Is the Weather Actually Becoming More Extreme?

From 2016 to 2019, the world experienced a series of extreme weather events, including record-breaking heat waves, devastating wildfires, and an unprecedented number of category 5 tropical cyclones. Over the past four decades, the frequency of these extreme events has been on the rise, and projections indicate that this trend is likely to continue. This raises a critical question: Is this increase in extreme weather simply a matter of chance, or is it a consequence of our changing climate?

To understand the answer, it's essential to differentiate between weather and climate, explore how we predict them, and interpret what these predictions reveal.

Weather vs. Climate: Understanding the Difference

Weather refers to the atmospheric conditions at a specific time and place. Meteorologists can currently predict a region's weather for the next week with approximately 80% accuracy. Climate, on the other hand, describes a region's average atmospheric conditions over a longer period, typically a month or more. Climate predictions can forecast average temperatures for decades into the future, but they cannot predict specific weather events.

The Science Behind Weather Forecasting

Weather forecasting relies on measuring the atmosphere's initial conditions, including precipitation levels, air pressure, humidity, wind speed, and wind direction. Twice daily, meteorologists worldwide launch balloons carrying instruments called radiosondes to measure these conditions and transmit the data to international weather centers. This data is then processed through predictive physics models to generate weather forecasts.

However, weather is a fundamentally chaotic system, meaning it is highly sensitive and impossible to forecast perfectly without complete knowledge of all its elements. Even minor disturbances can significantly impact atmospheric conditions within just ten days, limiting the reliable prediction of weather beyond two weeks.

Climate Prediction: A Broader Perspective

Climate prediction is less turbulent because it focuses on the average of all weather data and ignores current atmospheric conditions, instead emphasizing the range of potential outcomes. These parameters, known as boundary conditions, act as constraints on climate and weather.

One crucial boundary condition is solar radiation. By analyzing the distance and angle between a location and the sun, we can determine the amount of heat that area will receive. Since we understand the sun's behavior throughout the year, we can accurately predict its effects on temperature. Averaging this data over years reveals periodic patterns, such as seasons.

Most boundary conditions have well-defined values that change slowly, allowing researchers to reliably predict climate years into the future.

The Impact of Climate Change on Extreme Weather

Even slight changes in boundary conditions can significantly impact the chaotic weather system. For instance, Earth's surface temperature has risen by nearly 1 degree Celsius in the last 150 years. While this may seem minor, it has added the energy equivalent of roughly one million nuclear warheads into the atmosphere.

This massive energy surge has already led to a dramatic increase in heatwaves, droughts, and storm surges.

The Link Between Climate Change and Extreme Weather Events

While weather will always be a chaotic system, shifts in our climate increase the likelihood of extreme weather events. Scientists overwhelmingly agree that our climate is changing and that human activity is accelerating these changes.

By tracking which boundary conditions are shifting, we can identify the human behaviors that most impact the climate. Although predicting next month's weather may remain a challenge, we can work together to protect the climate for centuries to come.

In conclusion, while natural variability plays a role, the increasing frequency and intensity of extreme weather events are undeniably linked to our changing climate. Understanding this connection is crucial for taking meaningful action to mitigate the impacts of climate change and protect our planet.