By the next decade, every second summer will likely be record-setting hot -- hotter than any summer before it in the past 40 years. What's more, if today's warming trend continues unabated, by 2050, virtually every subsequent summer will be the 'hottest ever'.
Already, the last couple of years this decade have been unusually hot. It's tiring to report how almost every year is 'the hottest yet' or at least features a 'record-breaking hot summer'. Although it's not even over, 2017 is set to be one of the hottest three years on record, according to the World Meteorological Organization (WMO).
“The past three years have all been in the top three years in terms of temperature records. This is part of a long term warming trend. We have witnessed extraordinary weather, including temperatures topping 50C in Asia, record-breaking hurricanes in rapid succession in the Caribbean and Atlantic reaching as far as Ireland, devastating monsoon flooding affecting many millions of people and a relentless drought in East Africa," Petteri Taalas, secretary general of the WMO, told The Guardian earlier this month.
Now, a new study published in the journal Earth's Future suggests such news will become yearly mundanities. According to Francis Zwiers, director of the Pacific Climate Impacts Consortium at the University of Victoria, Canada, and his colleagues, record hot summers are now 70 times more likely than they were in the past 40 years over the Northern hemisphere. As a result, heat waves will intensity and more people will risk losing their lives. A different study published in 2017 estimates a 50-fold increase in lives lost due to freak weather in the old world, from 3,000 today (mean average between 1981-2010) up to 152,000 by 2100.
Zwiers' team employed a 'fingerprint' analysis that compares climate models and observational records for temperature and humidity over the past 40 years. Their analysis suggests with "95 percent confidence" that man-made CO2 emissions and other greenhouse gases like methane are the primary cause for the huge uptick in hot summers. Today, CO2 levels in the atmosphere are 44 percent higher than they were 150 years ago.
This is just the most recent study from a long list of research that found upcoming years will only get hotter and hotter. Another study published in Nature Climate Change found that about 30 percent of the world's population is already vulnerable to life-threatening heat waves for 20 days a year. By 2010, three in every four people could be exposed deadly heatwaves. This, along with other dire consequences like sea level rise and more frequent extreme weather, unless the world urgently puts the breaks on fossil fuels and greenhouse gas emissions.
