This model of planetary temperature with ice albedo feedback. Notice that changing Total Solar Irradiance (TSI) from 1254 to 1253 causes the planet to move from a stable interglacial into an ice ball Earth. This is a very small change in TSI - on the order of the solar fluctuations that take place naturally every decade. See below to find out why such a small change could have such a dramatic result! Change Total Solar Irradiance using the slider - this represents the energy coming from the sun. An image of the planet is shown in the center of the screen. A graph of temperature over time is also shown.
Ice reflects sunlight back into space, which has the result of cooling the planet. That cooling of the planet can cause more ice to form, which will cool the planet further and result in even more ice. This feedback loop can cause wild temperature swings between glacial and interglacial periods. (See for example the end of the last glacial period 10,000 years ago: http://www.antarcticglaciers.org/wp-content/uploads/2012/07/shakun_marcott_hadcrut4_a1b_eng-768x609.png) https://www.coursera.org/learn/global-warming
