How a seemingly small change in average temperatures could trigger lasting changes for life as we know it.
\nHonestly, it\u2019s a great question.<\/p>\n
\u201cWhy is holding global warming to 1.5 degrees Celsius such a big deal?\u201d<\/p>\n
Many people think of the hottest days of the summer where temperatures already hit 40 degrees (that\u2019s 104 degrees Fahrenheit) where they live \u2013 or hotter. Another degree or two is a little bit more uncomfortable, sure, but hardly feels like the end of the world.<\/p>\n
So how does global warming crossing the 1.5-degree line become \u2013 as one reader put it \u2013 \u201can extinction-level event\u201d?<\/p>\n
Spoiler alert: it\u2019s not. At least not for humans. But it is right about the point that scientists project we\u2019ll see some of the climate impacts we already see today begin to go from bad to outright terrifying. It\u2019s about the point where we\u2019ll likely see many natural systems begin to cross dangerous points of no return, triggering lasting changes and transforming life as we know it.
\nTo put it another way, we want to do everything we can to keep warming below 1.5 degrees.<\/p>\n
To understand why, read on. When we talk about 1.5 degrees of warming, we\u2019re talking about the increase in the Earth\u2019s average temperature. We measure this increase from a baseline average temperature in the mid-to-late nineteenth century \u2013 when the Industrial Revolution swung into high gear and people began burning fossil fuels on an unprecedented level, jumpstarting climate change.<\/p>\n The important thing to understand is that global warming that comes from burning fossil fuels is not a uniform process. Due to a host of natural factors, some areas \u2013 like the poles \u2013 are warming much faster than others. So when we talk about preventing 1.5 degrees of global warming, we\u2019re talking about preventing a 1.5 degree increase in the Earth\u2019s average temperature. Some places have already crossed that line. Global warming reaching 1.5 degrees doesn\u2019t mean that average temperatures in some places won\u2019t rise significantly beyond that number. Again \u2013 it\u2019s just the global average. As the Intergovernmental Panel on Climate Change (IPCC) \u2013 basically the gold standard for climate science \u2013 reported: \u201cSeveral regional changes in climate are assessed to occur with global warming up to 1.5\u00b0C compared to pre- industrial levels, including warming of extreme temperatures in many regions.\u201d Europe also had a taste of the new normal last summer, with temperatures soaring above 115 degrees Fahrenheit (46 degrees Celsius) in Portugal. It wasn\u2019t just Portugal either \u2013 the same heatwave roasted countries across the continent, breaking records and costing yet more lives.<\/p>\n All of which is to say, 1.5 degrees is not the limit of how much hotter things will get at some points throughout the year. Far from it.<\/p>\n THE CLIMATE CRISIS DOESN\u2019T START AT 1.5 DEGREES \u2013 IT\u2019S ALREADY HERE<\/strong><\/p>\n Another critical thing to understand about global warming is that it\u2019s not the case that everything up to 1.49999 degrees is rainbows and unicorns and free ice cream for everyone. (But once we cross the 1.5 degrees-line, the Four Horsemen of the Apocalypse polish off their martinis, look at each other, and say, \u201cIt\u2019s go time.\u201d) All of these impacts (and so many more) involve complex systems. Some overlap. Some don\u2019t. But what they all have in common is heat. Heat is the factor that throws natural systems with their delicate checks and balances out of whack.<\/p>\n The (over)simple version is that the more heat added to the Earth\u2019s climate system, the more out of balance natural systems get. The more out of balance natural systems get the more destruction and suffering we see. And it\u2019s almost always poor families and people of color who suffer the most. Well, at about 1.5 degrees of global warming is right about where there\u2019s enough heat to push many of the natural systems that sustain us past a dangerous turning point. THE BAD NEWS: THINGS GET WORSE ABOVE 1.5 DEGREES<\/strong><\/p>\n So here\u2019s the bad news: Back in the fall, the IPCC (remember, our team of global rock star scientists) released a report comparing best projections for what global warming looks like at 1.5 degrees versus 2 degrees. And at 2 degrees, we start getting into scenarios that make most dystopian horror movies look like children\u2019s coloring books.