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next_migrationIndustrial civilization faces multiple levels of problems, from the specific to the general. Our single most urgent specific problem is climate change, which we have caused, and which is already troublesome and getting worse. We’ve been warned for decades that climate change would have harmful effects around the world. While many wallowed in denial, most of the rest of us comforted ourselves that the bad things would happen much later, decades or centuries from now, or somewhere else, in poorer nations. After the last two years, with extreme-weather records being smashed regularly and hundreds of people dying as a result, anyone who is paying attention knows that climate disruption is real, it is happening now, and it’s happening around the world, including right here. Let's explore some of the sober scientific predictions of our future.
The Intergovernmental Panel on Climate Change provides regular reports on the state of scientific understanding of climate change. These reports must be understood to be conservative. They are produced by large groups of experts, who are inclined to be cautious about making predictions that are anything less than bulletproof. Some represent governments that would really rather not admit that climate change exists at all. Wild speculation cannot gain general agreement. The IPCC reports are often criticized for not including discussions of possible mechanisms that could make future weather changes or sea level rise worse than predicted.
It is noteworthy, therefore, that the brand-new Summary for Policymakers of Working Group I of the Sixth Assessment Report (IPCC 2021), which deals with what is understood about the physical science involved, includes the following assessments:
o “It is unequivocal that ... [w]idespread and rapid changes in the atmosphere, ocean, cryosphere [ice] and biosphere have occurred.”
o “Since 1750, increases in CO2 (47%) and [methane] (156%) concentrations far exceed – and increases in [nitrous oxide] (23%) are similar to – the natural multi-millennial changes between glacial and interglacial periods over at least the past 800,000 years (very high confidence).”
o “It is virtually certain [99-100%] that hot extremes (including heatwaves) have become more frequent and more intense across most land regions since the 1950s ... Some recent hot extremes ... would have been extremely unlikely [<5% chance] to occur without human influence....”
o “Global mean sea level has risen faster since 1900 than over any preceding century in at least the last 3000 years (high confidence).”
o “Global warming of 2°C would extremely likely [>95% certainty] be exceeded in the intermediate GHG emissions scenario.”
o “With every additional increment of global warming, changes in extremes continue to become larger.... There will be an increasing occurrence of some extreme events unprecedented in the observational record [emphasis added] with additional global warming, even at 1.5°C of global warming. Projected percentage changes in frequency are higher for rarer events (high confidence).”
o 10-year hot-temperature events now, at 1°C warming, likely [>66% certainty] occur 2.8 times more often than in 1850–1900 (range: 1.8–3.2 times) and are 1.2°C hotter. At 2°C, they would likely occur 5.6 times more often (range: 3.8–6.0); at 4°C they would likely occur 9.4 times more often (range: 8.3–9.6) and be 5.1°C hotter.
o 50-year hot-temperature events now likely occur 4.8 (2.3–6.4) times more often than in 1850–1900; at 2°C they would likely occur 13.9 (6.9–16.6) times more often, and at 4°C, 39.2 (27.0–41.4) times more often.
o “A warmer climate will intensify very wet and very dry weather and climate events and seasons, with implications for flooding and drought (high confidence)....”
o “It is virtually certain that global mean sea level will continue to rise over the 21st century.... In the longer term, sea level is committed to rise for centuries to millennia....”
o “Concurrent extremes [heatwaves coupled with droughts] at multiple locations, including in crop-producing areas, become more frequent at 2°C and above compared to 1.5°C global warming (high confidence).”
o “Achieving global net zero CO2 emissions ... is a requirement for stabilizing CO2-induced global surface temperature increase.”
High-emissions, high-consumption scenarios would see the global climate system blowing far past 2°C or perhaps even 4°C before the end of the century. Fortunately, there is some reason to hope [!] that industrial civilization will decline sharply due to resource depletion before we can actually extract and burn enough fossil fuel for the worst-case scenarios to occur. But what we are certainly not doing is moving the world into a low-consumption scenario, in which we would quickly achieve net-zero carbon, then go below net-zero as carbon sinks uptake the excess. That would require that we enforce drastic, widespread reductions in fossil fuel extraction and burning, fossil-fueled industrial production, and personal consumption, long before depletion forces those reductions. At best, depending upon who is in power, we send people to international meetings to make positive noises, but then we do very little to discourage carbon extraction or consumption.
Other countries producing high total emissions, such as China, are in the same boat. China has a large class of powerful high-consuming or factory-owning rich people who like the status quo, as we do, plus huge numbers of poor urbanites who can’t be made to cut back much without triggering a revolution. Most wealthier European nations that have real social safety nets and public transportation have cut their carbon emissions far below ours—but they’re still above the level that they need to be at to be sustainable.
