Block 8: Tipping Points + Feedback Loops
Push a coffee cup slowly toward the edge of the table. For a while, nothing happens. Then, all at once, something irreversible does.
Task: Name one Earth system you suspect works the same way: slow push, sudden shift. Keep it; today gives you the vocabulary.
Answer in your Field Notebook, dated.
I can define tipping point, apply sign-and-direction reasoning to a climate feedback loop, and defend a position on whether tipping-point uncertainty should change my Brief's Recommendations.
I can use a model to show how energy in vs. energy out sets Earth's climate.
"Use a model to describe how variations in the flow of energy into and out of Earth's systems result in changes in climate."
Where this runs:
- U4 B1: The Greenhouse Effect: How Earth Keeps Warm Enough
- U4 B2: Earth's Energy Balance: The Math
- U4 B4: Human Acceleration of Carbon + The Warming Signal
- U4 B8: Tipping Points + Feedback Loops ← you are here
Assessed:
Chennai Climate Brief: the science sections (K/U components)
On track looks like:
Your brief's physics section traces an energy flow, not just names 'greenhouse effect.'
What today is about
Climate is mostly gradual, but not always.
Some thresholds, once crossed, can't easily be uncrossed: West Antarctic Ice Sheet collapse, AMOC (Atlantic Meridional Overturning Circulation) slowdown, Amazon dieback, permafrost methane release. These are tipping points. Today: what makes a tipping point "tipping" vs. gradual, and which ones are real risks vs. tail-risk possibilities.
Then we apply Unit 1's feedback-loop muscle to climate-specific feedbacks. Ice-albedo feedback: less ice means darker surface, more absorbed radiation, more warming, less ice: positive (amplifying). Water-vapor feedback: warmer atmosphere holds more water vapor, which is itself a greenhouse gas: positive. Permafrost-methane feedback: warming thaws permafrost, releasing trapped methane, more warming: positive. The Systems Diagrammer from Unit 1 helps with sign-and-direction notation.
The block closes with the debate that feeds your Climate Brief's Recommendations section: do tipping-point uncertainties make YOUR Brief's Recommendations more cautious (don't risk crossing thresholds) or more aggressive (act now while gradual mitigation is still possible)? Either position is defensible; the move is to defend it with evidence.
Before you start the work
Start with the Interact: it runs with the whole class. The Watch is projected first, and the Read is the Unit 1 cross-reference.
Today's work: choose one path
All four paths end with at least one sign-and-direction-labeled climate feedback diagram applied to YOUR Brief's challenge.
Open your Class Notebook and type today's entry header as Heading 2:
A: Feb 9 | U4 B8 | Tipping Points + Feedback LoopsB: Feb 10 | U4 B8 | Tipping Points + Feedback Loops
What you're submitting today
Component 1 (K/U) of the Climate Brief locks today: feedback diagram + Recommendations implication.
One sign-and-direction-labeled feedback diagram applied to your Brief's challenge. Then two sentences: does this feedback make me more cautious (don't risk crossing thresholds) or more aggressive (act now while gradual mitigation works) in my Brief's Recommendations? Defend it. This is a K/U component and it locks today: you get a strand band that becomes part of your overall K/U mark.
Submit via Google Classroom (link posted in August)One question before you leave
Three to five minutes. Your answer is saved to your reflection journal, where you can read back everything you have written this year.
Today's reflection is in Google Classroom, under Reflection Journal.
Link posted in AugustSign in with your school account. Your teacher can see what you write here.