<\/p>\n The IPCC projects that going from 1.5 degrees of global warming to 2 degrees could mean: Bottom line: Going above 1.5 degrees of warming puts millions more at risk of potentially life-threatening heatwaves and poverty. It all but wipes out coral reefs that entire ecosystems rely on worldwide. Seas swallow even more of our cities. And that\u2019s just for starters.<\/p>\n THE GOOD NEWS: HOW MUCH THE PLANET WARMS IS UP TO US<\/strong><\/p>\n The same IPCC report also noted that human activities (i.e. burning fossil fuels, for the most part) have already caused about 1 degree of global warming and that with all the greenhouse gases we\u2019ve already put in the air, average temperatures will keep rising.<\/p>\n But, as the report goes on, \u201cthese emissions alone are unlikely to cause global warming of 1.5\u00b0C (medium confidence).\u201d Which is to say, we still have a shot at holding the line at 1.5 degrees and keep what is already a climate crisis affecting millions from becoming a climate catastrophe.<\/p>\n But we have to act and \u2013 according to the IPCC \u2013 basically cut fossil fuel emissions in half by 2030 to do it. Which means moving very, very quickly to leave oil, coal, and gas behind and accelerate the just transition to clean energy underway around the world. There is such a thing as moving too slowly. With GoShares, we can all do our part speed thing things up with our searches.<\/p>\n","protected":false},"excerpt":{"rendered":" How a seemingly small change in average temperatures could trigger lasting changes for life as we know it. Honestly, it\u2019s a great question. \u201cWhy is holding global warming to 1.5 degrees Celsius such a big deal?\u201d Many people think of the hottest days of the summer where temperatures already hit 40 degrees (that\u2019s 104 degrees […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[2],"tags":[],"yoast_head":"\n
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\nGLOBAL WARMING IS ABOUT AVERAGE TEMPERATURES<\/strong><\/p>\n
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\nTEMPERATURES WILL GET MUCH HOTTER THAN 1.5 DEGREES<\/strong><\/p>\n
\nThen there\u2019s the fact that as average temperatures rise, spikes and heatwaves will go much, much higher than just 1.5 degrees.<\/p>\n
\nThat\u2019s rock-star-scientist-speak for: \u201cIf global warming reaches up to 1.5 degrees, the hottest of the hot temperatures will increase and many (more) places will get dangerously hot.\u201d
\nWe got a preview of what \u201cextreme temperatures in many regions\u201d looked like in 2018.
\nIn Pakistan, a May heatwave took temperatures above 110 degrees Fahrenheit (43.3 degrees Celsius) and cost 65 lives in one city alone.<\/p>\n
\nThat\u2019s because the climate crisis is already here. Today. Higher temperatures are already dragging out droughts and wiping out crops. Himalayan glaciers that provide water to some 240 million people are already melting. Storms like Hurricanes Harvey, Irma, and Marie are already getting stronger and more devastating thanks to climate change. The list goes on.<\/p>\n
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\nSo where does the 1.5-degree number fit in?<\/strong><\/p>\n
\nThink of 1.5 degrees not as an absolute line in the sand, but as a general indicator of where many climate impacts \u2013 on balance \u2013 go from destructive to catastrophic. It\u2019s the sign on the door that leads to somewhere very dark indeed, somewhere no one wants to go.<\/p>\n
\n1.7 billion more people experience severe heatwaves at least once every five years.
\nSeas rise \u2013 on average \u2013 another 10 centimeters (almost 4 inches),.
\nUp to several hundred million more people become exposed to climate-related risks and poverty.
\nThe coral reefs that support marine environments around the world could decline as much as 99 percent.
\nGlobal fishery catches could decline by another 1.5 million tonnes.<\/p>\n
\nIt\u2019s a big ask and a lot to accomplish in less than 12 years. But nothing less than the future of the Earth is at stake. As teenage activist (and inspiration for the school strikes for climate spreading around the world) Greta Thunberg said, \u201cOur house is on fire.\u201d We know what we have to do to put it out.<\/p>\n