This is what your life will be like when the world hits a dangerous climate tipping point
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A new consensus is growing within the scientific community about climate change: The goal of limiting global warming to 1.5 degrees Celsius by 2050, as set out in the Paris Agreement, is probably out of reach. Weve already experienced the first full calendar year beyond this threshold, with last years global average temperature being 1.6 C higher than that of the preindustrial era. And while a single year at this level isnt enough to confirm without a doubt that the Paris goal is a goner, several recent scientific papers have come to the same unsettling conclusion that a new era of warming has already begun.How hot will things get within our lifetimes? The answer will be determined largely by how quickly we can wean ourselves off fossil fuels, and with greenhouse gas emissions still risingand to new highsthis remains uncertain. But researchers can make an educated guess. Right now they say were on track for about 2.7 degrees Celsius of warming by the end of the century. That means that on average, the world will be about 5 degrees Fahrenheit warmer in 2100 than it was at the turn of the 20th century, or about 3 degrees Fahrenheit warmer than it is today.That may not sound like much, but a 5-degree rise will affect almost every aspect of human life, in ways both large and small. What will life be like in this much warmer world? Answering this question with any certainty is difficult, because so much depends on how the earths many complex and interconnected systems respond. But climate scientists agree a warmer future is a more dangerous one. I like to think of good analogies, says Luke Jackson, an assistant professor of physical geography at Durham University in the U.K. So, if you imagine that scoring a goal represents an extreme event, then the larger the goal, the more likely you are to score. Were widening the goal posts.But if we want to try to get more specific, there are projections that are backed by science. These are some of the changes that are most likely, and their potential trickle-down effects.Endless summerIn the Northern Hemisphere, summer will take up a larger chunk of the year by 2100, extending from about 95 days to 140 days. Summer-like temperatures will appear much earlier, cutting springtime short, and linger well into the fall. Winter will become warmer, too, though theres some debate over whether extreme winter storms will actually become more common as the climate changes. In many places, the warmer seasons will be unbearable, with oppressive heat waves that last for weeks on end.Thanks to the urban heat island effect, cities will be especially hot. San Antonio, for example, could see six heat waves per year, with temperatures lingering around 95 degrees, sometimes for up to a month at a time. Farther north, New York City will get eight heat waves per year, some lasting as long as two weeks. For context, in the early 2000s New York averaged less than one heat wave annually. Air-conditioning will be a literal life-saver, and the number of people with air-conditioning will increase dramatically. (Paradoxically, all these new air conditioners are likely to contribute even more greenhouse gas emissions to the atmosphere.) Still, heat-related deaths will continue to rise to 20,000 annually in the U.S., and thats a conservative estimate.At 5 degrees Fahrenheit of warming, the share of the worlds population living in areas outside the human climate niche (the temperature range at which human life can thrive) would grow from 9% to 40%. Low- and middle-income countries would be disproportionately affected. In India, the most populated country in the world, some 600 million people will feel unprecedented heat outside this niche. Other hard-hit countries will include Nigeria, Indonesia, the Philippines, Pakistan, Sudan, and Niger. The Arctic is predicted to be practically ice-free during summertime. This will accelerate warming even more, and also threaten the homes, livelihoods, and cultures of millions of people in Arctic regions, to say nothing of the wildlife and ecosystems.Fires and DiseaseBy 2100, the number of extreme fires could increase 50% globally. The boreal forests of Canada, Alaska, and Russia will be especially vulnerable. Events like the 2023 Canadian wildfires, which burned more than 37 million acres and sent plumes of smoke billowing across the U.S., will become more common. At the same time, well likely get better at forecasting and tracking wildfires, and, out of pure necessity, more cities will have clean air shelters with filtration systems where people can be protected from wildfire smoke.There will likely be a rise in mosquito-borne illnesses like dengue, Zika, West Nile, and yellow fever, as more warmth will mean more days during which viruses can spread. The peak transmission period for West Nile currently lasts about three months per year in Miami, but would likely increase to about five months. Across much of the Global South, temperatures will become too hot for malaria to spread, but conditions for this disease would become more favorable in other parts of the world, including Europe, North America, and Central Asia. According to the World Resources Institute, As occasional reports arise of locally acquired malaria in Europe and the U.S., there is increasing concern that malaria could creep into places that havent seen it in living memory.Sinking citiesIn a scenario of 5 degrees Fahrenheit of warming, the ice sheets and glaciers will continue to melt, and the sea water will warm and expand. According to the Intergovernmental Panel on Climate Change, in this scenario sea levels could rise about 2 feet on average across the globe by 2100. This will put at risk decades of human development progress in densely populated coastal zones which are home to one in seven people in the world, says Pedro Conceio, director of the United Nations Development Programmes Human Development Report Office.The effect will be more extreme in areas that already have higher-than-average