Doppler radar now operational to monitor lahar flow around Mayon

By Celso Amo LEGAZPI CITY --- The Philippine Atmospheric, Geophysical and Astronomical Administration (Pagasa) disclosed that the Doppler radar in Bato, Catanduanes is now operational after months spent to repair it. “Our Doppler radar located in Bato, Catanduanes is now semi-operational which has a range of 250 kilometers and can provide early warning on rainfall level,,” Jun Dalida, Pagasa assistant director, said. Dalida said that after the building [on which the equipment was housed] was repaired in February, the Doppler radar was also completed in March this year. He said the doors, windows and air-conditioning unit of the building housing the Doppler radar were earlier reported destroyed. “After the building was repaied, a team from JRC Communication installed the parts needed for the Doppler radar.” “We can now see the real-time images in the morning and afternoon provided by the Doppler radar in Catanduanes on the website of the Pagasa Southern Luzon Services Division,” Dalida said. Dalida said he has given instruction to the Pagasa chief officer manning the Doppler radar to provide input every three hours on a 24-7 basis. “If there’s an incoming typhoon, we can provide images on an hourly update in our websites,” Dalida said. Provincial and local disaster risk reduction and management officers in Albay who were asked by Secretary Francis Tolentino, Mayon crisis manager, to come up with a lahar management and evacuation plan said the whole program is dependent on the forecast by the Doppler radar on the amount of rainfall which could trigger lahar flow. The Philippine Institute of Volcanology and Seismology (Phivolcs) placed the volcanic debris spewed by Mayon Volcano’s eruption starting January 13 at 64.2 million cubic meters comprising as rock falls and pyroclastic density currents at the slopes of the volcano facing the towns of Daraga and Camalig in Albay’s second as well as in Guinobatan and Ligao City in the third district. “Our rainfall warning is one of our very important services to the different provincial disaster risk reduction and management councils as well as Phivolcs especially in Albay,” said Dalida. Dalida said that the amount, volume and direction of rainfall can be seen as clear images through the Doppler radar. “You can trust us to provide you every three hours rainfall advisory and forecast on areas near Mayon Volcano as well as incoming weather disturbance through our operational Doppler radar,” Dalida said. Dalida also cautioned PDRRMC officers to use their imagination to interpret the forecast of Pagasa because the amount of rainfall has direction and moving. “For example, we give a 30 millimeter rain forecast in a specific area it’s not really 30 millimeter of rainfall that is expected in the area because while rain fall towards the surface of the earth they are subjected to about ten percent evaporation. So what we give is a near approximation of what is happening outside as tracked by the Doppler radar,” he explained. He recalled that Pagasa just relied on the weather satellite of Japan which is 36,500 kilometers from the Earth for its weather forecasting and monitoring but an operational Doppler radar rightnear the subject area provides more accurate images of the weather status. He also said that another Doppler radar is being constructed in Cataingan, Masbate to fill the gap which the Doppler radar from Catanduanes cannot reach. “Hopefully, this radar will be operational by next year,” Dalida said as he thanked Masbate Governor Antonio Kho for the support. Another Doppler radar is also being constructed in Laoang, Samar, he added. He said that the recent tropical storm Caloy has affected the north-east moonson which is cold air coming from Japan and China, paving the way for the easterlies which is a humid air from the Pacific Ocean is slowly affecting us. “It’s the easterlies which make us start to feel summer,” said Dalida. Actually in Bicol, the easterlies are slowly being felt despite the sudden occurrence of downpour and thunderstorm due to cloudiness, especially in areas around Mayon Volcano. Dalida said that global warming is being felt and observed with the gradual changes in the weather pattern. “This causes more variability in weather forecasting,” Dalida said. He aadded that summer is officially here when the presence of easterlies is already established, as well as the presence of a high pressure area which is characterized by good weather and lack of rainfall while the north-east moonson stops affecting the country’s weather. But Calida cautioned that there is still the possibility of typhoon coming despite the prevailing summer season. “In fact, there was a possibility for a typhoon to occur during April based on our statistics,” he added. He said the agency will issue an advisory next week to declare the official start of the summer in the country as the north-east moonson or cold air from Japan and China is slowly eased out by the coming easterlies or humid air from the Pacific Ocean. The state-of-the art Doppler radar was inaugurated on May 2, 2012 by President Benigno Aquino III in Barangay Buenavista, Bato, Catanduanes although it was actually started during the administration of former President Gloria Macapagal-Arroyo through the initiative of former Albay Governor Joey Salceda who helped put up Pagasa Southern Luzon Bureau in Legazpi City. Located on top of a hill, the Doppler radar was built through a P1.2B grant from Japan International Cooperation Agency (JICA).