Record-hot temperatures of 2015 could soon be the new normal
In less than a decade, the record-breaking hot temperatures we’ve seen lately may have become the “new normal” around the world, climate scientists say. New research predicts that the unusually warm temperatures that made 2015 the hottest year on record by a wide margin will be standard by 2025 if carbon emissions continue to increase at their current rate.
The research was published in the Bulletin of American Meteorological Society.
“If we continue with business-as-usual emissions, extreme seasons will inevitably become the norm within decades and Australia will be the canary in the coal mine that will experience this change first,” lead author Dr. Sophie Lewis, from the Australian National University hub of the ARC Centre of Excellence for Climate System Science (ARCCSS), said in a press release.
The climate trends outlined in the report look worrisome. Lewis said that regardless of whatever actions we take to curb emissions today, the planet was already locked into a pattern of rising temperatures. That being said, the researchers believe that if aggressive action was taken now, record-breaking seasons could be stopped from becoming the norm, at least at the regional level.
If not, summers in some areas could become unbearable within decades.
“That means the record hot summer of 2013 in Australia — when we saw temperatures approaching 50°C [122° Fahrenheit] in parts of Australia, bush fires striking the Blue Mountains in October, major impacts to our health and infrastructure and a summer that was so hot it became known as the ‘angry summer’ — could be just another average summer season by 2035,” Lewis said.
However, she added, that fate could still be avoided “if we reduce emissions drastically to the lowest pathway recommended by the Intergovernmental Panel on Climate Change” — a U.N.-sponsored panel of experts which has developed a plan to keep global temperature increases below 2 degrees Celsius (3.6°F) by the end of the century.
What exactly would it mean to establish a “new normal?” Lewis and her team developed a definition which specifies this would occur when “at least half of the years following a record year were cooler and half warmer.”
The researchers then used a supercomputer that ran climate models to project when a “new normal” would occur based on four different scenarios laid out by the U.N. panel, depending on how much carbon emissions were reduced.
Following this, they looked at seasonal temperatures from December to February throughout Europe, Asia, Australia, and North America. Global average temperatures would hit this “new normal” designation when the climate models were put through all four carbon emission scenarios. This was not the case on a smaller scale when it came to seasonal and regional levels.
Lewis said that if we took strong steps to reduce greenhouse gases globally, seasonal extremes “might never enter a new normal state in the 21st century at regional levels for the Southern Hemisphere summer and Northern Hemisphere winter.”
She used Australia’s “angry summer” of 2013 as a cautionary tale.
“If If we don’t act quickly Australia’s ‘angry summer’ of 2013 may soon be regarded as mild,” she added. “Imagine for a moment, if a summer season like 2013 became average. The likely impacts of an extremely hot year in 2035 would beyond anything our society has experienced.”
