As we start a new school year, let’s update our understanding of climate change. Here in our idyllic North Fork, we suffer from an ailment that I like to call “back porch, present-day myopia.” We’re seeing reports of intense heat waves, droughts and massive floods setting records around the world, but since we’re not seeing them here it doesn’t seem real. Scientists advise us to worry about 2050 or 2100, but it’s almost impossible to relate to dates that distant. Students, you better start listening.
It is an undeniable, measured fact that the earth has warmed by nearly two degrees Fahrenheit since 1750. It is also unequivocally true that this warming is being caused by human activities, primarily the burning of fossil fuels. No reputable, informed person disputes these facts – and facts are real; they exist whether you believe in them or not.
Scientists around the world have repeatedly warned us that human emissions of greenhouse gases constitute a climate emergency. The physics are simple: emissions of greenhouse gases cause global warming, which causes climate change. The earth will continue to warm up until emissions end. Unfortunately, studies published this summer suggest scientists may have underestimated the danger.
Recently, the American Meteorological Society released its 2021 climate report, and the data is worrying. According to the report, in 2021, atmospheric concentrations of greenhouse gases (carbon dioxide, methane and nitrous oxide) on Earth rose to the highest levels ever recorded. Ocean heat content and global sea level rise were at their highest on record and the Earth’s surface continued to warm, making 2021 one of the six warmest years on record.
Then the National Oceanic and Atmospheric Administration released its 2022 Sea Level Rise technical report. NOAA forecasts that sea levels on the east coast of the United States will rise by 10 to 14 inches over the next 30 years, equivalent to sea level rise in the last 100 years (1920-2020). Perhaps more relevant is this quote: “Current and future emissions matter. Based on past emissions, a sea level rise of about 2 feet along the US coast between 2020 and 2100 is becoming increasingly likely. If future emissions are not curbed, it could add an additional 1.5 to 5 feet to a total of 3.5 to 7 feet by the end of this century.” A potential sea level rise of 3.5 to 7 feet 2100 if emissions continue unabated? Wow!
Then a study reported in Nature Climate Change finds that the Greenland ice sheet, currently one of the main drivers of sea level rise, is in a state of partial collapse that will result in the melting of over 3% of the ice sheet. This massive loss of ice is inevitable—even if we stopped all greenhouse gas emissions today. That much ice melt alone can trigger nearly a foot rise in global sea levels. Although the timeframe of this melt is currently undetermined, the authors suggested that much of it could happen by 2100.
If this news isn’t bad enough, a report in Nature Briefing discusses a phenomenon known as Arctic strengthening. For years, scientists believed the Arctic was warming twice as fast as the rest of the planet. But the new study reports that “the Arctic has warmed nearly four times faster than the rest of the world over the past 43 years. “This is particularly troubling because Arctic warming directly affects our weather, as well as two key amplifying feedback loops that intensify global warming: the ice-albedo feedback and the permafrost-melting feedback. As the Arctic warms, sea ice melts, exposing darker ocean water and reducing Earth’s albedo (reflectance of solar radiation). Sea ice reflects about 90% of the sun’s radiation back into space without warming the earth.
In contrast, the exposed ocean reflects less than 1% of solar radiation. This low albedo means that the oceans absorb about 93% of the incoming heat from the sun, leading to additional global warming. The second feedback loop, melting permafrost (permanently frozen earth), exposes organic matter to bacterial decomposition and releases both carbon dioxide and methane, powerful greenhouse gases that increase global warming.
Fearing apathy, I can’t help but think of the three monkeys sitting in a row, covering their eyes, ears and mouths. For too many Americans, these monkeys represent “not seeing facts; hear no facts; don’t tell facts.” But the facts are real and no blindfold will stop global warming. The bill is due soon and you students will have to pay it.
The good news is that once we reduce greenhouse gas emissions to net zero, global warming will essentially stop. Net-zero emissions means that any new emissions are offset by greenhouse gases removed from the atmosphere. Reaching net-zero emissions in time to avert a lifetime disaster requires the will and commitment to act. Students, the ball is in your hands.
