This chapter goes beyond the description of individual events by covering extremes caused by a combination of multiple events. Two main types of interactions are covered: domino effects and compound events. Domino effects, which represent one-way chains of events, are quantified using Markov theory and graph theory. Compound events, which include complex feedback loops in the complex Earth system, are modelled with system dynamics (as in Chapter 4). Two such systems are provided, the ESCIMO climate model and the World2 model of world dynamics. The impact of global warming, pollution, and resource depletion on catastrophes is investigated, as far as ecosystem and societal collapse. The types of catastrophes considered in this chapter are as follows: storm clustering, earthquake clustering (with accelerated fatigue of structures), domino effects at refineries (explosions, fires, toxic spills), cascading failures in physical networks (more precisely blackouts in a power grid), rainforest dieback, lake eutrophication, and hypothetical human population collapse.

Civilisational collapse could occur. The cascading risks attached to climate change could happen within decades or half a century, so it is no longer the next generation that will carry the burdens of the climate emergency. Before the dominoes collapse, we must take climate risks seriously and act accordingly. If we act now, climate risks can be minimised, if not avoided.

We assault the living world from every angle, and all at the same time. As we remember this onslaught, we grieve. Reminiscing is a powerful act. In grieving, we consider the state of our natural environment and take the necessary actions to rectify our abuse of the living planet.

Here we focus on climate impacts, noting first the need to distinguish valid dire climate warnings from breathless scaremongering. Seeking to separate wheat from chaff, we work systematically through the myriad ways in which climate change is expected to impact natural systems including: sea level rise; extreme weather; ocean acidification; ecosystem stress/collapse; water scarcity; and altered global circulations. The resulting human impacts would include: food scarcity; climate migration; health burdens; and heat stress. Predictions in respect of all of these are inherently uncertain and it is therefore difficult to discern how much risk should be acceptable, but it is clear that less risk would be the safer choice.