Ocean Warming: the Most Dangerous Challenge
“The scale of ocean warming is truly staggering with the numbers so large that it is difficult for most people to comprehend.”
From the preface to a new IUCN report.
The big thing that most people don’t understand about global warming is that, up to now, most of the heat being generated by our industrial civilization has been being quietly absorbed by the oceans. These oceans cover 75 percent of the planet, and they are now at a tipping point.
That’s the main conclusion of a comprehensive 460-page report, “Explaining Ocean Warming: Causes, scale, effects and consequences”, from the International Union for the Conservation of Nature [IUCN]. “Nature can be vengeful. We should have a great deal of respect for the planet on which we live.”
Warming waters are ready to unlock billions of tons of frozen methane from the seabed, and methane is a far more potent greenhouse gas than CO2. Its effects will literally cook the surface of the planet, even if carbon emissions were to be drastically cut beginning tomorrow, since it’s already too late to turn back the warming of the oceans.
In the preface to the report, we read:
The scale of ocean warming is truly staggering, with the numbers so large that it is difficult for most people to comprehend.
…. If the same amount of heat that has gone into the top 2,000 meters of the ocean between 1955 and 2010 had gone into the lower 10k of the atmosphere, then the Earth would have seen a warming of 36°C [a staggering 64.8°F].
Beyond things like the increasingly severe hurricanes that we’re already experiencing, there are other, more serious effects as the oceans continue to heat up, like the spread of disease, like bacteria that can cause cholera and algal blooms that cause food poisoning.
Fish, seabirds, sea turtles, jellyfish and other animals are migrating to cooler waters five times faster than the shifts seen by land animals. And the effects of ocean warming on phytoplankton, zooplankton and krill are creating problems for ocean animals all the way up the food chain.
More than 550 types of marine fishes and invertebrates are already considered threatened. And as coral reefs bleach and die, they cease to be the birthing places and homes of fully one quarter of all marine species. The coral bleaching, caused directly by warming seas, has increased three-fold over the past 30 years. (The collapse of the Great Barrier Reef is the best-known example.)
Sixty years ago, in Time magazine, meteorologist Carl-Gustav Rossby warned that the oceans were already absorbing heat due to climate change. He speculated that vast amounts of heat might be buried in the oceans and then re-emerge, greatly affecting the planet’s climate. The new report quotes one of his particularly potent and prescient warnings:
“Tampering can be dangerous. Nature can be vengeful. We should have a great deal of respect for the planet on which we live.”
In her introduction to the report, IUCN director general Inger Anderson writes:
“The only way to preserve the rich diversity of marine life, and to safeguard the protection and resources the ocean provides us with, is to cut greenhouse gas emissions rapidly and substantially.”
She doesn’t say how “rapid and substantial” those cuts would need to be. And that’s probably because they would, at very least, have to amount to a complete and immediate shutdown of all industry, the power grids, and anything and everything else that adds more heat to the atmosphere.
But even if that were to happen, the IUCN’s report makes it clear that the die is already cast, and we are now all going to be living with the consequences.