sea levels, such as the U.S. East Coast, Japan, and the west coast of South America. New York City, for example, could see water levels rise more than 3 feet by the end of the century. High-tide flooding will become a regular nuisance in many places, with water seeping into city streets and shop fronts every day for a few hours before receding, making it increasingly difficult to live or do business near the waterfront.Flooding from extreme storms like hurricanes will also become more frequent. Roughly speaking, the vast majority of global coastlines are going to experience a present-day 100-year event every year, Jackson says. Todays extreme event becomes tomorrows normal event.For many low-lying island nations, the challenge of higher seas and more intense tropical storms will be existential. The U.N. projects that the Bahamas, British Virgin Islands, Cayman Islands, Guernsey, Maldives, Marshall Islands, Netherlands, Saint Martin, Seychelles, Turks and Caicos, and Tuvalu will see at least 5% of their territories permanently inundated by the end of the century. Most of the populations of these regions live within a few miles of the shoreline, putting them in grave danger.At the same time that sea levels are rising, coastal megacities that sit on river deltaslike New Orleans, Houston, and Shanghaiwill sink as more water is pumped out of the ground for things like drinking and irrigation, causing the sediment to compact. This is a massive concern for our global megacities, Jackson asserts. Theres a real sting in the tail with that one, because these are places which are some of the most densely populated locations on Earth. In many locations, there are inadequate coastal protections to deal with it, and the length of time it would take to build coastal defenses in order to accommodate for this problem is, frankly, not achievable.Indonesia is already experiencing this, and has planned to relocate its capital city of Jakarta entirely rather than try to keep the water at bay. Other populations may eventually follow. After all, retreat is a form of adaptation, Jackson says. Sea levels will continue to rise for centuries, according to the IPCC, and will remain elevated for thousands of years.Food shortagesFlooding, heat stress, and changing weather patterns will make it harder to grow crops and raise livestock. One estimate suggests up to 30% of the worlds food production could be at risk by 2100 if temperatures rise by 6.6 degrees Fahrenheit. At 5 degrees, the percentage may be slightly lower, but still devastating for millions of people. According to the World Bank, about 80% of the global population most at risk from crop failures and hunger from climate change are in sub-Saharan Africa, South Asia, and Southeast Asia. The threat of malnutrition will stalk these populations.In other regions, like the U.S. and Europe, problems with food will be annoying at first and grow over time, says Kai Kornhuber, a research scientist studying future climate risks at the International Institute for Applied Systems Analysis, and an adjunct assistant professor at the Columbia Climate School. It starts with these small nuisances, like your favorite vegetable is not available anymore for a week or so because there was a huge flood or a heat wave or wildfire in Spain, for instance, he says. These things are already happening, right?Gradually, lower yields for staple crops like corn, rice, and wheat could become the norm. One analysis projects that as early as 2030, Iowa could see corn production plummet 25% due to climate change, Minnesotas soybean yield could drop as much as 19%, and wheat production in Kansas could fall 9%. Without adaptation, those numbers will continue to rise through 2100, threatening farmers livelihoods, as well as food supply chains and nutrition in the U.S. Its not only crops and livestock that are affected, says Gerald Nelson, professor emeritus at the University of Illinois Urbana-Champaigns College of Agriculture, Consumer, and Environmental Sciences. The agricultural workers who plant, till, and harvest much of the food we need will also suffer due to heat exposure, reducing their ability to undertake work in the field.Soil degradation, biodiversity loss, and the collapse of ecosystems due to climate change will leave plants more vulnerable to disease and further exacerbate the risk of crop failure. Food prices around the world will rise. In fact, this is already happening: In 2023, extreme weather was the main driver of food price volatility. Researchers say that between now and 2035, global food prices could rise by up to 3% every year because of climate change.Mass migration and increased conflictIts difficult to know what human migration patterns will look like in the years to come, but many people will have little choice but to move out of rural areas or across borders to find work, food, and a viable human habitat. These mass migrations are likely to trigger conflict and confusion. Attempts to enter the U.S. through the southern border will rise as populations in the dry corridor in Central America face food insecurity. Even the idea of where a countrys borders lie could be thrown into question. The borders of your country are defined, at least along their coasts, by the position of high tide, Jackson explains. If your coastline moves inland [due to sea level rise] your economic zone is going to move too.This is all very bleak, I know. And its only scratching the surface. But the enduring good news is that we can still change the future. Indeed, we already have. Just 10 years ago, scientists were forecasting a global temperature rise of 3.6 degrees Celsius by the end of the centuryor 6.5 degrees Fahrenheit. Since then, new government policies, and the meteoric rise of renewable energy, seem to have made a dent. Still, there is much more to be done. The world will not end like a computer game by the end of the century, Kornhuber says. Its going to continue afterwards, and temperatures and extreme weather will continue to get worse until weve managed to phase out fossil fuels.
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