On average, the planet has warmed by around 1.3 degrees Fahrenheit (0.73 degrees Celsius) since the mid-twentieth century. On particularly frigid winter days, though, you might be less convinced. That’s why scientists prefer pointing to 40-year-long trends, i.e. climate trends, when discussing evidence of changing climate. The problem is that weather, which is measured over much shorter time periods, is just so unpredictable. How can you possibly show that our planet’s climate changing from just any random day? Some scientists recently have.
A team of Swiss climate scientists have demonstrated that today’s Earth is warmer than during the 1950s-’80s – and they can tell by looking at global air temperatures of literally any arbitrary day since 2012. The scientists accounted for natural variability in the climate as well and found that doesn’t explain the recent warming. The findings were published this month in the journal Nature Climate Change.
Everyone already knows the planet is warming, but this is the first time that scientists have demonstrated that we can detect that warming on a daily basis. Bear in mind, though, that the researchers here cannot just monitor temperature at a random point on Earth to detect climate change in daily weather. Instead, they looked at the entire planet at once. To appreciate why looking at global weather is necessary, consider this: weather in a single part of the world is unpredictable, making signs of a warming planet very hard to discern. Though you might be enduring an unusually hot or cold day in your city, it’s unlikely the entire planet is suffering the same fate on the very same day. When the scientists look at the Earth as a whole, many of the unpredictable weather patterns in different areas cancel each other out. Because of that, you get a much more predictable trend when you consider all of the weather across the globe. And as the scientists show, a consistent warming trend emerges – daily.
The researchers do not prove, however, how much of climate change’s imprint on everyday weather is caused by greenhouse gas emissions, such as carbon dioxide from burning fossil fuels. The scientific consensus does point to rapidly rising greenhouse gas emissions as the main culprit. But gases are not the only thing that can cause climate impacts. Land-use change alters regional weather patterns, too. So does air pollution. Even so, the fact that climate change can be detected from any single day of global weather leaves many environmental scientists impressed by the innovative science – and concerned by its findings.
Managing Correspondent: Jordan Wilkerson
Image Credit: flickr