To summarize, climate crisis is the defining issue of the century. Buildup of anthropogenic greenhouse gases (GHGs) in Earth’s atmosphere is driving global heating, while a convergence of global crises threatens to rupture key planetary boundaries beyond which organized human life on Earth would be threatened. Although the human activities which drive these converging crises (for simplicity: the climate crisis) are diverse and complex, the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC) breaks down the sources of anthropogenic GHG emissions into five high-level sectors. Similarly, the impacts of climate crisis – in their variety and complexity – are almost impossible for an individual to grasp, but so far, this sub-series has covered: global heating, Arctic amplification, heat waves, and droughts and floods.
Today’s piece centers disruptions of the currents, circulations, oscillations, etc. in the ocean and the atmosphere that underpin the Earth’s climate as we know it. I can’t (so won’t) pretend an in-depth understanding of the Atlantic Meridional Overturning Circulation (AMOC), the Pacific Decadal Oscillation (PDO), or any of the other interrelated climatic mega-phenomena that were foundational to the ~12,000 years of Holocene stability during which human civilization took shape. (In fact, from my reading of the latest journal articles, it seems that even oceanic and atmospheric scientists are still very much in the process of figuring out how the interactions between the Earth’s atmosphere and oceans work.) Sadly, it seems increasingly clear that these mega-phenomenon are now at risk of collapse or serious disruption under climate crisis. Predicting the impacts of such climatic transformations strikes me as next to impossible, but it is to such likely cataclysmic changes in the fundamental organization of Earth’s life-supporting systems that the term climate regime shift refers. The Holocoene has ended; we are now living through a climate regime shift; and a rational goal, in my view, is to strive to stabilize the planet’s climate in a new regime as favorable as possible to the continuation of organized human life on Earth.
One example of AR5’s measured, vaguely optimistic language regarding such matters follows:
I, for one, don’t take much heart from their prediction, as actual events continue to outstrip the worst of scientists’ climate prognostications, and, after all, ideally we would leave a planet that is inhabitable for humans even after this century…
Following on yesterday’s piece (about droughts and floods), Sidewalk Labs (a subsidiary of Alphabet, aka, Google, and an entity the politics of which can, at some level, be summed up by noting that it claims to be “reimagining cities to improve quality of life” and yet chose to site its headquarters in the Hudson Yards development the construction of which its Chairman and CEO, Dan Doctoroff – in his previous role as Michael Bloomberg’s Deputy Mayor for Economic Development – was instrumental in facilitating) has this interesting piece up about Kansas City’s efforts to manage (through green infrastructure and digital sensors) stormwater runoff. I can also happily recommend the new podcast, Kaalavastha – from our friends Radhika and Samyuktha who must be having success as this latest production of theirs is brought to us by the World Bank – which humanely interweaves social, political, scientific, and climatic threads in recounting the impact of and response to catastrophic flooding in recent years in the Indian state of Kerala.