31  motivation

This is a bit grim for motivation, but it is super important.

This is mind-blowingly bad.Most up-to-date study on Atlantic Ocean currents system shows signals of collapse.This could happen in 2025-2095 with 95% probability. Land to grow wheat may drop by half. Winter temperatures in North Europe could drop between 10 and 30 °C. 1/🧵 https://t.co/W1uPEEWus3 pic.twitter.com/yUKoae9b6S

— dr. gianluca grimalda ((GGrimalda?)) February 10, 2024

Let’s discuss what’s going on by looking at these interactive graphs.

Source: Wikimedia

From Westen, Kliphuis, and Dijkstra (2024):

Classical early warning indicators, such as the increase in the variance and/or the (lag-1) autocorrelation, when applied to sea surface temperature-based time series, suggest that the present-day Atlantic meridional overturning circulation approaches a tipping point before the end of this century (11, 12).

31.1 questions

• disconsidering the expected annual cycle, how fast is the ocean warming up?
• what is a typical annual oscillation in temperature?
• how can I model processes such as this, where there are both a clear trend and a seasonal component?

Westen, René M. van, Michael Kliphuis, and Henk A. Dijkstra. 2024. “Physics-Based Early Warning Signal Shows That AMOC Is on Tipping Course.” Science Advances 10 (6): eadk1189. https://doi.org/10.1126/sciadv.adk1189.