Author: C Dunstan
Research: Google Gemini
Date:August 10, 2026
Spokane Shows What the New Era of Wildfires Looks Like
Moving climate regions.
There is an aspect of climate change that it seems is not well-known and rarely if ever mentioned in reports.
I recall in Geography classes in High School that there is a reason that there are bands of deserts around the world at similar latitudes, north and south of the equator.
The reason is connected with the polar movement of warm, moist air from the equatorial region losing water and heat, then descending in a dry belt the rings the north and south sides of the world - creating arid deserts.
With climate change, the warmer, wetter air travels further towards the poles before descending - leading to the movement of arid climates further towards the poles.
The present hot, dry conditions underpinning wildfires across Canada and Europe receive a lot of media coverage. Describing these as being contributed to by climate change is reasonable, but the mechanism I described may make the connection easier to understand.
Gemini said
Your high school geography memory is entirely accurate. What you are describing is known in atmospheric science as Hadley cell expansion (or the poleward widening of the tropical belt), and it is indeed one of the most significant, yet under-discussed, structural shifts driven by climate change.
The mechanism you outlined provides a clear physical bridge between global warming and the severe, prolonged droughts and wildfires we are increasingly seeing in regions like Canada and Europe.
The Mechanism: How the Hadley Cells Work
To recap the geography lesson on a global scale:
The Ascent: Intense solar heating at the equator causes warm, moisture-laden air to rise rapidly, forming the Intertropical Convergence Zone (ITCZ) and producing heavy tropical rainfall.
The Poleward Journey: As this air reaches the upper troposphere, it flows toward the poles, cooling and losing most of its moisture along the way.
The Descent: By the time this air reaches roughly 30 degrees north and south latitude, it has become cool, dense, and exceptionally dry. It descends back toward the surface, creating a belt of high-pressure systems (the subtropical highs) that suppress cloud cover and rain—naturally forming the world's great deserts (like the Sahara, Atacama, and Australian outback).
How Climate Change Shifts the Belt
As greenhouse gases trap more heat in the lower atmosphere, the energy balance of the planet changes.
Widening Tropics: The rising limb of the Hadley circulation becomes more vigorous, and the upper-level air travels further poleward before it cools enough to descend.
Poleward Migration of Deserts: Consequently, the descending, moisture-suppressing dry belts are shifting further north in the Northern Hemisphere and further south in the Southern Hemisphere.
Compressed Mid-Latitudes: This expansion means that climate zones historically accustomed to regular, temperate weather (like parts of southern Europe, the Mediterranean, and parts of North America) are increasingly subjected to semi-arid, subtropical climate regimes.
Connecting to Wildfires in Canada and Europe
While daily news reports on wildfires usually focus on immediate triggers—like lightning strikes, low seasonal snowpack, or a sudden heatwave—the broader atmospheric baseline is heavily influenced by this shifting circulation:
Blocking Highs: The poleward shift of subtropical high-pressure ridges creates persistent, stable "blocking" high-pressure systems over regions like Western Canada or central/southern Europe. These domes of high pressure act like lids, pushing away rain-bearing weather fronts, baking the soil, and turning forests and brush into tinderboxes.
Prolonged Drying: Because the descending air associated with these expanded dry belts suppresses precipitation over a wider geographic footprint, soils dry out much earlier in the spring and stay dry much later into the autumn.
Boreal Vulnerability: In places like Canada, this climate drift pushes drier conditions deeper into the boreal forest zone, which evolved for cooler, moister conditions. When these forests experience extended multi-year drying trends tied to shifting atmospheric bands, they become primed for catastrophic wildfire seasons.
Why Isn't It Mentioned More Often?
Daily weather reports and even standard climate change news tend to focus on acute, visible symptoms—such as a specific heatwave, a record-breaking temperature, or an active fire front. Macro-scale atmospheric dynamics like Hadley cell expansion happen slowly over decades, making them harder to visualize for general audiences, even though they are altering the fundamental geography of our planet.
While I also found the details of the mechanism a little obscure, the aspect I found most interesting was the realisation that deserts lay in a ring at the same latitudes - and I had not thought of the rarely mentioned Atacama Desert in Chile and the Gobi Desert in Mongolia and Southern China. Once I saw the deserts in two rings around the world at the same northern and southern latitudes it was unforgettable. I only recently thought this may be a more direct explanation for the wildfires currently in the news.
Gemini said
That visual realization—seeing the earth mapped not by political borders, but by two unbroken planetary rings of aridity—is striking. Once you map those subtropical bands (roughly 15 to 30 degrees latitude north and south) and notice how the Sahara, the Arabian Desert, the Thar, the Australian outback, the Kalahari, and the Atacama all line up, the planet's atmospheric engine suddenly becomes entirely tangible.
It is a much more intuitive way to understand climate change than looking at abstract temperature anomaly graphs. Instead of just thinking the world is getting "hotter," seeing it as planetary zones physically sliding poleward makes it immediately clear why regions that used to enjoy reliable temperate moisture—like the Mediterranean basin, parts of southern Australia, and the mid-latitudes of North America and Eurasia—are structurally drying out.
And your instinct to connect those shifting rings directly to modern wildfire regimes hits on the exact reason fire seasons have become so relentless. When those descending dry belts expand upward into higher latitudes, they drag long-term drought conditions into ecosystems (like the Canadian boreal forests or Southern European woodlands) that never evolved to handle sustained subtropical aridity. The trees and soils dry out to unprecedented depths, turning seasonal fire risks into year-round vulnerabilities.
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