Is one of Earth’s great dances,
On downswing curb’s the water’s warmth,
On upswing it enhances.
A subtle giant warms or cools
The vast Pacific surface,
Moves ocean fish and salmon runs
With deep water’s reemergence.
It stirs the clouds and shifts the winds
Wide across the globe,
A pattern in the monthly flux that
Centuries of tree rings hold.
There’s something odd a-happening
Off America’s western coast,
Earth’s wobble spanning decades
Has swallowed warming’s dose.
But what goes cool must then reverse,
The escalator rise.
Droughts will damage farmland
And coral reefs will die.
Salt water will flood coastal zones,
Extinction rates will climb.
These are the precious coins with which
We’ve bought our modern lives.
by Kate Rauner
The Pacific Decadal Oscillation is one of many natural cycles on Earth which interplay with climate. It’s a recent discovery made while studying salmon runs in the North American west: “Over the past century, the amplitude of this climate pattern has varied irregularly at interannual-to-interdecadal time scales… This climate pattern also affects coastal sea and continental surface air temperatures.” Surface temperatures often receive the attention in global warming discussions, though the whole-Earth temperature may be more important.
A “warm blob” is forming in the northeast Pacific Ocean that may represent a change in the PDO, “with one NOAA researcher saying, ‘when you see something like this that’s totally new you have opportunities to learn things you were never expecting.’”
There are many sources for information on global warming, the resulting climate change, and the PDO. Here are a few: