Community-based Environmental Observations Catches Quake



Community Monitoring and Preparedness for Natural Disasters


16 June 2005


On 21-22 April 2005, UNDP/COMPREND (see attached background files) partnered with the Lyceum of Batangas to hold a Crustal Stress Consultation 1 in Batangas City, in the southern part of Luzon. The Minutes for this Consultation are also attached with this communication.




About two weeks after the Crustal Stress Consultation 1 in Batangas City, Jean J. Chu, Senior Consultant for UNDP/COMPREND, received the following e-mail from the PPDO[1] Ana Riza Mendoza in Baler, Aurora, a participant in the Consultation 1:


dear jean,


it's been 3 days that the weather here in baler and nearby towns is unusual. i first observed that the environment is somewhat filled with a thin smoke last may 3 around 10PM. i took a look at the window before i went to bed and observed that there was like a smoke that envelopes the environment. i thought that our neighbor burned their dried leaves in the backyard and went to sleep. but the next day, wednesday, may 4, around 5AM, my husband woke me up and told me that it's foggy outside. i went to the rooftop and yes, it was foggy but i would like to describe it as a smoke that is evenly distributed. it was not cold then, which is usually felt when there's a fog. when i went to the office in the morning, i passed through the aguang bridge, it's  the longest bridge in the town of Baler. In aguang bridge, baler bay is usually seen in the east, on the west is the sierra madre mountains and on the north is the mountains where the ASCOT (Aurora State College of Technology) is located. But that particular morning, one cannot see the baler bay and the mountains due to clouds/smoke/fog, i really don't know what that is. Even the ricefields in Brgy. Cabitukulan (road going to Maria Aurora from Baler) are not clearly seen because of the fog/smoke. I had the same observation when i went home in the afternoon. May 5, yesterday, i had the same observation...Then, one of my officemates told us that they had no water yesterday, first time that they experience that the water flowing in their household has no water. But there could be another reason for that such as the pipe is blocked with something. Today, i have the same a student that i asked this morning on my way to work (she happened to ride in the same tricycle where i was boarded) told me that the weather is quite unusual. it's foggy/smokey, but it's hot/humid..she also told me that her uncle who lives in Casiguran sent them a text message last night that they have this fear that the volcano in Casiguran might erupt because there is an area in the said municipality that cannot be seen due to fog/smoke/cloud... and another thing, though this was not validated, in Brgy. Debucao, all water pumps has no water at all, they can only get water from a single pump in the area. This only happened recently, i think this week. i also observed that the water acquifier infront of the Provincial Veterinary Office decreased its water flow.... There are people here that say the weather is really unusual, smokey/foggy but it's hot. it's not actually cloudy because the sun is shining but the sky is not clear. it's difficult to describe actually...i maybe wrong but i may also be right...i sent this to you and you might have an opinion. please do call for anything that needs immediate action. i'll be checking my email next week.


i also informed our PDCC about this (and he has the same observation) but of course, we can't give any warning or whatever because we are not authorized to do so. and besides, WE MAY BE WRONG.... i also called mina buenaflor on my daily observation.


(Above email was sent out and received on May 6, 2005)



Mina Buenaflor, the Community Focal Point for UNDP/COMPREND in the Philippines, sent this email to Jean Chu on May 6, 2005:


Dear Jean,

Please take not(e) of the following unusual observations reported to me via

text by our volunteer in Baler, Riza Mendoza:


1. it has been three days now since she has observed low lying hazy

clouds/fog in their area; her friend reports clouds/fog is darker in

Casiguran area and people are afraid of what they see as this is the first

time they have observed this thing. She explained through a phone call this

is similar to my observations in Baguio before the 91 quake. There is an

active fault line in Casiguran and a volcano(?). Note: There is no reported

typhoon or tropical storm from PAG-ASA but Mt. Kanloan in the Visayas (which

is far from Baler, of course) is active and alert level 1 is up. barangay/community reports that the waterpumps in that area are all

dried up. There is only one source (water pump) where they get water as of

the moment. One of her officemates' waterflowing also dried up yesterday.


She already reported (thru text) these observations to Myllene of PHIVOLCS,[2]

although, there is no response from the latter as of this writing. I am

keeping all her txt messages to me and asked for Mam Laura's number so I cal

call her. Ok, regards. Only FYI. Mina



Upon receipt of these two emails, Jean Chu notified the crustal stress expert team of UNDP/COMPREND in Beijing, sharing with these team scientists the macroprecursors noted by the community volunteers in Baler. The Beijing scientists requested updated crustal stress readings, which they received quickly from the re-energized Luzon crustal stress network, enabling them to study in a timely manner all the information gathered together.


While the Luzon crustal stress network is presently less than 70% operational for forecasting research, with only one of the four eastern Luzon monitoring sites able to regularly record crustal stress readings, the Beijing scientists were able to use the additional macro-precursor information from the Baler community to develop the following community-based research forecast. This research result was faxed to PHIVOLCS on 15 May 2005.


Below, are the actual values of the community-based research forecast, which were received and dated by UNDP/COMPREND on 17 May 2005.


The 3 elements of the Community-Based Research Forecast were:


Forecast Time: 22-29 May 2005 (midpoint is May 26, 2005)

Forecast Magnitude: 5.5-6.0 (midpoint is 5.75)

Forecast Location: 15.9 N, 121.6 E (in the area of Baler, Aurora)

The 3 elements for the Actual Earthquake which occurred were:

(from the USGS NEIC earthquake database):


Earthquake Time: 25 May 2005 (UTC); 26 May 2005 (Manila time)

Earthquake Magnitude:                          5.0

Earthquake Location: 14.68N, 123.90E (east of Baler, Aurora)

A comparison of the Forecast and Actual Earthquake elements show that:


Time is correct

Magnitude is off by 0.75

Location is off by 356 kilometers to the east of Baler.


These results are remarkable, considering that the eastern Luzon crustal stress monitoring sites of Infanta and Aparri are out of operation, and Ilagan's data are greatly delayed and/or incomplete. The Luzon community-based network can strengthen its ability to see ahead if these three north and eastern Luzon sites come into full operation. According to crustal stress expert Professor Huang, the Infanta, Quezon, CSCAN site (destroyed by the landslide and floods last year) was particularly sensitive to identifying the direction of stress/pressure buildup, and would have been very helpful and important in locating the above event accurately.


The above forecasting success comes directly from the keen observations and timely information shared by the Aurora PPDO and her colleague in the PDCC, on macroprecursors noted several weeks prior to the earthquake. The sequence of actions and information flow that occurred between community level observers and national/international scientists in May 2005 illustrate a new way in which local communities can contribute in a major way to seeing ahead for natural disasters.


UNDP/COMPREND seeks to facilitate these kinds of interactions, between community volunteers and professionals interested in community preparedness for natural disasters. When communities are able to see ahead, they can then prepare for any eventuality. Community observations of environmental changes and information sharing are essential for local and global security, as well as for the timely achievement of development goals.





[1] Provincial Planning and Development Officer

[2] Philippine Institute of Volcanology and Seismology (PHIVOLCS)