Conventional thinking treats ice primarily as a consequence of climate change: when the planet cools, ice grows; when the planet warms, ice melts. Alex Pope has convinced me that this view is mostly wrong. Furthermore, Alex’s somewhat radical hypothesis fits neatly into my New Theory of Climate Resilience, including through our shared focus on the Earth’s oceans.
Join Alex and me on 24th May to discuss all of this and more. You will need to register for this Zoom webinar. There are three sessions across three time zones:
The first session will be at 12noon Brisbane time, CLICK HERE
The second session will be at 1pm London time, CLICK HERE
The third session will be at 4pm Houston time, CLICK HERE
After you click to register for one or all of the sessions, you will receive an email with a link that you will need to keep to be able to join that session on Saturday 24th May.
While Milankovitch cycles set the stage for glacial-interglacial transitions, they don’t fully account for the speed, magnitude, or mechanisms of events like the 120 metres of sea level rise beginning some 16,000 years ago.
Milankovitch-driven insolation changes are relatively small (~10–20 W/m² at high latitudes). While sufficient to perhaps initiate ice sheet retreat, they struggle to explain the massive ice volume loss required for a 120-meter sea level rise.
The more usual claim is that ice sheet melting was likely amplified by feedback mechanisms. There are appeals to albedo feedback, the idea being that melting ice exposes darker land/ocean, absorbing more heat even CO₂ feedback that rising temperatures released CO₂ from oceans and permafrost, enhancing greenhouse warming.
The hypothesis that I will be discussing with Alex is quite different, and more complex and a better fit with the measurements.
Meanwhile, I received an email just yesterday, further lamenting my recent focus on C02 and more generally my latest obsession that is developing a new theory of climate change. A learned scholar, an expert in metrology (the study of measurement), wrote from Germany:
Why let yourself be dragged into unimportant questions? CO2 has negligible influence on the climate. Climate is controlled by solar activity (and finally probably by the planets). Period!
So sure of what he knows, but unable to articulate a coherent theory of climate change that fits with the measurements. Because there is so little we truly understand about the weather and climate change, even over the millennia including about glaciation.
There is no unifying theory and too often an appeal to just one variable, for example, gravity (orbits of the planets) even as an external driver affecting solar variability, or carbon dioxide as an internal driver because that suits the current consensus IPCC politics.
What we can surmise as likely to be correct is that around 16,000 years ago, Earth was emerging from the Last Glacial Maximum (LGM, 26,500–19,000 years ago), when vast ice sheets covered North America, Europe, and Asia.
As the climate warmed, these ice sheets melted rapidly, causing global sea levels to rise by approximately 120 meters between ~18,000 and ~6,000 years ago. This equates to an average rate of ~1 meter per century, with pulses like Meltwater Pulse 1A (14,700–14,300 years ago) contributing 20–25 meters in just a few centuries.
In the first webinar in this series (CLICK HERE FOR A SUMMARY), Bill Kininmonth presented a model of the Earth’s climate system emphasising the role of convection by air rising within hot towers, also known as Anvil clouds. I am of, and from the tropics, and I know that these clouds can thunder. They are a feature of the tropical convergence zone straddling the equator moving energy from the bottom to the top of the troposphere. Bill explained that in the tropics, atmospheric temperatures lag ocean temperatures and that the ocean is regulating the temperature of the atmosphere in the tropics.
Alex will emphases that component of the solar energy absorbed by the oceans in the tropics, which begins to move poleward via ocean currents. He will explain that this thermal inertia delays the full impact of solar variations, by which he means varying solar input because of the Milankovitch cycles.
When warm ocean currents reach the poles, if polar oceans are thawed, evaporation accelerates leading to heavy snowfall on land. And so, land ice builds up, cooling the continents and reflecting more sunlight. Ice sheets advance. Thawing ice, in turn, chills polar ocean currents, sending delayed cooling back toward the tropics. According to Alex’s theory, ice cycles regulate Earth’s heat distribution beyond the tropical convergence zone. Indeed, his theory dovetails neatly with Bill’s model.
The background image within the banner at the top of this post has been extracted from the short video by my sometimes scuba buddy and ace underwater photographer Stuart Ireland. The video was filmed as part of the Ocean Geographic Elysium Visual Expedition in 2010. The chart within the banner is from the late Bob Carter.
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
Keep going. Climate clearly involves multiple inputs. One such is variations in solar output. The sun seems to be a variable star, with cycles of centuries and millenia, and output variations of only a few percent. This could be the missing link.
Jen, I guess you are familiar with the theory proposed by Henrik Svensmark? As I understand it in a nutshell, cosmic rays affect the climate by promoting cloud formation. More cosmic rays, more clouds, lower temps. I think the effect of gamma rays on water vapor has been confirmed by experiments at the Hadron Collider. https://physicsworld.com/a/evidence-that-cosmic-rays-seed-clouds/ The amount of cosmic rays reaching our atmosphere is modulated by
1. position of our solar system in the galaxy- this would correspond to very long cycles 2. solar weather cycles- Increased solar wind protects Earth from cosmic rays. this would correspond to shorter weather cycles. It’s worth reading his book ‘The Chilling Stars- a cosmic view of climate change’
So, if ‘warm’ ocean currents reaching the Poles are a primary evaporation ‘driver’ – how do you account for the fact that the oceans are primarily in the Southern Hemisphere?
Temperature fluctuation and evaporation is Orbital, Longitudinal and works via Solar-induced changes in atmospheric Albedo.