With temperatures in Europe increasing twice as fast as the global average, parts of Spain are turning arid decades earlier than expected. A vast Antarctic glacier may be susceptible to collapse far sooner than anyone realized. The speed of change is head-spinning.
Scientists have spent decades batting away accusations from denialists that they were exaggerating the risks of warming. Now they’re facing the opposite problem. “Some of the impacts of climate change are playing out faster and with a greater magnitude than we predicted,” Michael E. Mann, a climatologist at the University of Pennsylvania, told the U.K.’s Channel 4 News during Europe’s summer heatwave last year.
It’s tempting, in the face of unexpected natural disasters, to ask “why weren’t we warned?” Though the progress of global warming is still closely tracking predictions climate scientists made decades ago, its specific effects can shock even those who’ve dedicated their lives to studying it. Part of the answer lies in the broadness of the techniques used to make verifiable forecasts about an uncertain future. Another part, in the way that our brains, which evolved to help primates make quick judgments, can still misinterpret statistical data.
Our minds latch on to the most easily-available snippets of information, even if we lack the tools to interpret them properly. Global warming of 1.09 C (where we are now), 1.5 C (the level climate diplomats are targeting, likely to soon be out of reach) and 2.8 C to 3.2 C (where we’re currently headed) can’t help but seem mild to people who notch their home thermostats up and down by similar amounts in the course of a day. For experts versed in the science of climate impacts, those numbers conjure up images of mounting, devastating changes to weather, ecosystems and human societies. Lay people, on the other hand, may find it almost beyond comprehension to connect such dry numbers to the real-world disasters they represent.
That disconnect is made worse by the fact that it’s hard to foretell the sorts of short-term disasters that dominate news headlines. You will search scientific literature in vain for predictions of what, for instance, the highest-ever temperature recorded in Delhi will be by the year 2050. Here, instead, is how one 2018 paper on temperature extremes describes its methodology:
The climate of our planet is simply too complex and dynamic to forecast individual events more than a few days in advance. Even moving from global models toward regional ones that give finer-grained detail has been the subject of vast controversy among climatologists, due to disagreements about the usefulness and value of such calculations. Switching from simulations with 100 square-kilometer (39 square-mile) pixels to more granular ones with 1 sq km pixels is the current state of the art, according to Julie Arblaster, a professor at Australia’s Monash University who researches climate extremes. Even that is pushing the limits of our processing power, scientific knowledge and academic labor force.
The emerging science of weather attribution means we are now relatively confident in showing the influence of human-caused climate change on large-scale events like drought, heatwaves and extreme rainfall. Carrying out similar analyses for smaller disasters, such as cyclones, tornadoes and storms, however, remains far more challenging. On top of that, long-range predictions tend to focus more on the increasing frequency of extreme weather, rather than the intensity of record-breaking events. It’s the latter, though, which are more likely to grab the imagination of human brains that have evolved to fear abnormally bad weather as an immediate threat to life and limb.
Science can’t yet provide the high-resolution forecasts that would be needed to make detailed policy for specific areas, says Arblaster. “That local scale of asking what it will be like in Melbourne in 2040 — that’s a difficult question to answer at the moment.”
We’ll have to learn to live with this. The way that climatologists interpret environmental data and the way lay people think about natural disasters are fundamentally different, and often incompatible, systems of information. That lies at the root of the challenges we face in getting the public to comprehend the momentous implications of global warming. In a world where everything seems measurable and quantifiable, scientists can’t provide forecasts with the level of visceral detail that the average person needs to grasp the enormity of the changes unfolding before our eyes.
Rather than dismissing the fears of climate scientists as “alarmism,” we should take their manifest alarm seriously. It may well be our best guide to the damage we are doing to our world.
A Guest Editorial