Tony Hu, Science Staff Writer
Since the birth of the phenomenon known as climate change, scientists have been trying to understand the changes it brings to Earth and the challenges it poses to humanity. Most agree that climate change is disrupting natural patterns and leading to extreme climate that is both greater in magnitude and more frequent, causing devastating effects to humans and wildlife alike. However, proving that individual events have taken place under the direct influence of climate change is much more difficult. As the negative implications of climate change begin to escalate, an emerging field within climate change science, named Extreme Event Attribution (EEA), promises to shed light on the unsolved question and provide a better model that could more reliably predict and warn of extreme climate events.
Earth’s climate is chaotic—not in the sense that it is totally capricious, dangerous, and wild, but that it is largely unpredictable. Although it is possible to make statistical claims about the most general effects of climate change, like rising temperatures, it is much less feasible to make accurate long-term predictions about local weather. Since extreme climate events usually fall in the latter of the problems, a crude global climate model is not enough to trace their footsteps and identify the ones directly correlated with climate change.
With EEA, however, scientists are taking a different approach. Although the underlying strategies still rely on historical data and computer modelling, EEA uses these tools to create models that are relevant to a much smaller area. These models generally serve two purposes. For one, they process existing data and interpolate to fill the gaps where the data is missing or inadequate. By doing so, they can recreate a more complete extreme event timeline, as well as making predictions on the likelihood of similar events happening in the future. In addition, the models are capable of simulating worlds without anthropogenic alterations to climate. By examining predictions made in those worlds and comparing the course they take with that of the real world, we can directly calculate how much of a role climate change has played in instigating an extreme climate event.
How might knowing such information be useful? Surprisingly, one of the closely related topics is infrastructure. Take the example of a hypothetical coastal city that is regularly impacted by hurricanes and, less often, tsunamis. Being in such a risky position requires the city to develop precautions and plans, such as developing more robust and sturdier building structures, in order to tackle these extreme events if they should happen. However, another crucial variable in this city’s planning is to know the probability of each type of extreme event happening in a given period, such as a year, and their estimated severity. Without these statistics, the city could either be overly prepared and spending a disproportionately high amount of effort against relatively low risk, or have insufficient resources to minimize damage. With its focus in predicting extreme events, EEA is a prospective tool that can provide the city with exactly what it needs. Thanks to its ability to closely track changes in global climate and derive updated predictions, it is also much suited for this task than traditional methods of assessment that may not take into account the ongoing, dynamic change of risks.
Although its future is promising, EEA has several limitations. It cannot predict all extreme events with the same level of confidence. The less prior knowledge available, the less accurate the models will be. Unfortunately, the scarcity of data is still a reality for many kinds of extreme events, since nothing more can be done to acquire the data than to wait for those events to happen. Moreover, just like scientific theories are never truths themselves but are only approaching them, EEA merely provides approximations, and whether the events will happen in reality is only attestable with time.
What is known for sure is that recognizing the risks does not make them any less harmful. Perhaps what humans truly need is not EEA, but a way to prevent these extreme events from becoming more powerful and malicious. The road to achieving that does not require sophisticated research or powerful computer simulation, but simply us being responsible and making the right choice to not let climate change continue its course. When the day arrives that EEA is no longer a necessity, that is its ultimate goal.