People in industrial nations like the creature comforts they’ve been raised with, and have come to think of them as just the way life is. Even in places where it’s legal to live a life of bare-minimum consumption (probably not your town, if you’re an American, especially with kids), most people can’t imagine doing it, and simply won’t do it voluntarily in case it might somehow help to save someone’s life in Bangladesh (or Seattle!) twenty years from now. It just isn’t happening.
Therefore we can make a prediction with “very high confidence” based on our experience of human nature: Climate change is going to get worse, probably a lot worse, before it gets better. And the new normal of “better,” when oceanic currents, temperature, and rainfall patterns stabilize and sea level stops rising, is something nobody alive today, nor their children or grandchildren, will live to see.
So what does climate change mean for the United States? The IPCC report does not attempt to make detailed local predictions. However, it notes that hot extremes have increased in western, northwestern, and northeastern North America, and drought in Western North America, and it is likely that both of those will worsen with every half a degree of temperature increase. The U.S. Global Change Research Program’s (2018) Climate Report focused on attempts to model climate change impacts for individual regions of the U.S., also presenting data on changing climate indicators from the early fossil fuel era to recent years. The following are conclusions from that report.
To begin with, over the previous forty years, heat waves in the U.S. increased every decade. Average temperatures rose in most of the U.S., especially the West, although some parts of the Southeast actually cooled slightly. Sea ice declined, while sea level and ocean acidity rose. Snowpack sharply declined in most of the western U.S., and acres burned by wildfires, though highly variable year-on-year, increased. However, as of the early 2010s there had been no strong nationwide trend to increased drought severity. In the past two decades, heavy precipitation had become more common.
The report predicted that temperatures ultimately would increase everywhere, while sea level rose, especially under high-emission scenarios. The number of hot and very hot days per year would increase across the country, perhaps dramatically if the average temperature increases were very high. Compared to the 1976–2005 average, the authors predicted that this might mean an extra 15 or so days over 110°F per year in Phoenix in the 2016–2045 period. In the 2036–2065 period, it might mean an extra 20 or 30 (or 45) very hot days per year, depending upon emissions. By the 2070–2099 period, the difference in emissions scenarios really kicks in. Though there was much uncertainty, there might be an extra 20 to 50 very hot days per year in the low scenario, vs. 45 to 90 days in the high scenario. Similar scenarios were shown for other cities, though the temperature qualifying as “very high” was usually much lower.
Nationally, coastal flooding and sea level rise were noted to be risks. As of 2013, 42% of the population lived in coastal counties, and about $1 trillion worth of real estate was to be found along the coastlines. At least another 2 feet or so of sea level rise was expected in this century, worse along the sinking coasts of Texas and Louisiana, or perhaps up to 6 feet in some places in a high-emissions scenario. Hurricanes are predicted to have stronger winds and heavier rains in future, though they might become less frequent.
According to current trends and predictions, different regions will experience different water regimes. While the Southeast has had more heavy rain in recent years, the Southwest has seen droughts. Importantly, the area burned by wildfires in the western U.S. per year was estimated to be twice what it would have been without climate change. Tree death in mid-elevation coniferous forests doubled since 1955, due to the direct effects of heat and drought as well as attacks by invasive bark beetles, which spread better in a warmer climate.
The Colorado River supplies water to millions of people in the Southwest, as well as to crops. Though there had been no decline in annual precipitation in the upper Colorado River basin, the temperature in that region had increased substantially (thus, the declining snowpack), the flow of the Colorado River showed a declining trend, and the water volume in the essential reservoirs of Lake Powell and Lake Mead had declined to historic lows. As we will soon see, and as you have probably read in the news already, the condition of these reservoirs has gotten even worse since 2018 and is now approaching the critical.
From a broader perspective, climate change is just one of the many ways in which a society built around the delusion of perpetual growth could shoot itself in the foot. Had the potential for climate change not existed, some other limit to growth would have presented itself. And from an even broader perspective, the collapse of civilizations is not novel. Some dozens of civilizations that we know of have built themselves up then fallen spectacularly. Is there something inherently unstable about our way of life? These issues deserve discussion later, so that those who live in places with plenty of water and adequate elevation don’t presume that their lifestyle is safe. However, climate change is the one known chronic problem that could make millions of Americans into refugees within, if we are unlucky, as little as the next two or three years. Therefore it should be the focus of our most urgent attention today.
