Olivia Cabrera

Repeat Storm Surge Disasters of Typhoon Haiyan and Its 1897 Predecessor in the Philippines

AbstractOn 8 November 2013, Typhoon Haiyan impacted the Philippines with estimated winds of approximately 314 km h-1 and an associated 5–7-m-high storm surge that struck Tacloban City and the surrounding coast of the shallow, funnel-shaped San Pedro Bay. Typhoon Haiyan killed more than 6,000 people, superseding Tropical Storm Thelma of November 1991 as the deadliest typhoon in the Philippines. Globally, it was the deadliest tropical cyclone since Nargis hit Myanmar in 2008. Here, we use field measurements, eyewitness accounts, and video recordings to corroborate numerical simulations and to characterize the extremely high velocity flooding caused by the Typhoon Haiyan storm surge in both San Pedro Bay and on the more open Pacific Ocean coast. We then compare the surge heights from Typhoon Haiyan with historical records of an unnamed typhoon that took a similar path of destruction in October 1897 (Ty 1897) but which was less intense, smaller, and moved more slowly. The Haiyan surge was about twice the heig...

Multiscale influences on extreme winter rainfall in the Philippines

During 2007–2008, the Philippines experienced the greatest rainfall in 40 winters. We use a combination of observations (including 48 meteorological stations distributed throughout the islands, Tropical Rainfall Measuring Mission satellite-sensed precipitation, and shipboard measurements) along with a high-resolution two-way coupled ocean/atmosphere model (3 km Coupled Ocean-Atmosphere Mesoscale Prediction System (COAMPS)®) to examine this anomalous season. As expected from climatology, rainfall was greatest on the eastern side of the archipelago, with seasonal totals exceeding 4000 mm in some locations. A moderate to strong La Nina increased the rainfall across the region. But discrete precipitation events delivered the bulk of the rain to the area and coincided with intense Madden-Julian oscillation activity over the archipelago and a late February cold surge. General patterns and magnitudes of rainfall produced by the two-way coupled model agreed with observations from land and from space. During the discrete events, the 3 km COAMPS also produced high amounts of precipitation in the mountainous parts of central Philippines. Direct observations were limited in this region. However, the government reported river flooding and evacuations in Mindoro during February 2008 as a result of significant rainfall. In addition, shipboard measurements from late January 2008 (collected by the Philippines Straits Dynamics Experiment) reveal a fresh lens of water to the west of the island of Mindoro, consistent with high freshwater discharge (river runoff) into the coastal area.

Nutrient inputs from submarine groundwater discharge on the Santiago reef flat, Bolinao, Northwestern Philippines.

Submarine groundwater discharge (SGD) on the reef flat of Bolinao, Pangasinan (Philippines) was mapped using electrical resistivity, 222Rn, and nutrient concentration measurements. Nitrate levels as high as 126 μM, or 1-2 orders of magnitude higher than ambient concentrations, were measured in some areas of the reef flat. Nutrient fluxes were higher during the wet season (May-October) than the dry season (November-April). Dissolved inorganic nitrogen (DIN=NO3+NO2+NH4) and soluble reactive phosphorus (SRP) fluxes during the wet season were 4.4 and 0.2 mmoles m(-2) d(-1), respectively. With the increase population size and anthropogenic activities in Bolinao, an enhancement of SGD-derived nitrogen levels is likely. This could lead to eutrophic conditions in the otherwise oligotrophic waters surrounding the Santiago reef flat.

I-C-SEA Change: A participatory tool for rapid assessment of vulnerability of tropical coastal communities to climate change impacts

We present a synoptic, participatory vulnerability assessment tool to help identify the likely impacts of climate change and human activity in coastal areas and begin discussions among stakeholders on the coping and adaptation measures necessary to minimize these impacts. Vulnerability assessment tools are most needed in the tropical Indo-Pacific, where burgeoning populations and inequitable economic growth place even greater burdens on natural resources and support ecosystems. The Integrated Coastal Sensitivity, Exposure, and Adaptive Capacity for Climate Change (I-C-SEA Change) tool is built around a series of scoring rubrics to guide non-specialists in assigning scores to the sensitivity and adaptive capacity components of vulnerability, particularly for coral reef, seagrass, and mangrove habitats, along with fisheries and coastal integrity. These scores are then weighed against threat or exposure to climate-related impacts such as marine flooding and erosion. The tool provides opportunities for learning by engaging more stakeholders in participatory planning and group decision-making. It also allows for information to be collated and processed during a “town-hall” meeting, facilitating further discussion, data validation, and even interactive scenario building.