Global poverty is mostly a rural phenomenon. According to the World Bank, nearly three-quarters of the 650 million people around the world living in extreme poverty are outside towns and cities. The majority are in countries located between the tropics of Cancer and Capricorn, where two-thirds of the population rely on low-productivity small-scale farming.\u00a0<\/p>\n\n\n\n
For these households, weather can have a big impact on production. And abrupt changes in climate make them even more vulnerable.<\/p>\n\n\n\n
Climate change is usually associated with an increase in the incidence and severity of extreme events, such as wildfires, cyclones, droughts and floods. These can ruin agricultural production, directly hurting rural livelihoods (Carleton and Hsiang, 2016<\/a>). Other changes \u2013 such as fluctuations in precipitation or global warming \u2013 are harder to notice but can still have devastating effects on rural incomes.<\/p>\n\n\n\n Global warming refers to a rise in average temperatures. According to the Intergovernmental Panel on Climate Change (IPCC), human activities have already increased average global temperatures by around 1\u00b0C compared with pre-industrial levels (IPCC, 2021<\/a>).<\/p>\n\n\n\n For crop growth in agricultural production, heat can be good, but only up to a point. Plant science shows that exposure to very high temperatures decreases crop productivity. For example, temperatures above around 30\u00b0C are deemed to be harmful to corn (Schlenker and Roberts, 2009<\/a>).<\/p>\n\n\n\n A small increase in temperatures may not sound too bad, but that\u2019s why global warming is like a silent killer: average temperatures rise not because every day is a little hotter, but because the number of extremely hot days increases. More frequent and longer heatwaves mean that crops are exposed to harmful temperatures and, thus, agricultural productivity decreases (see Figures 1 and 2).\u00a0<\/p>\n\n\n\nFigure 1: Change in productivity at different temperatures<\/h4>\n\n\n