Chapter 26. Chapter 26: Climate Change

What are the projections for future warming and what are the potential effects of future warming?

Why You Should Care

Predictions of future climate change hinge on knowing future levels of the greenhouse gases and computer models that accurately predict climate. Current IPCC scenarios about climate change are broken up by different assumptions about the amount of greenhouse gases the world emits each year and how quickly those levels decrease. Best-case scenarios predict a stable climate and minimal additional environmental impacts if the world quickly returns to emission levels from the year 2000. The worst-case scenario predicts a 3–4 degrees C increase by 2050 if the world continues the recent rate of increasing emissions and a slow transition to renewable energy sources.

Increased temperatures could lead to higher agricultural yields, but only up to a certain temperature because then drought would start decreasing yields. All warming scenarios lead to less ice and thus higher sea levels, which is a serious issue for the nearly 70% of the world’s population that lives on coastal plains.