Climate-induced tipping points

We are all familiar with tipping points. The phrase describes a process that typically starts slowly, only to suddenly change and become irreversible at a critical moment.

While numerous tipping points occur in nature and human experience, certain events have radically changed the arc of history. The recent pandemic is a case in point, as the spread of the COVID-19 virus breached a threshold and morphed into a global scourge. Humanity may face a cluster of tipping points as the earth careens toward average temperatures exceeding 2 degrees Celsius. Recent research is slowly unraveling how a warmer planet could trigger biophysical processes that could transform our world in ways that threaten the way we live.

In an article in the journal Science, Armstrong and cowriters (2022) state that “climate tipping points occur when change in a part of the climate system becomes self-perpetuating beyond a warming threshold, leading to substantial Earth system impacts.” They then identified global and regional tipping points that could tilt because of a warming planet. The scary thing is that even if the Paris Agreement goal of not more than 2 degrees warming is met (which is quite unlikely), specific tipping points are projected to happen.

What are the most relevant to the Philippines? First is the collapse of the Greenland ice sheet in the north, and the West Antarctic ice sheet in the south. Such rapid melting of these ice masses will lead to an unprecedented rise of several meters in sea level that would submerge low-lying cities and towns. As a country of small islands, we should pay particular attention to and prepare for this. Second, the Science paper projected that coral reefs would die with temperature increasing even at around 1.5 degrees. Our coral reefs are among the most biodiverse ecosystems in the world, offering a habitat to countless marine organisms and providing food and livelihood to millions of Filipinos. Their loss would be an ecological and socioeconomic disaster of unimaginable proportions.

Aside from the above, there are other tipping points with above 2 degrees of warming, such as the dieback of tropical forests. As the Intergovernmental Panel on Climate Change (IPCC) Synthesis Report (2023) warned, the “likelihood of abrupt and/or irreversible changes and [their impacts] increase with higher global warming levels.” It is worth repeating that tipping points are irreversible. Their impacts could be felt for hundreds, even thousands, of years.

Admittedly, the science of climate tipping points is still in its infancy. However, its initial findings are dire. What can we do as a nation? We must push hard for the United Nations Framework Convention on Climate Change parties to aim for net zero greenhouse gas emissions soon. At the same time, we must support scientific investigation on how our people and ecosystems can adapt to an increasingly uncertain climate. Finally, we must implement innovative measures to enhance the resilience of our country to what lies ahead.

Rodel D. Lasco is one of the authors of the IPCC’s sixth assessment report. He is the executive director of The OML Center, a foundation devoted to discovering climate change adaptation solutions (https://www.omlopezcenter.org/).