SCI1300 Lecture Notes - Lecture 2: Daisyworld, Mechanical Equilibrium

• School: Monash University
• Department: Science
• Course: SCI1300
• Professor: Christian Jakob

Document Summary

Sci1300 lecture 2 from science to society. d. (cid:1006)(cid:1005)(cid:1009)(cid:1004) (cid:449)e a(cid:396)e se(cid:374)t to e(cid:454)plo(cid:396)e pla(cid:374)ets a(cid:374)d (cid:374)d dais(cid:455)(cid:449)o(cid:396)ld. It is entirely populated by white daisies on grey land. The lu(cid:373)i(cid:374)osit(cid:455) of dais(cid:455)(cid:449)o(cid:396)ld(cid:859)s sun is increasing at an alarming rate. Let(cid:859)s appl(cid:455) (cid:449)hat (cid:449)e k(cid:374)o(cid:449) a(cid:271)out s(cid:455)ste(cid:373)s to (cid:374)d out. Pe(cid:396)(cid:272)e(cid:374)tage of e(cid:374)e(cid:396)g(cid:455) (cid:396)e e(cid:272)ted (cid:894)e. g. (cid:1004). (cid:1010)(cid:1004) (cid:373)ea(cid:374)s (cid:1010)(cid:1004)% is (cid:396)e e(cid:272)ted(cid:895). Mo(cid:396)e daisies (cid:396)esults i(cid:374) (cid:373)o(cid:396)e sola(cid:396) e(cid:374)e(cid:396)g(cid:455) (cid:396)e e(cid:272)ted (cid:271)a(cid:272)k to spa(cid:272)e a(cid:374)d thus less sola(cid:396) e(cid:374)e(cid:396)g(cid:455) Land albedo is low absorbed by the surface. Less energy absorbed by the surface means the surface cools. If we increase the surface temperature we will increase daisy coverage. This in turn will lead to a higher albedo and the system will cool as a result. Likewise, cooling will reduce the daisy number, leading to lower albedo and warming. So a small perturbation from p1 will make the system return to its original state.