facebook‡ and Twitter§ and (5)
WhatsApp, through which information about volcanic
activity is sent, mainly to the authorities of several pub-
lic institutions. In addition, this last medium is used
*cenvul@igp.gob.pe
†http://www.igp.gob.pe/servicios/centro- vulcanologico-
nacionaleruptions
‡https://www.facebook.com/igp.peru
§https://twitter.com/igp_peru
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Volcanica 4(S1): 49 – 59. doi: 10.30909/vol.04.S1.4971
for communication with the inhabitants of localities
near volcanoes with eruptive activity, for information
exchange through images, videos and documents.
Information from volcanic monitoring is sent to the
national head of the INDECI and to the directors of the
decentralized addresses of the INDECI of the regions of
Ayacucho, Arequipa, Moquegua, and Tacna, according
to the monitored volcano. The bulletins are also sent
to the regional governors and those responsible for the
Centro de Operaciones de Emergencia Regional (COER) of
each region.
5 Cooperation with public institutions
for disaster risk management
CENVUL cooperates with the national, regional, and
local government agencies to disseminate information
on volcanic hazards and risks. Warnings issued by
CENVUL are sent to the RNAT and its member agen-
cies. INDECI is responsible for emergency manage-
ment in Peru, providing technical advice in the pro-
cesses of prevention, response, and rehabilitation of
natural disasters. It also provides technical assistance
to competent authorities at different levels. Based on
the alert issued, response mechanisms are established
by the agencies in charge of risk management. CEN-
VUL maintains close cooperation with the Local and
Regional Emergency Operations Centers (COEL and
COER, respectively). The decision of these agencies is
made using the technical scientific information issued
by CENVUL for the adoption of measures for the bene-
fit of the population (change of the volcanic alert level,
potential evacuations of people, request for declaration
of state of emergency, preparation of emergency plans,
etc.).
6 Needs, challenges, and future perspec-
tives
CENVUL is a growing IGP service attached to the OVS.
Currently, improvements to the monitoring networks
are being carried out, for which new multi-parametric
monitoring equipment are being installed. However,
one of the major necessities is to acquire more equip-
ment to complete the monitoring of the 16 active or po-
tentially active volcanoes in Southern Peru. The main
challenge in the near future for CENVUL will be the in-
tegration of the different monitoring methods such as
seismic, geodetic, geochemical, visual, tiltmeter, infra-
sound, and remote sensing for better characterization
of volcanic activity and eruption forecasting, as well as
automation in the processing of all signals coming from
volcano monitoring.
Acknowledgements
The authors thank the IGP directors for their valuable
support to the monitoring work. We acknowledge Ing.
H. Palza for his support as former director of the OVS,
the Redes Geofísicas team (D. Portugal, R. Chijcheap-
aza, W. Alvarado, J. Añamuro, M. Ramos, and V. Mon-
tesinos) for their support in data collection and instru-
ment maintenance at the volcanoes, and R. Rivera and
N. Limachi for their administrative support. The Au-
thors gratefully acknowledge the experts who reviewed
the report and provided valuable feedback.
Author contributions
R.M. and M.R. wrote the manuscript. M.R. and L.M.
wrote about volcanic hazard management. J.D.C. and J.
C. wrote about information dissemination. H.T. wrote
the brief history of IGP. R.M., J.D.C., I.L., R.C., N.P.,
J.T., K.V., J.C., and L.V. wrote about the monitoring net-
works and provided information for Table 1, Figure 1,
and Figure 2. A.M. and J.V. wrote the data storage and
access, and provided information for Table 1. All au-
thors reviewed the final manuscript.
Data availability
Data are available through the CENVUL website
(https : / / www . igp . gob . pe / servicios / centro -
vulcanologico- nacional/), and through the corre-
sponding author upon reasonable request.
Copyright notice
© The Author(s) 2021. This article is distributed un-
der the terms of the Creative Commons Attribution 4.0
International License, which permits unrestricted use,
distribution, and reproduction in any medium, pro-
vided you give appropriate credit to the original au-
thor(s) and the source, provide a link to the Creative
Commons license, and indicate if changes were made.
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