By Rodel D. Lasco

The Philippines is projected to be one of the most vulnerable countries to the impacts of future climate change. At the same time, it is one of the most disaster-prone countries in the world, mostly due to climate-related disasters. More alarming still, climate change is expected to exacerbate extreme events such as heavy precipitation and tropical cyclones. The science community must do its share in helping the country prepare for the onslaught of a warming world.

Future changes in extreme events 

• It is very likely that hot temperature and heavy precipitation will continue to become more frequent in the future.
• Number of days with maximum temperature >35°C is expected to increase in all parts of the country in 2020 and 2050.
• Extreme rainfall is projected to increase in Luzon and Visayas in 2020 and 2050.

The temperature differences throughout the years.

Climate change impacts and research priorities 

While there is unanimity that climate change could adversely affect natural and social systems in the country, with the poorest of the poor especially vulnerable, there are very limited evidence-based information. As a result, policy-makers remain largely in the dark on the specifics of how to prepare for climate change. In what follows, we provide a succinct account of how climate change may impact various sectors and what are the key priority research areas.

1. Food security
Climate change threatens food production through a number of ways. First, warming temperature and changing rainfall patterns could affect the physiology of major crops. Preliminary research has shown a potential decline of rice yield and those of other major crops. However, global studies on rice and other crops show that the CO2 gas fertilization could lead to higher yields. Second, sea level rise could inundate crop growing areas, thus, reducing total arable land. Third, extreme events such as tropical cyclones could increase in intensity and frequency leading to greater damage to crops and infrastructure. Fourth, changing rainfall patterns could lead to flooding and droughts which will depress crop yields.

Research priorities:
• Modeling research using downscaled climate scenarios to project yields of crops, livestock, and fisheries in the future
• Socio-economic research on the impacts of climate change to small holder farmers
• Assessment of adaptation strategies for small holder farmers and fisherfolks

2. Water
Climate change could bring higher rainfall during the wet season and drier climate during the dry season. These will modify stream flow, dam operation and water allocation, domestic water supply, irrigation, hydro power generation, depth and recharge of aquifers, water quality, watersheds, and fishery. These, in turn, could adversely affect food and human security and the economy.

Research priorities:
• Modeling climate change impacts on water supply for domestic, power, and irrigation needs
• Identifying most vulnerable river basins
• Assessment of adaptation strategies focusing on water infrastructure, flooding, drought, and increasing water use efficiency

3. Natural ecosystems
Climate change could alter our forest ecosystems and the biodiversity they harbor. Initial research has shown the drier forest types maybe the most vulnerable as overall rainfall increases. Modeling of the potential impacts at the species level of both flora and fauna is still in its infancy. Forest ecosystems are also vital in the mitigation of greenhouse gases in the atmosphere through carbon sequestration. Natural forests in the Philippines store significant amount of carbon while open areas could be reforested to sequester more carbon.

Coastal and marine ecosystems such as mangroves and coral reefs could be affected by sea level rise and warming temperatures. These will lead to loss of mangrove forests, coral bleaching, landward intrusion of seawater in estuaries and aquifers, and submergence and inundation of low-lying areas.

Research priorities:
• Modeling of climate change impacts at the ecosystems and species levels
• Assessment of adaptation strategies for natural ecosystems and local communities living within and around forests
• Measurement of carbon sequestration rates of individual species and at various ecological zones

4. Health
It is expected that the health sector will likewise share the brunt of the impacts of climate change. This could include increases in endemic morbidity and mortality due to diarrheal disease, exacerbation of the abundance and/or toxicity of cholera due to increases in coastal water temperature, and an expansion of the natural habitats of vector-borne and water-borne diseases.

Research Priorities:
• Assessment of the vulnerability of the health sector to climate change
• Improvement of climate-sensitivity and increase in responsiveness of public health systems and service delivery mechanisms to climate change
• Establishment of mechanisms to identify, monitor, and control diseases brought about by climate change

Climate change mitigation

The Philippines’ contribution to the total global greenhouse gas (GHG) emissions is insignificant compared to the rest of the world. In spite of this, the country can help mitigate climate change by cost-effective measures to reduce GHG emissions, including increased energy efficiency and conservation, development and increased utilization of appropriate low carbon and renewable energy technologies, and by reducing emissions from deforestation and forest degradation. To maximize the contribution of forest ecosystems, the Philippines is exploring carbon credits from the so-called REDD+ or reducing emissions from deforestation, forest degradation, and carbon sequestration.

The way forward

As one of the most vulnerable countries in the world to climate change, it is to our best interest to develop evidence-based climate-risk adaptation policies, strategies, and technologies. The science community will continue to play a critical role in defining how we respond to the challenge of climate change. (NAST Bulletin)

This appeared in Agriculture Monthly’s April 2019 issue.