Imagine, you are in a space ship. Below is a world with oceans and land, volcanic eruptions, swirling clouds, dust storms, and carpets of green where plants thrive. You prepare to send a shuttle to the surface to explore this new world. What weather will you encounter? What conditions might you have to survive? How will you prepare for the range of conditions you observe from above? How fast might those conditions change? The longer you can observe the surface spectacle from above the better you understand the chaotic conditions you might contend with upon landing.
Humans and all other Earth life have evolved on Earth's surface without this global perspective. Our recent space and satellite technology affords us a view through which we can observe the changing surface conditions, and we have become dependent on it. We forget that our ancestors did not have the benefit of weather predictions and warnings. Instead they became familiar with long term patterns of environmental change, passed down their knowledge from one generation to the next, learned how to interpret changes in the weather, and migrated as needed to ensure their survival.
All Earth life has adapted to Earth's surface environmental conditions, with all the seasonal fluctuations, extreme weather events, and shifting climate patterns. In our modern day technological existence we take for granted that life can & does survive on Earth's surface. We expect the planetary surface to be hospitable, despite the evidence that it often is not. We build cities and assume they will protect us from nature. We assume the patterns of the past will just keep repeating themselves...but Earth is dynamic and the pace of change fluctuates.
Our ancestors most definitely experienced rapid climate change events (RCCEs), times when expected weather patterns changed completely within a few decades. Constant adaptation would have been required to survive these unstable times. When the climate finally reached a new point of stability, new patterns were observed and adapted to. A rapid climate change event (RCCE) is the tumultuous transition from one set of relatively stable climate patterns to a new set of relatively stable climate patterns. During the transition the long term average weather conditions become unpredictable and more extreme. The chaos of the weather reigns. Are Earthlings experiencing a RCCE right now? Has weather become more extreme & less predictable?
Today we rely on weather models to predict rain, snow, storms, and wind. The models have proven themselves, allowing us to plan days in advance. These weather models that we rely on to track hurricanes & winter storms, to predict regions of tornado outbreaks and damaging winds are also used to predict climate trends and how climate will change over the coming decades. Computer climate models predict more extreme weather events, bigger storms, deeper droughts, more flooding, and generally less predictability in our present and future. In recent years, there have been a lot of weather records set around the world. New extremes have been experienced, defying past expectations.
In early 2023 storms brought record rainfall and flooding, unusual cold, and record snowfall to the USA's west coast. In the last few years Texas has experienced multiple arctic blasts with subfreezing temperatures that cause trees to freeze & shatter, pipes to burst, and the electrical grid to fail. How does anthropogenic global warming (=increasing atmospheric temperatures due to increased greenhouse gas levels) cause record cold, winter storms, and arctic blasts? Too many times I've heard people incorrectly assume that global warming could not possibly cause more intense cold and winter storms...when in fact the climate computer models predict that is exactly what will happen, and already is. This is because a significant portion of atmospheric warmth is absorbed into the oceans, and at higher temperatures ocean waters evaporate more quickly, producing more clouds and precipitation. The storms follow the jet stream, which now fluctuates over a larger range of latitudes, bringing cold weather from the north further south, and warm drought weather from the south further north. More atmospheric extremes for everyone, everywhere. In addition, the warmer temperatures cause the glaciers and ice sheets to melt faster, and some of that meltwater won't drain directly into the oceans but will first fill rivers and lakes that overfill and can cause massive flooding. If there are human settlements downstream they are in significant danger, as was witnessed in India in February 2021. When record winter snowfall is followed by a rapid spring thaw, the meltwater flows through the rivers and overflows on to floodplains. Consider that the Central Valley of California was once a series of lakes and marshes formed by Sierra Nevada Range runoff, and this region will flood in the future if there is more melt water and/or rainfall than can be contained by the reservoirs, lakes and rivers. More weather extremes mean more natural disasters.
Think of global warming as adding more fuel to the atmosphere, driving more extreme winter weather patterns - more arctic blasts, more snow in some places, more ice in others...and more fluctuation in all these forms of frozen precipitation. Some years will see a deficit in snow like 2019, and other years will break records like 2020 and 2021 and 2023. We need to prepare for both by looking to the records of the past to form realistic expectations as we prepare for the future. So, in addition to more tropical storms, hurricanes, flooding and fires, anthropogenic global warming will also lead to more winter storms, and more super cold weather. Consider, that ice and snow is falling in unusual abundance in locations that are not glacial (polar), so all that precipitation will melt and flow towards the oceans. It does not stay frozen, instead that water which was evaporated from the ocean returns to the oceans. As the atmosphere and oceans warm, the weather on land will fluctuate more erratically as the weather patterns become more random, and eventually new patterns begin to emerge as a new equilibrium is achieved...but that will take decades.
Global warming doesn't mean warm storms, it means more extreme weather phenomenon, in the same way that a fever doesn't mean you just feel hot, you also get the chills because your internal thermostat is out of equilibrium, so you experience all the extremes. Our ancestors survived rapid climate change events (RCCEs) with no warning at all. Imagine how much more capable we are of adapting and preparing with days to years of warning that extreme weather events are expected. We have satellites, supercomputers, medicine, technology, and engineering that our ancestors never dreamed of. Change is not an enemy, it is a constant life companion, and when we know how things might change we know how to adapt by applying all the tools we have developed.
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