was initial warming in a Milankovitch cycle small and localised....did co2 make it global
"Note: While Milankovitch cycles triggered past ice ages, the rapid warming over the past 150 years is driven by human-emitted greenhouse gases, not these orbital cycles.:
also
"Antarctic Ice Cores: These records indicate that the Southern Hemisphere (and subsequent CO2 release) often led the global average temperature increase, while the Northern Hemisphere lagged due to the localized cooling effects of melting ice.Amplifier, Not Trigger: CO2 acts as a feedback mechanism that amplifies the initial, small orbital shifts, making them a global, long-term climate shift. "
+11
Yes, the initial warming in a Milankovitch cycle is typically small, localised, and triggers a larger, global response.
Milankovitch cycles (variations in Earth’s orbit, tilt, and wobble) change the amount of sunlight reaching high northern latitudes, not the whole planet equally. This initial, relatively weak, northern-hemisphere-focused warming triggers the release of CO2 from the oceans, which then acts as a major greenhouse gas amplifier that spreads the warming globally.
Skeptical Science
Skeptical Science
+2
How the Process Works
The Trigger: Changes in orbital eccentricity, obliquity (tilt), and precession shift summer sunlight in the Northern Hemisphere, often starting the melting of large ice sheets.
The Small, Localised Start: This initial warming is relatively minor and concentrated at high northern latitudes, rather than a global, uniform warming.
The CO2 Amplification: As the Northern Hemisphere warms, it disrupts ocean currents (like the Atlantic Meridional Overturning Circulation), which in turn warms the Southern Hemisphere.
Making it Global: The warming of the Southern Ocean releases CO2 into the atmosphere. Because CO2 is a well-mixed greenhouse gas, it spreads around the planet, magnifying the weak initial orbital warming into a global, major warming event.
Carbon Brief
Carbon Brief
+4
Evidence for CO2 as the Global Driver
Research, including studies of the last deglaciation, shows that while the orbital changes begin the process, the subsequent CO2 increase is responsible for the vast majority of the warming.
Skeptical Science
Skeptical Science
+1
Roughly 90% of the warming at the end of the last ice age followed the rise in CO2.
Antarctic Ice Cores: These records indicate that the Southern Hemisphere (and subsequent CO2 release) often led the global average temperature increase, while the Northern Hemisphere lagged due to the localized cooling effects of melting ice.
Amplifier, Not Trigger: CO2 acts as a feedback mechanism that amplifies the initial, small orbital shifts, making them a global, long-term climate shift.
Greenly
Greenly
+5
Note: While Milankovitch cycles triggered past ice ages, the rapid warming over the past 150 years is driven by human-emitted greenhouse gases, not these orbital cycles.
Why Milankovitch (Orbital) Cycles Can't Explain Earth's Current Warming - NASA Science https://share.google/W0d66uRh4l1GbwqZn
