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 I’m at least going to highlight some of the key impacts in posts that will likely run for the next month or so. Yesterday’s post addressed the most obvious impact of climate crisis: global heating.
Today’s post, centers warming of a cold region of the Earth, namely the Arctic. Arctic amplification refers to phenomenon by which radiative forcing (“the difference between insolation (sunlight) absorbed by the Earth and energy radiated back to space”) “tends to produce a larger change in temperature [in the Arctic] than the planetary average.” Here’s what AR5 has to say about it:
And here’s a piece from Yale Environment 360 from this June the title of which captures much the same message in plain speech: “Temperatures Exceed 100 Degrees F[ahrenheit] North of the Arctic Circle.” It takes no great act of imagination to conjure what impact such warming may have on sea ice, ice sheets, permafrost, Arctic ecologies and human settlements, among other consequences (including the opening of year-round trans-Arctic navigation which people like Mike Pompeo celebrate as “a wonderful economic opportunity“), but as future posts will likely explore those and other topics in more detail, suffice it to say for today that the Arctic is getting rapidly warmer, and that that Arctic warming is both part and parcel of the process of global heating, but also threatens rolling knock-on consequences, including some which could prove rather dire.